Background: Removal of the primary lesion with a clear operative margin is the standard treatment for gastrointestinal stromal tumor (GIST) of the stomach. However, there are few reports on the operative indications for relatively small GIST.
Methods: Clinicopathologic features and survival data of all 60 patients with GIST of the stomach treated at Keio University Hospital from 1993 to 2004 were analyzed. Laparoscopic wedge resection was used as the primary procedure for tumors between 2 to 5 cm. Tumors larger than 5 cm were resected by laparotomy or laparoscopy-assisted operation.
Results: Thirty-five lesions (58.3%) were resected by laparoscopic wedge resection, 3 by laparoscopic operation with a small skin incision and 22 by conventional open procedures. The mean size of the tumors was 42.5 mm, with a range of 18 to 150 mm and a median value of 35.5 mm. All operative margins were clear, but 1 patient had liver metastases at the time of resection of the primary lesion. The median follow-up period was 53 months and the 5-year disease-free survival rate (DFS) was 96.1%. No local recurrence or distant metastasis was encountered in patients with tumors smaller than 4 cm. A statistically significant correlation was observed between tumor size and mitotic count in this cohort (P = .010). Tumors from the intermediate- (n = 14) and high-risk (n = 10) groups as classified by the Risk Assessment Classification showed significantly worse DFS than the low-risk and very low risk group (n = 35) (89.9% vs 100% in 5-year DFS, P = .045). Even among tumors smaller than 3 cm, 2 of 14 cases (14.3%) were classified into the intermediate-risk group.
Conclusions: Although a prospective randomized trial remains to be performed, this study provides additional evidence suggesting that the early removal of GIST, at 5 cm or less in size, provides better DFS than later removal of the tumor at a larger size.