1379. Idiopathic Granulomatous Mastitis: Experience at a Cancer Referral Center

Abstract Background Idiopathic granulomatous mastitis (IGM) is challenging as it a rare disease with unknown etiology, risk factors difficult to establish, and controversies regarding its treatment. Here we describe demographic clinical characteristics of patients IGM diagnosed at cancer referral center, well the microbial isolates Methods We reviewed charts IGM, from 2004 2019. Males were excluded. Demographic data, past medical history, signs symptoms, examination findings, radiological microbiological results, treatments retrieved. Frequencies calculated for qualitative variables measures central tendency dispersion quantitative variables. Association between categorical was explored logistic regression identify associated treatment response. Results Two hundred cases median age 38 years, reviewed. Concerning history 66 (33.8%) obese; 45 (30.4%) had used hormonal therapy; 6 (3.4%) an autoimmune disease; 158 (89.8%) been pregnant 100 (77.5%) breastfed. The most common skin induration (65%), delimited mass (64.5%), suppuration (52%). On imaging 53.8% suspicious malignancy. Culture performed on 88 (44%), 32 microorganism isolated, commonly Staphylococcus spp. (n=16; 51.6%) Corynebacterium (n=7; 22.6%). antibiotic regimen (n=84, 42%). Improvement noted first-line therapy in 92 (46%). Fourteen (7%) persistent symptoms 46 (23%), relapsed. presence fever (OR 11.94; CI95% 1.33-106.80; p=0.027) or 2.78; 1.25-6.19; p=0.012) poor Conclusion one largest series Latin America, population similar those other resource-limited countries. Fever greater failure initial isolation has also described series. variation therapeutic strategies opportunity standardize by means prospective studies. Disclosures All Authors: No reported disclosures.