Gastric gastrointestinal stromal tumors. Is there a necessity to use imatinib in the intermediate-risk group?

Background: A gastrointestinal stromal tumor (GIST) is a tumor that occurs in the gastrointestinal tract, most frequently in the stomach or small intestine. This study aimed to reveal the clinical, histopathological, and immunohistochemical features of patients with GIST and to determine the effect of adjuvant tyrosine kinase inhibitor (TKI) use on survival rates in intermediate-risk gastric GIST cases.

Methods: Clinical characteristics, histopathological findings, and oncological outcomes of 51 patients operated on for gastric GIST between 2010 and 2019 were analyzed retrospectively. Patients treated with neoadjuvant and adjuvant TKI were identified. The effect of adjuvant therapy on survival in the intermediate-risk group was examined.

Results: There were 33 females and 18 males, with a mean age of 64.9 ± 12.8 years. The most common surgical procedure was gastric wedge resection. Three cases were treated with laparoscopy, and 48 underwent open surgery. A multi-visceral resection was carried out in three cases. All cases underwent R0 resection. In the intermediate-risk group, there were no statistical differences between individuals receiving adjuvant therapy (n =12) and those not receiving adjuvant therapy (n =6) regarding survival rates (p =0.157). The average follow-up period was 54.9 (min: 2 - max: 106) months. Over this period, in three and five patients, recurrence and metastases occurred, respectively, and seven patients succumbed to the disease. Disease-free survival for five years was 93.7 %, metastasis-free survival was 83.4 %, and overall survival was 86.7 %. HIPPOKRATIA 2021, 25 (3):113-118.

Conclusions: This study showed that adjuvant TKI therapy did not affect survival rates in intermediate-risk gastric GIST.