Clinical, laboratory, radiological and pathological characteristics of patients with pituitary adenoma

The aim of the study is to evaluate the clinical, laboratory, and pathological data of patients diagnosed with pituitary adenoma. To this end, the demographic, clinical, laboratory, pathology, and radiology data of patients with pituitary adenoma were evaluated retrospectively. A total of 222 patients, including 141 women and 81 men, were included in the study. The mean age of the patients was 48.13±15 years, the mean age at diagnosis was 42.31±15.04 years, and the mean follow-up duration was 4.99±2.84 years. The proportion of patients with incidental adenomas was 11.7% (n=26). Symptoms of mass effect were present in 33% of the patients (n=73). The most common pituitary adenoma was prolactinoma (40.5%) (n=90). Nonfunctional adenoma followed prolactinoma with a rate of 38.7% (n=86). The proportion of patients with pituitary insufficiency at the time of diagnosis was 20.3% (n=45). At the time of diagnosis, 56.3% of the patients (n=125) had macroadenomas, and 43.7% (n=97) had microadenomas. It was found that 45% of the patients (n=100) were initially treated with medical therapy. The proportion of patients who underwent surgery was 28.4% (n=63). 25.2% of the patients (n=56) were monitored without treatment. The most common indication for surgery was functionality, found in 47.4% (n=36) of the cases. Long diameter and optic chiasm compression were the surgical indications in 27.6% (n=21) and 19.7% (n=15) of the cases, respectively. The least common indication was apoplexy, found in 5.3% (n=4). Recurrence during follow-up was observed in 18.9% of all patients (n=42). The proportion of patients who developed new pituitary insufficiency during follow-up was 18.5% (n=41), while 81.1% (n=180) of the patients had stable hormonal functions throughout the follow-up. For patients monitored without treatment, the median value for the longest diameter in the first MRI was 5 mm (3-7.75), while in the last MRI it was 4 mm (2-6.75) (p=0.002). No diameter change was found between the first and last MRI for nonfunctional pituitary adenoma patients using cabergoline. However, the rate of optic chiasm compression decreased after cabergoline use. No significant change was observed between the first and last MRI findings of nonfunctional adenoma patients monitored without treatment. Among patients monitored without treatment, 14.3% had a reduction in size, 60.7% had stable size, 5.4% had an increase in size, and 19.6% had complete resolution. The proportion of men in the acromegaly group (62.5%) was significantly higher compared to the prolactinoma (28.9%) and Cushing (4.8%) groups; the proportion of men in the nonfunctional hormone activity group (45.3%) was significantly higher only compared to the Cushing group. The presence of pituitary insufficiency at diagnosis in nonfunctional adenoma patients was significantly higher compared to patients with prolactinoma, Cushing's syndrome, and acromegaly. The age at diagnosis in the functional group was higher compared to the nonfunctional group (46.5 (39-57) years vs. 38 (27-49) years, p<0.001). The proportion of women in the functional group (69.1%) was significantly higher compared to the nonfunctional group (54.7%) (p=0.029). The 133 frequency of pituitary insufficiency at diagnosis was 37.2% (n=32) in the nonfunctional group and 9.6% (n=13) in the functional group (p<0.001). Our study demonstrates that the age at diagnosis of patients with nonfunctional adenomas is older compared to those with functional adenomas, and that the frequency of women is higher in patients with functional adenomas compared to those with nonfunctional adenomas. Pituitary insufficiency at diagnosis is more frequently observed in patients with nonfunctional pituitary adenomas compared to those with functional adenomas. Keywords: Pituitary adenoma, Prolactinoma, Acromegaly, Cushing's syndrome