Research Activities
Gastric:
The findings of Japan Clinical Oncology Group (JCOG) trial 9501, which obtained negative results, were published this year. No survival benefit from paraaortic lymph node dissection was found as against the standard D2 lymph node dissection (30).
In gastric surgery particularly in advanced cases where cancer is exposed on the serosal surface, cytological examination of the abdominal washing is a good method for detecting invisible peritoneal dissemination. Positive cytology would indicate short survival. We found that the 1-, 2-, and 3-year survival rates for 26 patients with positive cytology were 69, 35, and 0%, respectively (31).
In particular, it is very important to reduce complications after gastrectomy. Pancreatic fistula remains a fatal complication especially after pancreas-preserving total gastrectomy and pancreatosplenectomy. In this regard, various preservation methods of the splenic artery have been employed. Different types of treatments have also been performed for the stump of the pancreas, because the above-mentioned procedures are closely associated with the incidence of pancreatic fistula. As part of our research activities, we compared several procedures with special concern on the incidence of pancreatic fistula (32).
JCOG trials currently underway:
1.Assessment of combined modalities
1) JCOG trial 0501: A phase III trial to test the efficacy of neoadjuvant chemotherapy using TS-1+CDDP in patients with scirrhous gastric cancer and large size type III gastric cancer against a surgery preceding arm. Both arms are followed by adjuvant chemotherapy with S-1.
2.Assessment of surgical procedures
1) JCOG trial 0110: A phase III trial to confirm the efficacy of splenectomy in patients with advanced cancer in the upper part of the stomach,excluding cancer on the greater curvature line.
2) JCOG trial 0705: A phase III trial to confirm the efficacy and feasibility of palliative resection of the primary lesion in gastric cancer patients in whom laparoscopic examination has revealed incurable factors.
New Developments
Next to the ACTS-GC, JCOG aims to start a new RCT for adjuvant chemotherapy comparing S-1 and S-1+CDDP. A feasibility study of adjuvant S-1+CDDP in stage IIIB patients is now underway.
● M. Konishi ●
Research Activities in Hepatobiliary and Pancreatic Surgery
1) Intrahepatic cholangiocarcinoma
A retrospective analysis was undertaken to examine the clinicopathological features of intrahepatic cholangiocarcinoma, and to evaluate prognostic factors for predicting survival following surgical resection. The results indicate that intrahepatic metastasis was the strongest predictor of poor survival (33).
2) Pancreatic cancer
JASPAC-01: A randomized phase III trial has been started to compare orally administered S-1 with intravenous gemcitabine as adjuvant chemotherapy for patients with curatively resected pancreatic cancer. The hypothesis is that overall survival of pancreatic cancer patients after R0 or R1 resection is not significantly worse after adjuvant chemotherapy with S-1 than with gemcitabine (34).
3) Borderline malignancies and benign tumors of the pancreas
The recent development of various diagnostic techniques has led to the detection of an increasing number of borderline malignancies and benign tumors of the pancreas. The clinicopathological features of these lesions, such as solid pseudopapillary tumor, intraductal oncocytic papillary neoplasm and the focal type of autoimmune pancreatitis were examined. The results showed that a favorable outcome can be achieved by limited resection (35, 36, 37, 38).
● M. Konishi ●
Table of Contents