Unresectable Cutaneous Squamous Cell Carcinoma Research Articles

Durable tumor regression and restoration of neurologic function after treatment with anti-PD-1 in patients with functionally unresectable cutaneous squamous cell carcinoma with perineural spread into the cavernous sinus.

To describe tumor response and cranial nerve function outcomes after administration of anti-PD-1 to patients with cutaneous squamous cell carcinoma (CSCC) with perineural spread to cranial nerves (CN) extending into the cavernous sinus. Electronic patient records from a single institution were queried for patients with CSCC of the head and neck causing diplopia (ICD-10 H53.2) who were treated with anti-PD-1. Data extracted included demographics, duration of anti-PD-1 therapy, immune-mediated adverse reactions, tumor response per adapted RECIST v1.1, and changes in CN function and symptoms (e.g., pain). All patients were prescribed cemiplimab 350mg IV q3 weeks. Four patients met inclusion criteria. They had varying degrees of pain and sensory deficits in branches of the trigeminal nerve (CN V). One, 2, 3 and 1 patients had baseline involvement of CN III, IV, VI and VII, respectively. MRI confirmed perineural cavernous sinus involvement in all patients. Duration of anti-PD-1 therapy ranged 15-60weeks. All patients experienced an objective anti-tumor response to anti-PD-1; partial response n = 2, complete response n = 2. At a median follow-up of 22months, responses were ongoing in all patients. All patients demonstrated improvement in ocular motility deficits and pain with resolution of symptoms in 3 and 1 patients, respectively. Administration of anti-PD-1 to patients with CSCC with perineural spread into the cavernous sinus can generate durable anti-tumor regressions and restore CN function, while sparing the morbidity associated with surgical resection and/or radiotherapy. Our findings add to emerging literature supporting this treatment approach for this patient population.

Comparing PD-L1 scores for predicting pembrolizumab efficacy in first-line treatment of unresectable cutaneous squamous cell carcinomas.

e21593 Background: In the CARSKIN study (NCT02883556), 1L pembrolizumab demonstrated promising activity with durable responses and manageable safety in patients (pts) with unresectable locally advanced or metastatic CSCC. Here we report best ORR and survival endpoints of the entire cohort by PD-L1 status. Methods: The imaging assessment per RECIST v1.1 was blinded with independent central review. Best ORR, PFS, DOR OS, in the overall sample and by PD-L1 status was centrally assessed by 2 blinded independent pathologists, one using the anti–PD-L1 E1L3N clone (TPSE1L3N), the other using the 22C3 antibody (TPS22C3 and CPS22C3). Among 57 pts, 6 were excluded from the analysis: 2 untreated pts, 1 early unrelated death and 3 pts tested only with 1 assay). ROC curve analysis was used to compare assays. Results: With a median follow-up of 26 mo, best ORR was 51% with 14 PR (27%) and 12 CR (24%). Relapse occurred in 3 PR and 1 PD-L1 – CR pts. Respective median PFS, DOR, and OS were 13.7, NR, and 25.3 mo; respective 1-year PFS, DOR and OS were 50% [38-66], 80% [65-97] and 73% [61-86]. With a cutoff of 1%, best ORR was higher either for TPSE1L3N + pts vs TPSE1L3N – pts (60% vs 18%, p = 0.02) and for CPS22C3 + pts (59% vs 20%, p = 0.038), but not TPS22C3 + pts (p = 0.76). The optimal cutoff of CPS22C3 for ORR using a ROC curve was estimated to be ≥ 7% with a sensitivity of 0.70 and a specificity of 0.75. For best ORR, area under the ROC curve was higher for CPS22C3 (0.72) than TPSE1L3N (0.62) but the difference was not significant (P = 0.21). Pts with TPSE1L3N ≥ 1% had a higher 1-y PFS (57% vs 27%, p = 0.004) and OS (82% vs 42%, P = 0.01). Pts with CPS22C3 ≥ 1%, had a better 1-y OS (79% vs 50%, p = 0.03), but not 1y-PFS. Conclusions: CPS22C3 ≥ 7% appeared equivalent to TPSE1L3N ≥ 1% for predicting ORR and OS in pts receiving pembrolizumab in 1L treatment of advanced or metastatic CSCCs. Replications are warranted for validation. Pts with low scores might beneficiate from combined treatments. Clinical trial information: NCT02883556 .

Long-term outcomes of PD-1 blockade in metastatic or unresectable cutaneous squamous cell cancer.

e21551 Background: Cutaneous squamous cell carcinoma (CSCC) is the 2nd most common malignancy in the US. Approximately 10% of patients will experience either recurrent or metastatic disease, leading to worsened morbidity and mortality. In 2019, anti-PD1 therapy was FDA approved for metastatic or unresectable CSCC, and has been established as the standard frontline systemic therapy for this disease. Here we present our long-term, follow-up data investigating the efficacy, safety, and durability of PD-1 therapy for CSCC. Methods: This is a retrospective cohort study of metastatic or unresectable CSCC patients treated with PD-1 therapy at the University of Southern California Norris Comprehensive Cancer Center and the Scripps MD Anderson Cancer Center between June 2016 and January 2023. Patient demographics, tumor characteristics, and treatment related variables were collected. Objective response (ORR) was collected per RECIST criteria. Kaplan-Meier curves were used to estimate progression free survival (PFS) and overall survival (OS). For patients receiving salvage therapy post-PD1, progression free survival 2 (PFS2) and objective response rate 2 (ORR2) were also calculated. Toxicities were graded per CTCAE v5.0. Results: A total of 39 patients diagnosed with CSCC received at least one cycle of PD-1 therapy; among these 8 were excluded from efficacy analysis. Patients were on average 68 years old (range 22-97), predominantly male (69.2%) and Caucasian (74.4%). The most common primary tumor location was head/neck (64.1%), followed by extremity (15.4%). The mean tumor diameter was 6.0 cm (4.5-7.5, 95% CI). The majority of tumors were either moderately (33.3%) or poorly (28.2%) differentiated. The most common sites of metastatic disease included lymph node (41.0%), skin/soft tissue (33.3%) and bone (25.6%). Patients received on average 7 cycles of PD-1 therapy (range 1-26) and were followed for median 13.8 months. ORR for all patients was 39.0%, including CR and PR in 7 (22.6%) and 4 (13.0%) patients, respectively; 10 patients (32.2%) achieved stable disease (SD), while 7 patients (22.6%) had progression of disease (PD). Median PFS was 6.8 months, while OS was 26.7 months. Among 10 patients receiving salvage therapy after PD-1, 6 (60.0%) received a platinum-containing regimen. Median PFS2 was 4.4 months, while ORR2 was 10.0% with 1 PR, 4 SD, and 5 with PD. PD-1 therapy was well tolerated with 13 patients (33.3%) experiencing Grade 1-2 toxicity and 2 patients (5.2%) experiencing Grade 3-4. Conclusions: In this study of long-term outcomes of CSCC patients treated with PD-1 blockade, we found that initial responses to PD-1 therapy were durable, although PFS2 was less durable for patients who required salvage therapy and ORR2 was low. Novel treatment options are needed for patients with advanced CSCC who do not achieve durable responses to PD-1 based therapy.

A prospective study investigating the efficacy and toxicity of definitive ChemoRadiation and ImmunOtherapy (CRIO) in locally and/or regionally advanced unresectable cutaneous squamous cell carcinoma

BackgroundPatients with unresectable advanced cutaneous squamous cell carcinoma (cSCC) are generally treated with palliative intent. Immune checkpoint blockade has significant activity in the palliative setting in patients with recurrent or metastatic cSCC. This single arm phase 2 prospective study aims to investigate the combination of curative intent chemoradiation and durvalumab (anti-PD-L1 checkpoint inhibitor) for this patient cohort.MethodsPatients with unresectable locally and or regionally advanced pathologically confirmed cSCC (stage III-IVa) deemed fit for CRIO by consensus of the Multidisciplinary meeting will be eligible. In the first stage of a two-stage minimax design, we aim to recruit a total of 15 patients. If fewer than 7 patients achieved a complete response in the first stage, we will conclude the treatment is not more effective than standard treatment. The co-primary endpoints of CRIO are the safety of treatment (acute and late toxicities) and the rate of complete response. Secondary endpoints would include overall survival, progression free survival, and locoregional control. Translational research endpoints including biomarkers (CD73, CD39, PD-1, PD-L1) will also be explored utilising multiplex immunohistochemistry on tumour biopsy samples obtained prior to commencing treatment and during treatment (week 2). In addition, the utility of CXCR-4 PET/CT scan will be explored.DiscussionCRIO is a novel trial evaluating the combination of curative intent chemoradiotherapy with concurrent and adjuvant durvalumab for patients with unresectable stage III-IVa cSCC.Trial registration: Trial registered with the Australian New Zealand Clinical Trial Registry (ACTRN12618001573246)

FGFR Inhibition Overcomes Resistance to EGFR-targeted Therapy in Epithelial-like Cutaneous Carcinoma.

Recurrent and/or metastatic unresectable cutaneous squamous cell carcinomas (cSCCs) are treated with chemotherapy or radiotherapy, but have poor clinical responses. A limited response (up to 45% of cases) to EGFR-targeted therapies was observed in clinical trials with patients with advanced and metastatic cSCC. Here, we analyze the molecular traits underlying the response to EGFR inhibitors, and the mechanisms responsible for cSCC resistance to EGFR-targeted therapy. We generated primary cell cultures and patient cSCC-derived xenografts (cSCC-PDXs) that recapitulate the histopathologic and molecular features of patient tumors. Response to gefitinib treatment was tested and gefitinib-resistant (GefR) cSCC-PDXs were developed. RNA sequence analysis was performed in matched untreated and GefR cSCC-PDXs to determine the mechanisms driving gefitinib resistance. cSCCs conserving epithelial traits exhibited strong activation of EGFR signaling, which promoted tumor cell proliferation, in contrast to mesenchymal-like cSCCs. Gefitinib treatment strongly blocked epithelial-like cSCC-PDX growth in the absence of EGFR and RAS mutations, whereas tumors carrying the E545K PIK3CA-activating mutation were resistant to treatment. A subset of initially responding tumors acquired resistance after long-term treatment, which was induced by the bypass from EGFR to FGFR signaling to allow tumor cell proliferation and survival upon gefitinib treatment. Pharmacologic inhibition of FGFR signaling overcame resistance to EGFR inhibitor, even in PIK3CA-mutated tumors. EGFR-targeted therapy may be appropriate for treating many epithelial-like cSCCs without PIK3CA-activating mutations. Combined EGFR- and FGFR-targeted therapy may be used to treat cSCCs that show intrinsic or acquired resistance to EGFR inhibitors.

Increased PD-L1 Tumor Expression Correlates with High Rate of Response to PD-1 Inhibitors in Patients with Unresectable, Recurrent, and Metastatic Cutaneous Squamous Cell Carcinoma

Background: PD-1 inhibitors were approved for locally advanced and metastatic cutaneous squamous cell carcinoma (CSCC) in 2019 with ORR of 47% and CR of 4%. The identification of tumor characteristics that predict potential responders to immune checkpoint inhibitors (ICI) is an area of ongoing research. Here we present a series of consecutive patients with locally advanced unresectable, recurrent, or metastatic CSCC treated with PD-1 inhibitors and analyze tumor and blood genomics as well as PD-L1 expression with the aim to correlate with treatment response. Methods: We analyzed all cases of CSCC treated with single agent PD-1 inhibitors in the last 2 years at Wake Forest Comprehensive Cancer Center. Demographic and outcome data was collected. Tumors tested for genomics and PD-L1 expression in all cases with available tissue. PD-L1 tumor expression was tested by IHC utilizing DAKO 22C3 pharmDx antibodies. Tumor genomic studies including TMB and MSI were performed by Foundation Medicine platform. Blood was tested for circulating tumor DNA by Guardant 360 platform, at the beginning of treatment and in follow up at the time of maximum response. Response was assessed by RECIST 1.1 Criteria. Results (Table 1): Eleven patients with CSCC treated with PD-1 ICI were included in this study. Five patients had locally advanced disease, five patients had recurrent locally advanced disease, and three patients had metastatic disease. Three patients received treatment for at least 12 months and all have CR to date. Two patients have been on treatment for 6 months, and they have excellent PR with possible CR per imaging studies. Of the six patients who have been on treatment for less than 6 months, one patient has excellent PR with negative PET, three patients have very good clinical response with imaging studies pending, one patient has questionable response, and one patient only recently started treatment. Treatment is well tolerated with no treatment discontinuation. Immune-related complications are rare consisting of only one patient developing hypothyroidism during treatment. Eight patients had sufficient tumor tissue for genomic and PD-L1 testing. Initial blood genomic testing was performed in 10 of 11 patients and in follow up in all three patients who achieved maximum response. Patients with CR had PD-L1 of at least 30%. The additional tested patients have PD-L1 above 10%. The most frequently mutated tDNA gene was TP53 and the second most frequently mutated gene was the NOTCH1/2. TMB was intermediate or high in all tested patients. Discussion: Treatment of locally advanced unresectable, recurrent, and metastatic CSCC with ICI has led to a dramatic change in the management and prognosis of CSCC. Our series of patients with CSCC has a higher than reported rate of response and especially complete response. This corresponds with high TP53 alterations (100% of patients), NOTCH 1/2 alterations (90 % of patients) and high level of expression of PD-L1 (90% patients). Interestingly, PD-L1 rates were higher than previously published.

Efficacy and safety of panitumumab alone or in association with radiotherapy in unresectable cutaneous squamous cell carcinoma.

The prognosis of unresectable cutaneous squamous cell carcinomas is very poor. To evaluate the efficacy and safety of panitumumab alone or in association with radiotherapy in the treatment of unresectable cutaneous squamous cell carcinoma. This was a monocentre retrospective study of all consecutive patients having received at least two courses of panitumumab, alone or in association with radiotherapy, between 2016 and 2019. The primary endpoint was the rate of best overall response, evaluated according to the RECIST 1.1 criteria. The secondary endpoints were the response and disease control rates at 6weeks and 6months, progression-free survival, overall survival and safety. A total of 25 patients were included; their median age was 86years, and 17 (86%) had a WHO performance status over 2. The best overall response rate was 52%, including four complete responses (16%) and nine partial responses (36%). All patients with complete response and five out of nine patients with partial response had received concurrent radiotherapy, in most cases in moderate to low doses (<40 Gray, 67%). The response rates at 6weeks and 6months were 12% and 28%, respectively. The control rates at 6weeks and 6months were 84% and 32%, respectively. Median progression-free survival was 6.9months, and median overall survival was 10.5months. Grade 3 side-effects, mostly dermatological, occurred in 16 patients (64%). These results suggest that panitumumab remains pertinent in the treatment of unresectable cutaneous squamous cell carcinoma, in particular in association with radiotherapy, despite recent advances with anti-PD-1 antibodies. It presents several advantages: it can be used in very elderly or feeble patients, it does not provoke anaphylactic or other irreversible or life-threatening side-effects, and our study observed some long-term responses. Further prospective investigation of anti-EGFR antibodies, in association with anti-PD-1 antibodies and/or chemotherapy, should be conducted.

RF-Cemiplimab: First Drug Approved for the Treatment of Metastatic or Unresectable Cutaneous Squamous Cell Carcinoma

RF-Cemiplimab: First Drug Approved for the Treatment of Metastatic or Unresectable Cutaneous Squamous Cell Carcinoma

Cetuximab is efficient and safe in patients with advanced cutaneous squamous cell carcinoma: a retrospective, multicentre study

There is no standard of care for unresectable cutaneous squamous cell carcinoma (cSCC). Chemotherapy, alone or combined with radiotherapy, is commonly used mostly as palliative treatment; moreover, its poor safety profile limits its use most of the time, especially in elderly patients. Thus, alternative options are needed. Targeted molecular inhibitors, such as the epidermal growth factor receptor inhibitor cetuximab, seem promising, but data are limited. We retrospectively evaluated clinical outcomes of cetuximab as a single agent in this indication. The primary endpoint was the Disease Control Rate (DCR) at 6 weeks according to RECIST criteria. Secondary endpoints included DCR at 12 weeks, objective response rate (ORR) at 6 and 12 weeks, progression-free-survival (PFS), overall survival (OS), and safety profile. Fifty-eight patients received cetuximab as monotherapy. The median age was 83.2 (range, 47.4 to 96.1). The majority of patients was chemotherapy naïve. The median follow-up was 11.7 months (95% CI: 9.6-30.1). The DCR at 6 and 12 weeks was 87% and 70%, respectively. The ORR was 53% and 42%, respectively, at 6 and 12 weeks. The median PFS and OS were 9.7 months (95% CI: 4.8-43.4) and 17.5 months (95% CI: 9.4-43.1), respectively. Fifty-one patients (88%) experienced toxicity, and 67 adverse events related to cetuximab occurred. Most of them (84%) were grade 1 to 2. Our study shows that cetuximab is safe and efficient for the treatment of patients, even elderly ones, with advanced cSCC. These results indicate that cetuximab is a promising agent to test in new combinations, especially with immune checkpoint inhibitors such as anti–PD-1 agents.

Case Report: Cetuximab and nivolumab use in advanced cutaneous squamous cell carcinoma resistant to chemotherapy

We present the case of a 60-year-old man with unresectable cutaneous squamous cell carcinoma (cSCC) of the sternal area, which was not amenable to radiation therapy (stage III, T3N0M0). The treatment history of this patient is remarkable as the disease had progressed through all lines of conventional therapy established in the literature. The patient was treated with epidermal growth factor receptor (EGFR) inhibitor cetuximab for 35 cycles and restaged after 12 months of therapy with a whole body CT scan, documenting stage IV disease (T3N2bM1). The use of cetuximab as a single agent was effective for a limited time and we decided to initiate combination therapy with cetuximab and nivolumab. Restaging after six months of this combination regimen documented stable disease.

350P - Low-dose cisplatin and 5-fluorouracil combined concurrent chemoradiotherapy for unresectable cutaneous squamous cell carcinoma: Analysis of 23 cases

BackgroundCurrently, various chemotherapy regimens have been reported for the efficacy of unresectable squamous cell carcinoma (cSCC). However, there is no clear consensus. Here, we report the treatment results of unresectable cSCC in which concurrent chemoradiotherapy (CCRT) combining low-dose cisplatin and 5-fluorouracil (low-dose FP therapy) was performed in our department. MethodsA two-year retrospective study was conducted for 23 patients who had been received CCRT with low-dose FP therapy for unresectable cSCC. The patient age ranged from 44 to 79 years (mean age, 71 years), and gender was 17 men and 6 women. The primary lesions of unresectable cSCC were present in 7 cases in the head and neck, in 1 case in the upper limbs, in 5 cases in the lower limbs, and in 10 cases in the perineal region. Radiotherapy (RT) of CCRT had irradiated the primary lesion and regional lymph nodes. And for chemotherapy of CCRT, low-dose FP therapy was used. ResultsWhen 23 patients were classified by TNM staging (UICC 8th), stage 3 of unresectable cSCC was 5 patients (21.7%) and stage 4 was 18 patients (78.3%). 6 cases who those with stage 4 were dead (26.1%), while there were no dead cases who those with stage 3. Overall response rate (ORR) was 81 %, and median progression-free survival (PFS) was 392 days. For stage 4 of unresectable cSCC, one-year overall survival (OS) was 78 %, two-year OS was 56.7%, median survival time (MST) was 560 days. ConclusionsCCRT with low-dose FP therapy is an effective treatment for unresectable cSCC. However, tumors of the primary lesion and / or regional lymph nodes may remain after CCRT. In such cases, chemotherapy (i.e., maintenance therapy [MT]) should be continued after CCRT. In our department, most cases of unresectable cSCC receive MT after CCRT. Therefore, in the first treatment of unresectable cSCC, it is important how to make the tumor smaller. In this study, our cases had optimal results of ORR, median PFS, OS, and MST. According to these facts and results, we considered CCRT with low-dose FP therapy suppressed cSCC and is an effective treatment. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Continued Chemotherapy After Concurrent Chemoradiotherapy Improves Treatment Outcomes for Unresectable Cutaneous Squamous Cell Carcinoma: An Analysis of 13 Cases.

Background: There is no standard systemic therapy for unresectable cutaneous squamous cell carcinoma (ucSCC), although various chemotherapy regimens have been reported. In our department, concurrent chemoradiotherapy (CCRT) for ucSCC resulted in a 1-year survival rate similar to that of resectable cutaneous squamous cell carcinoma (cSCC). Treatment involves continued chemotherapy after CCRT. Here, we report the importance of continued chemotherapy after CCRT, based on treatment outcomes.Patients and Methods: We retrospectively evaluated 13 patients with ucSCC, assessing the overall survival, overall response rate (ORR), and disease control rate (DCR).Results: CCRT with continued chemotherapy resulted in an ORR of 84.6%, DCR of 92.3%, and 1-year survival rate of 75%. Of the 13 patients treated with CCRT with continued chemotherapy, 6 had no metastasis. The remaining 7 patients developed metastasis to other organs or lymph nodes beyond the regional lymph nodes, although most sites of metastasis were outside the irradiation area.Conclusion: We conclude that CCRT with continued chemotherapy was effective in treating the irradiation site (primary lesion and regional lymph nodes) and any organ metastasis, although, it is unclear for how long the treatment remains effective.

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

Abstract 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.

Case Report: Cetuximab use in advanced cutaneous squamous cell carcinoma resistant to chemotherapy

We present the case of a 60-year-old man with unresectable cutaneous squamous cell carcinoma (cSCC) of the sternal area, which was not amenable to radiation therapy. The treatment history of this patient is remarkable as the disease had progressed through all lines of conventional therapy established in the literature. We decided to initiate treatment with epidermal growth factor receptor (EGFR) inhibitor cetuximab and we reassessed the patient after 12 weeks with a whole-body CT scan, documenting stability in the size and radiologic features of the disease. Cetuximab, like all current treatments for advanced cSCC, is administered off-label and proved effective in preventing further progression of disease in our patient.

Pembrolizumab as first-line therapy in patients with unresectable cutaneous squamous cell carcinoma (cSCC): Phase 2 results from CARSKIN.

9547 Background: Cemiplimab, a PD-1-axis blocking agent, has recently been approved for unresectable cSCCs. We report results of the CARSKIN study evaluating pembrolizumab in the first-line setting. Methods: Chemotherapy naive patients (pts) with unresectable cSCCs, either locally or regionally advanced or metastatic, and ECOG PS ≤1 were accrued to this multi-institutional phase II trial to assess tumor response rate (RR) and safety of pembrolizumab administered IV (200 mg Q3W) for a period up to 24 months (mo). Baseline PD-L1 expression was centrally assessed on tumor. The primary endpoint was the RR at 15 weeks (wks) per RECIST v1.1 (independent review). A Simon two-stage design was used. Results: From 03/2017 to 01/2018, 39 pts (79% males, median age 79 years) were enrolled. Disease was local (18%), regional (62%) or metastatic (21%); 38% of pts were PS 0. The median number of infusions was 8. The median follow-up was 10.2 mo; 15 pts are still on pembrolizumab. Thirty-four pts were evaluable for tumor response, and 39 for toxicity. The RR at 15 wks was 38.5 % (95% CI: 24–55%) in the ITT population corresponding to 2 CR and 13 PR. The best responses were 3 CR and 12 PR. The DCR was 51% (20/39 including 5 SD) at 15 wks. The median PFS was 8.4 mo and the median OS was not reached. No responder has progressed to date including 2 pts who discontinued pembrolizumab for 6 to 12 mo. Treatment-related AEs (TRAEs) occurred in 67% of pts, including 8% with severe TRAEs (1 gr 3 cholestasis, 1 gr 3 colitis and 1 death due to recurrence of a non-related head and neck cancer) and 10% who discontinued because of a TRAE. Centrally assessed baseline PD-L1 expression was positive in 77% of patients (1% tumor staining threshold), but it failed to predict response at 15 wks with a median PD-L1 expression of 10% in responders and non-responders at 15 wks (P = .55). Conclusions: In this series of 39 elderly pts with unresectable cSCCs, the safety profile was consistent with previous pembrolizumab studies. First-line pembrolizumab provided robust antitumor activity regardless of PD-L1 expression levels. Clinical trial information: NCT02883556.

KEYNOTE-629: Phase 2 study of pembrolizumab for recurrent/metastatic or locally advanced unresectable cutaneous squamous cell carcinoma (cSCC).

TPS9598 Background: Findings from phase 1 and 2 studies suggest that targeting programmed death 1 (PD-1)/PD-L1 pathway can provide durable antitumor activity in patients with local/regionally advanced or metastatic cSCC and may be a promising treatment option. The open-label, single-arm, phase 2 KEYNOTE-629 trial (NCT03284424) will be conducted to test the clinical activity of the PD-1 inhibitor pembrolizumab in locally advanced, unresectable, and recurrent or metastatic cSCC. Methods: 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 for which the patient is ineligible for resection or radiotherapy (RT) or for which the patient 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 administration, investigator’s decision, patient withdrawal of consent, pregnancy, or cessation for administrative reasons. Response will be assessed by imaging 6 weeks after treatment initiation, every 6 weeks through year 1, and every 9 weeks thereafter or more frequently if clinically indicated. After disease progression or the start of new anticancer therapy, the patient will be followed up every 12 weeks until death, consent withdrawal, or study end, whichever occurs first. Safety will be monitored throughout the study and for 30 days after treatment end or 90 days if the patient experiences serious adverse events. The primary end point is objective response rate (RECIST v1.1). Secondary end points include response duration, 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. Clinical trial information: NCT03284424.

Isolated limb perfusion for unresectable extremity cutaneous squamous cell carcinoma; an effective limb saving strategy

Isolated limb perfusion for unresectable extremity cutaneous squamous cell carcinoma; an effective limb saving strategy

Emerging Nonsurgical Therapies for Locally Advanced and Metastatic Nonmelanoma Skin Cancer.

Locally advanced and metastatic nonmelanoma skin cancer (NMSC) not amenable to surgical resection requires a different approach to therapy. To review the efficacy and adverse effects of emerging treatment options for locally advanced and metastatic NMSC. A comprehensive search on PubMed was conducted to identify relevant literature investigating the role of program cell death 1 (PD-1) inhibitor, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitor, epidermal growth factor receptor (EGFR) inhibitor, and Hedgehog pathway inhibitors in the treatment of NMSC. PD-1 inhibitor and CTLA-4 inhibitor have shown promising efficacy with tolerable side-effect profiles in the treatment of NMSC, although the number of cases reported is limited. Currently, 3 larger-scale clinical trials are investigating PD-1 inhibitor therapy for NMSC. Similarly, EGFR inhibitor demonstrated marginal success in unresectable cutaneous squamous cell carcinomas. Hedgehog pathway inhibitors were approved by the US FDA for treatment of locally advanced and metastatic basal cell carcinomas and have shown favorable efficacy. Common adverse effects included muscle spasm, alopecia, and dysgeusia. Systemic therapies including PD-1 inhibitors and CTLA-4 inhibitors have demonstrated early promising results for difficult-to-treat NMSC. Future studies are necessary to optimize treatment outcome.

1293P - Cetuximab in patients with unresectable cutaneous squamous cell carcinoma is safe and effective: A real-life analysis

1293P - Cetuximab in patients with unresectable cutaneous squamous cell carcinoma is safe and effective: A real-life analysis

Isolated limb perfusion for unresectable extremity cutaneous squamous cell carcinoma; an effective limb saving strategy

BackgroundA small minority of patients present with locally advanced cutaneous Squamous Cell Carcinoma (cSCC). The aim of this study was to evaluate the effectiveness of Tumour necrosis factor α (TNF) and melphalan based isolated limb perfusion (TM-ILP) as a limb saving strategy for locally advanced extremity cSCC.MethodsA retrospective search from prospectively maintained databases, at two tertiary referral centers, was performed to identify patients treated with TM-ILP for locally advanced cSSC of an extremity between 2000 and 2015.ResultsA total of 30 patients treated with TM-ILP for cSCC were identified, with a median age of 71 years (36–92) and 50% female. Response could not be evaluated in 3 patients. After a median follow up of 25 months, the overall response rate was 81% (n = 22), with 16 patients having a complete response (CR, 59%). A total of 7 patients developed local recurrence, with a median time to recurrence of 9 months (Interquartile Range 7–10). Progressive disease was observed in 5 patients (19%). Limb salvage rate was 80%. The overall 2-year survival was 67%.ConclusionsTM-ILP should be considered as an option in patients with locally advanced cSCC in specialised centers, resulting in a high limb salvage rate.