Nontuberculous Mycobacterial Infections at a National Cancer Institute-Designated Comprehensive Cancer Center in Florida.

BACKGROUND: Nontuberculous mycobacteria (NTM) are environmental organisms that become opportunistic pathogens in certain populations. NTM prevalence has increased globally, likely due to increased diagnostic testing and the availability of population-based studies. Current literature on oncology patients is minimal and represents a unique study area. Here we present the epidemiology and treatment of NTM infection cases at a National Cancer Institute-designated comprehensive cancer center. METHODS: We performed a retrospective single-center cohort study of adults with microbiologically proven NTM infections presenting from 2020 to 2023. Epidemiologic and treatment-related data were retrieved from the electronic medical record and evaluated to illustrate institutional patterns. RESULTS: A total of 93 patients met assessment criteria, with most (74 of 93 [80%]) having a past or active cancer. Mycobacterium avium complex (47 of 93 [51%]) and Mycobacterium abscessus group (28 of 93 [30%]) were the most common isolates. The majority were pulmonary infections (75 of 93 [81%]), with the integument accounting for most extrapulmonary sites (14 of 18 [78%]). Of 93 patients, 49 (53%]) received therapy, with many (41 of 49 [84%]) receiving ≥3 agents. Thirty-nine (80%]) required an initial regimen modification, and 13 (27%) received dual β-lactam therapy (frequently including meropenem). Of treated patients, 36 (73%) demonstrated improved symptoms, 18 (37%) improved or partially improved radiologic change, and 19 (39%]) sustained culture conversion to negative at the evaluation time point; 13 (27%) died or were lost to follow-up. CONCLUSIONS: Our report offers one of the largest single-center epidemiologic perspectives on NTM infections in oncology patients. It offers unique insight into treatment practices in this population, particularly regarding dual β-lactam therapy.