Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of nonmelanoma skin cancer

Abstract

Nonmelanoma skin cancers (NMSCs) are some of the most commonly diagnosed malignancies. In general, early-stage NMSCs have favorable outcomes; however, a small subset of patients develop resistant, advanced, or metastatic disease, or aggressive subtypes that are more challenging to treat successfully. Recently, immune checkpoint inhibitors (ICIs) have been approved by the US Food and Drug Administration (FDA) for the treatment of Merkel cell carcinoma (MCC), cutaneous squamous cell carcinoma (CSCC), and basal cell carcinoma (BCC). Although ICIs have demonstrated activity against NMSCs, the routine clinical use of these agents may be more challenging due to a number of factors including the lack of predictive biomarkers, the need to consider special patient populations, the management of toxicity, and the assessment of atypical responses. With the goal of improving patient care by providing expert guidance to the oncology community, the Society for Immunotherapy of Cancer (SITC) convened a multidisciplinary panel of experts to develop a clinical practice guideline (CPG). The expert panel drew on the published literature as well as their own clinical experience to develop recommendations for healthcare professionals on important aspects of immunotherapeutic treatment for NMSCs, including staging, biomarker testing, patient selection, therapy selection, post-treatment response evaluation and surveillance, and patient quality of life (QOL) considerations, among others. The evidence- and consensus-based recommendations in this CPG are intended to provide guidance to cancer care professionals treating patients with NMSCs.

Keywords: clinical trials as topic; guidelines as topic; immunotherapy; skin neoplasms.

Figure 1

FDA-approved ICI agents for NMSCs. Whenever possible, patients should be offered participation in clinical trials. Algorithm is intended to provide guidance and should not supplant sound clinical judgment—recommendations should be applied if feasible and as appropriate for individual patients. See product package inserts and the Approved anti-PD-(L)1 agents for MCC, Approved anti-PD-1 agents for CSCC, and Approved immunotherapy agents for BCC sections for more information on specific indications. *Some patients with advanced NMSC will be eligible for tissue-agnostic indications based on TMB and MSI/dMMR status. See the Tissue-agnostic indications for ICIs section for more information. †Advanced disease is defined in this guideline as tumors that are locally advanced, recurrent, and/or metastatic and not amenable to curative surgery or radiotherapy (box 1). ‡Or for whom an HHI is not appropriate. §Accelerated approvals contingent on confirmatory trials at the time of guideline publication. BCC, basal cell carcinoma; CSCC, cutaneous squamous cell carcinoma; dMMR, mismatch repair deficient; FDA, US Food and Drug Administration; HHI, hedgehog pathway inhibitor; ICI, immune checkpoint inhibitor; MCC, Merkel cell carcinoma; MSI, microsatellite instability; NMSC, nonmelanoma skin cancer; TMB, tumor mutational burden.