Chest wall malignancies are rare, constituting only 1% of all cancers. Prostate cancer, the second most common in men, typically metastasizes to bones, lymph nodes, and organs. However, sternum involvement is exceptionally rare, particularly with osteolytic metastasis. We report a 75-year-old man, clinically presenting with large anterior chest wall mass, which on further investigation revealed an expansile osteolytic sternal body metastasis from prostate cancer. This rarity poses diagnostic and therapeutic challenges, as documented cases of osteolytic secondaries to the sternum are scarce in medical literature. Diagnostic efforts involved comprehensive imaging and biopsy, confirming prostate cancer metastasis. Management requires a multidisciplinary approach, balancing effective cancer control with preserving the patient"s quality of life through systemic therapies, radiation, and surgery. The scarcity of osteolytic sternal body metastasis in reported cases highlights the atypical pattern of metastasis in prostate cancer emphasizing the need for a deeper understanding and contributing to the knowledge of this uncommon manifestation.

Keywords : prostate cancer, sternal metastasis, osteolytic presentation, chest wall tumors, positron emission tomography, multidisciplinary approach