Natural history and treatment outcomes in aggressive angiomyxoma: A single institution experience

Aggressive angiomyxoma (AA) is a rare, locally infiltrative mesenchymal tumor with frequent local recurrence. Optimal management remains poorly defined, particularly the roles of surgery, endocrine therapy, and observation.

We retrospectively analyzed patients with histologically confirmed AA treated at a single institution from 2000 to 2024. Clinical, pathologic, and treatment data were collected. Overall survival (OS), relapse-free survival (RFS), duration of treatment (DOT), and radiographic response by quasi-RECIST 1.1 were assessed descriptively.

Forty patients were included; median age was 42 years, 87.5% were female, and median tumor size was 9.9 cm. Initial management was surgery in 30 patients, systemic therapy in 8, and observation in 2. Among patients initially managed with surgery, median OS from the time of first resection was not reached at a median follow-up of 68.6 months; estimated 10-year OS was 95% (95% CI, 68%-99%). Among patients with R0/R1 resection, median RFS was 49.8 months (95% CI, 21.0-64.7), with 3-year RFS of 56% (95% CI, 31%-75%). Tumor size and margin status were not significantly associated with recurrence. Thirteen patients received systemic therapy, predominantly endocrine-based; ORR was 25% and median DOT was 15.4 months. Two patients were initially observed, and three with residual macroscopic disease after R2 resection remained free from further intervention for prolonged periods. Radiation therapy was rarely used.

AA was associated with excellent long-term survival despite frequent recurrence or subsequent intervention after surgery. Endocrine therapy showed objective activity in a subset of patients. Observation or delayed intervention may be feasible in selected, clinically stable patients with untreated or residual macroscopic disease, supporting individualized, function-preserving management focused on symptoms, morbidity, and patient preferences.