Clinicopathologic features and prognosis of primary gastrointestinal stromal tumor patients under 35 years of age: A 10-year retrospective study.

Objectives: To investigate gastrointestinal stromal tumor (GIST) clinicopathologic characteristics in young adults.

Methods: Clinicopathologic data from GIST patients under 35 years diagnosed at our hospital from January 2005 to December 2014 were retrospectively collected.

Results: Thirty-one (5.3%, 31/585) patients were included; 17 (54.8%) were female. The most common presentation and primary tumor site were gastrointestinal bleeding (n = 18, 58.1%) and the small intestine (n = 13, 41.9%), respectively. Fifteen (48.4%) GISTs were classified as having a high relapse risk; two (6.4%), intermediate; nine (29.0%), low; and five (16.1%), very low. All patients underwent tumor resection. With a median follow-up of 51 months for 20 (64.5%) patients, 12 (60%) were given imatinib methylate as adjuvant therapy. One (5%) patient died of peritoneal GIST dissemination, four (20%) developed abdominal recurrences, two (10%) had hepatic metastasis, and thirteen (65%) were disease free. The 5-year disease-free survival rate was 51.2%.

Conclusions: GISTs rarely occur in young adults. The most common location is the small intestine. A slight female predominance was observed in the current study. Adjuvant therapy longer than the recommended duration may be beneficial for GISTs with a high relapse risk. Combined targeted therapy and surgery is appropriate for recurrent and metastatic GISTs in select patients. J. Surg. Oncol. 2016;114:977-981. © 2016 Wiley Periodicals, Inc.