Background & objective: Pulmonary lymphangitic carcinomatosis (PLC) is a special type of pulmonary metastasis of carcinoma. It is easy to be misdiagnosed as other pulmonary interstitial diseases. This study was to discuss the clinical features of PLC, and provide experience information for diagnosis, differentiated diagnosis, and evaluation of prognosis of PLC.
Methods: A retrospective comparison analysis was performed on 43 PLC patients with pathologic diagnosis and 46 patients with other pulmonary interstitial diseases with clear etiology in the first affiliated hospital of Sun Yat-sen University within the past decade.
Results: In PLC group, 20 patients were found with primary lung cancer; 23 patients were found with primary non-pulmonary carcinoma: 9 cases of breast cancer, 8 cases of large intestinal carcinoma, and 6 cases of gastric carcinoma. The changes of imaging included linear and radiating appearances from the hilum to the outer part even extending to the pleura with nodules, ground-glass opacity of the lung. Enlargement of lymph nodes in mediastinum was present in 51.2% (22/43) and that in pleural effusion was present in 53.5% (23/43) of patients. Extrapulmonary manifestations (metastasis) included 19 cases (44.2%) of lymph nodes to the supraclavicular region, axillary fossa, and post-peritoneal region, 15 cases (34.9%) to the pleura, 9 cases (20.9%) to the bones, 6 cases (14.0%) to the liver, 3 cases (7.0%) to the pericardium, and 3 cases (7.0%) to the brain. The elevated serum level of CEA was commonly observed (23/43, 53.5%). Respiratory manifestations of PLC, such as coughing, panting, dyspnea, and so on, could not be cured by anti-spasm treatment. The development of PLC was so progressive that 31 patients (72.1%) were followed for only 2-7 months before death. The changes of imaging in other pulmonary interstitial disease group included irregular linear or reticular appearances, enlargement of lymph nodes in the mediastinum and hilum, and extrapulmonary manifestations like pleural effusion were not observed. Respiratory manifestations, such as coughing, panting, dyspnea, and so on, could be cured by anti-spasm treatment. Moreover, the development of PLC was relatively slow.
Conclusions: PLC often occurs in patients with primary carcinoma in lung, breast, large intestine, stomach, and so on. More attention should be paid to the diagnosis of PLC in patients who have pulmonary interstitial lesions as described above, and whose respiratory symptoms could not be relieved by anti-spasm treatment and developed progressively. The prognosis of PLC is poor.