Investigation of prolactin level and mass size in patients with prolactinoma using cabergoline

Introduction and Aim: Prolactinoma, which originates from lactotroph cells of the pituitary gland and secretes prolactin, is the most common functional pituitary tumor and is generally benign. Unlike other pituitary adenomas, the first choice in prolactinoma is medical treatment. With the dopamine agonists (DA) used in the treatment, the reduction in prolactin hormone levels and the continuation of the normalization provided improvement in patients' symptoms, improvement in quality of life and reduction in mass size. In this study, our aim is to examine the change in prolactin level and mass size in patients with prolactinoma using cabergoline. Materials and Methods: A total of 93 male and female patients between the ages of 18-80 were accepted in a retrospective study conducted with patients diagnosed with prolactinoma who applied to the Endocrinology and Metabolism Clinic of Bezmialem Vakıf University Hospital between 2010-2019. Cabergoline treatment was initiated in these patients diagnosed with prolactinoma. Prolactin hormone levels were examined every three months (0, 3, 6, 9, 12 months) in the outpatient clinic follow-ups under initial and cabergoline treatment. Prolactin hormone levels checked every 3 months in people who use their treatment regularly were observed in the normal (5-20 ng / ml, upper limit 25 ng / ml for women) and suppressed (<5 ng / ml) were included in the study, and those who had prolactin levels above normal in their follow-up patients were not included in the study. As stated, patients were divided into suppressed and normal groups according to the course of prolactin levels. The long axis of the mass detected in pituitary MRI for the diagnosis of prolactinoma was evaluated and the initial mass size (mm) and the size of the mass examined in the 12th month of the treatment were recorded in Statistical Package For Social Sciences for Windows (SPSS). Those less than 10 mm in size were evaluated as microadenoma, those with 10 mm and above as macroadenoma. At the end of one year treatment with cabergoline treatment, it was examined whether there was a regression in the size of the mass in the MRI. In patients with suppressed and normal prolactin levels during their follow-up, the reduction rate (%) of the mass was calculated and compared with each other. Results: In the patients included in this study; when the rate of change in mass size occurring at the end of treatment in patients with suppressed prolactin level and normal group was compared, it was found that the mass decreased significantly more in the suppressed group (p = 0.013). When we consider only female patients, it was observed that the rate of decrease in the size of the mass was significantly higher in the suppressed group among women (p = 0.013), but this relationship was not established in male patients (p = 0.548). When the size of the mass before treatment was examined, the initial prolactin levels in patients with macroadenoma were found to be significantly higher than those with microdenomas (p = 0.001). When we look at the rate of decrease in the size of the mass after one year of treatment, no statistically significant difference was observed between microadenoma and macroadenoma. However, when the patients with microadenomas were examined separately, it was observed that the reduction in mass size was significantly higher in the suppressed group compared to the normal group (p = 0.004). Conclusion: In this study, the rates of reduction in mass size that occurred with cabergoline treatment were compared between those with prolactin suppression and those with prolactin within the normal range. In the prolactin suppressed group, the rate of reduction in mass size was 52.78% after one year of treatment, and 35.60% in the normal group, which was statistically significant. (p = 0.013).