Aggressive Primary Adrenal Leiomyosarcoma with Pancreatic and Gastric Involvement: Lessons from a Rare Case

Background: Primary adrenal leiomyosarcoma (PAL) is an exceedingly rare malignant neoplasm arising from smooth muscle elements of the adrenal gland or its associated vasculature. Fewer than 60 cases have been reported in the literature, and presentation with contiguous multivisceral invasion is exceptionally uncommon, posing significant diagnostic and surgical challenges.Case Presentation: A 74-year-old male presented with left flank pain. Cross-sectional imaging revealed a large left adrenal mass measuring 13 × 13 cm with obliteration of surrounding fat planes and direct invasion into adjacent organs, including the pancreas, spleen, gastric muscularis, and left diaphragmatic crus. The mass caused compression of the splenic vessels with associated splenic vein thrombosis. Given the locally advanced nature of the disease, the patient underwent multivisceral “en-bloc” resection comprising left adrenalectomy, distal pancreatectomy, splenectomy, and distal gastrectomy. Histopathological examination confirmed primary adrenal leiomyosarcoma with infiltration into the pancreatic parenchyma and gastric muscularis propria. All surgical margins were free of tumour.Discussion: PAL with direct multiorgan involvement is extremely rare, and preoperative diagnosis is often difficult due to nonspecific clinical and radiological features. Complete surgical excision with negative margins remains the cornerstone of treatment and offers the best chance for durable local control in the absence of distant metastasis.Conclusion: This case highlights an exceptionally rare presentation of primary adrenal leiomyosarcoma with extensive contiguous organ invasion. Radical “en-bloc” resection, when technically feasible, can achieve clear margins and may offer curative potential. Reporting such cases contributes to the limited existing literature and helps guide surgical decision-making in this rare malignancy.