Sung Uhn Baek

Intestinal Perforation in Colorectal Cancers Treated with Bevacizumab (Avastin

Bevacizumab is a monoclonal antibody that targets vascular endothelial growth factor (VEGF), and it has shown promise as a clinical agent against metastatic colorectal cancer, and particularly in combination with chemotherapy. Bowel perforation is a known risk thats associated with bevacizumab use, but the etiology is unknown. Here we report on two cases of metastatic colorectal cancer in which the patients suffered from intestinal perforation after chemotherapy with bevacizumab. For the first case, a 47 year-old man had rectal cancer with concurrent liver and lung metastasis. He underwent chemotherapy with 5-fluorouracil, irinotecan and bevacizumab. Fever and abdominal pain developed seven days later, and rectal perforation was identified upon exploration 13 days later. For the second case, a 48 year-old woman had sigmoid colon cancer with peritoneal and ovary metastases. After seven days of chemotherapy with 5-fluorouracil, oxaliplatin and bevacizumab, exploratory surgery revealed a perforation at the ileum.

Clinical Characteristics of Multiple Primary Colorectal Cancers

PURPOSE Although multiple primary colorectal cancer has been recognized as a significant clinical entity, its clinical and pathological features and its prognosis are still controversial. The purpose of this study was to clarify clinical and pathological features of multiple primary colorectal cancer. MATERIALS AND METHODS Among 1669 patients who underwent surgery for primary colorectal cancer from January 1997 to June 2005, 26 patients (1.6%) with multiple primary colorectal cancer were identified. We reviewed clinical characteristics including diagnostic interval, lesions, operating methods, and TNM stage, and we defined the index lesion as the most advanced lesion among the synchronous lesions. For the purposes of the study, the colon and rectum were classified into three segments. The right-side colon included the appendix, cecum, ascending colon, hepatic flexure, and transverse colon, and the left-side colon included the splenic flexure, descending colon, and sigmoid colon. RESULTS Of the 26 patients with multiple primary colorectal cancers, nineteen patients were male and seven patients were female, with a mean age of 61.5 years. Nineteen patients had synchronous colorectal cancers and seven patients had metachronous colorectal cancers. In the metachronous cases, the mean diagnostic interval was 36.8 months. The site of the first lesion in metachronous colorectal cancers was the right colon in five cases (71.4%) and the left colon in two cases (28.6%), and the site of the second lesion was the rectum in six cases (55.5%), the right colon in three cases (33.3%), and the left colon in one case. The TNM stage of the second lesions in the metachronous colorectal cancers was stage II in four cases (57.1%), stage III in one case (14.3%), and stage IV in one case (14.3%). For the synchronous colorectal cancers, the operation methods were single-segment resection combined with endoscopic mucosal resection in five cases (26.3%), single-segment resection alone in six cases, two-segment resection in six cases, and total colectomy in two cases. CONCLUSION In metachronous colorectal cancers, the secondary lesions were later-stage cancer. Therefore, careful postoperative follow-up is necessary for patients who have undergone surgery for colorectal cancers. Further study of therapeutic modalities is important for synchronous colorectal cancers.

Adenocarcinoma in Ileal Pouch after Proctocolectomy for Familial Adenomatous Polyposis: Report of A Case

Restorative proctocolectomy with ileal pouch-anal anastomosis is one of the surgical treatments of choice for patients with familial adenomatous polyposis. Although the risk of cancer developing in an ileal pouch is not yet clear, a few cases of adenocarcinoma arising in an ileal pouch have been reported. We report a case of adenocarcinoma in ileal pouch after proctocolectomy with ileal pouch-anal anastomosis. A 56-yr-old woman was diagnosed as having familial adenomatous polyposis. Total colectomy with ileorectal anastomosis was performed. Six years later, she underwent completion-proctectomy with ileal J pouch-anal anastomosis including anorectal mucosectomy for rectal cancer. After 7 yr, she presented with anal spotting. Endoscopic biopsies revealed adenocarcinoma at the ileal pouch. Resection of the ileal pouch and permanent ileostomy were performed. The risk of cancer in an ileal pouch and its prevention with regular surveillance must be emphasized.

Clinical significance of carcinoembryonic antigen in peritoneal fluid detected during operation in stage I–III colorectal cancer patients

Background/Aims Early diagnosis of peritoneal metastases in patients with colorectal cancer (CRC) can influence patient prognosis. The aim of this study was to identify the clinical significance of carcinoembryonic antigen (CEA) in peritoneal fluid detected during operation in stage I–III CRC patients. Methods Between April 2009 and April 2015, we reviewed medical records from a total of 60 stage I–III CRC patients who had peritoneal fluid collected during operation. Patients who had positive cytology in the assessment of peritoneal fluid were excluded. We evaluated the values of CEA in peritoneal fluid (pCEA) to predict the long-term outcomes of these patients using Kaplan-Meier curves and Cox regression models. Results The median follow-up duration was 37 months (interquartile range, 21–50 months). On receiver operating characteristic analysis, pCEA had the largest area under the curve (0.793; 95% confidence interval, 0.635–0.950; P=0.001) with an optimal cutoff value of 26.84 (sensitivity, 80.0%; specificity, 76.6%) for predicting recurrence. The recurrence rate was 8.1% in patients with low pCEA (<26.84 ng/mL, n=37), and 52.2% in patients with high pCEA (≥26.84 ng/mL, n=23). In multivariate Cox regression analysis, high pCEA (≥26.84 ng/mL) was a risk factor for poor cancer-free survival (CFS) in stage I–III patients. Conclusions In this study, we determined that high pCEA (≥26.84 ng/mL) detected during operation was helpful for the prediction of poor CFS in patients with stage I–III CRC.