Skeletal muscle deposits from primary oropharyngeal carcinoma: A home away from home

Abstract

There have been significant improvements in loco-regional control of head and neck squamous cell carcinoma (HNSCC), but distant metastasis remains a clinically important challenge. The incidence of distant metastasis in HNSCC is quite uncommon, varying from 4% - 26%. The most often involved sites being lung, liver and bone. Several factors influencing the incidence of distant metastasis include primary tumour site, grading, nodal involvement, and status of locoregional disease. We report a case of a 59-year old gentleman with oropharyngeal carcinoma treated 6 months back presenting with swelling over the right infra-scapular region and the medial aspect of lower one third of right thigh resulting from metastasis to skeletal muscle. The results of histology and immunohistochemistry were consistent with a metastasis from a squamous cell carcinoma oropharynx. The disease was staged as stage III initially at the time of presentation. The patient received definitive concurrent chemoradiation therapy to the primary and nodal regions. There was no evidence of locoregional disease after 1 year. In the literature, there are reports of HNSCC metastasizing to different parts of the body. However, this is among the few case report of a metastasis to the skeletal muscle. Keywords: Chemoradiotherapy, Immunohistochemistry, Oropharyngeal neoplasm, Skeletal muscle.