Background: Rhabdomyosarcoma (RMS) is a malignant soft tissue tumor that accounts for approximately one-half of soft tissue sarcomas in childhood age groups. Metastatic RMS is a rare condition that occurs in less than 25% of patients at diagnosis and can have variable clinical presentations.
Case presentation: Here we report a 17-year-old boy with history of weight loss, fever and generalized bone pain admitted for severe hypercalcemia. The definite diagnosis of RMS was performed with immune-phenotyping of the metastatic lymph-node biopsy. The primary tumor site was not found. His bone scan showed diffuse bone metastasis and significant soft tissue technetium uptake due to extra-osseous calcification.
Conclusion: Metastatic RMS can mimic lymphoproliferative disorders at presentation. Clinicians must be aware of this diagnosis especially in young adults.
Keywords: Extra-osseous calcification; Lymphoproliferative disorder; Metastatic rhabdomyosarcoma.
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