[Diffuse pulmonary meningotheliomatosis: an uncommon cause of the micronodular pattern].

Pulmonary meningotheliomas are rare tumors that manifest as small nodules. They are most common in the sixth and seventh decades of life and are more common in women. Their cause is unknown and the imaging differential diagnosis should include other diseases that course with nodular patterns. Several authors have documented a statistically significant association between pulmonary meningotheliomatosis and diverse lung diseases, with adenocarcinoma of the lung being the most frequently associated disease. Very few cases of radiologically documented meningotheliomatosis have been reported. We present a case of a patient with a history of metachronous breast and rectal cancer. A micronodular pattern was observed in both lungs during CT examination to determine the extent of rectal cancer. The radiologic findings were initially interpreted as metastases and the definitive diagnosis of meningotheliomatosis was reached after lung biopsy.