Resection margin of colorectal cancer surgery / 中华胃肠外科杂志

The judgment of surgical resection margins is an important factor affecting local recurrence and distant metastasis of colorectal cancer, which is crucial to the prognosis of patients. How to select a standard and ideal surgical resection margin is a challenge for colorectal cancer surgeons. Surgical resection margins for colorectal cancer include longitudinal resection margin (LRM) and circumferential resection margin (CRM), and the distance of safe resection margins varies according to different guidelines. Surgical resection margins are mainly evaluated by preoperative imaging, operative experience, operative type, hyperspectral imaging (HPI) and fluorescence angiography (FA), and postoperative pathology. It is the constant pursuit of colorectal cancer surgeons to pay attention to the safe resection margins in colorectal cancer surgery to reduce local recurrence and distant metastasis.

Clinical significance of circumferential margin foresophageal squamous cell carcinoma / 中华胸心血管外科杂志

Objective:To analyze the relationship between the circumferential resection margin status and prognosis and clinicopathological features of esophageal squamous cell carcinoma.Methods:The information of esophageal squamous cell carcinoma patients who underwent radical resection at the Fourth Hospital of Hebei Medical University from October 2017 to March 2019 were collected. All patients were diagnosed with advanced squamous cell carcinoma by postoperative pathology. Demographic data including sex, age, T stage, N stage, tumor location, lesion length, gross pathological type, vascular tumor embolization, nerve invasion and circumferential resection margin were collected and analyzed. The circumferential resection margins were evaluated using the College of American Pathologists(CAP) criteria. A total of 328 cases were included in this study according to the inclusion criteria. Using SPSS 20.0 statistical software, univariate survival analysis was assessed by Kaplan- Meier survival curves, survival curves were compared using Log- rank tests, and multivariate analysis was carried out by Cox regression. The Fisher exact and Chi- square tests were used to compare counting data. Results:As of the follow-up date, the 1-year and 2-year overall survival rates of 328 patients with esophageal squamous cell carcinoma were 91.9% and 84.8%, respectively. The median overall survival was 16 months(range 2-25 months). Univariate analysis showed that T stage, vascular embolism and nerve invasion were the influencing factors of overall survival, multivariate analysis showed that nerve invasion was an independent risk factor for overall survival, stratified analysis showed that the circumferential resection margin was related to overall survival in patients less than 60 years old( P=0.006), patients with ulcerative type of gross pathology( P=0.002) and patients with tumor length ≥4 cm( P=0.046). The 1-year and 2-year disease-free survival rates of the whole group were 89.7% and 67.8%, respectively. The median disease-free survival was 16 months(range 2-25 months). Univariate analysis showed that N stage was the influencing factor of disease-free survival in patients with esophageal squamous cell carcinoma, and stratified analysis showed that the disease-free survival rate of patients with ulcerative type( P=0.002), tumor length ≥4 cm( P=0.015) and circumferential resection margin negative group were better than that of circumferential resection margin positive group. There were 66 patients with positive circumferential resection margin in the whole group, and the positive rate of circumferential resection margin was 20.1%. Univariate analysis showed that T stage, N stage, vascular embolism, nerve invasion and gross pathological type were the influencing factors of circumferential resection margin, while multivariate logistic regression analysis showed that T stage, vascular embolism and gross pathological type were the influencing factors of circumferential resection margin. Conclusion:According to CAP criteria, circumferential resection margin is not related to the prognosis of patients with esophageal squamous cell carcinoma.Positive circumferential resection margins of esophageal squamous cell carcinoma correlate with T stage, vascular embolism, and gross pathologic type, but not with other clinicopathologic features.

Short term efficacy of laparoscopic assisted transanal total mesorectal excision for low rectal cancer: a prospective, multicenter, case registration study / 中华消化外科杂志

Objective:To investigate the short term efficacy of laparoscopic assisted transanal total mesorectal excision (taTME) for low rectal cancer.Methods:The prospective study was conducted. The clinicopathological data of 80 patients who underwent laparoscopic assisted taTME for low rectal cancer in 8 medical centers，including 27 cases in the First Affiliated Hospital of Jilin University，16 cases in the Daping Hospital of Army Medical University，15 cases in the Beijing Friendship Hospital of Capital Medical University，10 cases in the Peking University Cancer Hospital，7 cases in the Peking Union Medical College Hospital of Chinese Academy of Medical Sciences，2 cases in the Peking University People′s Hospital，2 cases in the Liaoning Cancer Hospital Institute，1 case in the Ruijin Hospital of Shanghai Jiaotong University School of Medicine，from August 2017 to September 2018 were collected. Observation indicators：(1) clinical data of enrolled patients；(2) surgical situations；(3) postoperative histopathological examination；(4)postoperative complications and hospitalization. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers and (or) percentages. Results:(1) Clinical data of enrolled patients：a total of 80 patients were selected for eligibility. There were 59 males and 21 females，aged from 53 to 79 years，with a median age of 61 years. (2）Surgical situations：all 80 patients underwent surgery successfully，including 73 cases undergoing low anterior resection，4 cases undergoing Hartmann operation，1 case undergoing intersphincteric and abdominoperineal resection，1 case undergoing other operations and 1 case missing operation information. Nineteen of the 80 patients underwent transabdominal and transanal operations simultaneously. The operation time of 80 patients was 255 minutes (range，211?305 minutes). Of 80 patients，77 cases had the volume of intraoperative blood loss ≤500 mL，3 cases had the volume of intraoperative blood loss >500 mL，44 cases underwent instrumental anastomosis，24 cases underwent manual anastomosis，12 cases were missing anastomosis information，66 cases had specimens been taken out through anus，2 cases had specimens been taken out through Pfannens-tiel incision，10 cases had specimens been taken out through other ways，2 cases were missing the information of specimens removal ways，57 cases underwent preventive stoma，32 cases under-went anal canal indwelling，30 cases underwent free of splenic flexure and 2 cases were converted to open surgery. (3) Postoperative histopathological examination：of 80 patients，68 cases had the integrity of mesorectal specimens with complete，5 cases had the integrity of mesorectal specimens with near complete，1 case had the integrity of mesorectal specimens with not complete，6 cases were missing the information of integrity of mesorectal specimens，1 case had rectal perforation，1 case had positive circumferential margin and 1 case had positive distal margin. The number of lymph node dissected and diameter of tumor were 12(range，9?16) and 3.0 cm(range，1.9?4.0 cm) of 80 patients. Four of 80 patients achieved pathological complete remission. Cases with tumor stage as T0 stage，Tis stage，T1 stage，T2 stage，T3 stage or T4 stage of the pT staging，cases with tumor stage as N0 stage，N1 stage or N2 stage of the pN staging，cases with tumor stage as M0 stage or M1 stage of the pM staging were 4，2，11，24，35，4，55，21，4，75，5 of 80 patients. (4) Postopera-tive complications and hospitalization：8 of 80 patients underwent anastomotic leakage，including 2 cases with grade A anastomotic leakage，4 cases with grade B anastomotic leakage and 2 cases with grade C anastomotic leakage.Seven of 80 patients underwent intestinal obstruction. The 2 cases with grade A anastomotic leakage were improved after symptomatic drug treatment，the 4 cases with grade B anastomotic leakage were improved after treatment with antibiotics or catheter drainage and the 2 cases with grade C anastomotic leakage were improved after operation. The duration of hospital stay of 80 patients was 14 days(range，11?21 days). No patient died during hospitalization.Conclusion:Laparoscopic assisted taTME for low rectal cancer is safe and feasible，which has a good short term efficacy.

What are the most important prognostic factors in patients with residual rectal cancer after preoperative chemoradiotherapy? / 영남의대학술지

BACKGROUND: We aimed to establish robust histoprognostic predictors on residual rectal cancer after preoperative chemoradiotherapy (CRT).METHODS: Analyzing known histoprognostic factors in 146 patients with residual disease allows associations with patient outcome to be evaluated.RESULTS: The median follow-up time was 77.8 months, during which 59 patients (40.4%) experienced recurrence and 41 (28.1%) died of rectal cancer. On univariate analysis, residual tumor size, ypT category, ypN category, ypTNM stage, downstage, tumor regression grade, lymphatic invasion, perineural invasion, venous invasion, and circumferential resection margin (CRM) were significantly associated with recurrence free survival (RFS) or/and cancer-specific survival (CSS) (all p<0.005). On multivariate analysis, higher ypTNM stage and CRM positivity were identified as independent prognostic factors for RFS (ypTNM stage, p=0.024; CRM positivity, p<0.001) and CSS (p=0.022, p=0.017, respectively). Furthermore, CRM positivity was an independent predictor of reduced RFS and CSS, irrespective of subgrouping according to downstage (non-downstage, p<0.001 and p<0.001; downstage, p=0.002 and p=0.002) or lymph node metastasis (non-metastasis, p<0.001 and p=0.001; metastasis, p<0.001 and p<0.001).CONCLUSION: CRM status may be as powerful as ypTNM stage as a prognostic indicator for patient outcome in patients with residual rectal cancer after preoperative CRT.

Current status of prognostic evaluation of esophageal cancer patients by circumferential resection margin / 中华肿瘤杂志

Esophageal cancer is the sixth leading cause of cancer-related death worldwide due to its high malignancy and poor prognosis. In recent decades, the applications of new technologies, devices and neoadjuvant therapy lead to the great progress in the diagnosis and treatment of esophageal cancer. However, the five-year survival rate of esophageal cancer remains unsatisfied. Clinical and pathological factors such as the primary tumor (T), regional lymph nodes (N) and distant metastasis (M) and the longitudinal margins of esophageal lesions, lymphatic invasion, peripheral nerve invasion have been identified as important predictors of the prognosis of esophageal cancer. However, the effect of circumferential resection margin on the prognosis evaluation of esophageal cancer is still controversial, and no definite identification of circumferential resection margin of esophageal cancer has been acknowledged worldwide. Therefore, the studies of circumferential resection margin involvement in predicting the prognosis of esophageal cancer are reviewed.

Value of endorectal ultrasonography and MRI examination in the preoperative evaluation of T staging and circumferential resection margin of rectal cancer / 中华消化外科杂志

Objective To investigate the value of endorectal ultrasonography (ERUS) and MRI examination in the preoperative evaluation of T staging and circumferential resection margin (CRM) of rectal cancer.Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 193 patients [122 males and 71 females,age (60± 12)years with the range of 26-90 years] who underwent radical resection of rectal cancer at the First Hospital of Jilin University from May 2016 to January 2018 were collected.All patients underwent ERUS and MRI examination before surgery,total mesorectal excision during surgery and postoperative pathological examination.Postoperative pathological results as the gold standard,the sensitivity,specificity in T staging and the CRM diagnostic coincidence rate of rectal carcinoma by ERUS and MRI examination are evaluated.Observation indicators:(1) evaluation of T staging of rectal cancer by ERUS and MRI examination;(2) evaluation of CRM in rectal cancer by ERUS and MRI examination.Measurement data with normal distribution were represented as Mean±SD.Sensitivity,specificity and coincidence rate were calculated by chi-square test of paired fourfold table.McNemar test was used to compare the coincidence rate of T staging between ERUS and MRI examination.Consistency between CRM measurement by ERUS examination and pathological examination of rectal cancer was conducted by Kappa analysis.Fisher exact probability test was used to compare the coincidence rate of positive CRM between ERUS and MRI examination.Results (1) Evaluation of T staging of rectal cancer by ERUS and MRI examination.The overall coincidence rate of T staging of rectal cancer and coincidence rates of T1,T2,T3,T4 staging by ERUS examination were 74.61％ (144/193),93.78％ (181/193),80.83％ (156/193),79.79％ (154/193) and 94.82％ (183/193),respectively.The sensitivity ofT1,T2,T3 and T4 staging was 55.56％ (10/18),77.50％ (31/40),78.46％ (102/130),20.00％ (1/5),and the specificity was 97.71％ (171/175),81.70％ (125/153),82.54％ (52/63),96.81％ (182/188),respectively.The overall coincidence rate of T staging of rectal cancer and coincidence rates of T1,T2,T3,T4 staging by MRI examination were 50.78％ (98/193),90.67％ (175/193),74.09％ (143/193),58.55％ (113/193) and 78.24％ (151/193),respectively.The sensitivity of T1,T2,T3 and T4 staging was 0 (0/18),17.50％ (7/40),68.46％ (89/130),40.00％ (2/5),and the specificity was 100.00％ (175/175),88.89％ (136/153),38.10％ (24/63),79.26％ (149/188),respectively.There was statistically significant difference between the overall coincidence rate of ERUS and MRI examination for T staging of rectal cancer (x2 =8.631,P＜0.05).(2) Evaluation of CRM in rectal cancer by ERUS and MRI examination.The sensitivity and specificity of positive CRM evaluation of rectal cancer by ERUS examination were 100.00％ (5/5) and 97.34％ (183/188) respectively,and the coincidence rate with results of pathological examination was 97.41％ (188/193),showing a high consistency between positive CRM evaluation of rectal cancer by ERUS examination and pathological examination (Kappa value =0.655,P ＜ 0.05).The sensitivity and specificity of positive CRM evaluation of rectal cancer by MRI examination were 40.00％ (2/5) and 92.02％ (173/188),and the coincidence rate with pathological examination was 90.67％ (175/193),respectively,showing a high consistency between positive CRM evaluation of rectal cancer by MRI and pathological examination (Kappa value =0.206,P＜0.05).There were statistically significant differences in the diagnostic coincidence rate and specificity of CRM positive evaluation for rectal cancer between ERUS and MRI examination (x2 =5.896,P＜0.05).Conclusion ERUS examination has a high coincidence rate in the preoperative T staging of rectal cancer and a high consistency between positive CRM evaluation of rectal cancer with pathological examination,which are superior to MRI examination in the two aspects.

Therapeutic effect of extralevator abdominoperineal excision in combination with conventional abdominoperineal excision on distal rectal cancer:A Meta-analysis / 西安交通大学学报(医学版)

Objective To explore the short and long-term efficacy of extralevator abdominoperineal excision (ELAPE)vs.conventional abdominoperineal excision (APE)on distal rectal cancer.Methods Relevant studies were identified by search of Medline,EMBASE,and Web of Science published between January 1,2008 and February 28,2015,and included in the systematic review and meta-analysis with Stata software (version 12.0). Results Our Meta-analysis included 14 studies involving 3278 patients,of whom 1843 (56.2%)underwent ELAPE and 1435 (43.8%)underwent APE.Compared with patients undergoing APE,those undergoing ELAPE had a significantly reduced risk of intraoperative bowel perforation (IBP)involvement (OR=0 .55 ,95% CI= 0 .37-0 .85 ),but no significant reduction in the occurrence of CRM positivity (OR=0 .81 ,95% CI=0 .52-1 .25 ), local recurrence (LR)(OR=0.49,95% CI=0.18-1.30),wound complications (WCs)(OR=0.93,95% CI=0.65-1.35)or in-hospital death (IHD)(OR=0.89,95% CI=0.47-1.71).Conclusion ELAPE can reduce the risk of IBP but not for CRM positivity or LR when compared with APE.Therefore,more higher-quality studies are needed to verify the short-and long-term effects of ELAPE procedure on distal rectal cancer.

Advantage of extralevator abdominoperineal excision comparing to the conventional abdominoperineal excision for low rectal cancer: a Meta-analysis / 中南大学学报(医学版)

Objective:Whether extralevator abdominoperineal excision (ELAPE) improves survival and safety remains controversial.Systematic review of all comparative studies to define the superiority of ELAPE to conventional abdominoperineal excision (APE).Methods:Corresponding data,with case-control studies or cohorts regarding intraoperative perforation rate,the local recurrence rate and postoperative complications in the ELAPE group and the APE group,were retrieved from PubMed,Embase,the Cochrane Library,Chinese Biomedical Literature (CMB),VIP,China National Knowledge Infrastructure (CNKI),and Wanfang Database.Meta-analysis was performed by using RenMan 5.2.Results:A total of 10 articles were included.Intraperative perforation rate (MD=0.54,95％ CI 0.31 to 1.39,P=0.03),local recurrence rate (MD=0.30,95％ CI 0.21 to 0.42,P＜0.001) in the ELAPE group was significantly lower than that in the APE group.The difference in positive margin rate between the 2 groups was not statistically significant (P=0.07).Conclusion:Through gap repair of episiotomy and individualized therapy can improve ELAPE postoperative quality of life.ELAPE shows certain advantages in treating lower rectal cancer comparing to APE,but it should pay attention to individualized treatment.More studies through large sample multi-center,medium and long term randomized design are necessary to determine the effect of surgery on tumor.

Comparative study of transrectal ultrasonography and magnetic resonance in preoperative estimation of circumferential resection margin of mid-low rectal cancer / 中华超声影像学杂志

Objective To compare the value of transrectal ultrasonography(TRUS) and magnetic resonance(MR) in preoperative estimation of circumferential resection margin (CRM) of mid-low rectal cancer.Methods Both TRUS and MR were performed prior to surgery in 111 patients with mid-low rectal cancer.The CRM was evaluated and compared with the postoperative pathologic findings.Results The accuracy of TRUS and MR for CRM was 91.9％(102/111) and 85.6％(95/111),respectively,there was no statistical difference between them (P =0.137).Their specificities were 94.0％ (79/84)and 84.5％ (71/84),there was statistical difference between them(P =0.046).The consistency of the results between TRUS and pathology was better than that between MR and pathology(Kappa1 =0.783,Kappas =0.652).Conclusions TRUS is proved to have an important diagnostic value for CRM of mid-low rectal cancer.

The relationship between CD133+ cancer stem cells in circumferential resection margin and prognosis of rectal cancer / 肿瘤研究与临床

Objective To determine whether the CD133+ cancer stem cells lie in circumferential resection margin of rectal cancer,and to explore the relationship between CD133+ cancer stem cells and prognosis of rectal cancer.Methods The circumferential resection margin of rectal cancer was cut,one half of the tissue was stained HE for microscope observation.Both groups were labeled CD133 by immunohistochemistry.The tissues with positive circumferential resection margin were classified as experimental group,otherwise the control group.Another half was made into single cell suspension and used to detect CD133+ cancer stem cells by flow cytometry.The relapse of patients in the experimental group was following-up.Results Two cases were positive by immunohistochemistry in the experimental group (28 cases),showed that CD133+ cancer stem cells were in circumferential resection margin,but there was not marked difference compared with the control group (72 cases were all negative) (P =0.076).CD133+ cancer stem cells can be detected by flow cytometry,and the expression was higher in experimental group than that in the control group (5.19 ％ and 0.56 ％,Z =-7.739,P ＜ 0.01).In experimental group,the expression of CD133+ cancer stem cells in circumferential resection margin of relapse patients was significantly higher than that in patients without relapse,the difference was statistically significant [(6.57±1.72) ％ and (4.77±1.33) ％,t =3.038,P ＜ 0.05].Spearman rank correlation analysis showed that the proportion of CD133+ cancer stem cells in the experimental group was positively correlated with relapse (rs =0.473,P ＜ 0.05).Conclusion There are CD133 + cancer stem cells within circumferential resection margin of rectal cancer,and the expression of CD133+ cancer stem cells in experimental group is correlated with the postoperative recurrence.

Circumferential Resection Margin Involvement in Stage III Rectal Cancer Patients Treated with Curative Resection Followed by Chemoradiotherapy: A Surrogate Marker for Local Recurrence?

PURPOSE: Circumferential resection margin (CRM) involvement is a well-known predictor for poor prognosis in rectal cancer. However, the significance is controversial in some studies. Accordingly, this study attempted to examine the prognostic impact of CRM involvement in stage III rectal cancer. MATERIALS AND METHODS: Between January 1990 and December 2007, a total of 449 patients who underwent curative resection followed by complete adjuvant chemoradiotherapy for stage III rectal cancer located within 12 cm from the anal verge were selected. Patients were divided into a CRM-positive group (n=79, 17.6%) and a CRM-negative group (n=370, 82.4%). RESULTS: With a median follow-up of 56.6 months, recurrent disease was seen in 53.2 and 43.5% of the CRM-positive and CRM-negative group, respectively. CRM involvement was an independent prognostic factor for 5-year systemic recurrence-free survival (HR: 1.5, CI: 1.0-2.2, p=0.017). However, no significant difference was observed for local recurrence rate between the two groups (13.0 and 13.5%, respectively, p=0.677). CONCLUSION: In this study, local recurrence rate did not differ according to CRM involvement status in stage III rectal cancer patients, although CRM involvement was shown to be an independent poor prognostic factor. Accordingly, validation of the results of this study by further large prospective randomized trials is warranted.

Risk factors of circumferential resection margin involvement in the patients with extraperitoneal rectal cancer / 대한외과학회지

PURPOSE: Currently, circumferential resection margins (CRM) are used as a clinical endpoint in studies on the prognosis of rectal cancer. Although the concept of a circumferential resection margin in extraperitoneal rectal cancer differs from that in intraperitoneal rectal cancer due to differences in anatomical and biologic behaviors, previous reports have provided information on CRM involvement in all types of rectal cancer including intraperitoneal lesions. Therefore, the aim of this study was to analyze risk factors of CRM involvement in extraperitoneal rectal cancer. METHODS: From January 2005 to December 2008, 306 patients with extraperitoneal rectal cancer were enrolled in a prospectively collected database. Multivariate logistic regression analysis was used to identify predictors of CRM involvement. RESULTS: The overall rate of CRM involvement was found to be 16.0%. Multivariate analysis showed that male sex, larger tumor size (> or =4 cm), stage higher than T3, nodal metastasis, tumor perforation and non-sphincter preserving proctectomy (NSPP) were risk factors for CRM involvement. CONCLUSION: Male sex, larger tumor size (> or =4 cm), advanced T stage, nodal metastasis, tumor perforation, and NSPP are significant risk factors of CRM involvement in extraperitoneal rectal cancer. Given that postoperative chemoradiotherapy is recommended for patients with a positive CRM, further oncologic studies are warranted to ascertain which patients with these risk factors would require adjuvant therapy.

Resonancia magnética de alta resolución en el cáncer de recto / High-Resolution MRI in Rectal Cancer

La Resonancia Magnética de alta resolución (RM AR) es el mejor método para demostrar la relación del tumor rectal con el potencial margen circunferencial de resección quirúrgico. Por esta razón es considerada en la actualidad el método de elección en la estadificación local del cáncer de recto. La cirugía primaria del cáncer rectal es la escisión total del mesorrecto (ETM), cuyo plano de disección está formado por la fascia mesorrectal que envuelve la grasa del mesorrecto y al recto. Esta fascia es la que determinará el margen circunferencial de resección (MCR). Asu vez, la RM AR permite una adecuada identificación preoperatoria de importantes factores pronósticos de riesgo, mejorando la selección e indicación de la terapia para cada paciente. Esta información incluye, además del MCR, la estadificación tumoral y ganglionar, la invasión vascular extramural y la descripción de tumores de recto inferior. Todos ellos deberán ser descriptos minuciosamente en el informe, siendo parte importante de la discusión en el equipo multidisciplinario (EMD), ámbito en el cual se tomarán las decisiones que involucren al paciente con cáncer de recto. El objetivo de este trabajo es aportar la información necesaria para entender el uso de la RM AR en la identificación de los factores pronósticos de riesgo en el cáncer de recto. Se describirán los requerimientos técnicos para la realización de este estudio y el informe estandarizado, como así también los reparos anatómicos de importancia para la ETM, que como hemos dicho es la cirugía de elección en el cáncer de recto.

High-resolution MRI is the best method of assessing therelation of the rectal tumor with the potential circumferentialresection margin (CRM). Therefore it is currently considered the method of choice for local staging of rectal cancer. The primary surgery of rectal cancer is total mesorectal excision (TME), which plane of dissection is formed by the mesorectal fascia surrounding mesorectal fat and rectum. This fascia will determine the circumferential margin of resection. At the same time, high resolution MRI allows adequate pre-operative identification of important prognostic risk factors, improving the selection and indication of therapy for each patient. This information includes, besides the circumferential margin of resection, tumor and lymph node staging, extramural vascular invasion and the description of lower rectal tumors. All these should be described in detail in the report, being part of the discussion in the multidisciplinary team, the place where the decisions involving the patient with rectal cancer will take place. The aim of this study is to provide the information necessary to understand the use of high resolution MRI in the identification of prognostic risk factors in rectal cancer. The technical requirements and standardized report for this study will be describe, as well as the anatomical landmarks of importance for the total mesorectal excision (TME), as we have said is the surgery of choice for rectal cancer .

Abdominoperineal Resection in the Treatment of Locally-advanced Low Rectal Cancer: Is Preoperative Chemoradiation Advantageous?

PURPOSE: An abdominoperineal resection (APR) has a poor prognosis. However, limited studies about the prognostic factors in APR and the role of preoperative chemoradiotherapy (CRT) have been performed even though in rectal cancer, the application of preoperative CRT provides better local control compared to postoperative CRT. The aim of this study was to identify the prognostic factors and the impact of preoperative CRT in patients who undergo an APR. METHODS: A retrospective analysis was conducted with a total of 133 patients who underwent an APR, cT3, cT4, or cN(+) patients, for rectal cancer between January 1995 and October 2004. Fifty-one patients treated with preoperative CRT (Group 1) were compared with 82 APR patients treated with postoperative CRT (Group 2). Oncologic outcomes were compared between the two groups, and the clinicopathologic factors affecting the treatment outcomes were evaluated. RESULTS: The median follow-up period was 61.2 mo (range 6 to 194 mo). Circumferential margin (CRM) involvement was significantly associated with local recurrence (LR) and with disease-free survival in APR patients (P<0.001, P=0.011). The 5-yr LR rate was significantly lower in Group 1 than in Group 2 (P=0.013) in the univariate analysis, but no difference was noted in multivariate analysis (P=0.315). In Group 1, CRM involvement, tumor size, and lymph node metastasis were significantly lower than they were in Group 2 (P=0.043, P=0.003, P<0.001). CONCLUSION: For achieving adequate oncologic outcomes in APR patients, an adequate CRM should be acquired with an optimal operation. In addition, preoperative CRT would be helpful for high-risk APR patients with a threatening CRM margin, providing the benefit of tumor downstaging.

Clinicopathologic Analysis of Mesorectal Spread of Rectal Cancer with Whole Mount Section

PURPOSE: Total mesorectal excision (TME) has been widely accepted as the principal method in rectal cancer surgery and demonstrates good oncologic and functional outcome. The recurrence rate of mid-low rectal cancer surgery with TME is reported as 5~6%. Concerning local recurrence, remaining microscopic nodules in mesorectum are a major issue. In this study, we investigated mesorectal spread of tumors and exact lateral resection margin using whole mount section (WMS) to obtain correlations with other clinico-pathological variables. METHODS: 63 rectal cancer patients underwent surgery with TME and WMS at National Health Insurance Corporation Ilsan Hospital between December 2005 and October 2008. Preoperative study was made by computed tomography (CT), magnetic resonance imaging (MRI). We measured the distance from the largest cut section of the primary tumor to the nearest circumferential margin using MRI and compared them to lateral resection margins in WMS. RESULTS: Among 63 patients, the sex ratio was 1:1.17 and the median age was 62.7 years. There were 34 patients in TNM stage III (54.0%), 21 patients in stage II (33.3%) and 8 patients in stage I (12.7%). Lateral margin involvement was predicted in 4 cases pre-operatively and confirmed in 3 cases with WMS. Micrometastasis in mesorectum was detected in 6 patients (9.5%) and all were in stage III. N stage was statistically correlated with micrometastasis (P=0.016). CONCLUSION: WMS offers precise lateral resection margin and mesorectal spread of microscopic tumor nodules. WMS is best considered in stage III cancer to evaluate mesorectal micrometastasis. The mid-low rectal cancer cases with predicted lateral margin involvements using MRI should be operated on with great care.

Prognostic Analysis According to N Stage and Circumferential Resection Margin in Patients with Locally Advanced Rectal Cancer

PURPOSE: Efforts must be made to clarify the contribution of lymph node metastasis (NM) to adjuvant (chemo) radiotherapy following a curative resection for rectal cancer as the circumferential resection margin (CRM) has increasingly become a more reliable prognosticator for rectal cancer. This study examined the prognostic impact of NM on local recurrence, disease-free survival. and overall survival rates in curatively resected patients with locally advanced rectal cancer. METHODS: Two hundred two patients with locally advanced rectal cancer curatively resected in Pusan Paik Hospital from January 1995 to December 2003 were enrolled. These patients were divided into three groups according to lymph node (N) disease (N0: node negative, n=79; N1: 1-3 nodes positive, n=70; N2: > or =4 nodes positive, n=53). The potential prognostic factors, for example, T and N stage, preoperative carcinoembryonic antigen (CEA), postoperative (chemo) radiotherapy, operative methods, and several pathologic variables, were assessed among the three groups. The potential clinicopathologic factors were analyzed by using the Kaplan-Meier method, and the prognostic factors were compared in a Cox regression model. Also, we compared the oncologic results of 26 patients with a positive CRM (CMI) with those of the N1 and the N2 subgroups. RESULTS: N2 patients had an impaired 5-yr local control rate (19.1%) compared with N0 (6.8%) and N1 (11.6%, P=0.029) patients after a median follow up of 60 months (range, 6 to 156 mo). Differences in disease-free and overall survival were also significantly different statistically among the three groups (84.0% and 85.2% for N0; 54.9% and 65.1% for N1; 37.3% and 49.8% for N2; P<0.001 both). The impact of NM on the local recurrence, disease-free survival and overall survival was confirmed in the regression model for the curatively resected patients. There were no significant differences in the recurrence and the survival rates between CMI and N2 stage. CONCLUSION: NM has an independent prognostic impact on local failure and on disease-free survival and overall survival. Based on these findings, NM should be considered as an indicatior for adjuvant therapy. Although the prognostic impact of CMI is similar to that of N2, a larger prospective study is needed to clarify the prognostic association of CMI and N2.

Valor de la resonancia magnética en la evaluación del compromiso del margen de resección circunferencial en pacientes con cáncer rectal / Value of the magnetic resonance imaging in the assessment of the circumferential resection margin (CRM) in patients with rectal cancer

Propósito: Determinar si la RM puede predecir el compromiso tumoral del margen de resección circunferencial (MRC) en pacientes con cáncer de recto. Material y Métodos: Entre abril del 2005 y marzo del 2008, se evaluaron por resonancia magnética (RM), en forma consecutiva, 70 pacientes (40 M y 30 H, edad promedio de 64 años, rango de 34-78 años), con diagnóstico endoscópico y por biopsia de cáncer rectal inferior o medio. Se realizó una RM sin contraste E.V. en un equipo Siemens Avanto 1.5T, con bobina phase array de superficie. Se efectuaron secuencias con cortes finos ponderadas en T2 (TR¬-TE 4200-88, espesor de 3mm, gap 0, matriz de 256 x 256, FOV de 150x150 mm) en los planos axial, sagital y coronal. Los pacientes recibieron un enema rectal de 150 ml de glicerina previo al examen. No se realizó insuflación colónica ni administración de antiespasmódicos. Se midió la distancia más corta desde el borde del tumor hasta el MRC. Una distancia ≤ 2 mm en el plano axial se consideró como compromiso del MRC. Resultados: El MRC fue ≤ 2 mm tanto por RM como por anatomía patológica en 26 pacientes. En 8 casos, el MRC fue menor por RM que por anatomía patológica. En 32 pacientes el MRC estaba respetado por ambas metodologías diagnósticas y 4 pacientes fueron considerados positivos para compromiso del MRC en histología pero negativos por RM. La sensibilidad, especificidad, valor predictivo positivo y negativo de la RM para el compromiso tumoral del MRC fue de 86%, 80%, 76% y 88% respectivamente. Conclusión: La RM brinda información confiable del compromiso tumoral del MRC en pacientes con cáncer rectal, aportando una ayuda en la evaluación de este factor pronóstico de riesgo en pacientes previo al tratamiento quirúrgico.

Purpose: To determine whether magnetic resonance imaging (MRI) can predict tumor involvement of the circumferential resection margin (CRM) in patients with rectal cancer. Materials and methods: Between april 2005 and march 2008, 70 consecutive patients (mean age 64, range 34-78 years), 40 F and 30 M, with endoscopy and biopsy- proven middle and lower rectal cancer. Non contrast enhanced MRI was performed on a Siemens Avanto 1.5 T. A phased array coil was used and T2 weighted thin section sequences (TR/TE 4200/88, slice thickness 3mm, gap 0, matrix 256 x 256, field of view 150 x 150 mm) were performed in axial, sagittal and coronal orientations. Patients received a 150 ml glycerin enema before examination. No air insufflations or intramuscular antispasmodic was used. The shortest distance from the tumor edge to the circumferential margin was measured. A distance ≤ 2 mm, analyzed in axial slices, was considered as definition of circumferential margin involvement. Results: The CRM was 2 mm in both MRI and histopathological findings in 26 patients. In 8 cases the CRM was shorter on MRI than in histopathological sections. In 32 patients the CRM was respected in both exams and 4 patients were considered positive on histopathological findings but negative in MRI. The sensitivity, specificity, positive and negative predictive values for prediction of tumor involvement of CRM were 86%, 80%, 76% and 88%, respectively. Conclusions: MRI gives reliable information on tumor involvement of the CRM in patients with rectal cancer. This may provide accurate identification of an important prognostic risk factor in patients prior to surgical treatment.

Prognostic Significance of the Circumferential Resection Margin in Invasive T3 Rectal Cancer

PURPOSE: Because depth of invasion by T3 rectal cancer can vary according to the extent of mesorectal invasion, the prognosis for invasive T3 rectal cancer is reported to be very different from that for minimal invasive cancer. Recently, with more emphasis on circumferential resection margin (CRM) status, the T stage, rather than the N stage, seems to be a more valuable prognostic marker in rectal cancer. Therefore, the aim of this study is to determine the prognostic significance of the CRM in invasive T3 rectal cancer. METHODS: Through reviewing 324 consecutive patients with rectal cancer who underwent a curative resection between January 1995 and December 2002 at Busan Paik hospital, 195 patients with invasive T3 rectal cancer, who had not received preoperative neoadjuvant therapy were selected. The patients were classified into a negative CRM group (negative group, n=173) or a positive CRM group (positive group, n=22), and the patients were subgrouped according to the presence of lymph-node (LN) metastasis and CRM status as negative LN and negative CRM (L-/CM-), negative LN and positive CRM (L-/CM+), positive LN and negative CRM (L+/CM-) and positive LN and positive CRM (L+/CM+). All pathological specimens were re-reviewed by a single pathologist, and the distance between the most advanced edge and the outermost aspect of the specimen was re-measured by using a microscope. Local relapse rates, disease free survival, and overall survival were compared using the Kaplan- Meier method. Multivariate analyses to identify independent prognostic factors were performed using the logistic regression model. RESULTS: Local recurrence rates in the positive group and the negative group were 38.6% and 15.3%, respectively (P=0.004, log-rank test). The multiple logistic regression model demonstrated positive CRM (hazard ratio 4.4, P=0.0007) and N2 nodal status (hazard ratio 2.4, P=0.02) as predictors of local recurrence. In the subgroup analysis, the overall recurrence rates and survival rates were, respectively, 12.3% and 86.5% in the L-/CM- subgroup, 53.1% and 50.3% in the L-/CM+ subgroup, 52.7% and 50.0% in the L+/ CM- subgroup, and 58.7 % and 33.8% in the L+/CM+ subgroup (log rank test for trend; P=0.0001 and P=0.0001, respectively). CONCLUSIONS: In the event of predicted CRM involvement in invasive T3 rectal cancer, adjuvant therapy should be performed to improve local control. Also, larger prospective studies are needed to clarify the prognostic role of the CRM in invasive T3 rectal cancer because the number of cases in this study was small, especially in the number of CRM positive cases.

Prognostic Significance of Circumferential Resection Margin following a Total Mesorectal Excision in Rectal Cancer

PURPOSE: Studies of the circumferential resection margin (CRM) in rectal cancer surgery have revealed that inadequate surgical excision correlates with a high risk of recurrence. This study was designed to evaluate the prognostic value of the CRM in rectal cancer. METHODS: All 504 patients who underwent a total mesorectal excision for rectal cancer between 1997 and 2001 were studied. The distance between the CRM and the tumor on pathology slides (HE stain, x 20 times) was measured. The CRM was stained by using the Davidson marking system(R) (Bradley Product, Inc. USA), and a micrometer was used for the measurement. We divided the patients into a negative CRM group (CRM >3 mm), an abutting CRM group (CRM 3 mm), 5.6%, 38.9%, and 5.6% in the abutting CRM group, and 8.8%, 44.1%, and 8.8% in the positive CRM group. The five-year survival rates for the negative CRM, the abutted CRM and the positive CRM groups were 73.3%, 48.4%, and 25.5% (P<0.001), respectively, and the disease-free 5-year survival rates were 63.1%, 30.6%, 24.0% (P<0.001). The CRM was shown to be an independent prognostic factor by multivariate analyses adjusted for known predictors of outcome (P<0.001). CONCLUSIONS: The prognosis for a member of the abutting or the positive CRM group was more unfavorable than it was for a member of the negative CRM group; therefore, measurement of the CRM should be reported in the pathologic report. For patients with an abutting or a positive CRM, neoadjuvant or adjuvant chemoradiotherapy should be considered for better oncologic outcomes.

Significance of Circumferential Resection Margin Involvement Following Esophagectomy for Esophageal Cancer

BACKGROUND: This study was performed to examine the significance of the circumferential resection margin (CRM) involvement by a tumor on the postoperative survival after esophageal cancer surgery. METHODS: Fifty nine resected cases of esophageal cancers were retrospectively reviewed. The presence of a tumor either at, or within 1 mm of, the CRM was recorded. By an immunohistochemical study for Ki-67, the Ki-67 differential grades (Ki-67 DG) were defined according to the differences between the Ki-67 labeling indices of the central and of peripheral areas of the tumor nearest to the CRM: Ki-67 DG 0 (10%). The CRM involvement was correlated with the clinicopathological factors, Ki-67 DG and survival data. RESULTS: CRM involvement was found in 26 (44.1%) of the 59 cases. There were significant differences in the cases, both with and without CRM involvement of tumor cells, in relation to lymph node metastasis, lymphovascular, perineural invasions and tumor stage (p<0.05). Ten (38.3%) of the 26 with, and 3 (9.1%) of 33 cases without, CRM involvement, showed Ki-67 DG 1 (p=0.007). The 3-year survivals of patients with and without CRM involvement were 26.8 and 61.8%, respectively (p=0.003). CONCLUSIONS: These results show that the CRM involvement status may be used as a predictor of survival after esophageal cancer surgery, and CRM involvement is more an indicator of an advanced disease than of an incomplete resection.