[Pulmonary mass suspected as malignant tumour. Thoracic wall abscess and fistula after pulmonary segmental resection].

A 31-year-old patient presented with chronic cough and thoracic pain. A pulmonary mass was seen on chest x-ray, and pulmonary segmental resection was done. Histopathologically, a pulmonary abscess cavity due to actinomycosis was found. Three months later, recurrence of actinomycosis at the thoracic wall was observed. Antibiotic therapy with penicillin was administered. Five months later, with the patient receiving continued antibiotic therapy, a thoracic wall abscess and fistula was diagnosed. Four weeks after abscess drainage and repeat intravenous antibiotic therapy, the patient was symptom-free and had remained symptom-free at 10 months of follow-up.