Adult Alveolar Paranasal Rhabdomyosarcoma; A Rare Aggressive Disease with Pulmonary, Brain and Skeletal Metastasis: Review of an Institutional Experience

Rhabdomyosarcoma (RMS) is predominantly seen in children, most commonly occurring in the head and neck region while extremity tumors are more common in adults. An adult onset RMS of nasal cavity and paranasal sinus is of exceedingly rare occurrence accounting for only 1.5% of reported head and neck cases. Adult RMS has worse outcome and survival than children with similar disease. We hereby review a highly aggressive and fulminant case of adult alveolar RMS where a 49-year-old male presented with complaints of left nasal stuffiness and left neck swelling followed by swelling of left cheek and proptosis within two months duration. Radiological imaging scans showed soft tissue lesion involving left nasal cavity extending to left maxillary sinus with intra-orbital and anterior cranial fossa infiltration without any distant organ involvement. Immune-histopathology revealed alveolar-type RMS. He was treated with induction chemotherapy followed by external beam radiotherapy (EBRT). He underwent left maxillectomy and ipsilateral neck dissection but developed local-regional recurrence within three weeks of surgery. While on adjuvant chemotherapy he developed pulmonary, brain and spinal metastasis for which he was palliated with EBRT. However, his condition kept on deteriorating on second line chemotherapy and he finally succumbed to this fulminant illness. With a background of our case, we discuss this disease of paranasal sinuses in adults to highlight its extreme aggressiveness and fulminant behaviour, rarity, the diagnostic and therapeutic challenge it presents, the overall dismal prognosis of this malignancy once dissemination occurs and summarize the recent advances in treatment.