Septic shock and hepatic hemorrhage in NTRK-fusion retroperitoneal sarcoma: a case report on oncologic emergencies

Retroperitoneal sarcomas are rare, deep-seated tumors that frequently present late with nonspecific symptoms. In patients with neurotrophic tyrosine receptor kinase (NTRK)-fusion sarcomas, targeted therapies such as anlotinib may offer disease control but can also precipitate life-threatening complications, including septic shock and hemorrhage. This case is unique in its demonstration of a rapid transition from stable disease to an oncologic emergency, highlighting the challenges of balancing therapeutic benefit with toxicity.

A 71-year-old man with a 7-month history of retroperitoneal spindle cell sarcoma-confirmed by histopathology and fluorescence in situ hybridization (FISH) for an NTRK gene fusion-presented after transfer from an outside hospital with acute abdominal pain, progressive distension, and hemodynamic instability. His previous treatment included six cycles of targeted therapy with anlotinib and multiple courses of chemotherapy, which were complicated by myelosuppression and chronic hemorrhage requiring peritoneal drainage. Initial imaging at the referring institution revealed complex retroperitoneal pathology, subtle hepatic abnormalities, and evidence of bone destruction. Shortly after admission at our facility, despite an initial bedside ultrasound, the patient's condition deteriorated and emergent computed tomography (CT) confirmed a ruptured hepatic hemangioma with intra-abdominal and pelvic hemorrhage along with a heterogeneous, necrotic retroperitoneal mass invading adjacent structures. Urgent transarterial embolization, drainage procedures, and intensive supportive care stabilized his condition.

This case underscores the need for rapid, multidisciplinary intervention-including early contrast-enhanced imaging and interventional radiology-to manage oncologic emergencies in advanced NTRK-fusion sarcoma patients.