An evaluation of chromatin condensation and DNA integrity in the spermatozoa of men with cancer before and after therapy.

Cancer has been known for a long time to have a depressive effect on sperm number and quality. Cytotoxic agents and radiotherapy have also been shown to impair spermatogenesis. The aim of this study was to assess DNA integrity and chromatin condensation in the spermatozoa of men with cancer before and after treatment. Chromatin condensation was evaluated using flowcytometric assessment with propidium iodide, DNA integrity was determined using the comet assay. Thirty-three men with cancer (testicular cancer, lymphoma and leukaemia) and 14 men with proven fertility took part in the study. The study found that in men with cancer, the percentage of spermatozoa with highly condensed DNA was less than that of controls. DNA integrity when assessed using the comet assay was also reduced by cancer. Percentage head DNA intact and percentage of condensed chromatin in the spermatozoa of men with cancer after treatment were less than those in fertile men. This study, although small, does demonstrate a detrimental effect on chromatin condensation and DNA integrity of cancer and its treatment. These findings are important because of the potential effects impaired chromatin and DNA integrity could have on fertilization, blastocyst and embryo development.