Synchronous multifocal osteosarcoma with atypical adrenal metastasis: a case report and literature review.

Introduction and importance: The most prevalent malignant bone tumor that typically impacts young adults is osteosarcoma. Synchronous multifocal osteosarcoma (SMOS) with metastasis is extremely rare, defined by the occurrence of various bone lesions being presented at the time of diagnosis. This report describes a rare case of SMOS with adrenal involvement and a simultaneous abdominal aortic aneurysm (AAA). Case presentation: We report a case of a 34-year-old Palestinian male with a history of hypertension and gout who presented with lower back and right leg pain. Imaging studies showed multiple lytic lesions in the lumbar spine, pelvis, and femur, confirming the presence of a metastatic disease. A whole-body CT scan revealed an adrenal mass and an AAA. A core needle biopsy confirmed the diagnosis of high-grade SMOS with metastasis. Clinical discussion: Osteosarcoma is the primary cancerous bone tumor that frequently impacts teenagers and young adults. Although multifocal osteosarcoma is rare, it is characterized by its aggressive nature and its possibility to metastasize. SMOS, which is a less common type, makes up only 0.6% of cases. Metastatic SMOS commonly impacts bones, including the pelvis, spine, and femur. While it is typical for cancer to spread to places like the lungs, the rare occurrence of metastasis to organs like the adrenal glands makes diagnosis and treatment more challenging. Conclusion: This case highlights the challenges in diagnosing and managing SMOS with unusual metastatic patterns and significant comorbidities. It emphasizes the importance of using interdisciplinary, comprehensive methods to optimize patient outcomes in such clinical scenarios.