Pembrolizumab Monotherapy for Recurrent or Metastatic Cutaneous Squamous Cell Carcinoma: A Single-Arm Phase II Trial (KEYNOTE-629)

PURPOSE

Treatment options are limited for patients with recurrent and/or metastatic (R/M) cutaneous squamous cell carcinoma (cSCC); mortality rates exceed 70% in patients with distant metastases. Here, we present the first interim analysis of the R/M cSCC cohort from the 2-cohort-locally advanced and R/M-phase II KEYNOTE-629 study.

PATIENTS AND METHODS

Patients with R/M cSCC not amenable to surgery or radiation received pembrolizumab 200 mg every 3 weeks. The primary end point was objective response rate per RECIST v1.1. Secondary end points were duration of response, disease control rate, progression-free survival, overall survival, and safety.

RESULTS

At data cutoff (April 8, 2019), median follow-up of 105 enrolled patients in the R/M cohort was 11.4 months (range, 0.4 to 16.3 months). Objective response rate was 34.3% (95% CI, 25.3% to 44.2%; 4 complete responses, 32 partial responses), and disease control rate was 52.4% (95% CI, 42.4% to 62.2%). Median duration of response was not reached (range, 2.7 to 13.1+ months; '+' refers to ongoing response at data cutoff). Median progression-free survival was 6.9 months (95% CI, 3.1 months to 8.5 months). Median overall survival was not reached (95% CI, 10.7 months to not reached). Treatment-related adverse events occurred in 66.7% of patients (n = 70), the most common of which were pruritus (n = 15; 14.3%), asthenia (n = 14; 13.3%), and fatigue (n = 13; 12.4%). Grade 3 to 5 treatment-related adverse events occurred in 5.7% (n = 6) of patients. One patient died of treatment-related cranial nerve neuropathy.

CONCLUSION

Pembrolizumab demonstrated effective antitumor activity; clinically meaningful, durable responses; and acceptable safety in primarily elderly patients with R/M cSCC, supporting its use in clinical practice. Pembrolizumab adverse events in this study were consistent with its established safety profile.

Phase II Study of Pembrolizumab As First-Line, Single-Drug Therapy for Patients With Unresectable Cutaneous Squamous Cell Carcinomas

PURPOSE

To evaluate first-line pembrolizumab monotherapy efficacy and safety in patients with unresectable cutaneous squamous cell carcinomas (CSCCs).

PATIENTS AND METHODS

Patients, predominantly men, with their CSSCs' immunohistochemically determined programmed cell death-ligand 1 (PD-L1) status determined (tumor proportion score threshold, 1%), received pembrolizumab (200 mg every 3 weeks). The primary endpoint was the 39-patient primary cohort's objective response rate at week 15 (ORR_W15). Secondary objectives were best ORR, overall survival (OS), progression-free survival (PFS), duration of response (DOR), safety, ORR according to PD-L1 status and health-related quality of life using Functional Assessment of Cancer Therapy-General (FACT-G) score. An 18-patient expansion cohort, recruited to power the study to evaluate the ORR_W15 difference between PD-L1+ and PD-L1- patients, was assessed for ORR, disease control rate, and safety, but not survival.

RESULTS

Median age of all patients was 79 years. The primary cohort's ORR_W15 was 41% (95% CI, 26% to 58%), including 13 partial and 3 complete responses. Best responses were 8 partial and 8 complete responses. At a median follow-up of 22.4 months, respective median PFS, DOR, and OS were 6.7 months, not reached, and 25.3 months, respectively. Pembrolizumab-related adverse events affected 71% of the patients, and 4 (7%) were grade ≥ 3. One death was related to rapid CSCC progression; another resulted from a fatal second aggressive head and neck squamous cell carcinoma diagnosed 15 weeks postinclusion. ORR_W15 for the entire population was 42%; it was significantly higher for PD-L1+ patients (55%) versus PD-L1- patients (17%; P = .02). Responders' W15 total FACT-G score had improved (P = .025) compared with nonresponders.

CONCLUSION

First-line pembrolizumab monotherapy exhibited promising anti-CSCC activity, with durable responses and manageable safety. PD-L1 positivity appears to be predictive of pembrolizumab efficacy.

European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 1: treatment delivery and established indications - actinic keratoses, Bowen's disease and basal cell carcinomas

Topical photodynamic therapy (PDT) is a widely approved therapy for actinic keratoses, Bowen's disease (squamous cell carcinoma in situ), superficial and certain thin basal cell carcinomas. Recurrence rates when standard treatment protocols are used are typically equivalent to existing therapies, although inferior to surgery for nodular basal cell carcinoma. PDT can be used both as lesional and field therapies and has the potential to delay/reduce the development of new lesions. A protocol using daylight to treat actinic keratoses is widely practised, with conventional PDT using a red light after typically a 3-h period of occlusion employed for other superficial skin cancer indications as well as for actinic keratoses when daylight therapy is not feasible. PDT is a well-tolerated therapy although discomfort associated with conventional protocol may require pain-reduction measures. PDT using daylight is associated with no or minimal pain and preferred by patient. There is an emerging literature on enhancing conventional PDT protocols or combined PDT with another treatment to increase response rates. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical PDT in dermatology, prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence.

Follow-Up of Patients With Complete Remission of Locally Advanced Basal Cell Carcinoma After Vismodegib Discontinuation: A Multicenter French Study of 116 Patients

PURPOSE

Vismodegib is a hedgehog pathway inhibitor indicated for the treatment of locally advanced basal cell carcinoma (laBCC), with an objective response rate of 65%, including a 32% complete response (CR). However, adverse effects often lead to drug discontinuation. The objective of our study was to evaluate long-term responses, predictive factors, and management of relapse after vismodegib discontinuation.

METHODS

An observational retrospective study was conducted in nine French oncodermatology units. We included patients with laBCC with CR on vismodegib who discontinued treatment between March 2012 and January 2016; we reviewed charts up to June 2016. The primary objective was to evaluate median relapse-free survival (RFS). Secondary objectives were risk factors associated with RFS, relapse, and death and treatment modalities after relapse and their efficacy.

RESULTS

One hundred sixteen patients with laBCC were included. The median RFS was 18.4 months (95% CI, 13.5 to 24.8 months). The RFS rate at 36 months was 35.4% (95% CI, 22.5% to 47.9%) for the total population and 40.0% (95% CI, 25.7% to 53.7%) for patients without Gorlin syndrome. LaBCC to the limbs and trunk was the only variable independently associated with a higher risk of relapse (hazard ratio, 2.77; 95% CI, 1.23 to 6.22; P = .019). Twenty-seven patients (50%) who experienced relapse during follow-up were retreated with vismodegib, with an objective response in 23 (objective response rate, 85%; CR rate, 37%; partial response rate, 48%) and eligibility for surgery in 24 (42%).

CONCLUSION

Long-term response after vismodegib discontinuation is frequent. Most patients who experience a relapse still respond to vismodegib rechallenge.

Stage IV cutaneous squamous cell carcinoma: treatment outcomes in a series of 42 patients

BACKGROUND

The prevalence and incidence of cutaneous squamous cell carcinoma (cSCC) are increasing due to the ageing of the population and sun exposure. Advanced cSCC forms (locally advanced and/or locoregional metastatic and/or distant metastatic) account for approximately 3% of cSCC and can result in death.

OBJECTIVE

Analysis of the clinical characteristics and treatment outcomes in stage IV cSCC with unresectable locoregional extension and/or the presence of metastases.

METHODS

A retrospective study was conducted at a single-centre university hospital for stage IV cSCC patients followed between 1 January 2008 and 31 December 2015. Descriptive analyses (demographic, anatomo-clinical characteristics, treatment sequences, response to treatment and survival analysis) were performed.

RESULTS

The study included 42 patients (median age = 75.5 years) with a diagnosis of stage IV cSCC who were treated with at least one line of chemotherapy and/or cetuximab. At the time of diagnosis, 85.7% of the patients had locoregional extension (19% of locally advanced and 67% of locoregional metastatic) and 14.3% had distant metastatic disease. Regarding treatment, 40% and 36% of patients received no more than 1 and 2 systemic treatment lines, respectively. The 4-year overall survival was 6%, and the median follow-up was 18.6 months. The objective response rate was 55% after the first line of treatment with a median progression-free survival (PFS) of 6.18 months and 12% after the second line with a median PFS of 6.51 months. Grade 3 and 4 adverse events were observed for 33% of patients.

CONCLUSION

Our study confirms a very poor prognosis of stage IV cSCC and a poor response to conventional therapies, indicating that the stage IV cSCC patient population remains with unmet medical needs.

Abstract CT170: KEYNOTE-629: Phase II study of pembrolizumab for recurrent/metastatic or locally advanced unresectable cutaneous squamous cell carcinoma

Background: Findings from Phase I and II clinical trials suggest that treatment with an anti-programmed death 1 (PD-1) antibody is well tolerated and provides durable antitumor activity in patients with local/regionally advanced or metastatic cutaneous squamous cell carcinoma (cSCC). Encouraging efficacy and safety findings have also been reported from an expansion cohort in the phase 1 KEYNOTE-012 trial with the PD-1 inhibitor pembrolizumab. KEYNOTE-012 demonstrated that pembrolizumab 200 mg administered once every 3 weeks was well tolerated and yielded a clinically meaningful overall response rate with evidence of durable responses in patients with recurrent and/or metastatic head and neck cSCC. To test the clinical activity of pembrolizumab, the open-label, single-arm, phase 2 KEYNOTE-629 trial (NCT03284424) will be carried out in patients with locally advanced, unresectable, and recurrent or metastatic cSCC.

Trial design: Patients will receive intravenous pembrolizumab 200 mg every 3 weeks for up to 35 infusions (≤24 months) or until protocol-specified treatment discontinuation. Treatment will not be stratified in this study. Eligibility criteria include age ≥18 years; locally advanced cSCC that is ineligible for surgical resection or radiotherapy (RT) or that previously underwent RT to the index site or systemic therapy for curative intent; presence of measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1; and Eastern Cooperative Oncology Group performance status 0 or 1. Treatment will be discontinued for progressive disease, unacceptable toxicity, intercurrent illness preventing study treatment administration, investigator’s decision, patient withdrawal of consent, pregnancy, or cessation for administrative reasons. Response will be assessed by computed tomography or magnetic resonance imaging 6 weeks after treatment initiation, every 6 weeks through year 1, then every 9 weeks thereafter or more frequently if clinically indicted. After a patient experiences disease progression or starts new anticancer therapy, the patient will be followed up and contacted every 12 weeks until death, consent withdrawal, or study end, whichever occurs first. Safety will be monitored throughout the study treatment and for 30 days after treatment end and for 90 days for serious adverse events after the end of treatment. The primary end point is objective response rate (RECIST v1.1). Secondary end points include duration of response, disease control rate, progression-free survival, overall survival, and safety. Recruitment is ongoing in 10 countries and will continue until approximately 50 additional patients with locally advanced unresectable cSCC are enrolled.

Citation Format: Jean-Jacques Grob, Rene Gonzalez Mendoza, Nicole Basset-Seguin, Jacob Schachter, Olga Vornicova, Jessica Bauman, Florent Grange, Nicolas Meyer, Josep Piulats, Pingye (Eric) Zhang, Burak Gumuscu, Ramona Swaby, Brett GM Hughes. KEYNOTE-629: Phase II study of pembrolizumab for recurrent/metastatic or locally advanced unresectable cutaneous squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT170.

Heterogeneity of PD-L1 expression and CD8 tumor-infiltrating lymphocytes among subtypes of cutaneous adnexal carcinomas

BACKGROUND

Adnexal carcinomas are rare and heterogeneous skin tumors, for which no standard treatments exist for locally advanced or metastatic tumors.

AIM OF THE STUDY

To evaluate the expression of PD-L1 and CD8 in adnexal carcinomas, and to study the association between PD-L1 expression, intra-tumoral T cell CD8+ infiltrate, and metastatic evolution.

MATERIALS AND METHODS

Eighty-three adnexal carcinomas were included. Immunohistochemistry using anti-PD-L1 monoclonal antibodies (E1L3N and 22C3) and CD8 was performed. PD-L1 expression in tumor and immune cells, and CD8+ tumor-infiltrating lymphocyte (TIL) density were analyzed semi-quantitatively.

RESULTS

Among the 60 sweat gland, 18 sebaceous and 5 trichoblastic carcinomas, 11% expressed PD-L1 in ≥ 1% tumor cells, more frequently sweat gland carcinomas (13%, 8/60) including apocrine carcinoma (40%, 2/5) and invasive extramammary Paget disease (57%, 4/7). Immune cells expressed significantly more PD-L1 than tumor cells (p < 0.01). Dense CD8+ TILs were present in 60% trichoblastic, 43% sweat gland, and 39% sebaceous carcinomas. CD8+ TILs were associated with PD-L1 expression by tumor cells (p < 0.01). Thirteen patients out of 47 developed metastases (27%) with a median follow-up of 30.5 months (range 7-36). Expression of PD-L1 by tumor cells was associated with the development of metastasis in univariate analysis (HR 4.0, 95% CI 1.1-15, p = 0.0377) but not in multivariate analysis (HR 4.1, 95% CI 0.6-29, p = 0.15).

CONCLUSION

PD-L1 expression is highly heterogeneous among adnexal carcinoma subtypes, higher in apocrine carcinoma and invasive extramammary Paget disease, and associated with CD8+ TILs. Our data suggest the interest of evaluating anti-PD1 immunotherapy in advanced or metastatic cutaneous adnexal carcinoma.