Follicular T helper cells and cutaneous T-cell lymphomas

Abstract

In this issue of the BJD, Nikolaou et al. 3 report on a multicentre retrospective international cohort study designed to investigate clinical associations of skin toxicities induced by different ICI therapies. The study revealed that ICI-induced cutaneous toxicities may depend on certain factors, such as the specific agent used and the underlying type of malignancy.Although ICIs have been approved for numerous types of malignancies, the list of which is still expanding, it has been largely unclear whether different malignancies or different ICI agents lead to different skin toxicity profiles. In this study of 762 patients with cancer who developed cutaneous toxicities under ICI therapy, it was found that patients with macular rashes, vitiligo and multiple skin toxicities were treated more frequently for melanoma compared with nonsmall cell lung cancer (NSCLC). The study also noted that the use of anti-CTLA4 was less frequent than that of antiprogrammed death-1 in patients with macular rash and vitiligo. Moreover, the study revealed that the combination of ICI and chemotherapy may have a protective effect against some skin toxicities and high-grade (2 and 3) rashes compared with ICI monotherapy.In recent studies, macular rash has been frequently reported as the most common cutaneous irAE, 4,5 whereas many also reported bullous pemphigoid as a less common but more serious adverse event. 6,7 In the current study, psoriasis and pruritus were the most frequent toxicities reported, followed by macular rashes. Compared with other toxicities, macular eruptions developed after a lower number of doses (mean 4Á25 doses, P < 0Á001), whereas psoriasiform eruptions developed after a much greater number of doses (mean 8Á75, P < 0Á001). Also, pruritus was the most frequent skin toxicity in patients with renal cancer, while psoriasis was mainly reported in patients with NSCLC.This multicentre international study provides large-scale evidence that different malignancies may lead to different skin toxicity profiles. Also, the study reveals that cutaneous toxicities may vary depending on the specific ICI agent administered or a specific combination of therapy. While the aetiology and pathogenesis causing these differences need to be further elucidated, it is clear that there are multiple clinical factors to consider for patients with ICI-related cutaneous toxicities. As suggested by the authors, it would be prudent to have a multidisciplinary approach as standard care for these patients to ensure adequate and timely management of ICI-induced skin adverse events.