Citations

11177 Background: Early detection of recurrence after curative-intent treatment is a critical priority, traditional imaging often detects relapse when disease burden is high, potentially limiting treatment efficacy. ctDNA has emerged as an established prognostic biomarker for molecular residual disease (MRD) detection and early relapse. We performed a real-world meta-analysis on published datasets that utilized personalized, tumor-informed ctDNA testing to assess its performance across tumor types and clinical management approaches. Methods: Real-world studies published from December 2022 to December 2025 using the personalized, tumor-informed Signatera ctDNA assay (Natera, Inc.) were included. Eligibility required ctDNA assessment in the MRD (2–16 weeks post-surgery (histology dependent)/pre adjuvant therapy (ACT)) and/or surveillance (post-ACT/end of the MRD window if no ACT was given) settings, with outcomes stratified by ctDNA status and hazard ratios (HR) reported from univariable or time-dependent Cox regression analysis. Exclusions included: clinical trials, biobanks, metastatic disease treated with palliative intent, case reports, reviews, editorials, or commentaries. Clinical outcomes were harmonized into a composite event-free survival (EFS) endpoint (time to recurrence, progression, or death). Pooled HRs and 95% CIs were estimated using random and fixed effects models and heterogeneity between studies was assessed using the I 2 and Cochran’s Q test. Median lead time from ctDNA-positivity to radiographic or clinical recurrence was summarized when available. Results: We identified 18 eligible publications comprising 3,004 unique patients across 15 solid tumor types. During the MRD window, ctDNA positivity was associated with a significantly increased risk of an EFS event compared with ctDNA negativity (pooled HR: 8.15; 95% CI: 6.12–10.85, I 2 = 0.00%, P = 0.844, n = 13). During the surveillance window, inclusive of post-definitive treatment, ctDNA positivity conferred an even greater EFS risk (pooled HR: 18.30; 95% CI: 14.17–23.65, I 2 = 0%, P = 0.911 for heterogeneity, n = 16). Across studies, ctDNA detection during surveillance preceded radiographic or clinical recurrence by a median of 3.20 months (95% CI: 2.50-4.10, P < 0.0001, n = 10), although this varied substantially by study/tumor type (I 2 = 80.9%). Conclusions: In this pan-cancer real-world meta-analysis, ctDNA positivity assessed using a tumor-informed assay was highly prognostic following curative-intent therapy at all timepoints evaluated with low heterogeneity between studies. These findings support the broad clinical utility of tumor-informed ctDNA testing for post-treatment risk stratification and longitudinal disease monitoring across solid tumors.

AbstractBackgroundA phase 2 cemiplimab study (NCT03132636) demonstrated a 24.1% objective response rate in patients diagnosed with metastatic basal cell carcinoma (mBCC) who were not candidates for continued hedgehog inhibitor (HHI) therapy due to intolerance to previous HHI therapy, disease progression while receiving HHI therapy, or having not better than stable disease on HHI therapy after 9 months. Here, health‐related quality of life (QoL) for this patient population is reported.MethodsAdult patients with mBCC were treated with intravenous cemiplimab at a dose of 350 mg every 3 weeks for 5 treatment cycles of 9 weeks/cycle then 4 treatment cycles of 12 weeks/cycle. Patients completed the European Organisation for Research and Treatment of Cancer Quality of Life‐Core 30 (QLQ‐C30) and Skindex‐16 questionnaires at baseline and Day 1 of each cycle. Across Cycles 2 to 9, the overall change from baseline was analyzed using a mixed model with repeated measures. Responder analyses determined clinically meaningful improvement or deterioration (changes ≥10 points) or maintenance across all scales.ResultsPatients reported low symptom burden and moderate‐to‐high functioning at baseline. Maintenance for QLQ‐C30 global health status (GHS)/QoL and across all functioning and symptom scales was indicated by overall mean changes from baseline. Clinically meaningful improvement or maintenance was reported at Cycle 2 for GHS/QoL (77%), functioning scales (77% to 86%), and symptom scales (70% to 93%), with similar proportions of improvement or maintenance at Cycles 6 and 9, excluding fatigue. On the Skindex‐16, clinically meaningful improvement or maintenance was reported across the emotional, symptom, and functional subscales, in 76%–88% of patients at Cycle 2, which were generally maintained at Cycles 6 and 9. Overall mean changes from baseline showed maintenance across these subscales.ConclusionsThe majority of patients treated with cemiplimab reported improvement or maintenance in GHS/QoL and functioning while maintaining a low symptom burden.

AbstractBackgroundMerkel cell carcinoma is a rare skin cancer associated with poor survival. Based on a previous Phase II trial of adults with advanced Merkel cell carcinoma by Kim and colleagues (2022), there is now a strong rationale for combination therapy (i.e., nivolumab and ipilimumab) to become a treatment option for patients with advanced Merkel cell carcinoma. The goal of this paper was to report on the secondary outcome of quality of life (QOL) among patients on this trial.MethodsPatients receiving combined nivolumab and ipilimumab, with or without stereotactic body radiation therapy (SBRT), completed the European Organisation for Research and Treatment of Cancer (EORTC) QLQ‐C30 prior to starting treatment and every 2 weeks thereafter. Changes in QOL during treatment and post‐treatment were evaluated using piecewise random‐effects mixed models. Exploratory analyses compared changes in QOL between study arms. The original trial was registered with ClinicalTrials.gov (NCT03071406).ResultsStudy participants (n = 50) reported no changes in overall QOL (ps > 0.05), but emotional functioning improved during treatment (p = 0.01). Cognitive and social functioning worsened post‐treatment (ps < 0.01). In general, patients treated with combination therapy only (n = 25) reported no change in QOL over time, whereas patients also treated with SBRT (n = 25) consistently demonstrated worsening QOL post‐treatment.ConclusionQOL is generally preserved in patients treated with combination therapy, but the addition of SBRT may worsen QOL. Combined with clinical efficacy data published previously, results support the use of combination therapy with nivolumab and ipilimumab as a treatment option for patients with advanced Merkel cell carcinoma.

Until recently, most patients with sentinel lymph node-positive (SLN+) melanoma underwent a completion lymph node dissection (CLND), as mandated in published trials of adjuvant systemic therapies. Following multicenter selective lymphadenectomy trial-II, most patients with SLN+ melanoma no longer undergo a CLND prior to adjuvant systemic therapy. A retrospective analysis of clinical outcomes in SLN+ melanoma patients treated with adjuvant systemic therapy after July 2017 was performed in 21 international cancer centers. Of 462 patients who received systemic adjuvant therapy, 326 patients received adjuvant anti-PD-1 without prior immediate (IM) CLND, while 60 underwent IM CLND. With median follow-up of 21 months, 24-month relapse-free survival (RFS) was 67% (95% CI 62% to 73%) in the 326 patients. When the patient subgroups who would have been eligible for the two adjuvant anti-PD-1 clinical trials mandating IM CLND were analyzed separately, 24-month RFS rates were 64%, very similar to the RFS rates from those studies. Of these no-CLND patients, those with SLN tumor deposit >1 mm, stage IIIC/D and ulcerated primary had worse RFS. Of the patients who relapsed on adjuvant anti-PD-1, those without IM CLND had a higher rate of relapse in the regional nodal basin than those with IM CLND (46% vs 11%). Therefore, 55% of patients who relapsed without prior CLND underwent surgery including therapeutic lymph node dissection (TLND), with 30% relapsing a second time; there was no difference in subsequent relapse between patients who received observation vs secondary adjuvant therapy. Despite the increased frequency of nodal relapses, adjuvant anti-PD-1 therapy may be as effective in SLN+ pts who forego IM CLND and salvage surgery with TLND at relapse may be a viable option for these patients.

Abstract Background: Cemiplimab is the first treatment approved in the US (as cemiplimab-rwlc) for patients with metastatic basal cell carcinoma (mBCC) or locally advanced disease (laBCC) after hedgehog inhibitor (HHI) treatment or for whom an HHI is not appropriate. Cemiplimab provided substantial clinical benefit and an acceptable safety profile in patients with laBCC who discontinued HHI therapy due to progressive disease (PD), intolerance, or no better than stable disease (SD) after 9 months (NCT03132636). Here, we present the primary analysis of the mBCC cohort. Methods: Patients with mBCC (nodal or distant) post-HHI treatment received cemiplimab 350 mg intravenously every 3 weeks for up to 93 weeks or until PD. The primary endpoint was objective response rate (ORR) by independent central review (ICR). Key secondary endpoints included safety and tolerability, ORR per investigator (INV) assessment, duration of response (DOR), progression-free survival (PFS), overall survival (OS), and complete response (CR) rate (data cutoff date: May 20, 2021). Results: Fifty-four patients were enrolled (70.4% male; median age 63.5 years [range, 38−90]; Eastern Cooperative Oncology Group performance status 0 [66.7%] and 1 [33.3%]). Median duration of follow-up was 8.4 months (range 1.5-36.2). ORR per ICR was 24.1% (95% confidence interval [CI], 13.5-37.6); with 1 CR and 12 partial responses (PRs). ORR per INV was 25.9% (95% CI, 15.0-39.7), with 2 CRs and 12 PRs. Among responders, median time to response per ICR was 4.0 months (range, 2.0−10.5). Estimated median DOR per ICR was 16.7 months (95% CI, 9.8-not evaluable). Disease control rate was 63.0% (95% CI, 48.7-75.7) per ICR and 70.4% (95% CI, 56.4-82.0) per INV. Median OS was not reached. Median PFS per ICR was 8.3 months (95% CI, 4.2-15.9). The most common treatment-related adverse events were fatigue (37.0%), diarrhea (14.8%), pruritus (13.0%), hyperthyroidism (9.3%), and arthralgia (9.3%) as well as hypothyroidism, asthenia, constipation, and maculo-papular rash (7.4% each). There were no treatment-related deaths. Conclusions: Cemiplimab provided clinically meaningful antitumor activity, including durable responses, and an acceptable safety profile in patients with mBCC who had progressed on or were intolerant to HHI therapy. Citation Format: Karl Lewis, Ketty Peris, Aleksander Sekulic, Alexander J. Stratigos, Lara Dunn, Zeynep Eroglu, Anne Lynn S. Chang, Michael R. Migden, Suk-Young Yoo, Kosalai Mohan, Ebony Coates, Emmanuel Okoye, Timothy Bowler, Jean-François Baurain, Oliver Bechter, Axel Hauschild, Marcus O. Butler, Leonel Hernandez-Aya, Lisa Licitra, Rogerio I. Neves, Emily S. Ruiz, Frank Seebach, David M. Weinreich, George D. Yancopoulos, Israel Lowy, Priscila Goncalves, Matthew G. Fury. Primary analysis of phase 2 results for cemiplimab in patients with metastatic basal cell carcinoma who progressed on or were intolerant to hedgehog inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT165.

9558 Background: Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by a dense fibrous stroma, resistance to chemotherapy and no actionable driver mutation for targeted therapy. We investigated the efficacy of PD-1/L1 inhibitors and correlation with genetic landscape and tumor immune microenvironment in DM. Methods: Retrospective analysis of 1054 pts with melanoma treated with anti-PD-1/L1, resulting in 57 pts with unresectable or metastatic DM. Available baseline biopsies were analysed by digital quantitative immunohistochemistry (IHC) for CD8 and PD-L1 and by whole exome sequencing (WES), compared to available tissue from non-DM pts treated with anti-PD1/L1 at UCLA. Results: At a median follow up of 20 mo, 40 pts (70%, 95% CI 57-82) had an objective response by RECIST 1.1 criteria, including 18 (45%) CRs with no relapse observed to date. Responses were similar in DM subsets (23 pure, 29 mixed and 5 indeterminate). Kaplan-Meier estimated 1-year and 2-year overall survival were 85% (95% CI 78-98) and 74% (95% CI 64-89). WES revealed a median of 1282 (interquartile range 517-1692) non-synonymous somatic mutations per tumor in DM tumors (n = 17), significantly higher (p = 0.02) than the median of 462 (interquartile range 230-1150) in non-DM (n = 23). Mutations in NF-1 were the most common (13/17) followed by loss-of-function TP53 and ARID2, and > 82% of single nucleotide mutations were UV damage signatures. IHC analysis from 19 DM and 13 non-DM revealed a strikingly higher percentage of PD-L1 positive cells in the tumor parenchyma in DM (p = 0.04), highly associated with CD8 density and PD-L1 expression in the tumor invasive margins, indicating an active adaptive immune response. No genetic mechanisms known to cause constitutive PD-L1 expression were detected in these samples. Conclusions: Patients with advanced DM derive significant clinical benefit from PD-1/L1 inhibitors, likely related to the high mutational burden and a highly active adaptive immune response as the main mechanism of immune escape prior to therapy. Our results challenge the general conception that dense fibrous stroma around the malignant cells interferes with immune cell infiltration and efficacy of immunotherapy.

9505 Background: D (BRAF inhibitor) + T (MEK inhibitor) combination therapy is associated with rapid clinical responses and has improved clinical outcomes in pts with BRAFV600–mutant MM, but long-term (˃ 3 y) clinical efficacy and safety data are limited. The longest follow-up to date of a randomized trial evaluating D+T at the approved dose (150 mg BID/2 mg QD [150/2]) was of the phase II study BRF113220 (part C; median, 45.6 mo) in which durable outcomes were achieved in some pts with BRAFV600–mutant MM (3-y OS, 38%). Here, we report updated 5-y landmark analyses to further characterize the impact of D+T in MM. Methods: Pts with BRAFV600–mutant mm enrolled in BRF113220 part C (NCT01072175) were randomized 1:1:1 to receive monotherapy D (150 mg BID), D+T (150 mg BID/1 mg QD), or D+T (150/2). Pts who progressed on D alone could cross over to the D+T 150/2 arm. Pt disposition, pt demographics, and 4- and 5-y efficacy and safety were analyzed for both the D-alone and D+T (approved 150/2 dose) arms. Results: This updated analysis represents an additional ≈ 2 y of follow-up (D and D+T arms; n = 54 each). As of 13 Oct 2016, 45 pts (83%) on D alone had crossed over to D+T. 20 pts were ongoing (D, n = 7 [13%]; D+T, n = 13 [24%]); 80% of D pts and 70% of D+T pts had died. D+T OS remained superior to D alone. The 4- and 5-y OS rates with D+T were 30% and 28%, respectively, demonstrating a stabilization of the OS curve. The PFS curve for D+T also remained stable (4- and 5-y: both 13%). Consistent with earlier results, the best OS for pts who received D+T was seen in pts with normal LDH (5-y, 45%) and normal LDH with disease in < 3 organ sites (5-y, 51%). At the 5-y landmark, 1 additional pt who received D+T improved from a partial to a complete response. Additional follow-up revealed no new safety signals with D+T. Detailed analyses of D crossover pts, responders, and post-progression therapy will be presented. Conclusions: This longest follow-up to date of BRAF + MEK inhibitor combination therapy in pts with BRAFV600–mutant mm revealed stable OS and PFS lasting ≥ 5 y with consistent tolerability. These results demonstrate that some pts with mm can achieve durable benefit with D+T therapy. Clinical trial information: NCT01072175.

Abstract Anti–PD-1 therapy has improved clinical outcomes in advanced melanoma, but most patients experience intrinsic resistance. Responding patients can develop acquired resistance to anti–PD-1. We retrospectively reviewed 488 patients treated with anti–PD-1 from three academic centers and identified 36 patients with acquired resistance, defined as disease progression following objective response. The incidence, timing, disease sites, post-progression survival (PPS), and outcomes were evaluated descriptively. The acquired resistance cohort consisted of 67% with more than 1 feature of poor prognosis (stage M1c, elevated LDH, or brain metastasis), and 67% had previously received ipilimumab. Partial and complete responses were achieved in 89% (n = 32) and 11% (n = 4) of patients, respectively, and median time to resistance (progression-free survival; PFS) was 11.1 months (range 4.3–32.8 months). Most progression was isolated (78% of patients, n = 28) and occurred while receiving therapy (78%, n = 28). The median PPS was 12.8 months (range 0.1–51.8 months), and the median overall survival was 33.7 months. Among isolated progressors, 15 received localized therapy (12 with surgery, 3 with radiation). Patients with isolated versus systemic progression exhibited a trend for improved PPS (P = 0.081), and patients with an initial PFS ≥ 15 months showed significant PPS improvement (P = 0.036). Two patients experienced subsequent responses to anti–PD-1 resumption. In conclusion, acquired resistance to anti–PD-1 was frequently associated with excellent clinical outcomes and often presented as isolated progression amenable to localized therapy (surgery or radiation) or systemic progression sensitive to therapy resumption. Cancer Immunol Res; 5(5); 357–62. ©2017 AACR.