Primary rhabdomyosarcoma of the distal femoral diaphysis: a case report and review of the literature

Abstract

Primary rhabdomyosarcoma of the bone is an extremely rare condition with few examples reported in the literature. We present the case of a 34-year-old male who presented with a lesion in the distal femur with initial imaging features consistent with Ewing sarcoma. Histologically, the lesion consisted of atypical pleomorphic polygonal rhabdomyoblasts demonstrating focal desmin and myogenin expression. A diagnosis of pleomorphic rhabdomyosarcoma was rendered. Despite systemic treatment and surgery, this patient experienced a rapidly progressive disease course. We believe this is only the second report in the orthopedic literature of a case of primary pleomorphic rhabdomyosarcoma of the bone. The key imaging, pathologic, and clinical findings are discussed.

Spindle cell rhabdomyosarcoma of bone with FUS–TFCP2 fusion: confirmation of a very recently described rhabdomyosarcoma subtype

“…Primary rhabdomyosarcomas of bone are exceedingly rare, with fewer than 10 credible reported cases of osseous rhabdomyosarcomas of embryonal, alveolar or pleomorphic subtype . There is one report, by Oda and colleagues, of a primary rhabdomyosarcoma of the iliac bone in an adult (described as resembling ‘fibrosarcoma’), which appears to us to most probably represent spindle cell rhabdomyosarcoma …”

Femoral intraosseous rhabdomyosarcoma: a case report and literature review

“…Pathological fracture is frequently found on bone rhabdomyosarcoma. We found 14 cases (7,(9)(10)(11)16,18,19) evolved with pathological fracture after or during diagnostic investigation. In all of these cases, the tumor was present in the femur, four diaphyseal (7,11,16,17) and one located in the distal region of the femur.…”

“…The literature review has shown few reports of primary bone RMS. (1,7,(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) Of the fifteen cases presented so far (including this one), two did not have a specified subtype and one of them did not give access to full data (Table 2). The ERMS and ARMS subtypes were concentrated in younger patients while all pleomorphic subtypes were diagnosed in patients over 30-years-old.…”

“…This set of characteristics is common to a variable range of sarcomas and not specific for RMS diagnosis. (7) Currently, the recommended treatment for RMS is multimodal with surgery, chemotherapy, and radiotherapy. The survivorship with this kind of treatment on children with localized disease may be greater than 60%.…”

Primary alveolar rhabdomyosarcoma of retrorectal-presacral space in an adult patient

“…Imaging findings of RMS are nonspecific. [6] The tumors may appear isointense and low signal intensity to surrounding skeletal muscle on T1-weighted MRI, high and heterogeneous signal on T2-weighted images and contrast-enhanced to variable degrees on T1-weighted sequences. [15,16] Alveolar subtypes, in particular, may show areas of hemorrhage and necrosis as well.…”