The association of MCM7 and CD117 expressions with stem cell markers (CD34, CD44) in uterin leiomyomas and leiomyosarcomas and with prognostic parameters in uterin leiomyosarcomas

Leiomyosarcomas are malignant smooth muscle tumors. Uterine leiomyosarcomas usually have an aggressive clinical course and poor prognosis. Their 5-year overall survival rates vary between 20% and 30%. Beside several parameters i.e: the age of the patient, the diameter of the tumor, the characteristics of macroscopic cross section, the boundary of tumor, vascular invasion, the degree of nuclear atypia, coagulative necrosis, increased mitotic activity, atypical mitosis and Ki-67 proliferation index are helpful in differentiation from atypical leiomyomas, and smooth muscle tumors of uncertain malignant potential. In addition, there are several studies concerning CD44 and c-kit expression in uterine leiomyosarcomas. But there are no studies about CD34 and MCM7 (Miniature chromosome maintenance) expression in uterine leiomyosarcomas. The aim of this study was to search the expression of CD117, CD34, CD44 and MCM7 in different groups of benign and malign uterin mesenchymal tumors and its relation with tumor types and prognostic parameters. Histologic sections of paraffin blocks of 25 leiomyomas(LM), 16 uterin leiomyosarkomas (LMS), 8 smooth muscle tumors of uncertain malignant potential (STUMP), 4 atypical leiomyomas (ALM) and were immunostained with CD117, CD34, CD44, MCM7 antibody. Staining distribution as focal (1-50%) and diffuse (>50%) for evaluation of MCM7 and CD44. CD117 assessment for peritumoral and intratumoral areas in 50 high power fields (BBA) positively stained cells were counted. CD34 assessment for peritumoral and intratumoral areas in 10 high power fields (BBA) positively stained single cells and lumen were counted separately. Comparative analysis of all groups "Kruskal-Wallis ANOVA test", bilateral cross-comparison of the group "Wilcoxon-Mann-Whitney U test", for categorical data "Chi-square test" was used. Focal or diffuse staining with CD117 was not observed. However, in peritumoral and intratumoral areas, between groups in terms mast cells statistically significant difference was observed. In particular, the number of mast cells in the LMS group was significantly lower than the other groups. CD34 staining was observed in peritumoral areas statistically significant difference between the groups in terms of a single cell. Significant difference between the groups in comparison with MCM7 staining was detected. However, no significant difference between the groups with CD44. Also in grade 2 and grade 3 LMS subgroups were significant in terms of MCM7 staining. There was no significant difference between stage, necrosis, size, mitosis, Ki-67 proliferation by CD117, CD34, CD44, MCM7. The result; In all groups, in terms of MCM7, mitosis and Ki-67 were significant differences in the manner consistent with the literature. MCM7 was investigated in another group of tumors in the literature. Uterine sarcomas are no studies associated with MCM7 status. MCM7 was indicated that is a more useful and beneficial to the Ki-67 in terms of tumor proliferation and patients prognosis in literature. MCM7 was significant between low and high grade LMS in our study group. In our retrospective study, we evaluated according to the recurrence of the cases; especially early stage (stage 1-2) in terms of disease-free survival time was identified as the most important prognostic factor.