EFFICACY OF IFOSFAMIDE AND VP-16 （ETOPOSIDE） IN PATIENTS WITH SMALL CELL LUNG CANCER AND THE CORRELATION BETWEEN MICROVESSEL COUNT ON CHEMOSENSITIVITY

Objective： To evaluate the efficacy of ifosfamide and etoposide （VP-16） in patients with small cell lung cancer （SCLC）, and investigate the correlation between microvessel count （MVC） in tumor and chemotherapeutic sensitivity. Methods： Forty-one consecutive cases of SCLC received chemotherapy of ifosfamide plus VP-16, and underwent investigation retrospectively. Immunohistochemistry using anti-human blood type H monoclonal antibody was conducted and MVC was recorded under light microscope. Results： There were 27 limited-disease and 14 extensive-disease patients. The overall response rate was 92.7% （38/41） with 28 cases （68.3%） of complete response （CR）, 10 （24.4%） with partial response （PR）, 3 （7.3%） with progressive disease （PD）. The 1-, 2-, 3-, and 5-year survival rates were 68.3% （28/41）, 48.3% （20/41）, 23.7% （9/38） and 11.1% （3/27）, respectively, with the median survival of 26.8 months. The principal toxicities were grade 3-4 neutropenia in 8 cases （19.5%）, grade 3-4 thrombocytopenia in 6 cases （14.6%）, mild liver toxicity in 7 cases （17.0%） and mild renal function damage in 4 cases （9.8%）. The mesenchymal vasculature was clearly visualized, with the mean value of 34.7 under each high microscopic power field. Of SCLC with more MVC （n=26）, CR accounted for 84.6%; while in cancers with less MVC （n=l 5）, CR took up 40.0%, with significant difference （P〈0.05）. Conclusion： Administrating ifosfamide and VP-16 is in accordance with the biological features of SCLC and results in beneficial results as well as acceptable side effects. The MVC is positively correlated with the chemotherapeutic sensitivity, and serves as a vital factor contributing to chemosensitivity.