Abstract
Background. Cavitary lesions rarely form in patients with lung cancer, and thin-walled cavities are particularly rare. Case. A 55-year-old man had suffered from a lung abscess; a previous chest CT scan had already revealed a 14-mm cystic lesion in S2a of the right lung. Three years later, he was re-admitted to our hospital because the cystic lesion in the right S2 had increased in size. A chest CT scan on admission showed a large, 77-mm mass shadow with thin-walled cavitation in the right S2-S6, with partial hypertrophy on the caudal side and many intrapulmonary nodules with thin-walled cavitation. Transbronchial biopsy revealed squamous cell carcinoma. After three cycles of chemotherapy with cisplatin and docetaxel, the wall of the primary lesion and almost all of the metastases had become thinner, resulting in cyst-like shadows. While a number of hypotheses have been proposed regarding the mechanism behind thin-walled cavitation in lung cancer, we suspected that the thin-walled cavity in the present case developed through a check valve mechanism. Conclusion. Careful follow-up is indispensable in patients with pulmonary thin-walled cavities due to the possible development of lung cancer.
