Adenoid squamous cell carcinoma of the larynx: an uncommon histological variant of squamous cell carcinoma

Adenoid squamous cell carcinoma (ASCC) or acantholytic squamous cell carcinoma is a well-recognized variant of squamous cell carcinoma. ASCC commonly occurs in the sun-exposed areas of the skin and has only rarely been observed in mucosal sites. We report a case of ASCC in the larynx of a 75-year-old man with a history of odynophagia and dysphonia of 3 months' duration that presented as an exophytic lesion on the right vocal cord. Biopsy was performed and the histological diagnosis was squamous cell carcinoma. Treatment consisted of total laryngectomy and radical neck dissection. Microscopically, the tumor showed a prominent alveolar pattern with cystic degeneration of the neoplastic epithelium and formation of pseudoglandular structures. In the lumina there were acantholytic cells. Transition areas from conventional squamous cell carcinoma to adenoid pattern were found. To the best of our knowledge this is only the third case of ASCC reported in the larynx. We reviewed the nine mucosal ASCCs of the upper aerodigestive tract reported. The assertion that these tumors are associated with an aggressive behavior and poor prognosis cannot be estimated in this review as the number of cases is small and the tumors are located in different places.