{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T06:09:58Z","timestamp":1778738998891,"version":"3.51.4"},"reference-count":0,"publisher":"Indian Orthopaedic Research Group","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Jocr"],"published-print":{"date-parts":[[2026]]},"abstract":"<jats:p>Introduction: Pleomorphic sarcoma (PS) is a high-grade soft-tissue malignancy with marked morphologic variability. Divergent differentiation is recognized, but dual smooth-muscle and osteogenic lineage differentiation is exceedingly rare and may mimic other malignancies.\n\nCase Report: A 52-year-old male presented with progressive low-back pain, weight loss, and an enlarging iliac mass. Magnetic resonance imaging showed multiple lytic lesions suggestive of plasma-cell dyscrasia; however, serum electrophoresis was negative. Histopathology revealed high-grade PS, and immunohistochemistry demonstrated simultaneous positivity for smooth-muscle actin and osteocalcin, confirming dual smooth-muscle and osteosarcomatous differentiation. The patient was referred to oncology for multidisciplinary management.\n\nConclusion: PS with dual divergent differentiation represents a rare diagnostic challenge. Clinical and imaging features may falsely suggest hematologic malignancy, underscoring the necessity of correlating radiology, histopathology, and immunohistochemistry.\n\nKeywords: Pleomorphic sarcoma, divergent differentiation, smooth-muscle actin, osteocalcin, iliac lesion, diagnostic dilemma.<\/jats:p>","DOI":"10.13107\/jocr.2026.v16.i05.7277","type":"journal-article","created":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T05:25:06Z","timestamp":1778736306000},"page":"262-266","source":"Crossref","is-referenced-by-count":0,"title":["Undifferentiated Pleomorphic Sarcoma with Dual Smooth-Muscle and Osteogenic Differentiation Mimicking Plasma Cell Dyscrasia: A Rare Diagnostic Pitfall"],"prefix":"10.13107","volume":"16","author":[{"given":"Arnav P","family":"Rathod","sequence":"first","affiliation":[{"name":"Department of Orthopedics, Dr. Panjabrao Deshmukh Memorial Medical College and Hospital, Amravati, Maharashtra, India."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hrishikesh S","family":"Saodekar","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Dr. Panjabrao Deshmukh Memorial Medical College and Hospital, Amravati, Maharashtra, India."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yogesh B","family":"Rathod","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Dr. Panjabrao Deshmukh Memorial Medical College and Hospital, Amravati, Maharashtra, India."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajendra","family":"Baitule","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Dr. Panjabrao Deshmukh Memorial Medical College and Hospital, Amravati, Maharashtra, India."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ganesh","family":"Pundkar","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Dr. Panjabrao Deshmukh Memorial Medical College and Hospital, Amravati, Maharashtra, India."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"5271","published-online":{"date-parts":[[2026]]},"container-title":["Journal of Orthopaedic Case Reports"],"original-title":[],"deposited":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T05:25:06Z","timestamp":1778736306000},"score":1,"resource":{"primary":{"URL":"https:\/\/jocr.co.in\/wp\/2026\/05\/undifferentiated-pleomorphic-sarcoma-with-dual-smooth-muscle-and-osteogenic-differentiation-mimicking-plasma-cell-dyscrasia-a-rare-diagnostic-pitfall\/"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026]]},"references-count":0,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2026]]},"published-print":{"date-parts":[[2026]]}},"URL":"https:\/\/doi.org\/10.13107\/jocr.2026.v16.i05.7277","relation":{},"ISSN":["2321-3817"],"issn-type":[{"value":"2321-3817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026]]}}}