Yasuharu Mori

Detection and evaluation of epithelial cells in the blood of colon cancer patients using RT-PCR.

BackgroundAs a mode of colorectal cancer recurrence, liver metastasis plays an important role. One of the factors reported to predict liver metastasis is the detection of trace amounts of tumor cells in the blood. For this purpose, cancer cell-induced cytokeratins (CKs) are generally identified, using the reverse transcriptase-polymerase chain reaction (RT-PCR). In the present study, we aimed to detect trace amounts of tumor cells, based on CK20, in the circulating venous blood, and we examined pathological factors, liver metastasis, and prognosis.MethodsThe subjects were 57 colorectal cancer patients who had undergone operation. We examined the cancer-induced marker (CK20) in circulating venous blood by RT-PCR and investigated the relationships between this marker, pathological factors, and prognosis.ResultsDetection ratio of CK20 mRNA was 42.1%, and CK20 was significantly correlated with the pathological factor of lymph node metastasis(P = 0.037). The 5-year survival rate for CK20-positive patients was 62.5% and that for the CK20-negative patients was 87.5%; there was a significant difference(P = 0.048) between the two groups. Recurrence was recognized in six patients; two were positive for CK20 and four were negative for CK20.ConclusionsThese findings indicate that CK20 is strongly related to lymph node metastasis and prognosis, suggesting its usefulness for the diagnosis of colorectal cancer recurrence. However, CK20 did not predict liver metastasis.

Analysis of Autonomic Nerve Preservation and Pouch Reconstruction Influencing Fragmentation of Defecation after Sphincter-Preserving Surgery for Rectal Cancer

Our questionnaire survey on defecation disorders after rectal cancer surgery revealed that 66.7% of postoperative patients were most annoyed with fragmentation of defecation. Therefore, we performed a change-over-time analysis on the relationship of fragmentation and factors including location of rectal cancer, surgical technique, anastomosis method, pouch reconstruction, extent of lymph node dissection, and degree of pelvic and colonic nerve preservation surrounding the superior mesenteric artery. The fragmentation decreased over time at the postoperative time points of 6 months, 2 and 5 years. A statistical analysis of factors influencing fragmentation revealed that location of cancer, reconstruction technique, anastomosis method and degree of pelvic nerve preservation were significant factors for the entire patient population and that colonic nerve preservation was a significant factor 5 years after surgery. Analysis of patients with lower rectal cancer only showed that in addition to surgical technique and anastomosis method, pouch reconstruction was effective and autonomic nerve preservation was effective 5 years after surgery. As a result, when the anastomotic site was closer to the anus, the frequency of fragmentation increased; we concluded that pouch reconstruction was an effective surgical technique and colonic nerve preservation was effective in the longer term.

Carcinosarcoma of the Sigmoid Colon: Report of a Case.

Our case was a 65-year-old male, with the chief complaints of diarrhea and abdominal distention. Three years earlier, the patient had undergone transcatheter arterial embolization and radiofrequency treatment based on a diagnosis of hepatocellular carcinoma due to hepatitis B by another doctor. In October 2007, the patient developed diarrhea and increased abdominal distention. In December, CT examination conducted by the previous doctor revealed a 20-cm tumor within the pelvis. The patient was diagnosed with sigmoid colon cancer based on barium enema examination using gastrografin, and was introduced to our hospital for treatment. He was diagnosed with low-differentiated carcinoma by biopsy of the colon during endoscopy and underwent sigmoidectomy based on a diagnosis of sigmoid colon cancer. The tumor had infiltrated the bladder, and a tumorectomy was conducted through partially combined resection. The tumor was a huge lesion occupying the inside of the lumen, and histopathological findings revealed that the tumor, the main part of which lay beneath the mucous membrane, had a transitional image composed of both spindle-shaped atypical cells and sarcomatoid shape. The result of immunostaining was CK7(+), CK20(–), AFP(–), and the patient was diagnosed as having carcinosarcoma of the colon. Carcinosarcoma of the colon is a malignant tumor with poor prognosis, and the mean survival period in past reports was approximately 6 months. The patient was treated with FOLFIRI+Bevacizumab therapy according to chemotherapy for colon cancer, but he was refractory to the therapy.

Lymphoepithelioma-Like Carcinoma of the Colon

A 70-year-old female underwent follow-up colonoscopy after colonic polypectomy. The colonoscopy revealed the presence of a 7-mm submucosal tumor in the sigmoid colon. The tumor surface was smooth and covered with normal mucosa. It was diagnosed as a submucosal tumor, and polypectomy was performed. Histopathological examination of the resected specimen revealed moderately to poorly differentiated adenocarcinoma measuring 2 × 5 × 3 mm with marked peritumoral lymphocytic infiltration and lymphoid follicle formation. It was diagnosed as carcinoma with lymphoid stroma (lymphoepithelioma-like carcinoma), SM (1,800 μm), ly2, v0, budding; grade 1. We confirmed the indication for noncurative additional surgical resection and performed laparoscopic sigmoid colectomy. No metastases were observed in the dissected lymph nodes.

Oxaliplatin for Metastatic Colon Cancer in a Patient with Renal Failure

Objective Oxaliplatin, a key part of the standard regimen for colorectal cancer in Western countries, has become available in Japan. In a hemodialysis patient with cecal cancer, we investigated the efficacy, safety, pharmacokinetics, and dialysability of oxaliplatin. Methods A 65-year-old man who had cecal cancer was treated with oxaliplatin (40 mg/m2) and l-leucovorin(l-LV) (200 mg/m2), which were administered simultaneously over 120 min via the side and main arms of a Y-tube, respectively. Then 5-FU (400 mg/m2) was administered rapidly via the side tube, followed by 5-FU (2,000 mg/m2) over 46 hours via the main tube. The patient had chronic renal failure due to diabetic nephropathy and hemodialysis was performed 3 times a week. Blood samples were collected from the dialyzer before and after each hemodialysis session to examine platinum clearance. Results The patient received 3 courses of oxaliplatin before he died of cancer. During hemodialysis, the platinum level fell from 0.32 μg/mL to 0.15 μg/mL. Conclusion Since patients with renal failure have various associated disorders and oxaliplatin has a long half-life, it is necessary to obtain more pharmacokinetic data to investigate its accumulation and dialysability during long-term treatment. Such data will assist in treating the rapidly increasing number of hemodialysis patients with colorectal cancer.