[Cystic adenoid carcinoma. Apropos of a case with very prolonged survival].

Adenoid cystic carcinoma is an infrequent tumor, but not a rare one. Its primary location is most often the salivary glands, although it can be found in many other organs, including the lung, which is the most frequent site of remote metastasis. The tumor's two main features, which indicate a need for long-term monitoring, are 1) its high level of local aggressivity and rate of recidivism in spite of radical excision, with recurrence sometimes taking place long after the primary tumor appears, and 2) its slow natural history even when disseminated disease is present. Type of tumoral tissue is an important prognostic factor.