Ryan J. Brisson

Response-Adapted Volume De-escalation (RAVD) in Locally Advanced Head and Neck Cancer

BACKGROUND Efforts to reduce the late toxicity associated with chemoradiation (CRT) for locally advanced head and neck squamous cell cancer (LA-HNSCC) have focused on radiotherapy (RT) dose de-escalation. In this phase I/II protocol investigating the addition of everolimus to induction chemotherapy (IC), we incorporated a novel response-adapted volume de-escalation (RAVD) approach using IC response to guide the extent of RT volume reduction. PATIENTS AND METHODS Patients with measurable LA-HNSCC received two cycles of IC (cisplatin, paclitaxel, cetuximab ± everolimus). Patients with ≥50% reduction in the sum of tumor diameters [good response (GR)] received TFHX (paclitaxel, fluorouracil, hydroxyurea, and 1.5 Gy twice daily RT every other week) to a dose of 75 Gy with the single planning target volume (PTV1) encompassing exclusively gross disease. Patients with <50% response [non-response (NR)] were treated with TFHX encompassing PTV1 and the next nodal station at risk (PTV2) to a dose of 45 Gy followed by a sequential boost to PTV1 to a dose of 75 Gy. RESULTS Ninety-four patients were enrolled. Randomization to everolimus was discontinued on interim analysis after 50 patients due to futility. IC response was evaluable in 89 patients. Thirty-seven patients (41.6%) had GR and 52 (58.4%) had NR. There was a trend for improved progression-free (P = 0.086) but not overall survival (P = 0.94) for GR versus NR. The 2-year PFS and OS were 86.0% and 83.5% for GR and 68.7% and 85.4% for NR, respectively. NR were significantly more likely to undergo G-tube placement during treatment (50.0% GR versus 73.5% NR, P = 0.040) and be G-tube dependent at 6-month follow-up (5.7% GR versus 32.6% NR, P = 0.005). CONCLUSIONS The addition of everolimus to IC was not beneficial. The elimination of elective nodal coverage in patients with GR to IC did not appear to compromise outcomes and resulted in significantly decreased late toxicity. Further investigation of RAVD is warranted. CLINICALTRIALSGOV NCT01133678.

Characterization of the T-Cell Receptor Repertoire and Immune Microenvironment in Patients with Locoregionally Advanced Squamous Cell Carcinoma of the Head and Neck

Purpose: Squamous cell carcinoma of the head and neck (SCCHN) is a lethal cancer with a suboptimal 5-year overall survival of approximately 50% with surgery and/or definitive chemoradiotherapy. Novel treatments are thus urgently awaited. Immunotherapy with checkpoint blockade has emerged as a promising option for patients with recurrent/metastatic SCCHN; however, it has not been investigated in the curative-intent setting yet. The purpose of this study was to investigate the T-cell receptor repertoire and the tumor microenvironment in tumor tissues of SCCHN patients with locoregionally advanced disease. Experimental Design: We performed T-cell receptor sequencing of tumor tissues from 44 patients with locoregionally advanced SCCHN prior to treatment with definitive chemoradiotherapy and correlated the T-cell clonality and the mRNA expression levels of immune-related genes with clinicopathologic parameters. Results: Clonal expansion of T cells was significantly higher in human papilloma virus (HPV)–negative compared with HPV-positive tumors, signifying more robust antigen presentation in HPV-negative tumors. The latter was supported by the higher percentage of HPV-negative tumors expressing HLA-A protein compared with HPV-positive tumors (P = 0.049). Higher GRZB levels correlated significantly with longer recurrence-free survival (log-rank, P = 0.003) independent of tumor size, nodal stage, and HPV status. Conclusions: Our findings support clonal expansion of T cells in SCCHN patients with locoregionally advanced disease and imply differences in the antigen presentation capacity between HPV-negative and HPV-positive tumors. Elevated GRZB mRNA levels may also serve as a favorable and independent predictor of outcome in SCCHN patients treated with chemoradiotherapy. These data provide rationale for the introduction of immunotherapeutic approaches in the curative-intent setting. Clin Cancer Res; 23(16); 4897–907. ©2017 AACR.

Clinical and molecular features of innate and acquired resistance to anti-PD-1/PD-L1 therapy in lung cancer

Hypothesis The majority of non-small cell lung cancer (NSCLC) patients treated with anti-PD-1/PD-L1 therapy develop either innate or acquired resistance. Across tumor types, the “T cell-inflamed” tumor microenvironment correlates with clinical response to immunotherapy. We hypothesize that clinical characteristics may be predictive of resistance and that “T cell-inflamed” NSCLC tumors can be identified by gene expression profiling. Results Of 93 patients, 36 (38.7%) had innate resistance and 57 (61.3%) had initial benefit to immunotherapy. Innate resistance was associated with non-smokers (p = 0.013), more involved disease sites (p = 0.011), more prior therapy (p = 0.001), and a lower albumin level (p = 0.014). Among patients with initial benefit, factors associated with subsequent progression-free survival included higher Karnofsky Performance Status (KPS) (p = 0.004) and lower depth of response to anti-PD-1 therapy (p = 0.003). A “T cell-inflamed” microenvironment was identified in 42% of TCGA adenocarcinoma samples versus 21.0% of squamous cell. Discussion Specific clinical characteristics appear to be predictive of either innate or acquired resistance to anti-PD-1/PD-L1 therapy. A “T cell-inflamed” tumor was more common in adenocarcinoma than squamous histology. Methods A retrospective review of NSCLC patients treated with anti-PD-1/PD-L1 monotherapy. Patients with innate resistance to anti-PD-1/PD-L1 therapy (defined as progression at first CT evaluation) were compared to patients with initial clinical benefit. Among those with initial clinical benefit, we identified prognostic factors for time to progression (acquired resistance) or death. To further corroborate our findings on limited numbers, immune gene expression profiling of all NSCLC samples from the TCGA database was also pursued.

Definitive chemoradiation for locally-advanced oral cavity cancer: A 20-year experience

OBJECTIVES Definitive chemoradiation (CRT) for oral cavity squamous cell carcinoma (OC-SCC) is often criticized for poor efficacy or toxicity. We describe a favorable 20-year experience of primary CRT for locally-advanced OC-SCC. MATERIALS AND METHODS Patients with locally-advanced, stage III/IV OC-SCC receiving primary concomitant CRT on protocols from 1994 to 2014 were analyzed. Chemotherapy included fluorouracil and hydroxyurea with other third agents. Radiotherapy (RT) was delivered once or twice daily to a maximum dose of 70-75 Gy. Intensity-modulated RT (IMRT) was exclusively used after 2004. Progression-free survival (PFS), overall survival (OS), locoregional control (LRC), and distant control (DC) were calculated by the Kaplan-Meier method and compared across treatment decades using the log-rank test. Rates of osteoradionecrosis (ORN) requiring surgery were compared across treatment decades using the Chi-square test. RESULTS 140 patients with locally-advanced OC-SCC were treated with definitive CRT. Of these, 75.7% had T3/T4 disease, 68.6% had ≥N2 nodal disease, and 91.4% had stage IV disease. Most common primary sites were oral tongue (47.9%) and floor of mouth (24.3%). Median follow-up was 5.7 years. Five-year OS, PFS, LRC, and DC were 63.2%, 58.7%, 78.6%, and 87.2%, respectively. Rates of ORN and long-term feeding tube dependence were 20.7% and 10.0%, respectively. Differences in LRC (P = 0.90), DC (P = 0.24), PFS (P = 0.38), OS (P = 0.10), or ORN (P = 0.38) were not significant across treatment decades. CONCLUSION Definitive CRT is a viable and feasible strategy for organ preservation for patients with locally-advanced OC-SCC.

PS01.63: Clinical Characteristics of Acquired Resistance with Anti-PD-1/PD-L1 in Non–Small Cell Lung Cancer (NSCLC): Topic: Medical Oncology

Background: The development of programmed cell death 1 (PD-1)/PD-1 ligand 1 (PD-L1) checkpoint inhibitors has changed the landscape of nonesmall cell lung cancer (NSCLC) therapy, with 2 approvals from the US Food and Drug Administration of PD-1 inhibitors for second-line therapy. Information regarding relapse patterns, however is limited. This study investigates the the incidence, timeframe, and clinical features of acquired resistance to anti-PD-1/PD-L1 therapy. Methods: We collected retrospective data on 37 NSCLC patients treated at the University of Chicago Cancer Center from 2011-2016 with either Nivolumab or Pembrolizumab monotherapy. Acquired resistance was defined as patients who achieved initial partial or complete response (PR/CR) measured by RECIST v1.1 criteria followed by progression after initial response. Results: From this cohort, median age was 68.2, 22/37 (59%) had adenocarcinoma histology, and 18/37 (48%) were males. All patients had a prior smoking history (average of 40 pack years). 35 patients were treated with nivolumab, 2 patients with pembrolizumab. PR and SD were achieved in 14 (37.8%) and 9 (24.3%) of patients, respectively (overall clinical benefit rate was 62%). Median PFS was 6.3 months, while median OS was not reached. Best median RECIST change in tumor size for all PR and SD treated patients was 22.5%. Of the patients with SD or PR, 7/23 (30.4%) acquired resistance. For these patients, all had an ECOG score of 1-2 and 5/7 had received 2 lines of prior therapy. Five patients had squamous histology, two patients had adenocarcinoma. The two adenocarcinoma patients both had KRAS mutations (A146T and G12C). There was a 20.5% increase in tumor size from best median RECIST response. Median PFS was 6.30 months (1.3 months e 8.7 months). All patients had progression of existing lesions, rather than new lesions. Conclusion: We observed 30.4% of patients who initially had a clinical benefit develop resistance to antiPD-1/PD-L1 therapy with a median PFS of 6.3 months (1.3 months e 8.7 months). These occurred in patients with squamous histology or KRAS-mutant adenocarcinoma histology. In all cases, this was characterized by progression of prior lesions, rather than new lesions. Further studies are needed to fully characterize patterns of relapse and molecular characteristics of these patients.