1 | INTRODUCTION
Adenoid cystic carcinoma (ACC) is a rare primary neoplasm of salivary
glands which is 1% of all head and neck cancers and 10% of all
salivary gland neoplasms. ACC arises in both major and minor salivary
glands. The parotid gland accounts for 25% of origin in head and neck
which is the most common site. 1 Occasionally it
arises in the nose, the paranasal sinuses, the lachrymal glands, the
ceruminous glands of the external auditory canal, the larynx, the
nasopharynx, and the palate.
Anatomically, ACC of hypopharynx is an extremely rare disease. The most
common histologic type of hypopharyngeal malignancy is squamous cell
carcinoma (SCC), which originates very differently from ACC. Moreover,
treatment backbone of ACC is surgery while the role of radiation and
systemic therapy are still controversial, unlike the treatment strategy
of SCC.
We report the case of a hypopharyngeal ACC presenting several months
after a previous diagnosis of SCC. The
rare incidence and a short time
earlier history of SCC could pose a diagnostic challenge for ACC in
hypopharynx.