Purpose: Stem cell factor receptor (c-kit) plays a crucial role in regulating proliferation and survival of germ cells. The aim of this study was to find the correlation between the number of c-kit positive germ cells, testicular asymmetry and histological grade in varicocele affected testis samples of adolescents.
Materials and Methods: Twenty testicular biopsy samples of adolescents affected by varicocele and eight normal control testes were included. The relationship between percentage of testicular asymmetry, number of tubular c-kit positive germ cells and severity of spermatogenic failure was assessed by Spearman correlation test. The results of each group were compared by Mann–Whitney-U test. A p < .05 was considered as statistically significant.
Results: The mean (SD) histological grade for spermatogenic failure in controls was 1.37(0.52), median 1, while in the varicocele group, it was 2.70(1.08), median 3 (p= .0052). Mean(SD) number c-kit positive germ cells in the control group were 20.1(2.52), median 20, while in the varicocele group it was 12.35(7.16), median 12.5 (p= .0059). Spearman test documented a significant positive correlation between percentage of hypotrophy and histological grade of spermatogenic failure (r = 0.5544 , 95% CI: 0.1345 to 0.8055, p = .0112) but a negative correlation with the number of c-kit positive cells (r = - 0.5871, 95% CI: - 0.8219 to -0.1817, p = .0065). Moreover, a significant negative correlation was found between grade of histological changes and number of c-kit positive germ cells (p< .0001).
Conclusions: A significant correlation between hypotrophy, histological lesions and c-kit positive germ cells exists in varicocele testes. This finding suggests a possible role for c-kit in the pathogenesis of germ cell impairment in varicocele. Histological changes and lack of c-kit germ cells were also noted in testes not displaying hypotrophy. We believe that reliable markers should be found as better predictors of testicular function in adolescent with varicocele.
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