12342 Retrospective Multicenter Study Of Prolactinomas In Men

Abstract Disclosure: M.A. Guitelman: None. G. Cardenas: None. A. Rogozinski: None. C. Ballarino: None. M.F. Battistone: None. K. Danilowicz: None. S. Diez: None. P. Fainstein-Day: None. A. Furioso: None. V. Garcia Roel: None. M.S. Gonzalez Pernas: None. D.A. Katz: None. M.G. Loto: None. S. Mallea Gil: None. M.P. Manavela: None. M.S. Martinez: None. K.A. Miragaya: None. P. Slavinsky: None. S. Sosa: None. J. Tkatch: None. G. Tubert: None. M. Vitale: None. M. Glerean: None. Prolactinomas in men: a retrospective multicenter study Introduction and Objectives: prolactinomas in men have recently been included by the World Health Organization as a more aggressive tumor category due to their size, invasiveness and response to treatment. Our objective was to evaluate clinical, biochemical, and imaging characteristics, therapeutic response, and long-term evolution (outcome) of a cohort of men with prolactinoma. Patients and Methods: multicenter retrospective study including 311 men with prolactinoma. Initial clinical parameters, therapeutic modalities, PRL normalization rate and gonadal recovery, as well as tumor reduction were analyzed. The results were expressed as median (min-max range). Results: 35 micro (Mi) and 276 macroadenomas (Ma) were found (199 invasive, 71 Giant ≥4 cm). The median age at diagnosis was 41 (13-84) and 40 y-old (15-73) for micro and macro respectively. The most frequent reasons for consultation were symptoms of hypogonadism in patients with Mi, while visual disturbances, headache, and incidental findings were seen in patients with Ma. Apoplexy as presentation was observed in two patients with Ma. Hypogonadotrophic hypogonadism was present in 90 % of patients in whole cohort. Median basal PRL was 144 in Mi and 1633 ng/ml in Ma. Treatment with cabergoline (CAB) was indicated in all but one patient with Ma who remitted after surgery. Normalization of PRL was achieved in 85.7% and 65.7% of Mi and Ma respectively. The median follow-up time was 48 months (6-240). Sixty-three Ma and only one Mi were submitted to surgery, 2 patients achieved remission criteria (Mi/Ma); a patient with micro experienced recurrence after 3 years, the remaining patients continued or started CAB after surgery. Ki-67 ≥3% was reported in 17/46 available pathologies. The maximum dose of CAB was 4.5 and 12 mg/wk , with a median of 0.5 and 1.5 mg/wk for Mi and Ma, respectively. Resistance to CAB (dose ≥3mg/week) occurred in 5.7% Mi and 35.4% Ma. Gonadal function recovery without testosterone requirement was achieved in 80% of Mi and 63% of Ma. Tumor remnant was observed in 34% and 49% of Mi and Ma respectively Ten patients with Ma received radiotherapy. Five patients presented CSF fistula during treatment with CAB, and another 3 impulse control disorder. One patient with carcinomatous transformation was treated with temozolomide. Conclusions: In our series of 311 men with prolactinomas, majority Ma consulted for neuro-ophthalmological symptoms, while hypogonadism was the most frequent initial symptom in Mi, despite the fact that 90% of the total population showed it at presentation. Giant, invasive and proliferative tumor were highly prevalent in Ma. Pharmacological treatment continues to be the first line of choice, with a high rate of normalization of PRL and recovery of gonadal function, but a low rate of long-term remission. Presentation: 6/2/2024