Motoki Yamamoto

Clinical impact of a macroscopically complete resection of colorectal cancer with peritoneal carcinomatosis

BACKGROUND So far, few reports have focused on the clinicopathological features and patterns of recurrence after a complete resection of peritoneal carcinomatosis (PC) of colorectal origin. The purpose of the present study was to show the clinicopathological features of a macroscopically complete resected tumor and the pattern of recurrence after the curative resection of colorectal PC. METHODS In 153 patients with colorectal PC, 31 patients who underwent a complete resection of a synchronous primary lesion of a colorectal PC between 1998 and 2007 were assessed retrospectively. RESULTS Clinicopathological differences were observed in the tumor location, presence of extraperitoneal metastases, extent of PC, and presence of lymph node metastases between a macroscopically complete resection and noncomplete resection patients (P = .045, P < .0001, P < .001, and P = .039, respectively). Tumor recurrence after the complete resection of colorectal PC was observed in 24 patients (77.4%). The 5-year survival rate after complete resection was 36.0%. The survival rate in the macroscopically complete resection group was higher than in the incomplete resection group (P < .001). The 5-year intra- and extraperitoneal recurrence survival rates were 63.9% and 33.8%, respectively. No significant clinicopathological factors affected intraperitoneal recurrence-free survival. Conversely, a univariate analysis using the log-rank test revealed that extended PC and presence of lymph node metastases were poor factors affecting extraperitoneal recurrence (P = .009 and P = .023, respectively). Eleven of 31 patients survived for 5 years after resection. Two of the 4 patients with liver metastases had received a hepatectomy. CONCLUSION Although the 5-year survival rate after a macroscopically complete resection for colorectal PC approached 36.0%, 77.4% of patients developed intra- and extraperitoneal recurrence. Extended PC and presence of lymph node metastases were poor factors affecting extraperitoneal recurrence.

Successful immunochemotherapy for patients with malignant mesothelioma: report of two cases.

Malignant mesothelioma is a clinically aggressive tumor and has a poor prognosis; therefore, the selection of therapeutic strategies is important to improve the prognosis. Two patients with intraperitoneal malignant mesothelioma received combination therapy as follows: (1) case-oriented chemotherapy according to the results of a chemosensitivity test, and (2) adoptive immunotherapy using cytotoxic T lymphocytes (CTL). The chemosensitivity test was assessed by an MTT colorimetric assay. CTL was generated by a mixed culture with autologous tumor cells, and activated by immobilized anti-CD3 monoclonal antibody and interleukin-2. The MTT assay indicated that cisplatin and adriamycin were sensitive drugs in both patients, and they thus received the caseoriented chemotherapy according to the MTT assay. The activated CTL exhibited a high cytotoxicity against autologous malignant mesothelioma cells, and were transferred intraperitoneally. The patients were controllable for ascites, and the tumor masses gradually vanished (partial response). Chemoimmunotherapy is thus considered to be an effective treatment for intraperitoneal malignant mesothelioma, especially to improve the quality of life.

Rectal obstruction by a giant pharmacobezoar composed of magnesium oxide: Report of a case

This report presents the rare case of a 75-year-old woman who developed a rectal obstruction caused by a pharmacobezoar, following the long-term ingestion of magnesium oxide cathartics for constipation. She was admitted to the hospital with lower abdominal pain and nausea. Abdominal computed tomography and magnetic resonance imaging showed that a huge calcified mass caused the rectal obstruction. A divided sigmoid colostomy was performed to relieve her symptoms, a colonoscopy from the distal stoma delineated a huge bezoar in the rectum, and thereafter she underwent an enterotomy. Magnesium oxide was detected in an analysis of a sample from this bezoar. Phamacobezoars resulting from laxatives or cathartics have rarely been reported. The current report showed a rectal obstruction caused by a pharmacobezoar composed primarily of magnesium oxide.