Chromosomal changes in somatic cells in seminoma patients after treatment with ionizing radiation or cytostatics.
Seminomas are sensitive to both ionizing radiation and cytostatic drugs. The study's objective was to find out the effects of cytostatics or ionizing radiation by comparing the results of genome testing before treatment and immediately afterwards. Repeat cytogenetic testing six months after completion of treatment was used to find out changes resulting from reparatory processes after various types of treatment and the degree of elimination of defective lymphocytes from circulation. Three cytogenetic tests were used in our study to find out structural changes in chromosomes (percentage of aberrations), sister chromatid exchanges (SCE) and the number of micronuclei in binuclear lymphocytes (MN). In patients treated with ionizing radiation, strong inhibition of the mitotic activity of lymphocytes occurred after irradiation of para-aortal and ipsilateral inguinal lymph nodes. However, it is difficult to make a connection between the mitotic activity of lymphocytes and their total number, which was found to be within a normal range throughout the study. There is, therefore, another possibility, i.e. that this process actually involves impairment of intracellular enzymes and blockage of the synthesis of macromolecules in lymphocytes which have suffered a large degree of genome damage. Six months after a completed course of irradiation, mitotic activity was found to be mostly normal; however, there was still a very high percentage of aberrations compared with group II (patients treated with a cytostatic, paraplatin) or with respect to the control group, in which the average percentage of aberrations was 1.42 (excluding dicentrics and rings, which are found in all irradiated patients). From the cytological-mutagenetic point of view, chemotherapy proved to be less aggressive to patients. The results of recovery were visible earlier and the elimination of damaged cells was quicker.
Bilban-Jakopin
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Department of Radiation Oncology, Institute of Oncology, Ljubljana, Slovenia. tina.bilban@siol.net
D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use; D016190:Carboplatin / Q000627:therapeutic use; D016022:Case-Control Studies; D017024:Chemotherapy, Adjuvant; D002869:Chromosome Aberrations; D006801:Humans; D008297:Male; D015162:Micronucleus Tests; D011446:Prospective Studies; D018714:Radiotherapy, Adjuvant; D018239:Seminoma / Q000188:drug therapy / Q000235:genetics / Q000532:radiotherapy* / Q000601:surgery; D012854:Sister Chromatid Exchange / Q000528:radiation effects*; D013736:Testicular Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000532:radiotherapy* / Q000601:surgery
D000970:Antineoplastic Agents; D016190:Carboplatin