Alveolar rhabdomyosarcoma of the paranasal sinuses with delayed diagnosis in a resource-constrained clinical setting: a case report.

Alveolar rhabdomyosarcoma (ARMS) is the most aggressive subtype of rhabdomyosarcoma. Prognosis is closely linked to anatomical location, with parameningeal involvement and distant metastasis being associated with poorer outcomes. Diagnosis is challenging and requires immunohistochemistry, RT-PCR, and FISH. We report the case of a 17-year-old Peruvian male diagnosed with ARMS who presented with multiple adverse prognostic features, including parameningeal-paranasal disease, orbital invasion, distant metastasis, and PAX3-FOXO1 fusion. The clinical trajectory rapidly progressed and the patient succumbed. This case highlights not only the biological aggressiveness of ARMS, but also the systemic delays in diagnosis that may occur in resource-limited settings. Its educational value lies in raising awareness about diagnostic inequity in pediatric oncology and emphasizing the need for early suspicion and timely referral in atypical clinical presentations.