Polypoidal carcinosarcoma of the oropharynx: a clinicopathological and immunohistochemical study.
Polypoidal squamous cell carcinomas, with a sarcomatous stroma, in the upper aerodigestive tract are very rare but well described tumours. They are associated with a multifarious nomenclature because of different opinions regarding their histology and histogenesis. The main issue is whether the stroma component is a true sarcoma or a benign reactive lesion. In order to draw the attention of otolaryngologists and pathologists to the characteristic features of this rare tumour, two cases originating from the oropharynx are presented. Both tumours were pedunculated and polypoidal, and their bulk consisted of a bizarre sarcoma-like stroma covered with granulation tissue. In some areas of the surface, however, atypical squamous cell epithelium with foci of invasive carcinoma was found. In the vicinity of the latter both tumours contained areas of adenocarcinoma. After surgical excision followed by radiation therapy, there was no recurrence after two and five years, respectively. The histological and immunohistochemical findings support the assumption that these two tumours are carcinosarcomas. Adenocarcinomatous elements in this type of tumour have to our knowledge been reported only twice previously and have never been observed in the pharynx.