A Case of a Giant Pulmonary Bulla with Lung Cancer-associated Regression

Abstract

Background. Primary lung cancer frequently arises from the wall of the emphysematous bullae, and the same is true for giant pulmonary bullae. Although the clinical course of a giant pulmonary bulla is diverse, it most often increases in size or remains unchanged. The natural regression of a giant pulmonary bulla is rare and the underlying mechanism is unknown. We herein report the case of a patient who experienced the sub-total regression of a giant pulmonary bulla in association with the development of primary lung cancer. Case. The patient was a 72-year-old man, whose main complaint was discomfort on the left side of his back. Computed tomography (CT) showed a 4-cm lung tumor on the apex of the left lung, which was suspected to be invading the parietal pleura. Ten years previously, chest CT had shown an 11-cm giant pulmonary bulla at the same location, which now presented as a 3-cm pulmonary bulla accompanied by a cancerous mass. Left upper lobectomy, with resection of the parietal pleura and lymph node dissection, was performed. The pathological and CT findings indicated that the pulmonary bulla had regressed due to the inhibition of airflow into the giant pulmonary bulla, as a consequence of the development of lung cancer on or near the bulla wall. Conclusion. The results of the CT examination and the pathological findings were indicative of the mechanism of regression of a giant pulmonary bulla in association with the development of primary lung cancer.