Inhibin-alpha subunit is an independent prognostic parameter in human endometrial carcinomas

Inhibins are dimeric glycoproteins, composed of an alpha-subunit (inhibin-a) and one of two possible beta-subunits (bA or bB), with substantial roles in human reproduction and in endocrine-responsive tumours. Aims of this study were to determine the distribution of inhibin-a, -bA and -bB in malignant human endometrial tissue and the assessment of an association with specific clinicopathologic tumour features and clinical outcome. A series of 302 endometrial cancer tissue samples were immunohistochemically analysed with monoclonal antibodies against inhibin-subunits. The inhibin-a subunit showed a significant association with histological grading, surgical staging, lymph node status and diabetes in patients with endometrial cancer. Interestingly, loss of inhibin-a expression resulted in a poorer survival of endometrial cancer patients. Additionally, survival analysis demonstrated that inhibin-a immunoreactivity was an independent prognostic factor for progression-free survival, cause-specific survival as well as overall survival. In contrast, although inhibin-bA- and -bB subunits showed a significant association between endometrial histological subtypes and histological grading, both subunits were not found to be associated with survival in endometrial cancer patients. Therefore, inhibin-a immunostaining might be used as a simple and efficient marker to identify high-risk patients leading in the selection of patients for an aggressive adjuvant therapy.

cancer - endometrium - immunohistochemistry - inhibin-betaB - inhibin-alpha - inhibin-betaA - prognosis - survival