Positive Circumferential Resection Margin in Rectal Cancer Is a Robust Predictor of Poor Long-term Prognosis With Clinicopathological Bias Between Groups Compensated by Propensity-score Matching Analysis.

BACKGROUND/AIM: Circumferential resection margin (CRM) is the most reliable predictor of local and distant recurrence in locally-advanced rectal cancer (LARC). The present study was conducted to compare the long-term outcomes between CRM (+) and (-) groups using propensity-score (PS) matching analysis to compensate for bias between groups. PATIENTS AND METHODS: Of 563 consecutive patients with Stage II/III rectal cancer who were treated surgically with curative-intent at Juntendo University Hospital between Jan 1989 and Mar 2018, 412 patients were enrolled retrospectively in the study. The patients were divided into a CRM (+) group (n=21; 5.1%) and a CRM (-) group (n=391; 94.9%). RESULTS: In the entire cohort, recurrence-free survival (RFS), local recurrence-free survival (LRFS), non-local recurrence-free survival (NLRFS), and cancer-specific survival (CSS) were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. Univariate analysis demonstrated patients in the CRM (+) group had significantly larger primary tumors (p=0.02), more frequently had open surgery (p=0.009), had an abdominoperineal resection (APR) procedure (p=0.01) and a T4 primary tumor (p<0.0001). After PS matching analysis, in the propensity-matched cohort, RFS, LRFS, NLRFS and CSS were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. CONCLUSION: PS matching analysis demonstrated that RFS, LRFS, NLRFS, and CSS were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. The present results indicate that CRM (+) is a robust predictor of long-term outcome of LARC, independent of tumor size.

[A Case of Cecum Cancer with Lymph Node Metastasis and Invasion in the Superior Mesenteric Vein Treated with Combined SMV Resection and Reconstruction].

The patient was a 77-year-old woman. She visited her family doctor with a complaint of bloody stools, and was pointed out a Type 3 colon cancer in the cecum with a colonoscopy. In addition, an enlarged lymph node(#203)was found on the right side of the superior mesenteric vein(SMV). Laparoscopic surgery was initiated, and when the patient was moved to vascular processing, a firm adhesion of the lymph node(#203)was observed on the right side of the SMV. A small laparotomy was added, and a partial combined resection of the SMV was performed en bloc to complete the ileal resection. Histopathological findings showed T4b(transverse colon)N3M0, pStage Ⅲc, and metastatic lymph node(#203)showed evidence of invasion to the SMV. Adjuvant chemotherapy was administered, but lung metastases appeared 4 months and liver metastasis appeared 29 months after surgery. The patient was transferred to a different hospital for best supportive care(BSC)at 34 months after surgery.

Local recurrence of submucosal invasive colorectal cancer after endoscopic submucosal dissection revealed by copy number variation.

We report a case in which analysis of copy number variation revealed local recurrence of submucosal invasive colorectal cancer after curative endoscopic submucosal dissection (ESD). An 86-year-old man with a history of abdominoperineal resection of the rectum for rectal cancer underwent resection with ESD for early-stage sigmoid cancer 5 cm away from the stoma opening. At the same time, ileocecal resection was performed for advanced cecal cancer. Twelve months after ESD, advanced cancer occurred in the area of the ESD lesion. It was unclear if the cancer was a local recurrence after ESD, implantation of cecal cancer, or a new lesion. Copy number variation analysis performed for the three lesions revealed that the new lesion originated from residual tumor cells from ESD and was unlikely to be cecal cancer.

[A Case Report for Peritoneal Recurrences by Laparoscopic Surgery after Colorectal Cancer Resection].

We report a cases report of colorectal cancer who underwent repeated resection for peritoneal recurrences by laparoscopic surgery. In 2013, a 70-year-old woman diagnosed with an ascending colon cancer underwent laparoscopic right hemicolectomy. The pathological diagnosis was tub2, pT4aN1M0, Stage Ⅲb. Postoperative adjuvant chemotherapy(uracil and tegafur/Leucovorin)was administered. PET-CT performed at 25 months after the surgery because of CEA elevation. It revealed a peritoneal recurrence in the pouch of Douglas. The following peritoneal recurrences were removed by laparoscopic Hartmann's procedure. Chemotherapy(5-fluorouracil/levofolinate/oxaliplatin/bevacizumab)was administered 11 courses and after that chemotherapy(5-fluorouracil/levofolinate/bevacizumab)was administered 6 courses. PET-CT performed 37 months after the second surgery revealed a peritoneal recurrence near the right ovary in the pouch of Douglas. The following peritoneal recurrences was removed. Chemotherapy(tegafur/gimeracil/oteracil/bevacizumab)was administered 11 courses. The long-term survival has been continued for 7 years and 7 months after first operation. It was considered that laparoscopic surgery for peritoneal recurrence in colorectal cancer is contributed to one of the surgical procedures in selected patients.

[A Case Report of a Giant GIST Markedly Responsive to Neoadjuvant Chemotherapy with Imatinib Mesylate].

Male in his 50s complaining of abdominal pain was referred to our hospital. Abdominal CT scan showed a giant tumor which had diameter of approximately 50 mm in lower rectum. A biopsy specimen was positive for CD34 and c-kit. Based on these findings, it was diagnosed as gastrointestinal stromal tumor(GIST). We treated the patient with neoadjuvant therapy using imatinib mesylate(IM)to reduce the tumor size and to avoid the extensive surgery. The patient started to take IM at a daily dose of 400 mg. After 3 months, CT and MRI revealed that the tumor size decreased(40% reduction). We performed the robot assisted intersphincteric resection(ISR). Although it has been 28 months since the surgery, there are no obvious signs of recurrence. A patient diagnosed with giant GIST could avoid an extensive surgery due to neoadjuvant therapy with IM.