Practice patterns in children, adolescents, and young adults with mycosis fungoides: Single institution study.

Abstract

e19553 Background: Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma, but management remains heterogenous. MF management is based on disease stage, comorbidities, availability, and physician preference. Few studies have assessed treatment in children, adolescents, and young adults because prognosis in these groups is generally favorable; however, optimizing therapeutic protocols for these patients will improve clinical care and reduce adverse effect incidence. Here, we retrospectively describe the practice patterns and disease response for the child, adolescent, and young adult with MF. Methods: We retrospectively reviewed clinical data on 46 patients younger than 40 years with MF treated at Moffitt Cancer Center between 2009 and 2019. Mean time to next therapy (mTTNT) was used as a surrogate marker for the duration of clinical benefit. Group differences in mTTNT for patients with early-stage MF was assessed using Kaplan-Meier analysis. P-values were calculated using the log-rank test. Results: Overall, mean age was 29.2 years (range: 6.6-39.8). Topical steroids (47.8%) and narrowband-UVB (nbUVB) (19.6%) were the most utilized first line treatments regardless of disease stage. Forty patients had early-stage MF (stage IA-IIA). Among them, mean age was 27.8 years (6.6-36.6); 55% received topical steroids and 22.5% received nbUVB first line. These patients received a mean of three (1-7) unique therapies throughout their treatment course. Other reported topicals were retinoids, nitrogen mustard and pimecrolimus. Systemic retinoids were used in one early-stage case. Used first line in early-stage disease, topical therapy resulted in a mTTNT of 25 months ( p= 0.015); mTTNT after combination and systemic therapy was 12 and 5.5 months. As second line treatment, phototherapy resulted in a mTTNT of 58 months, but this finding was not statistically significant ( p= 0.11). Topical and systemic agents used second line resulted in mTTNT of 34 and 33 months. Six patients had advanced-stage MF (stage IIB-IVB) with a mean age of 27.6 years (19.9-35.8), two of which died from the disease. Each patient received a different first line therapy: topical nitrogen mustard, systemic steroids, systemic retinoids, radiation, psoralen and UVA light, or CHOP chemotherapy. Mean number of therapies administered to this cohort was five (2-9). Conclusions: In children, adolescents, and young adults with MF, topical and phototherapies were used more frequently than systemic therapies or radiation. In early-stage disease, the longest clinical response was achieved with topical treatments. Used second line, phototherapy demonstrated promising disease response trends compared to those of other modalities. Systemic therapy does not produce durable disease response in the first line setting; however, its utility in advanced-stage disease and as a second line agent requires further research.