Background: Gastrointestinal stromal tumors (GISTs) are originated from gastrointestinal (GI) tract or extra-GI tract (EGIST), mostly driven by c-KIT mutation that promise response to Imatinib. Despite good response to systemic treatment in the targeted therapy era, tumor lysis syndrome of solid malignancy is still rare.
Methods: A report of a case in our institution with collection of clinical data, management and literature review.
Results: We reported a 50 year old female patient presented with hemorrhagic ascites, abnormal uterine bleeding, multiple large intraabdominal and both adnexal masses. Initial treatment with chemotherapy base on ascites cytology suggestive of metastatic carcinoma showed poor response outcome so cytoreductive surgery was done. The pathological findings were epithelioid morphology cells, mitotic count 20-30/10 hpf, immunohistochemistry positive reactivity for CD117 and DOG1 so final diagnosis was metastatic EGIST. After 2 weeks of Imatinib 400 mg/d patient developed acute kidney injury, high serum uric 20.2 mg/dL and numerous urine uric acid crystal. A review of history was without other potentially nephrotoxic and hyperuricemia agents so diagnosis with the tumor lysis syndrome (TLS) was established. After stop Imatinib, aggressive hydration and gently titration Allopurinol patient serum uric was gradually decreased and renal function was improved and was re-challenge treatment with Imatinib 200 mg/day. Initial follow up were clinically and laboratory stable but after 1-month patient re-admitted with sepsis and peritonitis without neutropenia, clinical were rapidly deterioration and her family decided to against any further management. Conclusions: EGIST are rare, but more aggressive and poorer prognosis. Our report showed that TLS associated with targeted therapy was possible in some situation included large tumor burden that has a good response to therapy with predisposing patient factors. Several GIST with TLS report consistent with our outcome, some of the patients be able to survive after good supportive treatments and re-challenge treatment can be possible but long-term mortality is still high. We suggest that an awareness and early detection is the major role of management.