Natural history of gastric leiomyoma

Most gastric leiomyomas are asymptomatic and benign subepithelial tumors (SETs); however, some may increase in size or become symptomatic. Understanding their natural history is therefore important to their management. We investigated the natural history of histologically proven gastric leiomyomas.

We retrospectively reviewed histologically proven gastric leiomyoma cases at a tertiary center. The baseline characteristics of these cases were analyzed, and those with a follow-up period of at least 12 months without immediate resection were evaluated. The primary outcome was the frequency of size increase of more than 25% during the follow-up period, and the secondary outcome was the histopathologic results in cases that underwent resection.

Among the 231 patients with histologically proven gastric leiomyomas, the most frequent location was the cardia (77.1%), and the median size was 3 cm (IQR 2-4 cm). Eighty-four cases were followed up over a median period of 50.8 months (IQR 27.2-91.3 months). During the follow-up period, tumor size increased in two cases (2.4%). Surgical results showed that one case was leiomyoma, and the other was leiomyosarcoma. Among the remaining cases without change in size, 15 underwent surgical resection (n = 10) or endoscopic resection (n = 5), and all cases were confirmed as leiomyoma.

Most gastric leiomyomas are benign SETs, and an increase in size is not frequent, even in large-sized cases. Close monitoring with routine follow-up without resection may be sufficient in cases of histologically proven gastric leiomyoma. However, in cases of ulceration or size increase, resection may be beneficial.