Lymph Node Dissection Using Bipolar Vessel-Sealing Device During Reduced Port Laparoscopic Distal Gastrectomy for Gastric Cancer: Result of a Pilot Study from a Single Institute.

INTRODUCTION: The electrothermal bipolar vessel-sealing device (BVSD) is known to supply a strong vessel-sealing power. However, only few studies have reported lymph node dissection (LND) using only BVSD during laparoscopic surgery for gastric cancer. The purpose of this study was to investigate the feasibility of LND using BVSD during reduced port laparoscopic distal gastrectomy for gastric cancer. METHODS: From May 2015, patients in whom three- or single-port laparoscopic distal gastrectomy had been engaged for gastric cancer were enrolled in this study. We performed D1+ or D2 LND using only LigaSure™ Maryland (Medtronics, Minneapolis, MN), a recently developed BVSD. Clinical outcomes of these patients were investigated. RESULTS: From May 2015 to November 2016, 20 patients were enrolled in this study. The mean operation time was 262.6 ± 36.6 (200-340) minutes. The mean time for LND was 124.7 ± 19.2 (93-171) minutes. Only one patient had a morbidity of Clavien-Dindo grade more than II. No mortality was observed in all patients. The mean number of retrieved lymph nodes was 46.8 ± 22.8 (15-105). CONCLUSIONS: LND using the Maryland jaw type BVSD was feasible during reduced port (single- or three-port) laparoscopic distal gastrectomy for gastric cancer. Objectively evaluating the potential advantages of BVSD in reduced port laparoscopic surgery is necessary.

A comparison between two methods for tumor localization during totally laparoscopic distal gastrectomy in patients with gastric cancer.

PURPOSE: The aim of this study was to compare two methods of tumor localization during totally laparoscopic distal gastrectomy (TLDG) in patients with gastric cancer. METHODS: From March 2014 to November 2014, patients in whom TLDG had been engaged for middle third gastric cancer enrolled in this study. The patients were allocated to either the radiography or endoscopy group based on the type of tumor localization technique. Clinicopathologic outcomes were compared between the 2 groups. RESULTS: The accrual was suspended in November 2014 when 39 patients had been enrolled because a failed localization happened in the radiography group. The radiography and endoscopy groups included 17 (43.6 %) and 22 patients (56.4 %), respectively. Mean length of the proximal resection margin did not differ between the radiography and endoscopy groups (4.0 ± 2.6 and 2.8 ± 1.2 cm, respectively; P = 0.077). Mean localization time was longer in the radiography group than in the endoscopy group (22.7 ± 11.4 and 6.9 ± 1.8 minutes, respectively, P < 0.001). There were no statistically significant differences in the incidence of severe complications between the 2 groups (5.9% and 4.5%, respectively, P = 0.851). CONCLUSION: As an intraoperative tumor localization for TLDG, radiologic method was unsafe even though other comparable parameters were not different from that of endoscopy group. Moreover, intraoperative endoscopic localization may be advantageous because it is highly accurate and contributes to reducing operation time.

Occupational stress and related factors among surgical residents in Korea.

PURPOSE: The application rate for surgical residents in Korea has continuously decreased over the past few years. The demanding workload and the occupational stress of surgical training are likely causes of this problem. The aim of this study was to investigate occupational stress and its related factors in Korean surgical residents. METHODS: With the support of the Korean Surgical Society, we conducted an electronic survey of Korean surgical residents related to occupational stress. We used the Korean Occupational Stress Scale (KOSS) to measure occupational stress. We analyzed the data focused on the stress level and the factors associated with occupational stress. RESULTS: The mean KOSS score of the surgical residents was 55.39, which was significantly higher than that of practicing surgeons (48.16, P < 0.001) and the average score of specialized professionals (46.03, P < 0.001). Exercise was the only factor found to be significantly associated with KOSS score (P = 0.001) in univariate analysis. However, in multiple linear regression analysis, the mean number of assigned patients, resident occupation rate and exercise were all significantly associated with KOSS score. CONCLUSION: Surgical residents have high occupational stress compared to practicing surgeons and other professionals. Their mean number of assigned patients, resident recruitment rate and exercise were all significantly associated with occupational stress for surgical residents.

Lessons learned from a comparative analysis of surgical outcomes of and learning curves for laparoscopy-assisted distal gastrectomy.

PURPOSE: Before expanding our indications for laparoscopic gastrectomy to advanced gastric cancer and adopting reduced port laparoscopic gastrectomy, we analyzed and audited the outcomes of laparoscopy-assisted distal gastrectomy (LADG) for adenocarcinoma; this was done during the adoptive period at our institution through the comparative analysis of short-term surgical outcomes and learning curves (LCs) of two surgeons with different careers. MATERIALS AND METHODS: A detailed comparative analysis of the LCs and surgical outcomes was done for the respective first 95 and 111 LADGs performed by two surgeons between July, 2006 and June, 2011. The LCs were fitted by using the non-linear ordinary least squares estimation method. RESULTS: The postoperative morbidity and mortality rates were 14.6% and 0.0%, respectively, and there was no significant difference in the morbidity rates (12.6% vs. 16.2%, P=0.467). More than 25 lymph nodes were retrieved by each surgeon during LADG procedures. The LCs of both surgeons were distinct. In this study, a stable plateau of the LC was not achieved by both surgeons even after performing 90 LADGs. CONCLUSIONS: Regardless of the experience with gastrectomy or laparoscopic surgery for other organs, or the age of surgeon, the outcome was quite acceptable; the learning process differ according to the surgeon's experience and individual characteristics.

High occupational stress and low career satisfaction of Korean surgeons.

Surgery is a demanding and stressful field in Korea. Occupational stress can adversely affect the quality of care, decrease job satisfaction, and potentially increase medical errors. The aim of this study was to investigate the occupational stress and career satisfaction of Korean surgeons. We have conducted an electronic survey of 621 Korean surgeons for the occupational stress. Sixty-five questions were used to assess practical and personal characteristics and occupational stress using the Korean occupational stress scale (KOSS). The mean KOSS score was 49.31, which was higher than the average of Korean occupational stress (45.86) or that of other specialized professions (46.03). Young age, female gender, long working hours, and frequent night duties were significantly related to the higher KOSS score. Having spouse, having hobby and regular exercise decreased the KOSS score. Multiple linear regression analysis showed that long working hours and regular exercise were the independent factors associated with the KOSS score. Less than 50% of surgeons answered that they would become a surgeon again. Most surgeons (82.5%) did not want to recommend their child follow their career. Korean Surgeons have high occupational stress and low level of career satisfaction.

Should lymph node micrometastasis be considered in node staging for gastric cancer?: the significance of lymph node micrometastasis in gastric cancer.

BACKGROUND: In TNM staging system, lymph node staging is based on the number of metastatic lymph nodes in gastric cancer and micrometastasis is not considered. Several reports proposed the importance of lymph node micrometastasis as the causative factor for recurrence and poor survival, but it remains controversial among researchers. METHODS: A total of 482 gastric cancer patients who underwent curative resection from 2004 to 2010 at Korea University Medical Center Ansan Hospital, South Korea were prospectively enrolled. For detecting lymph node micrometastasis, immunohistochemical staining with anti-cytokeratin antibody (CAM 5.2) was performed on negative lymph nodes by hematoxylin-eosin (H-E) staining. Survival differences were compared between conventional node staging and new node staging that took micrometastasis into consideration. Also, the prognostic value of lymph node micrometastasis was investigated in multivariate analysis. RESULTS: A total of 156 patients (32.4%) showed lymph node micrometastasis. Overall, the micrometastatic group had more advanced tumor and lymph node stage, lymphovascular cancer cell invasion, a higher rate of recurrence, and poor survival. Furthermore, when the cumulative numbers of macro- and micrometastatic lymph nodes were calculated together, the discriminative power of survival difference between each node stage became more stratified. Also, multivariate analysis using Cox's proportional hazards model demonstrated perineural invasion, pathologic T stage, dissected lymph nodes, macro- and micrometastatic lymph nodes are independent prognostic factors. CONCLUSIONS: Lymph node micrometastasis was clinically significant as a risk factor for recurrent gastric cancer. Lymph node micrometastasis should be considered when estimating TNM stage for determining prognosis and the best treatment strategy.

Gastrectomy for the treatment of refractory gastric ulceration after radioembolization with 90Y microspheres.

Transcatheter arterial radioembolization (TARE) with Yttrium-90 ((90)Y)-labeled microspheres has an emerging role in treatment of patients with unresectable hepatocellular carcinoma. Although complication of TARE can be minimized by aggressive pre-evaluation angiography and preventive coiling of aberrant vessels, radioembolization-induced gastroduodenal ulcer can be irreversible and can be life-threatening. Treatment of radioembolization-induced gastric ulcer is challenging because there is a few reported cases and no consensus for management. We report a case of severe gastric ulceration with bleeding that eventually required surgery due to aberrant deposition of microspheres after TARE.

Primary gastric malignant melanoma mimicking adenocarcinoma.

We report a case of primary gastric malignant melanoma that was diagnosed after curative resection but initially misdiagnosed as adenocarcinoma. A 68-year-old woman was referred to our department for surgery for gastric adenocarcinoma presenting as a polypoid lesion with central ulceration located in the upper body of the stomach. The preoperative diagnosis was confirmed by endoscopic biopsy. We performed laparoscopic total gastrectomy, and the final pathologic evaluation led to the diagnosis of primary gastric malignant melanoma without a primary lesion detected in the body. To the best of our knowledge, primary gastric malignant melanoma is extremely rare, and this is the first case reported in our country. According to the literature, it has aggressive biologic activity compared with adenocarcinoma, and curative resection is the only promising treatment strategy. In our case, the patient received an early diagnosis and underwent curative gastrectomy with radical lymphadenectomy, and no recurrence was noted for about two years.

The significance of mismatch repair genes in gastric cancer.

BACKGROUND: Microsatellite instability (MSI) is a form of genetic instability characterized by new alleles not present in the normal genotype. This mutation occurs by altered DNA mismatch repair (MMR) genes. Studies of limited numbers of patients have reported conflicting results regarding the association of the MSI phenotype with gastric cancer. This study aims to evaluate the clinical significance of mismatch repair genes in gastric cancer. MATERIALS AND METHODS: We studied 156 gastric cancer patients who underwent gastrectomy from March 2010 to February 2011 in our hospital. Mismatch repair status was determined by the immunohistochemical analysis of human MutL Homolog 1 (hMLH1) and human MutS Homolog 2 (hMSH2) expression. RESULTS: Seventeen (10.9%) cases did not express hMLH1 but all cases expressed hMSH2. In univariate analyses, the expression of hMLH1 was associated with age, nodal status, and Lauren's classification. In multivariate analyses, there was no statistically significant association between the loss of hMLH1 expression and selected clinical parameters. CONCLUSION: The expression of hMLH1 was associated with age, nodal status, and Lauren's classification. Our results suggest that MMR gene abnormalities play an important role in the tumorigenesis of patients demonstrating gastric cancer.

Impact of age and comorbidity on the short-term surgical outcome after laparoscopy-assisted distal gastrectomy for adenocarcinoma.

The aim of this study was to determine whether age and comorbidity are valuable risk factors of the short-term surgical outcome after laparoscopy-assisted distal gastrectomy (LADG) in patients with adenocarcinoma. A series of 387 patients who underwent LADG at three university hospitals between March 2006 and December 2010 were retrospectively studied. To compare the short-term surgical outcomes of LADG of elderly patients with those of younger patients, patients were categorized into an elderly group (older than 70 years of age) and a younger group (70 years of age or younger). For another comparative analysis to identify risk factors of postoperative complications after LADG, patients were categorized into two groups: those with complications and those without complications. With the exception of sex ratio and comorbidity rate, two age groups were nonsignificantly different in terms of demographic, operative, pathologic, and short-term surgical outcome data. Our data support the safety and feasibility of LADG in elderly patients. However, our data show that comorbidity is an important predictor of postoperative systemic complications after LADG. Patients with an age-adjusted Charlson comorbidity index (CCI) of 3 or greater were found to be at a greater risk of developing systemic complications, which suggests that age-adjusted CCI is a useful predictor of systemic complications after LADG and that it could be used routinely for the perioperative care of aged patients with comorbidity. We recommend age-adjusted CCI be used in comparative clinical research studies on the surgical outcomes across surgeons and hospitals.

Expression of intercellular adhesion molecule-1 and e-selectin in gastric cancer and their clinical significance.

PURPOSE: Among cell adhesion molecules, serum levels of intercellular adhesion molecule-1 and E-selectin are known to be correlated with the metastatic potential of gastric cancer. In the present study, the authors investigated the expression of intercellular adhesion molecule-1 and E-selectin in gastric cancer tissues and cultured gastric cancer cells, and examined their clinical value in gastric cancer. MATERIALS AND METHODS: The protein was extracted from gastric cancer tissues and cultured gastric cancer cells (MKN-28 and Kato-III) and the expression of intercellular adhesion molecule-1 and E-selectin was examined by western blotting. The clinical significance of intercellular adhesion molecule-1 and E-selectin was explored, using immunohistochemical staining of specimens from 157 gastric cancer patients. RESULTS: In western blot analysis, the expressions of intercellular adhesion molecule-1 in gastric cancer tissues and cultured gastric cancer cells were increased, however, E-selectin in gastric cancer tissues and cells were not increased. Among 157 gastric cancer patients, 79 patients (50%) were intercellular adhesion molecule-1 positive and had larger tumor size, an increased depth of tumor invasion, lymph node metastasis and perineural invasion. The intercellular adhesion molecule-1 positive group showed a higher incidence of tumor recurrence (40.5%), and a poorer 3-year survival than the negative group (54.9 vs. 85.9%, respectively). CONCLUSIONS: Intercellular adhesion molecule-1 is overexpressed in gastric cancer tissues and cultured gastric cancer cells, whereas E-selectin is not overexpressed. Increased expression of intercellular adhesion molecule-1 in gastric cancer could be related to the aggressive nature of the tumor, and has a poor prognostic effect on gastric cancer.

Expression of estrogen receptors in gastric cancer and their clinical significance.

BACKGROUNDS AND OBJECTIVES: The male predominance of gastric cancer suggests that female sex hormones may have a protective effect against gastric cancer. We evaluated the expression of estrogen receptors in gastric cancer tissue and cells and the clinical significance of ER-ß expression in gastric cancer. METHOD: ER-α, ER-ß proteins extracted from normal stomach, gastric cancer tissues, and cultured gastric cancer cells (KATO-III, mkn28, mkn45, and mkn74) were assessed by Western blot analysis. The clinical significance of ER-ß was explored using tissue microarray methods and immunohistochemical staining of specimens from 148 gastric cancers. RESULTS: Both ER-α and ß protein expression were noted in normal and gastric cancer tissues. However, in cultured gastric cells, only ER-ß was noted in mkn28 and mkn74. Of 148 gastric cancers, 67 (45.3%) were ER-ß positive. The ER-ß positive group was associated with lower tumor stage, Lauren's intestinal type, negative perineural invasion, and free of recurrence. The ER-ß positive group had a better 3-year survival compared with the negative group in survival analysis. CONCLUSION: Our results suggest that the presence of ER-ß in gastric cancer could have a protective effect against invasiveness of gastric cancer. Further studies are needed to clarify the role of ER-ß in gastric cancers.

Clinical significance of the pattern of lymph node metastasis depending on the location of gastric cancer.

PURPOSE: When performing a laparoscopic assisted gastrectomy, a function-preserving gastrectomy is performed depending on the location of the primary gastric cancer. This study examined the incidence of lymph node metastasis by the lymph node station number by tumor location to determine the optimal extent of the lymph node dissection. MATERIALS AND METHODS: The subjects consisted of 1,510 patients diagnosed with gastric cancer who underwent a gastrectomy between 1996 and 2005. The patients were divided into three groups: upper, middle and lower third, depending on the location of the primary tumor. The lymph node metastasis patterns were analyzed in the total and early gastric cancer patients. RESULTS: In all patients, lymph node station numbers 1, 2, 3, 7, 10 and 11 metastases were dominant in the cancer originating in the upper third, whereas station numbers 4, 5, 6 and 8 were dominant in the lower third. In early gastric cancer patients, the station number of lymph nodes with a metastasis did not show a significant difference in stage pT1a disease. On the other hand, a metastasis in lymph node station number 6 was dominant in stage pT1b disease that originated in the lower third of the stomach. CONCLUSIONS: When performing a laparoscopic-assisted gastrectomy for early gastric cancer, a limited lymphadenectomy is considered adequate during a function-preserving gastrectomy in mucosal (T1a) cancer. On the other hand, for submucosal (T1b) cancer, a number 6 node dissection should be performed when performing a pylorus preserving gastrectomy.

Clinical Outcomes of Gastrectomy after Incomplete EMR/ESD.

PURPOSE: Endoscopic resection is widely accepted as standard treatment for early gastric cancer (EGC) without lymph node metastasis. The procedure is minimally invasive, safe, and convenient. However, surgery is sometimes needed after endoscopic mucosal resection (EMR)/endoscopic submucosal dissection (ESD) due to perforation, bleeding, or incomplete resection [corrected]. We evaluated the role of surgery after incomplete resection. MATERIALS AND METHODS: We retrospectively studied 29 patients with gastric cancer who underwent a gastrectomy after incomplete EMR/ESD from 2006 to 2010 at Korea University Hospital. RESULTS: There were 13 incomplete resection cases, seven bleeding cases, three metachronous lesion cases, three recurrence cases, two perforation cases, and one lymphatic invasion case. Among the incomplete resection cases, a positive vertical margin was found in 10, a positive lateral margin in two, and a positive vertical and lateral margin in one case. Most cases (9/13) were diagnosed as mucosal tumors by endoscopic ultrasonography, but only three cases were confirmed as mucosal tumors on final pathology. The positive residual tumor rate was two of 13. The lymph node metastasis rate was three of 13. All lymph node metastasis cases were submucosal tumors with positive lymphatic invasion and no residual tumor in the gastrectomy specimen. No cases of recurrence were observed after curative resection. CONCLUSIONS: A gastrectomy is required for patients with incomplete resection following EMR/ESD due to the risk of residual tumor and lymph node metastasis.

Metastatic lymph node targeted chemosensitivity test for gastric cancer.

BACKGROUND: The objective of this study was to compare the chemosensitivity of primary tumor and metastasized lymph node from patient with gastric adenocarcinoma. MATERIALS AND METHODS: We studied 26 gastric cancer patients with lymph node metastasis who underwent gastric resection at the Korea University Guro Hospital from Feb 2007 to July 2008. The chemosensitivity of primary tumor and metastatic lymph node were studied using an adenosine triphosphate-based chemotherapy response assay (ATP-CRA). RESULTS: The concordance rate of the ATP-CRA test was 30.8% (8/26). The concordance rate between primary tumor and metastatic N2 group lymph node was only 9.1% (1/11). The metastatic tumor inhibition rates with 5-fluorouracil, cisplatin, doxorubicin, and oxaliplatin were higher than the inhibition rates for primary tumor. Tumor inhibition rates was significantly different between primary tumor and metastatic tumor after doxorubicin treatment (27.734±20.95 versus 38.403±26.87, P=0.021). We detected simple correlations of tumor inhibition rates between primary and metastatic tumors with cisplatin (r=0.661, P<0.001) and doxorubicin (r=0.475, P=0.031). CONCLUSIONS: We observed differences between first choice chemotherapeutic agents based on ATPCRA tests of primary tumor and metastatic tumor in lymph node. Therefore, chemotherapeutic agents should be carefully selected for adjuvant chemotherapy using a chemosensitivity test.

Aging over 70 Years Is Not a Decisively Dismal Prognostic Factor in Gastric Cancer Surgery.

PURPOSE: Gastric cancer has a high incidence and mortality rate in Korea. Despite a growing older population and an increase in the number of older patients with gastric cancer, the older patients are not willing to undergo surgery due to their operative risks. Hence, to determine the clinical characteristics and outcomes of gastric cancer surgery for them, we investigate factors influencing the treatment decision. MATERIALS AND METHODS: Between January 1996 and December 2005, a total of 1,519 patients were classified into two groups; the younger age group between 41 and 69 years of age, and the older age group of 70 years or older. The analysis conducted included patient characteristics, accompanying disorders, related American Society of Anesthesiologists (ASA) grade, pathological characteristics and survival rate for each age group. RESULTS: Significant differences were found in the ASA grade (P<0.001) and the number of accompanying disorders (P<0.001) between the two groups. The average length of hospital stay after surgery was 14.5 days in the younger age group, and 13.3 days in the older age group (P=0.065). The average survival time was 47.5 months in the younger age group, and 43.2 months in the older age group (P<0.001). CONCLUSIONS: This study demonstrated that there was more number of accompanying disorders with a high surgical risk in the older age group. However, there was no significant difference between the older and younger age groups in terms of the incidence of complications, under the given disease conditions and if proper management was provided.

Laparoscopic resection of small gastric submucosal tumors.

BACKGROUND: No consensus exists regarding the necessity of operative resection for patients with small, asymptomatic gastric submucosal tumors (SMTs). The purpose of this study is to evaluate clinical outcomes of resection by minimally invasive surgery. METHODS: The medical records of 20 consecutive patients who had undergone laparoscopic or robotic wedge resection for small (<5 cm) gastric SMTs between March 2008 and February 2009 were reviewed. Operative indications included all SMTs unquestionably visible by endoscopy, irrespective of symptoms. The operative procedures, clinicopathologic features, and operative results were assessed. RESULTS: Out of a total of 20 patients, 17 were asymptomatic, and 3 presented with vague abdominal discomfort. One patient had two tumors, therefore 21 total lesions were resected and evaluated (19 by laparoscopy and 2 by robotic procedures). There were 12 exogastric and 9 transgastric wedge resections. Mean operative time was 84 ± 28 min, and mean length of hospitalization was 4.7 ± 1.6 days. There were no major peri- or postoperative complications or mortalities. Mean tumor size was 2.4 ± 1.2 cm (range 0.6-4.8 cm). All lesions had microscopically negative resection margins. There were 16 gastrointestinal tumors (GISTs) and 5 other benign lesions. Fifteen of the GISTs had mitotic count (MC) <5 per 50 high-power fields (HPFs), and one lesion measuring 2.5 cm in size had MC of 38 per 50 HPFs. CONCLUSIONS: Small size cannot guarantee a specific malignant risk for gastric SMTs. Laparoscopic/robotic wedge resection is safe and effective in treating small, asymptomatic lesions. Therefore, an active surgical approach should be considered for management of patients with small gastric SMTs.

Surgeon subspecialty as a factor in improving long-term outcomes for gastric cancer: Twenty years of experience in Korea.

BACKGROUND: The results of gastric cancer treatment have improved during the past 2 decades. In addition to early diagnosis, surgeon experience and subspecialty may influence long-term outcomes. This study analyzed data accumulated during the past 20 years regarding the impact of surgical subspecialty on gastric cancer prognosis. DESIGN: A 20-year, retrospective study. SETTING: Korea University Guro Hospital, Seoul. PATIENTS: A total of 2797 patients admitted between 1984 and 2003 with surgically treated, pathologically confirmed, primary gastric adenocarcinoma. MAIN OUTCOME MEASURE: Long-term survival. RESULTS: The incidence of total gastrectomy and the number of retrieved lymph nodes increased during the study period. In curative cases, 5-year survival improved from 66.1% to 76.6%, and this survival gain was restricted to stages I, III, and IV. A Cox proportional hazards regression model showed that age, sex, tumor location, type of resection, stage, and the interaction between period of study and surgical subspecialty were independent prognostic factors. CONCLUSIONS: This large, long-term cohort study demonstrates that the management of gastric cancer has been largely successful, with favorable trends in prognostic factors. Successful outcomes are realized more often by gastric surgical specialists. Efforts must be made to improve the treatment of patients with stage II gastric cancer because the improvements in long-term results have plateaued.

Advanced gastric cancer in the middle one-third of the stomach: Should surgeons perform total gastrectomy?

BACKGROUND AND OBJECTIVES: To determine which optimal surgical procedure for middle-third advanced gastric cancer (AGC) based on comparative study of the long-term prognosis between total gastrectomy (TG) and distal gastrectomy (DG). METHODS: Between March 1993 and December 2005, 402 patients with middle-third AGC who underwent gastric resection were enrolled in this study. We analyzed the long-term prognosis according to the length of the proximal resection margin (PRM) and the extent of gastric resection, and determined independent prognostic factors. RESULTS: TG was performed in 244 patients (60.7%) and DG was performed in 158 patients (39.3%). There were no significant differences in the 5-year survival rates according to the length of PRM. The 5-year survival rates of patients who underwent DG were significantly higher than the rates of the patients who underwent TG in curative cases (67.8% vs. 58.4%, P = 0.037). Nevertheless, there was no significant difference in the stage-stratified survival rates according to the extent of gastric resection. Multivariate analysis revealed that surgical curability, extent of lymphadenectomy, and stage were independent prognostic factors. CONCLUSION: If curative resection can be performed, the long-term prognosis of patients with middle-third AGC was not affected by the length of PRM or the extent of gastric resection.

Clinical significance of immunohistochemically-identified lymphatic and/or blood vessel tumor invasion in gastric cancer.

BACKGROUND: Tumor invasion and lymph node metastasis are significant prognostic factors for gastric cancer, and lymphatic and vascular tumor invasion are also significant risk factors for gastric cancer recurrence. Recently, the immunohistochemical detection of lymphatic and blood vessel tumor invasion (LBVI) has been shown to have a higher sensitivity and specificity than hematoxylin-eosin staining methods. MATERIALS AND METHODS: One hundred forty-nine gastric cancer patients who underwent curative resection at Korea University Hospital between November 2003 and December 2006 served as the study subjects. Lymphatic vessel invasion was evaluated by immunostaining with the new selective marker, D2-40, and blood vessel invasion was assessed with anti-CD31 antibody. Patients were divided according to the presence of LBVI, clinicopathologic factors were compared, and postoperative surgical outcomes were analyzed. RESULTS: LBVI was present in 66 patients (44.3%). LBVI was significantly correlated with depth of tumor invasion (P < 0.001), lymph node stage (P < 0.001), and lymph node micrometastasis (P = 0.013). Cancer recurrence was more common in the LBVI group (P = 0.007), and peritoneal seeding was the most prevalent type of recurrence (P = 0.028). Univariate analysis showed tumor size, depth of tumor invasion, lymph node stage, and LBVI to have a significant impact on survival. Based on multivariate analysis, however, depth of tumor invasion and lymph node stage were correlated with survival. CONCLUSION: Immunohistochemical demonstration of LBVI is an additional prognostic marker, and provides useful information for planning treatment strategies in gastric cancer patients.