Prolactin levels and gender are associated with tumour behaviour in prolactinomas but Ki-67 index is not.

INTRODUCTION

The objective of this study was to investigate the effects of some clinical and pathological features of prolactinomas on tumour behaviour.

MATERIAL AND METHODS

The study included 113 patients with prolactinoma (27 male, 86 female), with a mean age at diagnosis of 34.4 ± 10.0 years (40.3 ± 12.6 in males, 32.6 ± 8.3 in females). Patients were grouped as invasive or non-invasive according to radiological imaging findings. Ki-67 levels were evaluated if possible.

RESULTS

The mean adenoma size (longest dimension) was 38.6 ± 21.6 mm and 10.8 ± 9.4 mm in male and female patients. Pre-treatment serum levels of prolactin were defined as mean 1,926 ± 6,662 ng/mL in all, 124.8 ± 63.4 and 4,675 ± 10,049 ng/mL in the noninvasive and invasive groups (p < 0.05). A positive correlation was found between the serum levels of prolactin and tumour size. The rate of patients with Ki-67 ≥ 0.03 was 37.5% and 47.8% in the noninvasive and invasive groups. The reduction rates were 60.8% and 80.4% in tumour sizes and 81.1% and 93.8% in prolactin level in the noninvasive and invasive groups, respectively, (p < 0.05).

CONCLUSIONS

We found a strong correlation between prolactin levels and invasiveness in male patients compared to females. Ki-67 index was not found to have a place in defining the prognosis.