Impact of topotecan-based chemotherapy on the immune system of advanced ovarian cancer patients: an immunophenotypic study

The effects of topotecan-based chemotherapy (CT) on peripheral blood lymphocyte (PBL) subsets were evaluated in ovarian cancer patients. Fourteen patients with epithelial ovarian cancer, at the diagnosis or relapsed after platinum-based CT, were treated with: a) topotecan in association with carboplatin and taxanes as first line CT; b) topotecan alone or c) topotecan in association with carboplatin both as second line of treatment after platinum. The phenotype of PBL was determined before starting treatment and immediately before each CT course by flow cytometric analysis. Before starting CT, the absolute number of lymphocytes and the CD2+, CD3+, CD4+ subsets were significantly lower in pre-treated patients and not significantly altered in CT-naive patients with respect to a cohort of 20 healthy donors utilized as control. Lymphocytes co-expressing CD4+/CD8+ were significantly higher in both subgroups of patients than in normal donors. CD4+/CD45RA+ and CD4+/CD45RO+ subsets were significantly decreased in pre-treated patients and normal in CT-naive patients. CD3+/HLA-DR+ T cell population significantly increased in CT-naive patients at baseline. During CT and after its discontinuation, no relevant changes were recorded for both subgroups of patients with respect to the baseline in lymphocyte absolute count, CD2+, CD3+, CD4+, CD4+/CD45RO+ subsets, while CD4+/CD45RA+ subpopulation was significantly decreased in CT-naive patients. CD8+, CD19+, CD20+, CD16+, CD56+, CD2+/CD25+ subsets did not differ statistically comparing to normal donors both at baseline and during CT. The treatment was well tolerated and no patient developed non-neutropenic infection. Topotecan-based therapy does not have a negative impact on PBL in either CT-naive or in pretreated ovarian cancer patients. This information should be considered when utilizing topotecan with other anticancer drugs in the adjuvant setting as well as when dose-intensification of topotecan with stem cell support is planned.