RESUMEN
Rhabdomyosarcoma is a rare and highly aggressive malignancy arising from the striated skeletal muscle fibre. It is commonly a childhood tumour and rarely seen in adults. The most predominant part commonly involved is head and neck. We are reporting a rare case of a 54 year old adult male with Rhabdomyosarcoma of nasopharynx with a non specific presentation of weight loss for past four months, fever, a perianal abscess and backache since 10 days. The haematological and biochemical parameters were within normal limits however C reactive protein and erythrocyte sedimentation rate were raised. An MRI for the pelvis, which was done for the extension of perianal abscess, also displayed some heterogeneous marrow signal, which raised the suspicion of some infiltrative process. Later, a bone scan, PET scan, and a biopsy of the nasopharaynx was done. The biopsy confirmed the findings of Rhabdomyosarcoma by showing marked pleomorphism with strong positive desmin and myogin stain. The patient was then referred to the oncology department for further management.