Primary Ewing's Sarcoma of the Sternum in an Adult Male: A Rare Case Report.

Ewing's sarcoma, a rare primary bone malignancy primarily affecting adolescents and young adults, typically manifests in the pelvic bones and femur. Primary Ewing's sarcoma of the sternum is exceptionally rare, constituting less than 1% of cases. We present a case of a 34-year-old man with a 2-month history of anterior chest wall pain initially attributed to muscular spasm. Subsequently, the patient developed a palpable mass and imaging demonstrated a mid-lower sternal lesion with cortical destruction and soft tissue involvement, confirmed as Ewing's sarcoma on biopsy. In addition, a suspicious lesion was identified in the left distal tibia, which was histologically confirmed as a metastasis from the primary sternal sarcoma. Neoadjuvant chemotherapy preceded partial sternotomy with rib resection and reconstruction, achieving clear surgical margins. Postoperative evaluation showed shrinkage in the sternal lesion and near-resolution of the tibial metastasis. Subsequent chemotherapy cycles resulted in no evidence of the disease on the follow-up positron emission tomography scan. This case underscores the diagnostic challenges of primary sternal Ewing's sarcoma and emphasizes the importance of early recognition and comprehensive evaluation in managing such rare presentations.