Palliative radiotherapy in a patient with pulmonary adenoid cystic carcinoma.

Primary adenoid cystic carcinoma in the lung is very rare, so its clinicopathologic characteristics have usually been extrapolated from the salivary disease. However, the clinical courses of pulmonary adenoid cystic carcinomas may be different from those of salivary disease, and individual differences may also exist. I report here on a case of a patient who was initially diagnosed as pulmonary adenoid cystic carcinoma with liver metastases and the tumor showed extreme radiosensitivity, but it also underwent an aggressive clinical course. Adenoid cystic carcinoma is usually known to be a slowly growing tumor, but it may rapidly disseminate, like in this patient. Therefore, the factors predicting aggressive behavior should be determined and the treatment might be individualized according to the primary sites and on the patient's basis.