Diagnosis of pulmonary nodules in the cancer patient: the role for routine culture and an unusual application of the human tumor colony-forming assay.

Many solid tumors that occur in humans tend to metastasize to the lungs. The etiology of pulmonary nodules in cancer patients, therefore, presents a diagnostic problem that can be resolved only by histologic evaluation or resection. We present two cases of cancer patients with preoperative and intraoperative diagnoses of metastatic lung tumors. Tissue culture using the Human Tumor Colony-Forming Assay (HTCFA), a procedure that predicts chemosensitivity patterns of tumors, was employed to successfully diagnose those nodules as fungal infections. In one case, results using the HTCFA were crucial in the identification of the opportunistic organism. These cases stress the importance of routine culture of all pulmonary nodules and present an unusual but noteworthy application of the HTCFA system.