Pembrolizumab and cabozantinib in recurrent and/or metastatic head and neck squamous cell carcinoma (RMHNSCC): long-term survival update with a biomarker analysis.

PURPOSE: Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent and/or metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKI) have immunomodulatory properties and improve clinical outcomes in combination with anti-PD-1 therapy. We report the long-term efficacy and safety of pembrolizumab and cabozantinib and include a correlative biomarker analysis. PATIENTS AND METHODS: This open-label, single-arm, multicenter, phase 2 study screened 50 patients with RMHNSCC, of whom 36 received pembrolizumab and cabozantinib. Primary endpoint was overall response rate (ORR), safety, and tolerability. Secondary endpoints included progression free survival (PFS), overall survival (OS), and correlative studies of tissue and blood. We report the long-term PFS, OS, safety, and describe correlative biomarkers. RESULTS: With median follow-up of 22.4 months, median PFS was 12.8 months 2-year PFS of 32.6% (95%CI 18.8-56.3%) and median OS of 27.7 months,2-year OS of 54.7% (95%CI 38.9-76.8%). Median duration of response was 12.6 months, with 2-year rate of 38.5% (95%CI 30.8-81.8%). Long-term TRAEs included manageable hypothyroidism (5.5%) and grade 1 elevated AST and ALT (2.8%). Baseline tumor p-MET expression correlated with ORR (p=0.0055). Higher density of CD8+, CD103+, and CSF1-R+ cells at baseline correlated with improved OS (hazard ratio [HR]=5.27, p=0.030; HR =8.79, p=0.017; HR =6.87, p=0.040, respectively). CONCLUSION: Pembrolizumab and cabozantinib provided prolonged encouraging long-term disease control and survival with a maintained favorable safety profile. The prognostic significance of increased CD8+, CD103+ and CSF1-R+ cell density in TIME deserve further evaluation in similar clinical settings.

Assessment of endpoint definitions in recurrent and metastatic mucosal head and neck squamous cell carcinoma trials: Head and Neck Cancer International Group consensus recommendations.

Transparent and precise endpoint definitions are a crucial aspect of clinical trial conduct and reporting, and are used to communicate the benefit of an intervention. Previous studies have identified inconsistencies in endpoint definitions across oncological clinical trials. Here, the Head and Neck Cancer International Group assessed endpoint definitions from phase 3 trials or trials considered practice-changing for patients with recurrent or metastatic mucosal head and neck squamous cell carcinoma, published between 2008 and 2021. We identify considerable and global heterogeneity in endpoint definitions, which undermines the interpretation of results and development of future studies. We show how fundamental components of even incontrovertible endpoints such as overall survival vary widely, highlighting an urgent need for increased rigour in reporting and harmonisation of endpoints.

Intensity-Modulated Reirradiation Therapy With Nivolumab in Recurrent or Second Primary Head and Neck Squamous Cell Carcinoma: A Nonrandomized Controlled Trial.

Importance: Intensity-modulated radiation therapy (IMRT) reirradiation of nonmetastatic recurrent or second primary head and neck squamous cell carcinoma (HNSCC) results in poor progression-free survival (PFS) and overall survival (OS). Objective: To investigate the tolerability, PFS, OS, and patient-reported outcomes with nivolumab (approved standard of care for patients with HNSCC) during and after IMRT reirradiation. Design, Setting, and Participants: In this multicenter nonrandomized phase 2 single-arm trial, the treatment outcomes of patients with recurrent or second primary HNSCC who satisfied recursive partitioning analysis class 1 and 2 definitions were evaluated. Between July 11, 2018, and August 12, 2021, 62 patients were consented and screened. Data were evaluated between June and December 2023. Intervention: Sixty- to 66-Gy IMRT in 30 to 33 daily fractions over 6 to 6.5 weeks with nivolumab, 240 mg, intravenously 2 weeks prior and every 2 weeks for 5 cycles during IMRT, then nivolumab, 480 mg, intravenously every 4 weeks for a total nivolumab duration of 52 weeks. Main Outcomes and Measures: The primary end point was PFS. Secondary end points included OS, incidence, and types of toxic effects, including long-term treatment-related toxic effects, patient-reported outcomes, and correlatives of tissue and blood biomarkers. Results: A total of 62 patients were screened, and 51 were evaluable (median [range] age was 62 [56-67] years; 42 [82%] were male; 6 [12%] had p16+ disease; 38 [75%] had salvage surgery; and 36 [71%.] had neck dissection). With a median follow-up of 24.5 months (95% CI, 19.0-25.0), the estimated 1-year PFS was 61.7% (95% CI, 49.2%-77.4%), rejecting the null hypothesis of 1-year PFS rate of less than 43.8% with 1-arm log-rank test P = .002 within a 1-year timeframe. The most common treatment-related grade 3 or higher adverse event (6 [12%]) was lymphopenia with 2 patients (4%) and 1 patient each (2%) exhibiting colitis, diarrhea, myositis, nausea, mucositis, and myasthenia gravis. Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Head and Neck Questionnaire quality of life scores remained stable and consistent across all time points. A hypothesis-generating trend favoring worsening PFS and OS in patients with an increase in blood PD1+, KI67+, and CD4+ T cells was observed. Conclusions and Relevance: This multicenter nonrandomized phase 2 trial of IMRT reirradiation therapy and nivolumab suggested a promising improvement in PFS over historical controls. The treatment was well tolerated and deserves further evaluation. Trial Registration: ClinicalTrials.gov Identifier: NCT03521570.

Assessing survival outcomes of patients with oral tongue squamous cell carcinoma: Focus on age, sex, and stage.

BACKGROUND: The purpose of this study was to provide further insights into whether age and/or sex are associated with prognosis in oral tongue squamous cell carcinoma. METHODS: This was a retrospective cohort study utilizing hospital registry data from 2006 to 2016 obtained from the National Cancer Database. Identified patients were divided into various cohorts based on age, sex, and staging. A descriptive analysis was performed using chi-square tests and overall survival rates were estimated using Kaplan-Meier method. RESULTS: A total of 17 642 patients were included in the study. The 5-year overall survival rates were 82.0% (95% CI: 79.8%-84.0%) in younger patients versus 67.5% (95% CI: 66.7%-68.3%, p-value <0.0001) older patients. The median overall survival for females was 143.4 months (95% CI: 133.2-NA) versus 129.8 (95% CI: 125.4-138.7, p-value <0.0001) in males. CONCLUSIONS: Our analysis suggests that younger age and female sex are both predictors of improved survival in oral tongue squamous cell carcinoma.

The evolving landscape of salivary gland tumors.

Salivary gland cancers are a rare, histologically diverse group of tumors. They range from indolent to aggressive and can cause significant morbidity and mortality. Surgical resection remains the mainstay of treatment, but radiation and systemic therapy are also critical parts of the care paradigm. Given the rarity and heterogeneity of these cancers, they are best managed in a multidisciplinary program. In this review, the authors highlight standards of care as well as exciting new research for salivary gland cancers that will strive for better patient outcomes.

Safety and efficacy of durvalumab after concurrent chemoradiation in Black patients with locally advanced non-small cell lung cancer.

BACKGROUND: The PACIFIC trial established consolidative durvalumab after concurrent chemoradiation as standard-of-care in patients with stage III or unresectable non-small cell lung cancer (NSCLC). Black patients, however, comprised just 2% (n = 14) of randomized patients in this trial, warranting real-world evaluation of the PACIFIC regimen in these patients. METHODS: This single-institution, multi-site study included 105 patients with unresectable stage II/III NSCLC treated with concurrent chemoradiation followed by durvalumab between 2017 and 2021. Overall survival (OS), progression-free survival (PFS), and grade ≥3 pneumonitis-free survival (PNFS) were compared between Black and non-Black patients using Kaplan-Meier and Cox regression analyses. RESULTS: A total of 105 patients with a median follow-up of 22.8 months (interquartile range, 11.3-37.3 months) were identified for analysis, including 57 Black (54.3%) and 48 (45.7%) non-Black patients. The mean radiation prescription dose was higher among Black patients (61.5 ± 2.9 Gy vs. 60.5 ± 1.9 Gy; p = .031), but other treatment characteristics were balanced between groups. The median OS (not-reached vs. 39.7 months; p = .379) and PFS (31.6 months vs. 19.3 months; p = .332) were not statistically different between groups. Eight (14.0%) Black patients discontinued durvalumab due to toxicity compared to 13 (27.1%) non-Black patients (p = .096). The grade ≥3 pneumonitis rate was similar between Black and non-Black patients (12.3% vs. 12.5%; p = .973), and there was no significant difference in time to grade ≥3 PNFS (p = .904). Three (5.3%) Black patients and one (2.1%) non-Black patient developed grade 5 pneumonitis. CONCLUSIONS: The efficacy and tolerability of consolidative durvalumab after chemoradiation appears to be comparable between Black and non-Black patients.

Patient-reported outcomes in immunotherapy for head and neck cancer.

BACKGROUND: Data about patient-reported outcomes (PROs) among patients with head and neck squamous cell carcinoma (HNSCC) treated with immune checkpoint inhibitors are sparse. Our exploratory study evaluated PROs in patients with HNSCC starting treatment with immune checkpoint inhibitor monotherapy or combination therapy with cetuximab. METHODS: Patients were recruited prior to receipt of their first checkpoint inhibitor therapy infusion. Participants completed measures of checkpoint inhibitor toxicities and quality of life (QOL) at on-treatment clinic visits. RESULTS: Among patients treated with checkpoint inhibitor monotherapy (n = 48) or combination therapy (n = 38) toxicity increased over time (p < 0.05), while overall QOL improved from baseline to 12 weeks, with stable or declining QOL thereafter (p < 0.05). There were no group differences in change in toxicity index or QOL. Toxicity index scores were significantly higher in the combination group at 18-20 weeks and 6 months post-initiation of immune checkpoint inhibitor (p < 0.05). There were no significant group differences at baseline, the 6-8 week (p = 0.13) or 3-month (p = 0.09) evaluations. The combination group reported better emotional well-being at baseline than the monotherapy group (p = 0.04), There were no other group differences QOL at baseline or later timepoints. CONCLUSIONS: Despite increasing patient-reported toxicity, checkpoint inhibitor monotherapy and combination therapy were associated with similar transient improvements, then worsening, of QOL in patients with HNSCC.

Pembrolizumab and cabozantinib in recurrent metastatic head and neck squamous cell carcinoma: a phase 2 trial.

Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor inhibitors, including tyrosine kinase inhibitors, have immunomodulatory properties and have offered promising results when combined with anti-PD-1 agents. We conducted a phase 2, multicenter, single-arm trial of pembrolizumab and cabozantinib in patients with RMHNSCC who had Response Evaluation Criteria in Solid Tumors v.1.1 measurable disease and no contraindications to either agent. We assessed the primary end points of tolerability and overall response rate to the combination with secondary end points of progression-free survival and overall survival and performed correlative studies with PDL-1 and combined positive score, CD8+ T cell infiltration and tumor mutational burden. A total of 50 patients were screened and 36 were enrolled with 33 evaluable for response. The primary end point was met, with 17 out of 33 patients having a partial response (52%) and 13 (39%) stable disease with an overall clinical benefit rate of 91%. Median and 1-year overall survival were 22.3 months (95% confidence interval (CI) = 11.7-32.9) and 68.4% (95% CI = 45.1%-83.5%), respectively. Median and 1-year progression-free survival were 14.6 months (95% CI = 8.2-19.6) and 54% (95% CI = 31.5%-72%), respectively. Grade 3 or higher treatment-related adverse events included increased aspartate aminotransferase (n = 2, 5.6%). In 16 patients (44.4%), the dose of cabozantinib was reduced to 20 mg daily. The overall response rate correlated positively with baseline CD8+ T cell infiltration. There was no observed correlation between tumor mutational burden and clinical outcome. Pembrolizumab and cabozantinib were well tolerated and showed promising clinical activity in patients with RMHNSCC. Further investigation of similar combinations are needed in RMHNSCC. The trial is registered at ClinicalTrials.gov under registration no. NCT03468218 .

Ninety-day mortality following transoral robotic surgery or radiation at Commission on Cancer-accredited facilities.

BACKGROUND: Postoperative mortality for oropharynx squamous cell carcinoma (OPSCC) with transoral robotic surgery (TORS) varies from 0.2% to 6.5% on trials; the real-world rate is unknown. METHODS: NCDB study from 2010 to 2017 for patients with cT1-2N0-2M0 OPSCC with Charleson-Deyo score 0-1. Ninety-day mortality assessed from start and end of treatment at Commission on Cancer-accredited facilities. RESULTS: 3639 patients were treated with TORS and 1937 with radiotherapy. TORS cohort had more women and higher income, was younger, more often treated at academic centers, and more likely to have private insurance (all p < 0.05). Ninety-day mortality was 1.3% with TORS and 0.7% or 1.4% from start or end of radiotherapy, respectively. From end of therapy, there was no significant difference on MVA between treatment modality. CONCLUSIONS: There is minimal difference between 90-day mortality in patients treated with TORS or radiotherapy for early-stage OPSCC. While overall rates are low, for patients with expectation of cure, work is needed to identify optimal treatment.

Specimen-Based Resection Margins and Local Control during Transoral Robotic Surgery for Oropharyngeal HPV-Mediated Squamous Cell Carcinoma.

OBJECTIVES: The aim of the study was to investigate the association of surgical margin conditions, including positive specimen margins revised to negative relative to local recurrence, disease-free survival, and overall survival (OS) within a cohort of HPV-mediated oropharyngeal squamous cell carcinoma (OPSCC) who underwent en bloc resection via transoral robotic surgery (TORS). MATERIALS AND METHODS: Retrospective cohort of patients with untreated HPV-mediated OPSCC cT1 or T2 undergoing TORS resection between October 2014 and March 2020. The methodologic description of our interdisciplinary institutional approach, number of cut-through margins (CTMs) during intraoperative consultation, percentage of final positive margin cases, and disease-free survival and OS stratified by margin status and margin tumor-free distance is identified. RESULTS: 135 patients with primary cT1/T2 HPV-mediated OPSCC met inclusion criteria. Twenty-eight of 135 (20.7%) specimens revealed CTM and were revised during the same operative setting. Three of 135 (2.2%) surgical cases had positive final margin status. Local control rate was 97%. On univariate analysis, margin distance did not impact OS. CTM and final positive margins had lower OS than initially negative margins (p = 0.044). Pathologic N-stage significantly impacted OS (p < 0.001). CONCLUSIONS: High local control rate and low final positive margin status confound the study of specimen margin-based techniques in HPV-mediated OPSCC resected en bloc with TORS. Pathologic N-stage may impact OS more than margin status. Larger numbers are needed to confirm differences.

Immune check point inhibitors in advanced cutaneous squamous cell carcinomas: "Repeat and replicate".

Recent evidence confirmed the significant clinical benefit from using immune check point inhibitors, namely PD-1 inhibitors, in patients with advanced cutaneous squamous cell carcinomas. The activity of these different agents seems to be strikingly equivalent. This phase 2 trial confirms a similar clinical benefit to single agent nivolumab in treating this disease. The replication of these findings raises the question of whether substitution of these immunotherapeutic agents can be justified based on smaller confirmatory trials.

Impact of radiation dose to the immune cells in unresectable or stage III non-small cell lung cancer in the durvalumab era.

BACKGROUND/PURPOSE: Higher estimated radiation doses to immune cells (EDIC) have correlated with worse overall survival (OS) in patients with locally-advanced non-small cell lung cancer (NSCLC) prior to the PACIFIC trial, which established consolidative durvalumab as standard-of-care. Here, we examine the prognostic impact of EDIC in the durvalumab era. MATERIALS/METHODS: This single-institution, multi-center study included patients with unresectable stage II/III NSCLC treated with chemoradiation followed by durvalumab. Associations between EDIC [analyzed continuously and categorically (≤6 Gy vs > 6 Gy)] and OS, progression-free survival (PFS), and locoregional control (LRC) were evaluated by Kaplan-Meier and Cox proportional methods. RESULTS: 100 patients were included with median follow-up of 23.7 months. The EDIC > 6 Gy group had a significantly greater percentage of stage IIIB/IIIC disease (76.0 % vs 32.6 %; p < 0.001) and larger tumor volumes (170 cc vs 42 cc; p < 0.001). There were no differences in early durvalumab discontinuation from toxicity (24.1 % vs 15.2 %; p = 0.27). Median OS was shorter among the EDIC > 6 Gy group (29.6 months vs not reached; p < 0.001). On multivariate analysis, EDIC > 6 Gy correlated with worse OS (HR: 4.15, 95 %CI: 1.52-11.33; p = 0.006), PFS (HR: 3.79; 95 %CI: 1.80-8.0; p < 0.001), and LRC (HR: 2.66, 95 %CI: 1.15-6.18; p = 0.023). Analyzed as a continuous variable, higher EDIC was associated with worse OS (HR: 1.34; 95 %CI: 1.16-1.57; p < 0.001), PFS (HR: 1.52; 95 %CI: 1.29-1.79; p < 0.001), and LRC (HR: 1.34, 95 %CI: 1.13-1.60; p = 0.007). CONCLUSIONS: In the immunotherapy era, EDIC is an independent predictor of OS and disease control in locally advanced NSCLC, warranting investigation into techniques to reduce dose to the immune compartment.

T cell repertoire in peripheral blood as a potential biomarker for predicting response to concurrent cetuximab and nivolumab in head and neck squamous cell carcinoma.

BACKGROUND: T cell receptor (TCR) signaling profile is a fundamental property that underpins both adaptive and innate immunity in the host. Despite its potential clinical relevance, the TCR repertoire in peripheral blood has not been thoroughly explored for its value as an immunotherapy efficacy biomarker in head and neck squamous cell carcinoma (HNSCC). The purpose of the present study is to characterize and compare the TCR repertoire in peripheral blood mononuclear cells (PBMC) from patients with HNSCC treated with the combination of cetuximab and nivolumab. METHODS: We used the immunoSEQ assay to sequence the TCR beta (TCR-B) chain repertoire from serially obtained PBMC at baseline and during the treatments from a total of 41 patients who received the combination (NCT03370276). Key TCR repertoire metrics, including diversity and clonality, were calculated and compared between patients with different therapy responses and clinical characteristics (eg, human papillomavirus (HPV) status and smoking history). Patient survival outcomes were compared according to patient groups stratified by the TCR-B clonotyping. To confirm the observed patterns in TCR spectrum, samples from patients who achieved complete response (CR) and partial response (PR) were further profiled with the immunoSEQ deep resolution assay. RESULTS: Our data indicated that the patients who achieved CR and PR had an increased TCR sequence diversity in their baseline samples, this tendency being more pronounced in HPV-negative patients or those with a smoking history. Notably, the CR/PR group had the lowest proportion of patients with oligoclonal TCR clones (2 out of 8 patients), followed by the stable disease group (9 out of 20 patients) and lastly the progressive disease group (7 out of 10 patients). An overall trend toward favorable patient survival was also observed in the polyclonal group. Finally, we reported the shared TCR clones across patients within the same response group, as well as the shared clones by aligning immunoSEQ reads with TCR data retrieved from The Cancer Genome Atlas- head and neck squamous cell carcinoma (TCGA-HNSC) cohort. CONCLUSIONS: Our data suggest that, despite the great clinical heterogeneity of HNSCC and the limited responders in the present cohort, the peripheral TCR repertoires from pretreatment PBMC may be developed as biomarkers for the benefit of immunotherapy in HNSCC.

A Multicenter Randomized Phase II Study of Single Agent Efficacy and Optimal Combination Sequence of Everolimus and Pasireotide LAR in Advanced Thyroid Cancer.

PURPOSE: Aberrant mTOR pathway and somatostatin receptor signaling are implicated in thyroid cancer and offer potential therapeutic targets. We assessed the clinical efficacy of everolimus and Pasireotide long-acting release (LAR) in radioiodine-refractory differentiated thyroid cancer (DTC) and medullary thyroid cancer (MTC). PATIENTS AND METHODS: Adults with progressive MTC and DTC untreated or treated with no more than one systemic agent were eligible. The trial was designed to establish the most promising regimen and the optimal combination sequence. Patients were randomized to start treatment with single agent everolimus (10 mg QD; Arm A), pasireotide-LAR (60 mg intramuscular injection, Q4 weeks; Arm B), or the combination (Arm C). At initial progression (PFS1), patients on Arm A or B switched to the combination and continued until progression (PFS2). Efficacy was measured by RECIST criteria. RESULTS: Study enrolled 42 patients: median age 65 years; female 17 (40.5%); White 31 (73.8%), African American 6 (14.3%), others 5 (11.9); DTC 32 (76.2%); MTC 10 (23.8%). There was no objective response by RECIST criteria across the three arms. Median and 1-year PFS1 rates were 8.3, 1.8, 8.1 months and 49.9%, 36.4%, 25.0% for Arms A, B, C, respectively. Median and 1-year PFS2 rates were 26.3, 17.5, 8.1 months and 78.4%, 70.0%, 25% for Arms A, B, C, respectively. The most frequent adverse events were anemia, stomatitis, fatigue, hyperglycemia, and hypercholesterolemia. CONCLUSIONS: The combination of everolimus and pasireotide-LAR showed promising efficacy over single agent. The delayed combination of everolimus and pasireotide-LAR following progression on single agent everolimus appeared intriguing as a combination strategy.

Phase II Multi-institutional Clinical Trial Result of Concurrent Cetuximab and Nivolumab in Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma.

PURPOSE: A phase II multi-institutional clinical trial was conducted to determine overall survival (OS) in patients with recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) treated with a combination of cetuximab and nivolumab. PATIENTS AND METHODS: Patients with R/M HNSCC were treated with cetuximab 500 mg/m2 i.v. on day 14 as a lead-in followed by cetuximab 500 mg/m2 i.v. and nivolumab 240 mg i.v. on day 1 and day 15 of each 28-day cycle. Expression of p16 and programmed cell death-ligand 1 (PD-L1) in archived tumors were determined. Tumor-tissue-modified human papillomavirus (TTMV) DNA was quantified in plasma. RESULTS: Ninety-five patients were enrolled, and 88 patients were evaluable for OS with a median follow-up of 15.9 months. Median OS in the 45 patients who had prior therapy for R/M HNSCC (cohort A) was 11.4 months, with a 1 year OS 50% [90% confidence interval (CI), 0.43-0.57]. Median OS in the 43 patients who had no prior therapy (cohort B) was 20.2 months, with a 1-year OS 66% (90% CI, 0.59-0.71). In the combined cohorts, the p16-negative immunostaining was associated with higher response rate (RR; P = 0.02) but did not impact survival while higher PD-L1 combined positive score was associated with higher RR (P = 0.03) and longer OS (log-rank P = 0.04). In the p16-positive patients, lower median (1,230 copies/mL) TTMV DNA counts were associated with higher RR (P = 0.01) and longer OS compared with higher median (log-rank P = 0.05). CONCLUSIONS: The combination of cetuximab and nivolumab is effective in patients with both previously treated and untreated R/M HNSCC and warrants further evaluation.

HPV as a Carcinomic Driver in Head and Neck Cancer: a De-escalated Future?

OPINION STATEMENT: Patients with HPV-associated oropharyngeal squamous cell carcinoma have improved prognosis relatively to those with tumors not driven by HPV. Both definitive radiotherapy (typically with concurrent chemotherapy) and transoral robotic surgery (with adjuvant therapies based on pathologic risk factors) are both acceptable treatment options for patients. The decision on which treatment is optimal depends on individual patient factors and should be made in a multi-disciplinary setting with input from a radiation oncologist, head and neck surgeon, and medical oncologist. Where appropriate, patients in this setting should be considered for enrollment on clinical studies evaluating de-escalation of treatment intensity given the very favorable outcomes and high toxicity profile associated with conventional therapies. However, caution is needed given negative data for de-escalation in the definitive chemotherapy and radiation setting. It remains unclear what the prognostic significance of HPV status is in patients with squamous cell carcinomas of the head and neck outside of the oropharynx.

Early response dynamics predict treatment failure in patients with recurrent and/or metastatic head and neck squamous cell carcinoma treated with cetuximab and nivolumab.

OBJECTIVES: Recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) is currently an incurable disease. To improve treatment strategies, combinations of cetuximab plus nivolumab or pembrolizumab were evaluated for efficacy and safety for incurable R/M HNSCC. While some patients had a significant clinical benefit with complete or partial response, most patients had stable or progressive disease (PD). To identify patients with a high likelihood of treatment failure and prevent futile treatments, we developed a mathematical model of early response dynamics as an early biomarker of treatment failure. MATERIALS AND METHODS: Demographics, RECIST assessment, and outcome were obtained from patients who were treated with combination of cetuximab and nivolumab on a previously published phase I/II clinical trial. We trained a tumor growth inhibition (TGI) ordinary differential equation (ODE) model describing patient-specific pre-treatment growth rate and uniform initial treatment sensitivity and rate of evolution of resistance. In a leave-one-out approach, we forecasted tumor burden and predicted time to progression (TTP) and PD. RESULTS: The TGI model accurately represented tumor burden dynamics (R2=0.98; RMSE=0.57 cm) and predicted PD with accuracy=0.71,sensitivity=1.00, and specificity=0.69 after three serial response assessment scans. Patient-specific pre-treatment growth rate correlated negatively with TTP (Spearman's ρ=-0.67,p=5.7e-05). CONCLUSION: The TGI model can identify patients with high likelihood of PD based on early dynamics. Further studies including prospective validation are warranted.

Efficacy and Safety of Patritumab Deruxtecan (HER3-DXd) in EGFR Inhibitor-Resistant, EGFR-Mutated Non-Small Cell Lung Cancer.

Receptor tyrosine-protein kinase ERBB3 (HER3) is expressed in most EGFR-mutated lung cancers but is not a known mechanism of resistance to EGFR inhibitors. HER3-DXd is an antibody-drug conjugate consisting of a HER3 antibody attached to a topoisomerase I inhibitor payload via a tetrapeptide-based cleavable linker. This phase I, dose escalation/expansion study included patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) with prior EGFR tyrosine kinase inhibitor (TKI) therapy. Among 57 patients receiving HER3-DXd 5.6 mg/kg intravenously once every 3 weeks, the confirmed objective response rate by blinded independent central review (Response Evaluation Criteria in Solid Tumors v1.1) was 39% [95% confidence interval (CI), 26.0-52.4], and median progression-free survival was 8.2 (95% CI, 4.4-8.3) months. Responses were observed in patients with known and unknown EGFR TKI resistance mechanisms. Clinical activity was observed across a broad range of HER3 membrane expression. The most common grade ≥3 treatment-emergent adverse events were hematologic toxicities. HER3-DXd has clinical activity in EGFR TKI-resistant cancers independent of resistance mechanisms, providing an approach to treat a broad range of drug-resistant cancers. SIGNIFICANCE: In metastatic EGFR-mutated NSCLC, after disease progression on EGFR TKI therapy, treatment approaches include genotype-directed therapy targeting a known resistance mechanism or chemotherapy. HER3-DXd demonstrated clinical activity spanning known and unknown EGFR TKI resistance mechanisms. HER3-DXd could present a future treatment option agnostic to the EGFR TKI resistance mechanism.See related commentary by Lim et al., p. 16.This article is highlighted in the In This Issue feature, p. 1.

The omission of intentional primary site radiation following transoral robotic surgery in 59 patients: No local-regional failures.

BACKGROUND: We assessed locoregional control with omission of intentional primary site radiation after transoral robotic surgery (TORS) and quantified nontargeted primary site dose. METHODS: Following Institutional Review Board (IRB) approval, patients treated with primary TORS resection for squamous cell carcinomas of the oropharynx were reviewed. Patients with cT1-2 tumors, >2 mm margins, in whom the surgeon resected the primary without revising specimen-driven margins, qualified for omission of primary site radiation. RESULTS: From 2014 to 2019, 112 patients met criteria. Fifty-nine (52%) patients did not receive radiation targeting the primary site; of whom, 22 received no radiation. In this group, there were no local failures; mean age was 58 years and median follow-up was 25 months. Thirty-seven patients received adjuvant radiation targeting the neck, mean bystander dose to the primary site was 28.8 Gy (range, 13.3-50.6 Gy). CONCLUSION: In a 59 patient population, omission of radiation to the primary site after TORS resulted in no locoregional failures.