[Two cases of multiple primary cancer involving the lung with old pulmonary tuberculosis]

We reported 2 relatively rare cases of multiple primary cancer including lung cancer accompanied by old pulmonary tuberculosis. Patient 1 was a 62-year-old man admitted to our hospital for further evaluation of an infiltrative shadow on chest X-ray films, and a cervical tumor noted 10 years earlier and thought to be thyroid cancer. A Transbronchial lung biopsy (TBLB) specimen disclosed poorly differentiated squamous cell carcinoma. A right upper lobectomy and thyroidectomy were performed. Histopathologic findings showed a neoplastic lesion adjacent to caseous necrosis with formation of granuloma consistent with tuberculosis. Also, the cervical tumor was considered to be a metastatic lymph node from thyroid papillary carcinoma. Patient 2 was a 73-year-old man with a 14-year history of treatment for transitional cell carcinoma of urinary bladder, who had been admitted to our hospital for further evaluation because of a nodular shadow observed on chest X-ray films. TBLB specimens disclosed adenocarcinoma. A right upper lobectomy was performed. Histopathologic findings revealed a neoplastic tumorlet in the same lobe. No detectable increases in serum TNF-alpha, IL-1 beta or IFN-gamma were observed in either patient. Phytohemagglutinin- and concanavalin-A-stimulated lymphocyte proliferation decreased in Patient 1. These findings suggested that the immunocompromised status of patients with cancer in addition to old pulmonary tuberculosis may contribute to the development of lung cancer.