Clinicopathological Role of Progesterone Hormone in IDH-Mutant Astrocytoma.

Context: Sex steroid hormones can influence astrocytomas, the most common form of glioma. Progesterone (P) may participate in cancer development. The current study evaluated the progesterone receptor (PR) expression in 49 (isocitrate dehydrogenase (IDH) mutant) astrocytomas concerning their proliferative potential.

Aim: The current study aimed to assess the immunohistochemical progesterone expression in IDH-mutant astrocytic tumors besides correlating such expression with the pathological parameters of the tumors.

Settings and design: This is a retrospective observational cross-sectional study.

Materials and methods: Forty-nine intracranial astrocytoma specimens were evaluated for PRs and isocitrate dehydrogenase (IDH) enzyme mutations in a histopathological and immunohistochemical study.

Results: The study included 26 females (53.1%) and 23 males (46.9%) (n = 49). The median age was 41.5 (27.75) years. IDH-mutant astrocytic tumors demonstrated positive PR immunoreactivity in 42 of 49 cases (85.7%). Its expression was observed in 20 of 27 cases of Grade 2 astrocytomas (diffuse type), 7 of 7 cases of Grade 3 astrocytomas (anaplastic type), and 15 of 15 cases of Grade 4 astrocytomas (glioblastoma). In addition, tumor vessel walls and cells with microvascular endothelial proliferation showed PR positivity. Furthermore, there was a significant increase in PR expression in the right and left-sided tumors compared to midline tumors and in supratentorial tumors compared to infratentorial tumors. It was high with positive necrosis. The tumor grade and the expression of PR were strongly positively correlated (r = 0.972; P < 0.001), and there was a moderately positive linear correlation between them and the patient's age (r = 0.414; P = 0.003). Recurrence and gender were not associated with PR expression.

Conclusion: We propose a correlation between PR and the histologic grade, growth, and angiogenesis of the IDH-mutant astrocytoma. As a result, it can act as a prognostic marker for a new promising target therapy.