A high number of tumor-infiltrating lymphocytes are associated with a small tumor size, low tumor stage, and a favorable prognosis in operated small cell lung carcinoma

Tumor-infiltrating lymphocytes, apoptosis, and angiogenesis have a pivotal role in tumor growth control. This study was undertaken to analyze the asso ciations of these factors and their role in the prognosis, defined as survi val time, of 56 patients operated on for small tell lung carcinoma (SCLC), Immnunohistochemically detected T cells and macrophages were the most abund ant tumor-infiltrating lymphocytes in SCLC, whereas the number of B cells w as small, There was a trend in the number of intratumoral cytotoxic/suppres sor CD8 cells that were associated with the extent of apoptotic bodies in S CLC, as measured by in situ 3'-end labeling of apoptotic DNA, A high number of intratumoral T cells and CD8 cells were associated significantly with a low tumor size (<3 cm) and low tumor stage (stages l-H), A high number of intratumoral macrophages were associated with a low tumor stage and angioge nesis, as measured by microvessel density. A high number of T cells, CD8 ce lls, and macrophages and a low tumor size (<3 cm) were prognostic markers p redicting favorable survival time of the patients with SCLC.