[Low-grade papillary adenocarcinoma of the endolymphatic sac. Report of three cases with immunohistochemical study].

Glandular tumors involving the mastoid and the middle ear are rare, and distinguishing between adenoma and adenocarcinoma remains difficult. Among these latter lesions, two distinct patterns are accepted. One of them, the papillary form takes a more aggressive course with wider regional spread and must be separated from the other type, the middle ear carcinoma. Its microscopic appearance and clinical course have been extensively described by Heffner who considered it as "low-grade adenocarcinoma of probable endolymphatic sac origin". A few cases have been associated with von Hippel-Lindau disease. Three cases of papillary adenocarcinoma of endolymphatic sac origin are reported. One concerned an isolated tumor, the two others were associated with von Hippel-Lindau disease. Their clinical, pathological and immunohistochemical data are presented.