A successful complete resection for multidrug-resistant giant gastrointestinal stromal tumor invading the transverse colon with multiple liver metastases in a young female: a case report.

Background: Gastrointestinal stromal tumors (GISTs) are rare in young people and are often detected after becoming symptomatic or at an advanced stage. Herein, we report a case of complete reduction surgery for a substantially large malignant gastric GIST with multiple liver metastases in a young woman who successfully resulted in R0 surgery.

Case presentation: An 18-year-old woman presented to our hospital with anorexia and vomiting, and was diagnosed with a 17 cm gastric GIST with transverse colon invasion and multiple liver metastases. Due to being considered unresectable, tyrosine and multi-kinase inhibitor therapy were administered up to the fourth line yielding no response. After careful discussion at a multidisciplinary team conference, pancreatoduodenectomy or distal gastrectomy, transverse colectomy, and resection of the liver metastases were planned. Consequently, distal gastrectomy, transverse colectomy, resection of the liver metastases, and incidental peritoneal metastases were performed. Although the primary goal of the surgery was to reduce the volume of the tumor as much as possible, the results revealed that the complete removal of all detectable tumors was achieved. No recurrence was observed after surgery for 27 months with long-term adjuvant imatinib therapy.

Conclusions: Even for highly advanced GISTs, aggressive surgery followed by adjuvant drug therapy may prolong survival in young patients.