Prompt response of advanced cutaneous squamous cell carcinoma to cemiplimab in a kidney transplant patient under everolimus treatment

Immune Checkpoint Inhibitors in Solid Organ Transplant Recipients With Advanced Skin Cancers-Emerging Strategies for Clinical Management

Use of immune checkpoint inhibitors (ICIs) in solid organ transplant recipients (SOTRs) with advanced skin cancers presents a significant clinical management dilemma. SOTRs and other immunosuppressed patients have been routinely excluded from ICI clinical trials with good reason: immune checkpoints play an important role in self- and allograft-tolerance and risk of acute allograft rejection reported in retrospective studies affects 10% to 65% of cases. These reports also confirm that cutaneous squamous cell carcinoma and melanoma respond to ICI therapy, although response rates are generally lower than those observed in immunocompetent populations. Prospective trials are now of critical importance in further establishing ICI efficacy and safety. However, based on current knowledge, we recommend that ICIs should be offered to kidney transplant recipients with advanced cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma if surgery and/or radiotherapy have failed. For kidney transplant recipients, this should be first line ahead of chemotherapy and targeted therapies. In SOTRs, the use of ICIs should be carefully considered with the benefits of ICIs versus risks of allograft rejection weighed up on a case-by-case basis as part of shared decision-making with patients. In all cases, parallel management of immunosuppression may be key to ICI responsiveness. We recommend maintaining immunosuppression before ICI initiation with a dual immunosuppressive regimen combining mammalian target of rapamycin inhibitors and either corticosteroids or calcineurin inhibitors. Such modification of immunosuppression must be considered in the context of allograft risk (both rejection and also its subsequent treatment) and risk of tumor progression. Ultimately, a multidisciplinary approach should underpin all clinical decision-making in this challenging scenario.

Systematic Review of Programmed Cell Death-1 Inhibitor Therapy for Advanced-Stage Cutaneous Squamous Cell Carcinoma in Solid-organ Transplant Recipients

BACKGROUND

Programmed cell death-1 (PD-1) inhibitors represent an effective treatment option for advanced cutaneous squamous cell carcinoma (cSCC). However, solid organ transplant (SOT) recipients with cSCC have traditionally been excluded from clinical trials.

OBJECTIVE

To assess the safety and efficacy of PD-1 inhibitors for stage III-IV cSCC in SOT recipients.

MATERIALS & METHODS

A systematic review was performed using the PubMed, EMBASE, and Scopus databases.

RESULTS

We identified 21 articles describing 33 SOT recipients (26 kidney, four liver, two lung, and one heart) with stage III-IV cSCC treated with PD-1 inhibitors. Eleven patients (33.3%) experienced allograft rejection. Of the 25 cases with iRECIST scores, twelve patients (48.0%) had a complete response (CR), eight (32.0%) showed a partial response (PR), three (12.0%) progressive disease, and two (8.0%) stable disease (SD). Including patients without available iRECIST scores, 21 patients (63.6%) showed tumor response. Eleven patients died, with six (50.0%) due to tumor progression and one (11.1%) due to allograft rejection after foregoing dialysis.

CONCLUSION

PD-1 inhibitors demonstrate efficacy for advanced cSCC and confer a risk of allograft rejection in SOT recipients, requiring careful assessment of risks and benefits. If anti-PD-1 therapy is pursued, use of mTOR inhibitors, prophylactic steroids, and donor-derived cell-free DNA monitoring may mitigate the risk of rejection.