Ex-vivo fine needle aspiration. A new method of xenografting non-small cell carcinoma of the lung.

Ex-vivo needle aspiration (xvFNA) has been rarely used to obtain viable tumor cells. It has been occasionally employed for short-term cultures. Xenografting of lung carcinoma in athymic nude mice provides a good animal model for the study of this neoplasm. Successful engraftment using conventional methods has been disappointing) low (d 40%). Enzymatic digestion of the tumor fragments to obtain cell suspension lowers viability. We postulated that xvFNA might provide readily available tumor cell suspensions for xenografting lung carcinoma and that it would provide a higher success rate of engraftment than the conventional techniques. We aseptically performed xnFNA in 35 cases of freshly resected non-small cell carcinoma of the lung. These included 15 adenocarcinomas, 17 squamous carcinomas and 3 undifferentiated non-small cell carcinoma (UNSCC). Tumor cell suspensions were injected subcutaneously in athymic nude mice. Tumor necrosis in the aspirates ranged from 20-90% (median 60%). Gross evidence of engraftment was seen in 30 of 35 cases (85.7%) 1-19 weeks postimplantation (median 2 weeks). This was seen in UNSCC (3/3), squamous carcinomas (13/17) and adenocarcinomas (14/15). Xenograft sizes ranged from 5-34 mm (median 19 mm). They showed similar morphology to the primary tumors. Ex-vivo FNA used for harvesting lung carcinoma cells and their xenografting is an effective method for obtaining viable material for studying this neoplasm.