RESUMEN
We report a rare case of lymphangitis carcinomatosa in a 66-year-old man with a relatively long survival of 18 months following chemotherapy.The patient initially presented with dyspnea and lower abdominal pain.Subsequent colonoscopy detected adenocarcinoma of the descending colon, and computed tomography (CT) demonstrated indications of lymphangitis carcinomatosa of the lung.Therefore, the patient was diagnosed with pulmonary metastasis due to colon cancer and administered chemotherapy.The performance status (PS) of patients with lymphangitis carcinomatosa is usually dismal.This patient's PS was also poor, but dyspnea markedly improved following chemotherapy, and a subsequent CT revealed disappearance of radiological findings of lymphangitis carcinomatosa.However, subsequent immunocytochemistry analysis using the cell transfer method in bronchoalveolar lavage fluid specimens revealed diffuse positivity for cytokeratin (CK) 7, while the colon carcinoma was negative for CK7.The difference in CK7 immunoreactivity between the bronchoalveolar lavage fluid and biopsy specimen of the colon indicated that the lymphangitis carcinomatosa in this patient could be reasonably postulated to be caused by a synchronous primary pulmonary adenocarcinoma with intestinal differentiation.However, an autopsy could not be performed to test this hypothesis.