Prediction of Microsatellite Instability in Colorectal Cancer Using a Machine Learning Model Based on PET/CT Radiomics

Purpose@#We investigated the feasibility of preoperative 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/ computed tomography (CT) radiomics with machine learning to predict microsatellite instability (MSI) status in colorectal cancer (CRC) patients. @*Materials and Methods@#Altogether, 233 patients with CRC who underwent preoperative FDG PET/CT were enrolled and divided into training (n=139) and test (n=94) sets. A PET-based radiomics signature (rad_score) was established to predict the MSI status in patients with CRC. The predictive ability of the rad_score was evaluated using the area under the receiver operating characteristic curve (AUROC) in the test set. A logistic regression model was used to determine whether the rad_score was an independent predictor of MSI status in CRC. The predictive performance of rad_score was compared with conventional PET parameters. @*Results@#The incidence of MSI-high was 15 (10.8%) and 10 (10.6%) in the training and test sets, respectively. The rad_score was constructed based on the two radiomic features and showed similar AUROC values for predicting MSI status in the training and test sets (0.815 and 0.867, respectively; p=0.490). Logistic regression analysis revealed that the rad_score was an independent predictor of MSI status in the training set. The rad_score performed better than metabolic tumor volume when assessed using the AUROC (0.867 vs. 0.794, p=0.015). @*Conclusion@#Our predictive model incorporating PET radiomic features successfully identified the MSI status of CRC, and it also showed better performance than the conventional PET image parameters.

Clinical Significance of Combining Preoperative and Postoperative Albumin-Bilirubin Score in Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Albumin-bilirubin (ALBI) score is a well-known prognostic factor for various diseases, including colorectal cancer (CRC). However, little is known about the significance of postoperative ALBI score changes in patients with CRC. @*Materials and Methods@#A total of 723 patients who underwent surgery were enrolled. Preoperative ALBI (ALBI-pre) and postoperative ALBI (ALBI-post) scores were divided into low and high score groups. ALBI-trend was defined as a combination of four groups comprising the low and high ALBI-pre and ALBI-post score groups. Kaplan-Meier survival curves were used to compare the overall survival (OS) between the different ALBI groups. The Cox proportional hazards model was used to examine the independent relevant factors of OS. Stratification performance was compared between the different ALBI groupings using Harrell’s concordance index (C-index). @*Results@#ALBI-pre, ALBI-post, and ALBI-trend score groups were significant prognostic factors of OS in the univariable analysis. However, multivariable analysis showed that ALBI-trend was an independent prognostic factor while ALBI-pre and ALBI-post were not. The C-index of ALBI-trend (0.622; 95% confidence interval [CI], 0.587 to 0.655) was higher than that of ALBI-pre (0.589; 95% CI, 0.557 to 0.621; bootstrap mean difference, 0.033; 95% CI, 0.013 to 0.057) and ALBI-post (0.575; 95% CI, 0.545 to 0.605; bootstrap mean difference, 0.047; 95% CI, 0.024 to 0.074). @*Conclusion@#Combining ALBI-pre and ALBI-post scores is an independent prognostic factor of OS and shows superior predictive power compared to ALBI-pre or ALBI-post alone in patients with CRC.

Machine Learning Model for Predicting Postoperative Survival of Patients with Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Machine learning (ML) is a strong candidate for making accurate predictions, as we can use large amount of data with powerful computational algorithms. We developed a ML based model to predict survival of patients with colorectal cancer (CRC) using data from two independent datasets. @*Materials and Methods@#A total of 364,316 and 1,572 CRC patients were included from the Surveillance, Epidemiology, and End Results (SEER) and a Korean dataset, respectively. As SEER combines data from 18 cancer registries, internal validation was done using 18-Fold-Cross-Validation then external validation was performed by testing the trained model on the Korean dataset. Performance was evaluated using area under the receiver operating characteristic curve (AUROC), sensitivity and positive predictive values. @*Results@#Clinicopathological characteristics were significantly different between the two datasets and the SEER showed a significant lower 5-year survival rate compared to the Korean dataset (60.1% vs. 75.3%, p < 0.001). The ML-based model using the Light gradient boosting algorithm achieved a better performance in predicting 5-year-survival compared to American Joint Committee on Cancer stage (AUROC, 0.804 vs. 0.736; p < 0.001). The most important features which influenced model performance were age, number of examined lymph nodes, and tumor size. Sensitivity and positive predictive values of predicting 5-year-survival for classes including dead or alive were reported as 68.14%, 77.51% and 49.88%, 88.1% respectively in the validation set. Survival probability can be checked using the web-based survival predictor (http://colorectalcancer.pythonanywhere.com). @*Conclusion@#ML-based model achieved a much better performance compared to staging in individualized estimation of survival of patients with CRC.

LASSO-Based Machine Learning Algorithm for Prediction of Lymph Node Metastasis in T1 Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The role of tumor-infiltrating lymphocytes (TILs) in predicting lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC) remains unclear. Furthermore, clinical utility of a machine learning–based approach has not been widely studied. @*Materials and Methods@#Immunohistochemistry for TILs against CD3, CD8, and forkhead box P3 in both center and invasive margin of the tumor were performed using surgically resected T1 CRC slides. Three hundred and sixteen patients were enrolled and categorized into training (n=221) and validation (n=95) sets via random sampling. Using clinicopathologic variables including TILs, the least absolute shrinkage and selection operator (LASSO) regression model was applied for variable selection and predictive signature building in the training set. The predictive accuracy of our model and the Japanese criteria were compared using area under the receiver operating characteristic (AUROC), net reclassification improvement (NRI)/integrated discrimination improvement (IDI), and decision curve analysis (DCA) in the validation set. @*Results@#LNM was detected in 29 (13.1%) and 12 (12.6%) patients in training and validation sets, respectively. Nine variables were selected and used to generate the LASSO model. Its performance was similar in training and validation sets (AUROC, 0.795 vs. 0.765; p=0.747). In the validation set, the LASSO model showed better outcomes in predicting LNM than Japanese criteria, as measured by AUROC (0.765 vs. 0.518, p=0.003) and NRI (0.447, p=0.039)/IDI (0.121, p=0.034). DCA showed positive net benefits in using our model. @*Conclusion@#Our LASSO model incorporating histopathologic parameters and TILs showed superior performance compared to conventional Japanese criteria in predicting LNM in patients with T1 CRC.

A surgical hospitalist system in Korea: a preliminary study of the effects on hospital costs and postoperative outcomes

Purpose@#The aim of this study is to investigate the effect of the surgical hospitalist system on postoperative outcomes and hospital costs for surgical patients. @*Methods@#We reviewed the medical records of 522 patients who were admitted to the divisions of colorectal and gastrointestinal surgery for operation from September to December 2017 at Severance Hospital, Yonsei University College of Medicine in Seoul, Korea. All patients were divided into 2 groups; one that was managed by surgical hospitalists group (HG) and another that was managed by non-hospitalist residents group (NHG) after elective surgery. Postoperative outcomes and hospital costs were analyzed for each group. @*Results@#Two hundred ninety-eight patients were managed by HG and 189 patients were managed by NHG after surgery. The length of hospital stay in the first group was shorter (9.6 ± 5.8 days vs. 12.2 ± 7.9 days, P < 0.001), the incidence of complications was lower (44.6% vs. 55.6%, P = 0.019), and the readmission rate was lower (3.0% vs. 6.9%, P = 0.046) in the HG than in the NHG. The difference in total hospital costs was not significant between the HG and the NHG (₩8,381,304 vs. ₩9,242,493, P = 0.559), but surgery-independent hospital costs were lower in the HG than in the NHG (₩3,020,873 vs.₩3,923,308, P = 0.001). @*Conclusion@#The surgical hospitalist system reduced the length of hospital stay, the incidence of postoperative complications, and the readmission rates of surgical patients. This led to the effect of a reduction in total hospital costs.

LASSO-Based Machine Learning Algorithm for Prediction of Lymph Node Metastasis in T1 Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The role of tumor-infiltrating lymphocytes (TILs) in predicting lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC) remains unclear. Furthermore, clinical utility of a machine learning–based approach has not been widely studied. @*Materials and Methods@#Immunohistochemistry for TILs against CD3, CD8, and forkhead box P3 in both center and invasive margin of the tumor were performed using surgically resected T1 CRC slides. Three hundred and sixteen patients were enrolled and categorized into training (n=221) and validation (n=95) sets via random sampling. Using clinicopathologic variables including TILs, the least absolute shrinkage and selection operator (LASSO) regression model was applied for variable selection and predictive signature building in the training set. The predictive accuracy of our model and the Japanese criteria were compared using area under the receiver operating characteristic (AUROC), net reclassification improvement (NRI)/integrated discrimination improvement (IDI), and decision curve analysis (DCA) in the validation set. @*Results@#LNM was detected in 29 (13.1%) and 12 (12.6%) patients in training and validation sets, respectively. Nine variables were selected and used to generate the LASSO model. Its performance was similar in training and validation sets (AUROC, 0.795 vs. 0.765; p=0.747). In the validation set, the LASSO model showed better outcomes in predicting LNM than Japanese criteria, as measured by AUROC (0.765 vs. 0.518, p=0.003) and NRI (0.447, p=0.039)/IDI (0.121, p=0.034). DCA showed positive net benefits in using our model. @*Conclusion@#Our LASSO model incorporating histopathologic parameters and TILs showed superior performance compared to conventional Japanese criteria in predicting LNM in patients with T1 CRC.

A surgical hospitalist system in Korea: a preliminary study of the effects on hospital costs and postoperative outcomes

Purpose@#The aim of this study is to investigate the effect of the surgical hospitalist system on postoperative outcomes and hospital costs for surgical patients. @*Methods@#We reviewed the medical records of 522 patients who were admitted to the divisions of colorectal and gastrointestinal surgery for operation from September to December 2017 at Severance Hospital, Yonsei University College of Medicine in Seoul, Korea. All patients were divided into 2 groups; one that was managed by surgical hospitalists group (HG) and another that was managed by non-hospitalist residents group (NHG) after elective surgery. Postoperative outcomes and hospital costs were analyzed for each group. @*Results@#Two hundred ninety-eight patients were managed by HG and 189 patients were managed by NHG after surgery. The length of hospital stay in the first group was shorter (9.6 ± 5.8 days vs. 12.2 ± 7.9 days, P < 0.001), the incidence of complications was lower (44.6% vs. 55.6%, P = 0.019), and the readmission rate was lower (3.0% vs. 6.9%, P = 0.046) in the HG than in the NHG. The difference in total hospital costs was not significant between the HG and the NHG (₩8,381,304 vs. ₩9,242,493, P = 0.559), but surgery-independent hospital costs were lower in the HG than in the NHG (₩3,020,873 vs.₩3,923,308, P = 0.001). @*Conclusion@#The surgical hospitalist system reduced the length of hospital stay, the incidence of postoperative complications, and the readmission rates of surgical patients. This led to the effect of a reduction in total hospital costs.

Step-wise learning of laparoscopic low anterior resection

A primary goal of training is the development of one’s own procedure by self-learning, which can be facilitated by laparoscopic surgery owing to its recordable system. This video demonstrates laparoscopic low anterior resection for a 56-year-old male diagnosed with synchronous S-colon cancer and rectal cancer.The surgery was performed by a second-year fellow in the colorectal division under supervision.

Screening for Lung Cancer Using Low-dose Chest Computed Tomography in Korean Long-term Colorectal Cancer Survivors

BACKGROUND: The National Lung Screening Trial (NLST) and NELSON trial showed that low-dose chest computed tomography (LDCT) screening significantly reduced the mortality form lung cancer. Although cancer survivors are known to have high risk for second malignant neoplasm (SMN), the usefulness of LDCT screening for lung cancer in cancer survivors is not clear. METHODS: Between August 2016 and August 2017, 633 long-term colorectal cancer (CRC) survivors visited the survivorship clinic in Cancer Prevention Center, Yonsei Cancer Center, Seoul, Republic of Korea. We surveyed the smoking status and recommended LDCT screening to ever-smoking CRC survivors aged 55–80 years. The participants were classified into three risk groups: risk group 1 (RG1) who met the NLST criteria (Age 55–74 years, ≥ 30 pack-years of smoking, smoking cessation < 15 years); risk group 2 (RG2) who would not meet the NLST criteria but were at increased 6-year risk of lung cancer (PLCOM2012 ≥ 0.0151); risk group 3 (RG3) who did not meet any of the criteria above. RESULTS: Among 176 ever-smoking CRC survivors, 173 (98.3%) were male, 32 (18.2%) were current-smoker, and median age was 66 years (range, 55–79 years). We found 38 positive findings (non-calcified nodule ≥ 4 mm), 8 clinically significant findings, 66 minor abnormalities, and 64 negative findings on LDCT. Positive findings were identified in 15 of 79 (19.0%) of RG1, in 9 of 36 (25%) of RG2, and in 14 of 61 (23.0%) of RG3. Second primary lung cancers were found in 2 patients of RG2, and in 1 patient of RG3. SMN was most frequently found in RG2 (11 of 36 patients, 30.6%), compared with RG1 (12.7%) or RG3 (9.8%) (P = 0.016). CONCLUSIONS: LDCT screening for lung cancer in Korean CRC survivors is feasible. Well-designed clinical trial for defining high risk patients for lung cancer among CRC survivors is needed.

Single-center Experience of 24 Cases of Tailgut Cyst

PURPOSE: Tailgut cysts are rare congenital or developmental lesions that arise from vestiges of the embryological hindgut. They are usually present in the presacral space. We report our single-center experience with managing tailgut cysts. METHODS: We conducted a retrospective analysis of 24 patients with tailgut cyst treated surgically at the Colorectal Surgery Department of Severance Hospital, Yonsei University, Seoul, South Korea, between 2007–2018. RESULTS: This study included 24 patients (18 females) with a median age of 51.5 years (range, 21–68 years). Ten cases were symptomatic and 14 were asymptomatic. Cysts were retrorectal in 21 patients. Cysts were below the coccyx level in 16 patients, opposite the coccyx in 6, and above the coccyx in 2. Cysts were supralevator in 5 patients, had a supra- and infralevator extension in 18 patients, and were infralevator in 1. Ten patients were managed using an anterior laparoscopic approach, 11 using a posterior approach, and 3 using a combined approach. Mean cyst size was 5.5 ± 2.7 cm. Postoperative complications were Clavien-Dindo (CD) classification grade II in 9 patients (37.5%) and CD grade III in 1 (4.2%). The posterior approach group showed the highest rate of complications (P = 0.021). Patients managed using a combined approach showed a larger cyst size (P < 0.001), longer operation times (P < 0.001), and a greater likelihood of tumor level above the coccyx (P = 0.002) compared to other approaches. The tumors of 2 male patients were malignant: 1 was a neuroendocrine tumor treated with radiotherapy, while the other was a closely followed adenocarcinoma. Median follow-up was 12 months (range, 1–66 months) with no recurrence. CONCLUSION: Tailgut cysts are uncommon but can cause perineal or pelvic pain. Complete surgical excision via an appropriate approach according to tumor size, location, and correlation with adjacent pelvic floor muscles is the key treatment.

Short-term Outcomes After Upfront Chemotherapy Followed by Curative Surgery in Metastatic Colon Cancer: A Comparison With Upfront Surgery Patients

PURPOSE: Upfront systemic chemotherapy with target agents has been recommended for patients with stage IV colon cancer. Some with partial response are considered for curative resection. There is high risk of developing postoperative complications following upfront systemic chemotherapy. We aimed to evaluate short-term perioperative outcomes of curative surgery after upfront chemotherapy in comparison with upfront surgery in patients with metastatic colon cancer.METHODS: Between January 2010 and October 2015, 146 patients (80 in the surgery first group, 66 in the upfront chemotherapy group) who underwent surgical resection before or after systemic chemotherapy for metastatic colon cancer were included in the present study. All decisions for treatment were made through a multidisciplinary team. Postoperative clinical outcomes and complications were analyzed to compare the groups.RESULTS: There was no difference between the 2 groups in terms of postoperative clinical outcomes. Overall complication rates were not different between the groups (surgery first group: 46.3% vs. upfront chemotherapy group: 60.6%; P = 0.084). When classified according to the Clavien-Dindo method, there was no difference between the 2 groups in terms of major complications (grade 3 or more) (surgery first group: 18.9% vs. upfront chemotherapy group: 27.5%; P = 0.374).CONCLUSION: There was no significant increase in major postoperative complications in metastatic colon cancer patients who received upfront chemotherapy followed by curative surgery. Careful patient selection and treatment planning are important.

Impact of Adjuvant Chemotherapy Completion on Oncologic Outcomes in ypTNMstage 2 Rectal Cancer Patients

PURPOSE: Adjuvant chemotherapy (aCT) in rectal cancer patients who have undergone curative resection after neoadjuvant chemoradiation (nCRT) is controversial. We aimed to investigate the benefits of using aCT and the clinical impact of completing aCT in ypstage 2 rectal cancer patients.METHODS: We retrospectively reviewed clinicopathological data from patients who had undergone radical resection after nCRT between January 2006 and December 2012. In total, 152 patients with ypT3/4N0M0 rectal cancer were included. Of these patients, 139 initiated aCT, while 13 did not receive aCT (no-aCT). Among those who received aCT, 132 patients completed their planned cycles (aCT-completion) whereas 7 did not (aCT-incompletion). All patients received longcourse chemoradiation; a 5-fluorouracil-based regimen was used for nCRT in most patients. The prognostic factors affecting disease-free survival (DFS) and overall survival (OS) were analyzed.RESULTS: The median follow-up duration was 41 months. Demographic data did not differ significantly among the 3 groups. In multivariate analysis, open surgery, a tumor size >2 cm, retrieval of <12 lymph nodes, circumferential resection margin (CRM) positivity and aCT incompletion were independent prognostic factors for poor DFS. Old age (≥60 years), open surgery, CRM positivity, aCT incompletion, and lack of aCT initiation compared to aCT completion were independent prognostic factors for poor OS.CONCLUSION: In ypstage 2 rectal cancer patients, aCT after nCRT and total mesorectal excision affected both DFS and OS; however, only patients who completed planned aCT exhibited survival benefits. Therefore, improving patients’ compliance with the completion of aCT is desirable.

Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

PURPOSE: Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients. METHODS: We identified stage I–III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis. RESULTS: Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07–2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22–2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05–3.29; P = 0.031) in stage III patients. CONCLUSION: RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

CpG Island Methylator Phenotype and Methylation of Wnt Pathway Genes Together Predict Survival in Patients with Colorectal Cancer

PURPOSE: Dysregulation of the Wnt pathway is a crucial step in the tumorigenesis of colorectal cancer (CRC). This study aimed to determine whether DNA methylation of Wnt pathway genes helps predict treatment response and survival in patients with metastatic or recurrent CRC. MATERIALS AND METHODS: We retrospectively collected primary tumor tissues from 194 patients with metastatic or recurrent CRC. Pyrosequencing was used to examine the methylation of 10 CpG island loci in DNA extracted from formalin-fixed paraffin-embedded specimens. To elucidate the predictive role of DNA methylation markers, Kaplan-Meier survival estimation and Cox regression were performed for progression-free survival and overall survival (OS). RESULTS: The methylation frequencies of the 10 genes analyzed (p16, p14, MINT1, MINT2, MINT31, hMLH1, DKK3, WNT5A, AXIN2, and TFAP2E) were 47.9%, 10.8%, 21.1%, 16.0%, 20.6%, 0.5%, 53.1%, 32.0%, 2.6%, and 2.1%, respectively. We divided patients into three groups based on the number of methylated genes (group 1, no methylation n=38; group 2, 1–2 methylations n=92; group 3, 3 or more methylations n=64). Among patients treated with palliative chemotherapy (n=167), median OSs of groups 1, 2, and 3 were 39.1, 39.7, and 29.1 months, respectively (log rank p=0.013). After adjustment, number of methylations was identified as an independent poor prognostic factor (0–2 methylated vs. ≥3 methylated: hazard ratio, 1.72; 95% confidence interval, 1.16–2.56, p=0.007). CONCLUSION: This study suggests that methylation of Wnt pathway genes, in addition to known CpG island methylator phenotype markers, may help predict treatment outcome and survival in patients with CRC.

Which Patients with Isolated Para-aortic Lymph Node Metastasis Will Truly Benefit from Extended Lymph Node Dissection for Colon Cancer? / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The prognosis of patientswith colon cancer and para-aortic lymph node metastasis (PALNM) is poor. We analyzed the prognostic factors of extramesenteric lymphadenectomy for colon cancer patients with isolated PALNM. MATERIALS AND METHODS: We retrospectively reviewed 49 patients with PALNM who underwent curative resection between October 1988 and December 2009. RESULTS: In univariate analyses, the 5-year overall survival (OS) and disease-free survival (DFS) rates were higher in patients with ≤ 7 positive para-aortic lymph node (PALN) (36.5% and 27.5%) than in those with > 7 PALN (14.3% and 14.3%; p=0.010 and p=0.027, respectively), and preoperative carcinoembryonic antigen (CEA) level > 5 was also correlated with a lower 5-year OS and DFS rate of 21.5% and 11.7% compared with those with CEA ≤ 5 (46.3% and 41.4%; p=0.122 and 0.039, respectively). Multivariate analysis found that the number of positive PALN (hazard ratio [HR], 3.291; 95% confidence interval [CI], 1.309 to 8.275; p=0.011) was an independent prognostic factor for OS and the number of positive PALN (HR, 2.484; 95% CI, 0.993 to 6.211; p=0.052) and preoperative CEA level (HR, 1.953; 95% CI, 0.940 to 4.057; p=0.073) were marginally independent prognostic factors for DFS. According to our prognostic model, the 5-year OS and DFS rate increased to 59.3% and 53.3%, respectively, in patients with ≤ 7 positive PALN and CEA level ≤ 5. CONCLUSION: PALN dissection might be beneficial in carefully selected patients with a low CEA level and less extensive PALNM.

Protective effect of Korean red ginseng on oxaliplatin-mediated splenomegaly in colon cancer

PURPOSE: This study investigated how adding Korean red ginseng extract (KRG) to folinic acid, fluorouracil and oxaliplatin (FOLFOX) chemotherapy affected the rate of splenomegaly in colon cancer. METHODS: This retrospective study analyzed 42 patients who were randomly assigned to receive a FOLFOX regimen with or without KRG. Spleen volume change was assessed by computed tomography scans measured before surgery (presurgery volume) and 3 weeks after cessation of the 12th cycle of FOLFOX (postchemotherapy volume). RESULTS: All patients showed increased spleen volume. No difference was observed in median presurgery and postchemotherapy volume between the KRG and control groups. However, a ratio defined as postchemotherapy volume divided by presurgery volume was significantly lower in the KRG group than the control group (median, 1.38 [range, 1.0–2.8] in KRG group vs. median, 1.89 [range, 1.1–3.0] in control group, P = 0.028). When splenomegaly was defined as a >61% increase in spleen volume, the rate of splenomegaly was significantly lower in the KRG group than the control group (28.6% vs. 61.9%, P = 0.03). KRG consumption was inversely associated with developing splenomegaly in multivariate analysis. CONCLUSION: Adding KRG during FOLFOX chemotherapy for colon cancer might protect against oxaliplatin-induced splenomegaly. The protective effect of Korean red ginseng should be investigated with further research.

Carcinoembryonic antigen levels of tumor-draining venous blood as a prognostic marker in colon cancer

PURPOSE: Carcinoembryonic antigen (CEA) is a tumor marker for colorectal cancer (CRC) related to recurrence and prognosis. We examined the ability of the CEA level measured directly from a tumor drainage vein (dCEA) to predict the prognosis of CRC more accurately than those from a peripheral vein (pCEA).METHODS: Fifty-two patients who received curative resection for colon adenocarcinoma were enrolled. The patients were categorized into two groups according to normal pCEA ( < 5.9425 ng/mL, n=24) or elevated pCEA levels (≥5.9425 ng/mL, n=28). Blood was sampled at the time of surgery simultaneously from the tumor drainage vein and from the peripheral vein.RESULTS: The clinicopathologic variables showed no significant difference between the two groups. Patients with dCEA levels < 20.192 ng/mL showed better disease-free (P=0.009) and overall survival (P=0.033) curves than those with dCEA levels ≥20.192 ng/mL. Elevated dCEA levels were a significant prognostic factor for overall survival and disease-free survival in Cox proportional hazard model analysis (hazard ratio [HR]=399; 95% confidence interval [CI], 16.4–9,747; P < 0.001; HR=9.39, 95% CI, 1.29–68.006; P=0.026). In subgroup analysis, we compared the data of normal range of dCEA group and elevated dCEA group with normal pCEA; the overall survival rate of patients with normal dCEA was better and the disease-free survival rate was significantly better (P=0.003).CONCLUSION: CEA levels from a tumor drainage vein can be used as more accurate prognostic markers than levels from a peripheral vein in patients with colon cancer.

Single Center Experience With Hyperthermic Intraperitoneal Chemotherapy

PURPOSE: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been proposed for controlling peritoneal seeding metastasis in some kinds of cancers, including those of colorectal origin, but their safety and oncological benefits are subjects of debate. We present our early experience with those procedures. METHODS: Data were retrospectively collected from all patients with peritoneal carcinomatosis (PC) and pseudomyxoma peritonei (PMP) treated using CRS and HIPEC at Yonsei Cancer Center between July 2014 and July 2015. Short-term outcomes and risk factors for postoperative complications were analyzed. RESULTS: Twenty-three patients with PC (n = 18) and PMP (n = 5) underwent CRS and HIPEC. Median follow-up and age were 2 months and 54 years, respectively. The median peritoneal carcinomatosis index score was 15, and CC0-1 was achieved in 78.3% of all patients. The median operation time and bleeding loss were 590 minutes and 570 mL, respectively. Grade-IIIa/grade-IIIb complications occurred in 4.3% (n = 1)/26.1% (n = 6) of the patients within 30 days postoperatively, and no 30-day mortalities were reported. Factors related to postoperative complications with CRS and HIPEC were number of organ resection (P = 0.013), longer operation time (P < 0.001), and amount of blood loss (P = 0.003). All patients treated with cetuximab for recurred colorectal cancer had grade-III postoperative complication. CONCLUSION: Our initial experience with CRS and HIPEC presented about 30% grade-III postoperative complications. Therefore, expert surgeons need to perform those procedures with great caution in selected patients who might benefit from it.

Laparoscopic and Robotic Surgeries for Patients With Colorectal Cancer Who Have Had a Previous Abdominal Surgery

PURPOSE: The impact of previous abdominal surgery (PAS) on surgical outcomes from laparoscopic and robot surgeries is inconclusive. This study aimed to investigate the impact of PAS on perioperative outcomes from laparoscopic and robotic colorectal surgeries. METHODS: From March 2007 to February 2014, a total of 612 and 238 patients underwent laparoscopic and robotic surgeries, respectively. Patients were divided into 3 groups: those who did not have a PAS (NPAS), those who had a major PAS, and those who had a minor PAS. We further divided the patients so that our final groups for analysis were: patients with NPAS (n = 478), major PAS (n = 19), and minor PAS (n = 115) in the laparoscopy group, and patients with NPAS (n = 202) and minor PAS (n = 36) in the robotic surgery group. RESULTS: In the laparoscopy group, no differences in the conversion rates between the 3 groups were noted (NPAS = 1.0% vs. major PAS = 0% vs. minor PAS = 1.7%, P = 0.701). In the robotic surgery group, the conversion rate did not differ between the NPAS group and the minor PAS group (1.0% vs. 2.8%, P = 0.390). Among the groups, neither the operation time, blood loss, days to soft diet, length of hospital stay, nor complication rate were affected by PAS. CONCLUSION: PAS did not jeopardize the perioperative outcomes for either laparoscopic or robotic colorectal surgeries. Therefore, PAS should not be regarded as an absolute contraindication for minimally invasive colorectal surgeries.

Oncologic outcomes of squamous cell carcinoma of the anal canal after chemoradiation therapy

PURPOSE: The aim of this study is to analyze the oncological outcomes of squamous cell carcinoma (SCC) of the anal canal after chemoradiation therapy (CRT) in a single institution.METHODS: Fifty-one patients with anal SCC who had been treated with CRT between January 2000 and December 2010 were analyze data single center in Korea.RESULTS: Forty-eight patients exhibited clinical complete response. After a median follow-up of 42.1 months, 13 patients (25.5%) showed recurrence. The disease-free survival (DFS) rate was 63.4% at 5 and 10 years. The overall survival (OS) rates were 83.6% (5 years) and 75.2% (10 years). Stage I: DFS, 100%; OS, 100%; stage II: DFS, 85.7%; OS, 100%; stage IIIA: DFS, 68.6%; OS, 87.5%; stage IIIB: DFS, 34.7%; OS, 48.4%; and stage IV: DFS and OS, 0%. The local recurrence patterns were as follows: pelvic node (n=4, 7.8%), inguinal node (n=1, 2.0%), and inguinal and pelvic node (n=1, 2.0%). The systemic recurrence patterns were as follows: lung (n=2, 3.9%), para-aortic node (n=1, 2.0%), and extrapelvic site (n=2, 3.9%). N-stage represented a single independent prognostic factor for recurrence (P<0.05).CONCLUSION: CRT for SCC of the anal canal is effective for oncological outcomes and sphincter preservation. The initial nodal status may affect the oncological outcome.