[A case of lung cancer suspected to be pulmonary mycosis of the fungus ball type].

This paper reports a 73-year-old male case of lung cancer presenting as thin-walled cavity which was suspected to be pulmonary mycosis of the fungus ball type. Routine chest X-ray film showed a thin-walled cavity without a round shadow inside it. CR tomogram taken 2 months after the previous plain chest X-ray film showed an irregular thickening of the cavity wall and a round shadow inside it. Pulmonary mycosis of the fungus ball type was suspected based on the CR tomogram. But chest X-ray CT film taken 1 month after the previous CR tomogram revealed that the entire cavity wall was thickened with irregular convexity and no round shadow was seen in the cavity. Cavitary lung cancer was also suspected based on the findings of X-ray CT film. The surgical specimen, obtained by right upper lobectomy, revealed a moderately differentiated squamous cell carcinoma unaccompanied by pulmonary mycosis in the cavity space. Even in cases suggestive of mycosis, aggressive surgical intervention is recommended in those suspected of malignancy.