Endocrine Abstracts

Introduction: As observed clinically, the development of pituitary tumours and the probability of their recurrence after neurosurgery tend to be unpredictable. The aim of this work was to evaluate Ki-67 and nuclear and plasmatic prothymosin alpha indices as potential pathological markers to predict the aggressiveness of pituitary adenomas.

Material and methods: Ki-67 and prothymosin alpha indices were determined by immunochemistry in specimens excised from neurosurgically removed pituitary tumours. Histopathological material was examined from 30 patients with pituitary macroadenoma (17 females and 13 males, mean age 58.5±12.5 years.) who underwent pituitary tumour surgery. The median value of maximum diameters of tumours was 25.0 mm (IQR 10.25).

Results: Expression of Ki-67, nuclear prothymosin alpha and plasma prothymosin alpha was revealed only in cells of pituitary tumours (being absent in extra-tumoural tissue) and was present in 80, 80 and 90% of adenomas, respectively. The median values of Ki-67, nuclear prothymosin alpha and plasma prothymosin alpha indices were 1.95% (IQR 2.7) 0.63% (IQR 3.5) and 26.4% (IQR 56.6) respectively. The indices of Ki-67 and prothymosin alpha (nuclear and plasma) were not significantly different in adenomas with positive anterior pituitary hormone expression (n=20) as compared with adenomas with negative anterior pituitary hormone expression (n=10). Neither Ki-67 nor prothymosin alpha (nuclear and plasma) indices were found to be significantly correlated with tumour size or patient age. We found no correlation of any of the above-mentioned indices with expression of pituitary hormones in the examined specimens.

Conclusion: Expression of Ki-67 and prothymosin alpha was stated in the majority of pituitary adenomas. Ki-67 and prothymosin alpha, as determined in pituitary tumour specimens, was not related to tumour size nor to the type of pituitary hormone expression.