Management of Lobular Granulomatous Mastitis; Special Focus on Treatment Challenges in Patients with Hyperprolactinemia, Erythema Nodosum, and Diabetes, and Factors Associated with a Persistent Disease Course

Abstract Background This study presents our observations on the management of patients with lobular granulomatous mastitis (LGM) in a cohort study. Additionally, characteristics associated with a longer disease course, as well as treatment challenges in patients with erythema nodosum, diabetes, and hyperprolactinemia would be discussed. Methods From 2015 to 2021, a total of 246 consecutive LGM patients referred to Ghaem teaching hospital, Mashhad, Iran, were treated and followed up every three months until complete symptom resolution. Treatment responses were categorized into five groups: complete resolution, incomplete resolution, resolution with subsequent relapse, no significant improvement, and treatment cessation. Telephone follow-ups were conducted with all patients at the end of the study in December 2022. The primary outcome was the response to treatment with prednisone or methotrexate (MTX). The secondary outcome was response to treatment by the last telephone follow-up. Results Among the initial 246 patients, 90 were excluded, and a total of 156 episodes were analyzed. Prednisone was administered to 136 patients, while oral MTX was prescribed to 48 cases. The median age of the cohort was 33 years (interquartile range [IQR], 29–38). The primary outcomes were as follows: Of those on prednisone, 57 (41.9%) achieved complete resolution, with 15 (11%) experiencing subsequent relapse, 33 (24.3%) showing no significant improvement, and 31 (19.9%) discontinuing treatment. Among the MTX recipients, 23 (47.9%) achieved complete resolution, while one showed incomplete resolution. The secondary outcomes were complete resolution in 139 (89.1%), incomplete resolution in nine (5.8%) showed, and 8 (5.1%) cases remained symptomatic. The median disease duration was 18 months (IQR, 7–36), with a median follow-up period of five years (IQR, 4–6). Abscess formation during treatment correlated with prolonged disease duration (p < 0.04), and higher plasma prolactin levels were associated with extended disease duration (p = 0.001). However, the disease course did not significantly differ in diabetic cases or those with erythema nodosum compared to others. Conclusions Over a median follow-up of five years, approximately 90% of LGM patients achieved complete resolution within a median course of 18 months. The presence of abscesses during treatment and elevated plasma prolactin levels were linked to longer disease duration.