FcyRIIB is a novel immune checkpoint in the tumor microenvironment limiting activity of Treg-targeting antibodies

Despite pre-clinical murine data supporting T regulatory (Treg) cell depletion as a major mechanism by which anti-CTLA-4 antibodies function in vivo, the two main antibodies tested in patients (ipilimumab and tremelimumab) have failed to demonstrate similar effects. We report analogous findings in an immunocompetent murine model humanized for CTLA-4 and Fcy receptors (hCTLA-4/hFcyR mice), where both ipilimumab and tremelimumab fail to show appreciable Treg depletion. Immune profiling of the tumor microenvironment (TME) in both mice and human samples revealed upregulation of the inhibitory Fcy receptor, FcyRIIB, which limits the ability of the antibody Fc fragment of human anti-CTLA-4 antibodies to induce effective antibody dependent cellular cytotoxicty/phagocytosis (ADCC/ADCP). Blocking FcyRIIB in humanized mice rescues Treg depleting capacity and anti-tumor activity of ipilimumab. For another target, CC motif chemokine receptor 8 (CCR8), which is selectively expressed on tumor infiltrating Tregs, we show that Fc engineering to enhance binding to activating Fc receptors, while limiting binding to the inhibitory Fc receptor, leads to consistent Treg depletion and single-agent activity across multiple tumor models, including B16, MC38 and MB49. These data reveal the importance of reducing engagement to the inhibitory Fc receptor to optimize Treg depletion by TME targeting antibodies. Our results define the inhibitory FcyRIIB receptor as a novel immune checkpoint limiting antibody-mediated Treg depletion in tumors, and demonstrate Fc variant engineering as a means to overcome this limitation and augment efficacy for a repertoire of antibodies currently in use or under clinical evaluation in oncology.

Chemoradiation therapy alters the PD-L1 score in locoregional recurrent squamous cell carcinomas of the head and neck

PD-L1 testing guides therapeutic decision-making for head and neck squamous cell carcinoma (HNSCC). We sought to understand whether chemoradiation therapy (CRT) influences the PD-L1 combined positive score (CPS) and other biomarkers of response to immunotherapy. PD-L1 expression was assessed using immunohistochemistry, and bulk RNA sequencing was performed on 146 HNSCC patients (65 primary sites, 50 paired local recurrences, and 31 paired regional recurrences). PD-L1 was scored using the CPS of ≥1, ≥20, and ≥50. Overall, 98 %, 54 %, and 17 % of HNSCCs had a CPS ≥1, ≥20, and ≥50, respectively. When using a cut-off of ≥1, CRT did not significantly change CPS at the locoregional recurrent site. However, there were significant changes when using CPS ≥20 or ≥50. The CPS changed for 32 % of patients when using a CPS ≥20 (p < 0.001). When using a CPS ≥50, there was a 20-23 % (p = 0.0058-0.00067) discordance rate at the site of locoregional recurrence. Oral cavity cancers had a significantly higher discordant rate than other primary sites for CPS ≥50, 44 % (8/18, p = 0.0058) and 58 % (7/12, p = 0.00067) discordance at the site of local and regional recurrence, respectively. When evaluating the 18 gene IFN-ɣ signature predictive of response to anti-PD-1 blockade, there was a statistically significant increase in the IFN-ɣ signature in recurrent larynx cancer (p = 0.02). Our study demonstrates that when using a higher cut-off of CPS ≥20 and ≥50, a repeat biopsy may be warranted after CRT for local and regional recurrent HNSCCs.

Moving beyond the T cell synapse for combination neoadjuvant immunotherapy in head and neck cancer

Patients with HPV-unrelated head and neck squamous cell carcinoma (HPV-unrelated HNSCC) show only modest benefit from treatment with PD-1 inhibitors (PD-1i). Targeting transforming growth factor β (TGF-β) may make PD-1i more effective by inducing T cell responses. In this issue of the JCI, Redman et al. performed a clinical trial in 14 patients with HPV-unrelated HNSCC using bintrafusp alfa, a bifunctional fusion protein that blocks PD-L1 and TGF-β. Primary tumors displayed pathologic responses with 5 of 14 patients having at least a partial response. While no primary tumor or metastatic lymph node demonstrated a complete pathologic response, the findings suggest that concurrent neoadjuvant inhibition of PD-L1 and TGF-β may provide a rational strategy to improve pathologic response and clinical outcome in patients with HPV-unrelated HNSCC.

Immunotherapy in head and neck squamous cell carcinoma: a narrative review

Objective:

Provide a narrative review of the literature describing immunological concepts and novel approaches in the treatment of head and neck squamous cell carcinoma.

Background:

In 2016, two anti-PD1 antibodies, nivolumab and pembrolizumab, were shown to improve overall survival in patients with recurrent/metastatic HNSCC and were approved by the US Food and Drug Administration (FDA) for use in the second line, cisplatin-resistant setting, although the overall response rates were only about 15%. More recently, pembrolizumab was approved for use in the first-line R/M setting as monotherapy in patients with CPS >1 or in combination with chemotherapy regardless of PD-L1 expression. Interestingly, while response rates with combination therapy were increased compared to pembrolizumab alone, the duration of response was shorter than might be expected. Based on a growing amount of evidence in other types of cancer treated with various combinations of immunotherapy, similar concepts are being studied in HNSCC, both in pre-clinical models and in clinical trials.

Methods:

A review of the literature was conducted using the Medline-PubMed and ClinicalTrials.gov databases. Main topics were selected for review, including basic immunology background, checkpoint inhibition, neoadjuvant immunotherapy, the combination of immunotherapy with radiation therapy and chemotherapy, intratumoral immunotherapy, and future prospects.

Conclusions:

There is an ongoing effort, which is supported by an increasing body of evidence, to enhance response rates with combinations of immunotherapy with other immunotherapy agents, targeted small molecules, chemotherapy, radiation therapy, and surgery. The clinician and the scientist should be familiarized with basic immunologic concepts, key findings in recent clinical trials, and current indications for administering immunotherapy.

Adjuvant and Neoadjuvant Therapies in Cutaneous Melanoma

Melanoma is the most common cause of skin cancer-related death in the United States. Cutaneous melanoma is most prevalent in the head and neck. The long-term prognosis has been poor and chemotherapy is not curative. Complete surgical resection with locally advanced disease can be challenging and melanoma is resistant to radiation. Advances made in immunotherapy and genomically targeted therapy have transformed the treatment of metastatic melanoma; as of 2021, the 5-year survival for metastatic melanoma is greater than 50%. Ongoing clinical studies are underway to integrate these life-saving therapies into the presurgical or postsurgical settings. This article reviews that effort.

Phase II Randomized Trial of Transoral Surgery and Low-Dose Intensity Modulated Radiation Therapy in Resectable p16+ Locally Advanced Oropharynx Cancer: An ECOG-ACRIN Cancer Research Group Trial (E3311)

PURPOSE

Definitive or postoperative chemoradiation (CRT) is curative for human papillomavirus-associated (HPV+) oropharynx cancer (OPC) but induces significant toxicity. As a deintensification strategy, we studied primary transoral surgery (TOS) and reduced postoperative radiation therapy (RT) in intermediate-risk HPV+ OPC.

METHODS

E3311 is a phase II randomized trial of reduced- or standard-dose postoperative RT for resected stage III-IVa (American Joint Committee on Cancer-seventh edition) HPV+ OPC, determined by pathologic parameters. Primary goals were feasibility of prospective multi-institutional study of TOS for HPV+ OPC, and oncologic efficacy (2-year progression-free survival) of TOS and adjuvant therapy in intermediate-risk patients after resection. TOS plus 50 Gy was considered promising if the lower limit of the exact 90% binomial confidence intervals exceeded 85%. Quality of life and swallowing were measured by functional assessment of cancer therapy-head and neck and MD Anderson Dysphagia Index.

RESULTS

Credentialed surgeons performed TOS for 495 patients. Eligible and treated patients were assigned as follows: arm A (low risk, n = 38) enrolled 11%, intermediate risk arms B (50 Gy, n = 100) or C (60 Gy, n = 108) randomly allocated 58%, and arm D (high risk, n = 113) enrolled 31%. With a median 35.2-month follow-up for 359 evaluable (eligible and treated) patients, 2-year progression-free survival Kaplan-Meier estimate is 96.9% (90% CI, 91.9 to 100) for arm A (observation), 94.9% (90% CI, 91.3 to 98.6]) for arm B (50 Gy), 96.0% (90% CI, 92.8 to 99.3) for arm C (60 Gy), and 90.7% (90% CI, 86.2 to 95.4) for arm D (66 Gy plus weekly cisplatin). Treatment arm distribution and oncologic outcome for ineligible or step 2 untreated patients (n = 136) mirrored the 359 evaluable patients. Exploratory comparison of functional assessment of cancer therapy-head and neck total scores between arms B and C is presented.

CONCLUSION

Primary TOS and reduced postoperative RT result in outstanding oncologic outcome and favorable functional outcomes in intermediate-risk HPV+ OPC.

Cancer case trends following the onset of the COVID-19 pandemic: A community-based observational study with extended follow-up

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has impacted health care delivery worldwide. Cancer is a leading cause of death, and the impact of the pandemic on cancer diagnoses is an important public health concern.

METHODS

This cross-sectional study retrospectively analyzed the electronic medical records of 80,138 cancer patients diagnosed between January 1, 2019, and May 31, 2021. Outcome measures included weekly number of new cancer cases and trends in weekly cancer cases, before and after the pandemic; patient demographics; and positive COVID-19 test rates.

RESULTS

Beginning March 4, 2020, defined as the onset of the pandemic, weekly cancer cases declined precipitously (-110.0 cases per week [95% confidence interval, -190.2 to -29.8]) for 4 weeks, followed by a moderate recovery (+23.7 cases per week [9.1 to 38.4]) of 10 weeks duration. Thereafter, weekly cancer cases trended slowly back toward pre-COVID-19 baseline levels. Following the pandemic onset, there was a cumulative year-over-year decline in cancer cases overall of 7.3%, including a 20.2%, 14.3%, and 12.8% decline in nonmelanoma skin cancer, breast cancer, and prostate cancer, respectively. Changes in case volumes were accompanied by variations in patient characteristics, including region, age, gender, race, insurance coverage, and COVID-19 positive test rates (P < .01 for all). Among patients tested for COVID-19, 5.3% had a positive result.

CONCLUSIONS

The data in this study demonstrate a substantial reduction in cancer diagnoses following the onset of COVID-19, which appear to reach expected pre-COVID norms 12 months later. The largest reduction was noted among cancers that are typically screen-detected or identified as part of a routine wellness examination.

A "Custom" Plate in a Day-Accurate Predictive Hole Fabrication Using Point-of-Care 3-Dimensional Printing

PURPOSE

In computer surgical planned (CSP) fibular reconstructions of the mandible, custom plates facilitate accurate and efficient transfer of the digital plan intraoperatively by a way of predrilled fixation holes. Stock plates are more easily accessible and are more economical but typically preclude the utilization of these predictive holes. The purpose of this article is to describe an accurate and economical alternative to custom plates, while still having the ability to create predictive holes for plate alignment and execution of a digital surgical plan.

METHODS

An in vitro accuracy study was performed on a point-of-care resin-printed predictive hole guide termed "prebent plate analog" (PPA). Twenty stock 2.0 reconstruction plates prebent against a 3-dimensional printed mandibular model reconstructed with a 2-piece fibula were used to fabricate 20 PPAs. The proximal and distal 4 holes of each prebent plate and corresponding PPA were assessed using a heat map overlay, measuring difference in millimeters between matching points of the predictive hole segments. The median distance from the points of reference in the PPA versus the prebent plate was calculated for each predictive hole position in addition to the average error of the PPA to the stock plate.

RESULTS

Eighteen PPAs were used for statistical analysis; 2 were damaged in transport. The mean error between the body (-0.265) and condylar segments (-0.116 mm) and mean difference in error between the proximal predictive holes (-0.124 mm) and distal predictive holes (-0.215 mm) on the PPA were not statistically different (P = .061, P = .314 general estimating equation regression, respectively). The mean error across the PPA predictive holes and corresponding holes of the prebent plates was -0.194 mm (P < .001, general estimating equation regression).

CONCLUSIONS

The PPA is a precise and accurate analog that faithfully replicates the position of proximal and distal components of a prebent stock plate, thereby allowing for predictive hole placement in lieu of a custom plate in fibula mandibular reconstruction cases.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

A platform for locoregional T-cell immunotherapy to control HNSCC recurrence following tumor resection

Surgical resection of head and neck squamous-cell carcinoma (HNSCC) is associated with high rates of local and distant recurrence, partially mitigated by adjuvant therapy. A pre-existing immune response in the patient's tumor is associated with better outcomes following treatment with conventional therapies, but improved options are needed for patients with poor anti-tumor immunity. We hypothesized that local delivery of tumor antigen-specific T-cells into the resection cavity following surgery would direct T-cells to residual antigens in the margins and draining lymphatics and present a platform for T-cell-targeted immunotherapy. We loaded T-cells into a biomaterial that conformed to the resection cavity and demonstrated that it could release T-cells that retained their functional activity in-vitro, and in a HNSCC model in-vivo. Locally delivered T-cells loaded in a biomaterial were equivalent in control of established tumors to intravenous adoptive T-cell transfer, and resulted in the systemic circulation of tumor antigen-specific T-cells as well as local accumulation in the tumor. We demonstrate that adjuvant therapy with anti-PD1 following surgical resection was ineffective unless combined with local delivery of T-cells. These data demonstrate that local delivery of tumor-specific T-cells is an efficient option to convert tumors that are unresponsive to checkpoint inhibitors to permit tumor cures.

Neoadjuvant immunotherapy is reshaping cancer management across multiple tumour types: The future is now!

The Italian Network for Tumor Biotherapy (Network Italiano per la Bioterapia dei Tumori [NIBIT]) Foundation hosted its annual 2020 Think Tank meeting virtually, at which representatives from academic, clinical, industry, philanthropic, and regulatory organisations discussed the role of neoadjuvant immunotherapy for the treatment of cancer. Although the number of neoadjuvant immunotherapeutic trials is increasing across all malignancies, the Think Tank focused its discussion on the status of neoadjuvant trials in cutaneous melanoma (CM), muscle-invasive urothelial bladder cancer (MIBC), head and neck squamous cell carcinoma (HNSCC), and pancreatic adenocarcinoma (PDAC). Neoadjuvant developments in CM are nothing short of trailblazing. Pathologic Complete Response (pCR), pathologic near Complete Response, and partial Pathologic Responses reduce 90-100% of recurrences. This is in sharp contrast to targeted therapies in neoadjuvant CM trials, where only a pCR seems to reduce recurrence. The pCR rate after neoadjuvant immunotherapy varies among the different malignancies of CM, MIBC, HNSCC, and PDAC and may be associated with different reductions of recurrence rates. In CM, emerging evidence suggests that neoadjuvant immunotherapy with anti-CTLA-4 plus anti-PD1 is a game changer in patients with palpable nodal Stage III or resectable Stage IV disease by curing more patients, reducing recurrences and the need for surgical interventions, such as lymph node dissections and metastasectomies. The Think Tank panel discussed future approaches on how to optimise results across different tumour types. Future approaches should include reducing monocyte-mediated (tumour-associated macrophages) and fibroblast-mediated (cancer-associated fibroblasts) barriers in the tumour microenvironment to facilitate the recruitment of immune cells to the tumour site, to reduce immune-suppressive mediators, and to increase antigen presentation at the site of the tumour.

Neoadjuvant immunoradiotherapy results in high rate of complete pathological response and clinical to pathological downstaging in locally advanced head and neck squamous cell carcinoma

BACKGROUND

Checkpoint inhibitors targeting programmed death receptor-1 (PD-1) have been tested in the neoadjuvant setting for the treatment of locoregionally advanced head and neck squamous cell carcinoma (HNSCC); however, response rates are modest. We hypothesized that adding stereotactic body radiation therapy (SBRT) to anti-PD-1 would be safe prior to definitive surgical resection and would enhance pathological response compared with historical cohorts of patients with locoregionally advanced HNSCC treated with checkpoint inhibitor alone.

METHODS

The Neoadjuvant Immuno-Radiotherapy Trial was an investigator-initiated single institution phase Ib clinical trial that enrolled patients with previously untreated locally advanced HPV-positive and HPV-negative HNSCC between 2018 and 2019. Eligible patients were treated with neoadjuvant SBRT at a total dose of either 40 Gy in 5 fractions or 24 Gy in 3 fractions, delivered in a 1-week timespan, with or without nivolumab, prior to definitive surgical resection. Patients were then planned for treatment with adjuvant nivolumab for 3 months. The primary safety endpoint was unplanned delay in surgery considered to be at least possibly related to neoadjuvant treatment. The primary efficacy endpoints included pathological complete response (pCR), major pathological response (mPR), and the rate of clinical to pathological downstaging after neoadjuvant treatment.

RESULTS

Twenty-one patients underwent neoadjuvant treatment, which was well tolerated and did not delay surgery, thus meeting the primary endpoint. Tissue responses were characterized by robust inflammatory infiltrates in the regression bed, plasma cells and cholesterol clefts. Among the entire study group, the mPR and pCR rate was 86% and 67%, respectively. Clinical to pathological downstaging occurred in 90% of the patients treated.

CONCLUSION

These data demonstrate that radiation delivered only to the gross tumor volume combined with immunotherapy was safe, resulted in a high rate of mPR and should be further evaluated as a locally focused neoadjuvant therapy for patients with head and neck cancer.

TRIAL REGISTRATION NUMBER

This study is registered with clinicaltrials.gov (NCT03247712) and is active, but closed to patient accrual.

Management of Zygomaticomaxillary Complex Fractures Utilizing Intraoperative 3-Dimensional Imaging: The ZYGOMAS Protocol

PURPOSE

Utilization of technology to aid in the assessment, planning, and management of complex craniomaxillofacial injuries is increasingly common. Limited data exist regarding the implication of intraoperative CT/3-Dimensional imaging on decision making in the management of zygomaticomaxillary complex (ZMC) fractures. This study characterizes the utilization of the intraoperative CT scanner for ZMC fracture surgery and analyzes the impact of the intraoperative CT scanner on fracture management. Using these findings, we sought to propose an algorithm to guide the appropriate utilization of intraoperative 3-Dimensional imaging in ZMC fracture surgery.

METHODS

This retrospective case series evaluates the use of the intraoperative CT scanner for orbitozygomatic trauma surgery at a level 1 trauma center from February 2011 to September 2016. We evaluated the preoperative CT images assessing for the number of displaced sutures, the presence of adjacent fractures requiring fixation, the presence of comminution of the zygomaticomaxillary buttress or body of the zygoma, as well as the number of axes displaced ≥ 5 mm. This information was evaluated to provide guidance on the appropriate utilization of the intraoperative scanner in ZMC fracture management.

RESULTS

A total of 71 patients were identified to have intraoperative facial CT scans and surgery for ZMC fractures over the study time period. There was a 23.9% (17/71) CT directed revision rate. There was a significantly increased likelihood of CT directed revision for fractures with adjacent fractures requiring fixation, and those with ≥ 2 axes displaced ≥ 5 mm. Using these findings, we proposed the ZYGOMAS algorithm outlining the indications for use of intraoperative CT in management of ZMC fractures.

CONCLUSIONS

If available, intraoperative CT/3-Dimensional imaging should be utilized in the management of ZMC fractures with the requirement for orbital floor reconstruction, where adjacent fractures require fixation and/or when ≥ 2 axes are displaced ≥ 5 mm.

A novel surgeon credentialing and quality assurance process using transoral surgery for oropharyngeal cancer in ECOG-ACRIN Cancer Research Group Trial E3311

PURPOSE

Understanding the role of transoral surgery in oropharyngeal cancer (OPC) requires prospective, randomized multi-institutional data. Meticulous evaluation of surgeon expertise and surgical quality assurance (QA) will be critical to the validity of such trials. We describe a novel surgeon credentialing and QA process developed to support the ECOG-ACRIN Cancer Research Group E3311 (E3311) and report outcomes related to QA.

PATIENTS AND METHODS

E3311 was a phase II randomized clinical trial of transoral surgery followed by low- or standard-dose, risk-adjusted post-operative therapy with stage III-IVa (AJCC 7th edition) HPV-associated OPC. In order to be credentialed to accrue to this trial, surgeons were required to demonstrate active hospital credentials and technique-specific surgical expertise with ≥20 cases of transoral resection for OPC. In addition, 10 paired operative and surgical pathology reports from the preceding 24 months were reviewed by an expert panel. Ongoing QA required <10% rate of positive margins, low oropharyngeal bleeding rates, and accrual of at least one patient per 12 months. Otherwise surgeons were placed on hold and not permitted to accrue until re-credentialed using a new series of transoral resections.

RESULTS

120 surgeons trained in transoral minimally invasive surgery applied for credentialing for E3311 and after peer-review, 87 (73%) were approved from 59 centers. During QA on E3311, positive final pathologic margins were reported in 19 (3.8%) patients. Grade III/IV and grade V oropharyngeal bleeding was reported in 29 (5.9%) and 1 (0.2%) of patients.

CONCLUSIONS

We provide proof of concept that a comprehensive credentialing process can support multicenter transoral head and neck surgical oncology trials, with low incidence of positive margins and *grade III/V oropharyngeal bleeding.

Transoral robotic surgery and neck dissection for HPV-positive oropharyngeal carcinoma: Importance of nodal count in survival

BACKGROUND

In this study we determine the survival in patients with HPV-positive oropharyngeal carcinoma treated with transoral robotic surgery (TORS), neck dissection and risk-adapted adjuvant therapy.

METHODS

We retrospectively identified 122 patients with HPV-positive oropharyngeal carcinoma treated with TORS and neck dissection between 2011 and 2018. Survival probability was calculated. We determined the effect of the type of neck dissection performed (modified radical neck dissection-MRND vs. selective neck dissection - SND), extranodal extension (ENE), margin status, and presence of ≥ 5 metastatic nodes on survival.

RESULTS

Our patient population had a five-year overall survival of 91.0% (95% C.I. 85-97%). The five-year probability of recurrence or cancer-associated death was 0.0977 (95% C.I. 0.0927-0.1027). The five-year probability of cancer-associated death was 0.0528 (95% C.I. 0.048-0.0570). All patients who died of their disease had distant metastasis. Our PEG dependence rate was 0%. Patients with ENE and positive margins who underwent adjuvant chemoradiation did not have worse survival. Presence of ≥ 5 metastatic nodes portended worse survival after controlling for age, positive ENE and margins. Low yield (<18 nodes) on neck dissection worsened DFS on multivariable analysis. Furthermore, patients who underwent SND did not have worse OS than those who underwent MRND.

CONCLUSION

Our study demonstrates that surgery could be simplified by performing TORS with SND rather than MRND. The one true poor prognostic factor in HPV-positive oropharyngeal carcinoma patients who undergo surgery is high nodal burden. Patients with high nodal burden are much more likely to die from their disease.

Abstract B01: Surgical outcomes following neoadjuvant hypofractionated radiation in combination with nivolumab: High rate of pathologic complete response in patients with p16+ head and neck squamous cell carcinoma

Hypothesis: Hypofractionated radiation therapy (HFRT) in combination with checkpoint blockade may modulate the tumor microenvironment to induce favorable antitumor immune responses and enhance surgical resection.

Purpose: The purpose of this first-in-human phase Ib clinical trial was to test the safety and immunologic effects of neoadjuvant immunoradiotherapy prior to surgery in patients with head and neck squamous cell carcinoma (HNSCC) (NCT03247712).

Methods: Patients with previously untreated stage I-III (AJCC 8th Ed) p16 positive squamous cell carcinoma of the oropharynx (OPSCC) or cervical lymph nodes from an unknown primary (SCCUP) were eligible to enroll. Neoadjuvant treatment consisted of sandwich nivolumab in combination with HFRT to gross tumor volume in one of two dose-finding cohorts of 8Gy x5 (Monday-Friday) or 8Gy x3 (Monday-Wednesday-Friday), followed five weeks later by definitive surgical resection. The primary endpoint was &lt; 33% unplanned surgical delay; secondary endpoint was pathologic response. Surgical complications were assessed using the Clavien-Dindo scale, a validated scoring tool for surgical complications, applied for 90 days postoperatively. Serial blood and tissue specimens were obtained longitudinally for immunogenomic changes over time.

Results: 10 patients (stage: T0N1M0, N=3; T1N1M0, N=1; T2N1M0, N=6) enrolled and underwent neoadjuvant immunoradiotherapy prior to surgery with curative intent, which consisted of selective neck dissection (level II-IV) and transoral robotic assisted oropharyngectomy for patients with mucosal disease. Surgery was safely performed in all patients without delay, thus meeting the primary endpoint. 7 patients demonstrated a partial radiologic response (PR) by RECIST criteria prior to surgery and 3 patients had stable disease (SD). The pathologic complete response rate (pCR) was 90% (8GyX5 cohort=5/5; 8GyX3 cohort=4/5) with the remaining patient achieving a major pathologic response (MPR; &lt;10% viable tumor cells). All patients were successfully downstaged prior to surgery (ypT0N0M0=9; ypT0N1M0=1) and no patient required adjuvant radiation or chemoradiation. Grade 3 surgical complications as assessed by Clavien-Dindo occurred in 3/5 patients in the 8Gy X5 cohort, but there were no grade 3 or 4 complications in in the 8Gy X3 cohort. All patients are alive without evidence of disease (median follow-up &lt;1 year).

Conclusions: Neoadjuvant HFRT in combination with nivolumab is safe, does not delay definitive surgical resection, and results in significant downstaging with major pathologic response. A lower toxicity profile favors a radiation dose of 8Gy x3 for future development in both human papilloma virus (HPV)-related and HPV-unrelated HNSCC.

Citation Format: R. Bryan Bell, Rom Leidner, Marcus Couey, Ashish Patel, Amber Watters, Hong Ziao, Carlo Bifulco, Brian Piening, George Morris, Lessli Rushforth, Dawn Brucker, Shoren Nemeth, Kristina Young, Michael Gough, Marka Crittenden. Surgical outcomes following neoadjuvant hypofractionated radiation in combination with nivolumab: High rate of pathologic complete response in patients with p16+ head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; 2019 Apr 29-30; Austin, TX. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(12_Suppl_2):Abstract nr B01.

A History of Orthognathic Surgery in North America

This review highlights the contributions of American oral and maxillofacial surgeons to the field of orthognathic surgery. The present state of the art and science of orthognathic surgery is the harvest of yesterday's innovation and research. An improved understanding of the biological and surgical principles and the routine involvement of orthodontics have fueled widespread adoption of a coordinated approach to the treatment of dentofacial problems. Technologic advances in rigid internal fixation, virtual surgical planning with computer-aided manufacturing of occlusal splints and cutting guides, custom implants, and worldwide interest in the correction of dentofacial and craniofacial deformities have resulted in highly predictable, efficient, and safe treatment, which scarcely resembles the situation 70 years ago.

The Society for Immunotherapy of Cancer consensus statement on immunotherapy for the treatment of squamous cell carcinoma of the head and neck (HNSCC)

Head and neck cancers, including those of the lip and oral cavity, nasal cavity, paranasal sinuses, oropharynx, larynx and nasopharynx represent nearly 700,000 new cases and 380,000 deaths worldwide per annum, and account for over 10,000 annual deaths in the United States alone. Improvement in outcomes are needed for patients with recurrent and or metastatic squamous cell carcinoma of the head and neck (HNSCC). In 2016, the US Food and Drug Administration (FDA) granted the first immunotherapeutic approvals - the anti-PD-1 immune checkpoint inhibitors nivolumab and pembrolizumab - for the treatment of patients with recurrent squamous cell carcinoma of the head and neck (HNSCC) that is refractory to platinum-based regimens. The European Commission followed in 2017 with approval of nivolumab for treatment of the same patient population, and shortly thereafter with approval of pembrolizumab monotherapy for the treatment of recurrent or metastatic HNSCC in adults whose tumors express PD-L1 with a ≥ 50% tumor proportion score and have progressed on or after platinum-containing chemotherapy. Then in 2019, the FDA granted approval for PD-1 inhibition as first-line treatment for patients with metastatic or unresectable, recurrent HNSCC, approving pembrolizumab in combination with platinum and fluorouracil for all patients with HNSCC and pembrolizumab as a single agent for patients with HNSCC whose tumors express a PD-L1 combined positive score ≥ 1. These approvals marked the first new therapies for these patients since 2006, as well as the first immunotherapeutic approvals in this disease. In light of the introduction of these novel therapies for the treatment of patients with head and neck cancer, The Society for Immunotherapy of Cancer (SITC) formed an expert committee tasked with generating consensus recommendations for emerging immunotherapies, including appropriate patient selection, therapy sequence, response monitoring, adverse event management, and biomarker testing. These consensus guidelines serve as a foundation to assist clinicians' understanding of the role of immunotherapies in this disease setting, and to standardize utilization across the field for patient benefit. Due to country-specific variances in approvals, availability and regulations regarding the discussed agents, this panel focused solely on FDA-approved drugs for the treatment of patients in the U.S.

Delayed immune-related events (DIRE) after discontinuation of immunotherapy: diagnostic hazard of autoimmunity at a distance

BACKGROUND

The risk of delayed autoimmunity occurring months or years after discontinuation of immunotherapy is frequently asserted in the literature. However, specific cases were rarely described until 2018, when a wave of reports surfaced. With expanding I-O indications in the adjuvant/neoadjuvant curative setting, growing numbers of patients will receive limited courses of immunotherapy before entering routine surveillance. In this context, under-recognition of DIRE could pose a growing clinical hazard.

METHODS

The aim of this study was to characterize DIRE through identification of existing reports of delayed post-treatment irAE in cancer patients treated with immunotherapy. We performed a PubMed literature review from 2008 through 2018 to determine the median data safety reporting window from existing I-O clinical trials, which we then applied to define the DIRE cutoff, and collated all qualifying reports over the same time span. DIRE was defined as new immune-related adverse events (irAE) manifesting ≥90 days after discontinuation of immunotherapy.

RESULTS

Median duration of I-O clinical trials data safety reporting was 90 days (82% ≤ 90 days). DIRE cutoff was thus set as ≥90 days post-immunotherapy. We identified 23 qualifying cases; 21 by literature review and 2 from our institution. Median off-treatment interval to DIRE was 6 months (range: 3 to 28). Median cumulative immunotherapy exposure was 4 doses (range: 3 to 42). Involvement included endocrine, neurologic, GI, pulmonary, cardiac, rheumatologic and dermatologic irAE.

CONCLUSIONS

As immunotherapy indications expand into the curative setting, often with brief exposure and potentially sequenced with multimodality treatments, it will be necessary to recognize an emerging diagnostic complex, which we have termed delayed immune-related events (DIRE). Clinical vigilance has the potential to reduce morbidity from diagnostic delay, as irAE are generally manageable with prompt initiation of treatment - or from misdiagnosis - as misattribution can lead to unnecessary or harmful interventions as we describe. DIRE should therefore figure prominently in the differential diagnosis of patients presenting with illnesses of unclear etiology, irrespective of intervening treatments or interval post-immunotherapy, both of which can confound diagnosis. Increased recognition will rest on delineation of DIRE as a clinical diagnostic entity.

Abstract CT182: Neoadjuvant immuno-radiotherapy (NIRT) in head and neck cancer: Phase I/Ib study of combined PD-1/SBRT prior to surgical resection

Background: Standard treatment of locally advanced HPV-associated oropharyngeal HNSCC includes definitive chemoRT or surgery followed by risk-adapted adjuvant RT +/- chemo. These approaches provide high rates of long term survival, but are associated with significant subacute as well as long term morbidity. Therefore, increasing efforts have been directed at exploring alternative approaches. Combined SBRT and PD-1 blockade may have particularly favorable properties for anti-tumor immune response in HNSCC (Gough 2009). We present phase I safety & efficacy data from the NIRT trial of neoadjuvant nivolumab/SBRT in oropharyngeal p16+ HNSCC (NCT03247712).

Methods: Patients with p16+ oropharyngeal or unknown primary HNSCC, with clinical indications for adjuvant RT, or upfront TORS ineligible due to tumor size, could enroll. Patients received Nivo 240mg IV q2wks x3 prior to surgery, with SBRT to GTV+3mm delivered between Nivo doses 1 & 2, in two dose finding cohorts (n=5 each): 8Gy x5 daily (M-F) and de-escalated 8Gy x3 (M,W,F). Surgery was performed 5 weeks post-SBRT followed by adjuvant Nivo 480mg IV q4wks x3, starting 4 weeks post-op. The primary endpoint was &lt; 33% unplanned surgical delay; the secondary endpoint was pathologic response by irPRC (Cottrell 2018).

Results: There were no unplanned surgical delays. All patients had radiologic evidence of decreased tumor size prior to surgery, but none showed a CR by RECIST. Remarkably, the pathologic CR rate was 100% in the 8Gy x 5 cohort (5/5) and 80% In the 8 Gy x 3 cohort (4/5), with the remaining patient achieving MPR (major pathologic response; &lt;10% residual viable tumor). G3 toxicity was observed after surgery in both cohorts but was higher in the 8 Gy x 5 cohort. No G4 or higher toxicity was observed. Interestingly, G2 adrenal insufficiency was observed in 50% (5/10), a higher rate than previously reported with PD-1 blockade for recurrent/metastatic HNSCC. Notably, patients did not experience xerostomia or ageusia rates associated with standard adjuvant radiation in HNSCC. Tissue responses were characterized by robust inflammatory infiltrates into the regression bed and cholesterol clefts, as previously described. Circulating immune cells, baseline tissue, end of RT biopsy and surgical specimen were analyzed using flow cytometry and RNAseq to characterize of immunologic changes over time. There have been no local or distant failures, but median follow up remains &lt; 1 year.

Conclusions: Neoadjuvant combined PD-1/SBRT to GTV+3mm dosed at either 8Gy x5 (M-F) or 8Gy x3 (M,W,F) did not delay HNSCC surgery in this Phase I trial (n=10; five per dose). Potent anti-tumor response was observed in all cases (CR=9 + MPR=1). A high response rate and lower toxicity profile favors the 8Gy x3 cohort for development. This study represents a major paradigm shift in the approach to treatment of locally advanced p16+ oropharyngeal cancers.

Citation Format: Rom Leidner, R. Bryan Bell, Kristina Young, Brendan Curti, Marcus Couey, Ashish Patel, Amber Watters, Hong Xiao, Carlo Bifulco, Brian Piening, George Morris, Lessli Rushforth, Dawn Brucker, Shorin Nemeth, Michael Gough, Marka Crittenden. Neoadjuvant immuno-radiotherapy (NIRT) in head and neck cancer: Phase I/Ib study of combined PD-1/SBRT prior to surgical resection [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 CT182.

Four Practical Reconstructive Techniques Using the Transantral Approach to the Orbital Floor Without the Need for an Endoscope

Fractures of the orbital floor have traditionally been treated through transorbital approaches. Transconjunctival approaches risk entropion, whereas transcutaneous approaches risk ectropion or hypertrophic scarring. The intraoral transantral approach to the orbital floor has the advantage of minimizing the risk of any eyelid changes while providing appropriate access to reduce the herniated orbital contents and restore orbital volume. This article describes 4 plating methods for reconstructing a fractured orbital floor using a transantral approach. Many prior descriptions of transantral treatment of the orbital floor have relied heavily on the use of an endoscope. This article describes an osteotomy technique that does not require an endoscope but requires only a high-quality headlight for visualization.

Fibular Reconstruction of the Maxilla and Mandible with Immediate Implant-Supported Prosthetic Rehabilitation: Jaw in a Day

The fibula free flap is a workhorse flap used to reconstruct ablative, osseous defects in the upper and lower jaws. Traditionally, the fibula free flap is inset into the defect freehand; dental implants are placed secondarily; and final prosthetic rehabilitation often occurs more than 1 year after ablative surgery. Virtual surgical planning and rapid prototyping of cutting guides and guide stents for head and neck reconstruction have facilitated improved accuracy in fibular transfer. This article describes the Jaw in a Day technique, allowing maxillary or mandibular resection, fibular free flap reconstruction, immediate implant placement, and prosthetic rehabilitation in a single operation.

Infection prevalence and patterns in self-inflicted gunshot wounds to the face

OBJECTIVE

Self-inflicted gunshot wounds (SIGSWs) to the craniomaxillofacial region are uncommon injuries but are associated with a high mortality rate. Therefore, treating these patients is a rare occurrence even in the largest trauma centers. As with many rare conditions, data specifically addressing this injury pattern are scarce. Because of the proximity of the blast, even low-velocity injuries can be associated with significant avulsion of tissue, comminution of structures, and tissue die back. Previous case reports have recommended the use of prophylactic antibiotics, but no study has specifically investigated the postinjury infection rate or microbial patterns in this patient population. The purpose of this study was to answer the following clinical question: "Among patients with SIGW to the maxillofacial region, what is the prevalence of postinjury infection, and are there any microbial patterns that can guide empiric antibiotic selection?"

STUDY DESIGN

We designed retrospective cohort study at a level I trauma center in Portland, Oregon. Data on 17 patients who had sustained a SIGSW involving the maxilla or the mandible and survived their initial injury were collected from 2010 to 2017.

RESULTS

Patients who had a culture-positive infection within 30 days of their injury were defined to have a postinjury infection. Six of the 17 patients (35%) developed a postinjury infection, with an average time to infection of 11 days from initial injury (range 3-19 days). Of the 17 subjects, 15 (88%) received a course of prophylactic antibiotics, on average, for 14 days (range 3-24 days). Of the 6 cases of postinjury infection, culture grew gram-negative bacteria in 4 cases-anaerobic bacteria in 2 and polymicrobial organisms in 2. There was no clear pattern or prevalence of any specific bacterium, but cultures notably included Staphylococcus aureus, Enterobacter species, Bacteroides species, and Escherichia coli.

CONCLUSIONS

SIGSWs are associated with a high rate of postinjury infection (35%) despite prophylactic antibiotic usage in 88% of these cases. Given the antimicrobial patterns observed in this study, prophylactic antibiotics in this patient population should include empiric coverage for gram-negative and anaerobic bacteria.

Does Mandible-First Sequencing Increase Maxillary Surgical Accuracy in Bimaxillary Procedures?

PURPOSE

In bimaxillary procedures, it is important to know how the chosen sequence affects the surgical outcome. The purpose of this study was to explore whether the theoretical advantages of using the mandible-first procedure were supported by clinical data.

MATERIALS AND METHODS

The authors performed a retrospective investigation on a cohort compiled from 3 published retrospective studies. The sample was composed of patients treated at the Radboud University Nijmegen Medical Centre (Nijmegen, the Netherlands) from 2010 to 2014 and the Odense University Hospital (Odense, Denmark) from 2011 to 2015. The inclusion criterion was bimaxillary surgery without maxillary segmentation. The exclusion criterion was lack of a virtual surgical plan. The primary outcome variable was surgical accuracy, defined as the mean difference between the obtained outcome and the virtual surgical plan. The primary predictor variable was the comparison between mandible-first and maxilla-first sequencing. Secondary predictors were inferior maxillary repositioning and counterclockwise (CCW) rotation. The confounding variable was the virtually planned reposition. Results were analyzed by mixed-model regression encompassing all variables, followed by a detailed analysis of positive results using 2-sample t tests.

RESULTS

Overall, 145 patients were included for analysis (98 women; mean age, 28 years). Operating on the mandible first notably influenced maxillary positioning and placed the maxilla 1.5 mm posterior and with 1.4° of CCW rotation compared with virtual surgical planning. The interaction of surgical sequence with maxillary rotation showed similar surgical accuracy between maxilla-first surgery with clockwise rotation and mandible-first surgery with CCW rotation. Inferior maxillary repositioning resulted in the maxilla being placed 1.7 mm (maxilla-first sequence) and 2.0 mm (mandible-first sequence) posterior to the planned position.

CONCLUSION

Surgical accuracy was considerably influenced by sequencing in bimaxillary procedures. It remains important to know how the chosen sequence affects the surgical outcome so that the virtual surgical plan can be adjusted accordingly.

The Biaxial Double-Barrel Fibula Flap-A Simplified Technique for Fibula Maxillary Reconstruction

PURPOSE

Previously described techniques for microvascular fibula reconstruction of Brown Class II to IV maxillectomy defects are complex, require multiple osteotomies, result in a short pedicle, and inadequately reconstruct the dental alveolus in preparation for endosseous implants. This report describes a simplified technique for Brown Class II to IV defects that re-creates facial support, allows for dental reconstruction with appropriately positioned implants, and maintains adequate pedicle length.

MATERIALS AND METHODS

A retrospective chart review was performed of all patients with Brown Class II to IV maxillectomy defects immediately reconstructed with a biaxial double-barrel fibula flap technique. The reconstructive surgeon evaluated each patient at least 1 month after reconstruction for enophthalmos, facial symmetry, nasal patency, satisfactory jaw position, deglutition, intelligible speech, and intraoperative need for vein grafting.

RESULTS

The sample was composed of 6 patients (mean age, 54 yr; range, 33 to 78 yr; 67% women) who underwent reconstruction with the biaxial double-barrel fibula flap technique for Brown Class II to IV defects. None of these patients required vein grafting. None of these patients had flap failure. Diagnoses for these patients were a hybrid odontogenic tumor (n = 1), squamous cell carcinoma (n = 3), adenoid cystic carcinoma (n = 1), and sinonasal melanoma (n = 1). All 6 patients had excellent facial contour and malar projection, regular oral intake, 100% intelligible speech, and a new maxillary skeletal Class I relation without need for intraoperative vein grafting. One patient developed enophthalmos related to inferior rectus sacrifice and removal of orbital fat. Complications included development of nasal synechia and occlusion of the maxillary sinus ostium (n = 1).

CONCLUSIONS

The biaxial double-barrel fibula flap technique achieves the goals of providing adequate facial support and an alveolar segment amenable to implant dentistry. It allows for intelligible speech, deglutition, orbital support, and separation of the oronasal, orbital, and sinus cavities. In addition, it minimizes the need for vein grafting.

Evaluation of Explant Responses to STING Ligands: Personalized Immunosurgical Therapy for Head and Neck Squamous Cell Carcinoma

Surgeons have unique in situ access to tumors enabling them to apply immunotherapies to resection margins as a means to prevent local recurrence. Here, we developed a surgical approach to deliver stimulator of interferon genes (STING) ligands to the site of a purposeful partial tumor resection using a gel-based biomaterial. In a range of head and neck squamous cell carcinoma (HNSCC) murine tumor models, we demonstrate that although control-treated tumors recur locally, tumors treated with STING-loaded biomaterials are cured. The mechanism of tumor control required activation of STING and induction of type I IFN in host cells, not cancer cells, and resulted in CD8 T-cell-mediated cure of residual cancer cells. In addition, we used a novel tumor explant assay to screen individual murine and human HNSCC tumor responses to therapies ex vivo We then utilized this information to personalize the biomaterial and immunotherapy applied to previously unresponsive tumors in mice. These data demonstrate that explant assays identify the diversity of tumor-specific responses to STING ligands and establish the utility of the explant assay to personalize immunotherapies according to the local response.Significance: Delivery of immunotherapy directly to resection sites via a gel-based biomaterial prevents locoregional recurrence of head and neck squamous cell carcinoma. Cancer Res; 78(21); 6308-19. ©2018 AACR.

Patient-Specific Printed Plates Improve Surgical Accuracy In Vitro

PURPOSE

It remains unclear to what extent patient-specific printed plates can improve surgical outcomes in orthognathic procedures. This study aimed to quantify the surgical accuracy of patient-specific printed plates in vitro and to compare the results with patients' actual surgical outcomes.

PATIENTS AND METHODS

This in vitro study enrolled 20 postoperative orthognathic surgical patients, all treated with inferior maxillary repositioning. The preoperative midfaces were re-created in a 3-dimensionally printed model. The osteotomy and screw holes were placed at prespecified positions using a 3-dimensional guide. The dental segment was repositioned by means of the patient-specific plates. The primary outcome was the mean reposition at 3 dental reference points. The primary predictor variable was the obtained surgical reposition in vitro compared with the virtual surgical plan. Confounding variables were gender, age, occlusion, and bimaxillary surgery. The secondary outcome was surgical accuracy, and the secondary predictor was the in vitro outcomes versus the patients' surgical outcomes. Surgical accuracy was defined as the difference between the obtained reposition and the virtual surgical plan on a continuous scale. The differences were recorded in 3 dimensions according to the positive value of the 3 axes: right, anterior, and posterior. The results were analyzed using mixed-model regression and 1-sample t tests.

RESULTS

In the 20 patients (age, 18 to 64 years; 40% of patients were women), the mean planned reposition was 2.9 mm anterior and 1.8 mm inferior. In all models, the osteotomy edge was rounded off to position the plate in the predetermined position. Overall, the maxilla was positioned 0.5 mm anterior and 0.3 mm inferior to the planned position using patient-specific plates.

CONCLUSIONS

The patient-specific plates positioned the maxilla in close approximation to the planned position without surgically relevant differences. The osteotomy edge must be carefully inspected for interference with the patient-specific plates to avoid displacement of the planned maxillary repositioning.

Neoadjuvant OX40 therapy in patients with head and neck cancer induces profound changes in tumor-infiltrating lymphocytes

OX40 is a member of the tumor necrosis factor (TNF) receptor family and, as a co-stimulatory molecule, enhances T-cell proliferation, survival and memory formation. We have also shown that it induces robust antitumor responses in patients with metastatic disease. To examine the effect of OX40 stimulation on the immune response in cancer patients, 16 head and neck squamous cell carcinoma (HNSCC) patients were enrolled in a neoadjuvant phase Ib trial and received anti-OX40 infusion 2 days, 1 week and 2 weeks prior to surgical resection.

To evaluate changes in the tumor microenvironment (TME), tissue and peripheral blood samples were obtained prior to infusion and at time of surgery. Assessment of changes in tumor infiltrating lymphocyte (TIL) and peripheral blood populations were performed by flow cytometry and fluorescent multiplex immunohistochemistry (IHC).

OX40 administration was well tolerated with low toxicity. Activation and proliferation of CD4+ and CD8+ memory T-cell populations in both the TME and periphery peaked between 12 and 19 days after OX40 infusion, as demonstrated by increased levels of Ki67, CD38 and ICOS. In the TIL, expression of CD39, ICOS and PD-1 was increased on CD4+ T cells in most patients and the frequency of tumor-reactive CD39+CD103+ CD8+ T cells was increased in some patients. IHC analysis revealed striking changes in tissue integrity and increased lymphocyte infiltrates in 4/16 patients.

With this study, we have found that neoadjuvant OX40 immunotherapy is feasible and safe in patients with HNSCC and results in robust activation and proliferation of T cells within the tumor. Based on these findings, we are now comparing the transcriptome and changes in TIL repertoire and metabolism before and after treatment.

Margin Analysis: Squamous Cell Carcinoma of the Oropharynx

Because of the common shared risk factors of smoking and heavy alcohol consumption, literature involving oropharyngeal squamous cell carcinoma (OPSCC) is often combined with oral squamous cell carcinoma. Human papilloma virus is now confirmed to be a major risk factor of OPSCC with its distinct epidemiology and favorable treatment outcome. The impact of adjuvant chemoradiation in the setting of positive surgical margins remains unclear but is likely influenced by tumor biology. This article reviews the tumor biology of OPSCC and summarizes recent findings on outcomes following surgical treatment of OPSCC.

Correction: STING expression and response to treatment with STING ligands in premalignant and malignant disease

[This corrects the article DOI: 10.1371/journal.pone.0187532.].

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

Expert Opinion vs Patient Perspective in Treatment of Rare Disorders: Tooth Removal in Lesch-Nyhan Disease as an Example

Treatment recommendations for rare disorders often are limited by a lack of data from objective clinical trials. As a result, recommendations are often based on expert opinion. Because expert opinions sometimes conflict, many patients turn to the Internet for guidance from others who may have tried a treatment. The increasing numbers of patients and families who post opinions regarding outcomes allow for systematic data collection regarding specific treatments from the patient perspective. We used social media research methods to determine the opinions of family members or other caregivers regarding permanent removal of teeth for treatment of self-injurious biting (SIB) in patients with Lesch-Nyhan disease (LND), a particularly difficult treatment decision where expert opinion is divided. A content analysis of social media postings was used to systematically interpret caregiver posts about tooth extraction from families and other caregivers of patients with LND who posted comments regarding physical or emotional well-being after tooth extraction. A scale was used to rate all posted opinions. Scores ranged from 1 to 5, with 1 being completely negative and 5 being completely positive. 170 comments from 46 unique individuals were collected and scored by two raters. Inter-rater reliability, determined using a correlation coefficient across all postings, was 0.85, suggesting a high degree of reliability. The overall average caregiver sentiment score was 4.86, which is an overwhelmingly positive endorsement of tooth extraction as a means for controlling SIB. These methods provide a simple strategy for recommending treatment strategies based on real-world experience when objective clinical trials are unviable.

Abstract 38: Development of a DC-targeted microvesicle vaccine to intercept the progression of oral preneoplasia to cancer

Background: HPV negative oral squamous cell carcinoma (OSCC) is diagnosed in more than 300,000 people each year worldwide and more than half of these will die within five years despite standard treatment. These cancers are often preceded by the appearance of a preneoplastic lesion, which offers a unique opportunity to identify patients at high risk of developing OSCC and offer them a vaccine that may prevent development of this non-viral cancer. Cancer cell line-derived proteasome-blocked autophagosomes are DC-targeted microvesicles containing tumor-derived short-lived proteins (SLiPs) and defective ribosomal products (DRiPs). SLiPs and DRiPs are short-lived because they are targeted to and degraded by the proteasome, explaining why they are thought to make up the dominant epitopes presented on the surface of cancer cells. This may explain their ability to induce broad anticancer immunity in preclinical models and in patients receiving the vaccine. The human vaccine studied here, DPV-001, was derived from two cancer cell lines. Characterization of the vaccine by mass spectroscopy identified that the vaccine contains more than 100 antigens whose genes are over-expressed by most cancers. Many of these antigens have single amino acid variants that may serve as immunogenic mimetopes, or altered peptide ligands. Further, DPV-001 contains at least 13 antigens from the NCI priority list and multiple toll-like receptor (TLR) agonists packaged into stable double membrane microvesicles that are targeted to CLEC9A+ antigen presenting cells (APCs). We recently reported that every patient receiving vaccine in an NCI-supported phase I/II trial developed or augmented immunity against a large number of putative cancer antigens.

Methods: Recently, gene sets developed from a preclinical 4-NQ0 mouse model of oral cancer were shown to enrich for patients with oral preneoplasia that progressed to squamous cell carcinoma (p=0.0495, Foy J-P, 2016). The progressive gene set (PGS) contained 162 genes and we compared this list to results of mass spectroscopy analysis of the DPV-001 vaccine.

Results: 94 of the 162 genes contained in the PGS, which enriched for patients with poor oral cancer-free survival, were identified in the DPV-001 vaccine.

Conclusions: DPV-001 contains more than 90 proteins for genes (PGS) whose over-expression is associated with progression of oral preneoplasia to OSCC. Based on significant preclinical data documenting induction of protective or therapeutic immunity in animals receiving a DRibble vaccine, coupled with safety data from a phase I/II clinical trial, and evidence that vaccination induces broad immunity against putative cancer antigens in every patient studied to date, we are proposing a pilot clinical trial of DPV-001 in patients with severe oral dysplasia.

Citation Format: R. Bryan Bell, Rom Leidner, Carlo B. Bifulco, Christopher Dubay, Tarsem Moudgil, Sam Bookhardt, Glenna McDonnell, Christopher Paustian, Hong-Ming Hu, Walter J. Urba, Traci L. Hilton, Bernard Fox. Development of a DC-targeted microvesicle vaccine to intercept the progression of oral preneoplasia to cancer [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 38.

Abstract 31: The INSPIRE trial: A randomized trial of neoadjuvant and adjuvant therapy with the IRX-2 regimen in patients with newly diagnosed stage II, III, or IVa squamous cell carcinoma of the oral cavity

Introduction: IRX-2 is a primary-cell-derived immune-restorative biologic consisting of a well-defined set of human cytokines that act on multiple immune system cell types to overcome tumor-mediated immunosuppression. The IRX-2 biologic stimulates T cells and natural killer cells and turns immature or defective dendritic cells into mature antigen-presenting cells. The IRX-2 biologic is provided as part of the IRX-2 regimen, which contains cyclophosphamide, indomethacin, and zinc to support an anticancer immune response. In a phase 2a clinical trial in 27 patients with therapy-naïve head and neck squamous cell carcinoma (HNSCC), treatment with the IRX-2 regimen was well tolerated and associated with immunologically mediated antitumor effects. The new multicenter randomized IRX-2 Neoadjuvant Therapy in Head and Neck SCC to Provide Immune Response Enhancement (INSPIRE) trial (NCT02609386) is designed to evaluate the safety and effectiveness of combined neoadjuvant and adjuvant therapy with the IRX-2 regimen in patients with oral cavity HNSCC, a disease known to have a disordered immune function.

Study Design: Patients enrolled in INSPIRE must be at least 18 years of age; have previously untreated Stage II, III, or IVa SCC of the oral cavity that is surgically resectable with curative intent; and have a Karnofsky Performance status ≥70%. Up to 200 patients will be randomized 2:1 to either the IRX-2 biologic regimen arm or the IRX-2 regimen control arm (the IRX regimen minus the IRX-2 biologic).

The neoadjuvant stage of INSPIRE begins 21 days before resection, when patients in both treatment arms will receive the IRX-2 regimen each day until resection. This regimen consists of the immunomodulatory chemotherapeutic agent cyclophosphamide, provided as a low-dose intravenous infusion, as well as two oral drugs, a zinc-containing multivitamin and indomethacin, a nonselective COX-1/COX-2 inhibitor. During this period, patients in the IRX-2 biologic regimen arm will also receive 10 days of the IRX-2 biologic subcutaneously injected into their bilateral sternocleidomastoid insertion regions.

After resection, patients receive standard adjuvant radiation or chemoradiation therapy followed by adjuvant IRX-2 booster regimens at 3, 6, 9, and 12 months. During each 10-day booster period, patients in the IRX-2 biologic regimen arm also receive, for 5 consecutive days, the IRX-2 biologic subcutaneously injected into their bilateral deltoid regions.

Study Endpoints: INSPIRE is now enrolling patients at 12 selected institutions in the United States. The primary endpoint of INSPIRE is event-free survival (EFS). Secondary endpoints include overall survival (OS) and safety as assessed by the incidence and severity of adverse events. Exploratory endpoints include changes in tumor size and histologic differences between pre- and post-treatment specimens in lymphocytic infiltration, assessed by both cell-surface marker expression (Perkin Elmer multiplex IHC) and immune cell gene signatures (NanoString).

Conclusion: With enrollment of up to 200 patients, the randomized INSPIRE trial provides the opportunity to assess the ability of the IRX-2 regimen to improve EFS and OS by inhibiting tumor-mediated immunosuppression. Analysis of the exploratory endpoints will generate data to better describe the mechanism of action of the IRX-2 regimen and provide insight into the differences between inflammatory and non-inflammatory responses to SCCs of the oral cavity.

Citation Format: Gregory T. Wolf, Mihir Patel, Audrey Erman, Jason G. Newman, Greg Krempl, Jorge Nieva, R. Bryan Bell, Michael Kaplan, Dennis Kraus, Jeffrey Moyer, Aru Panwar, Joseph Valentino. The INSPIRE trial: A randomized trial of neoadjuvant and adjuvant therapy with the IRX-2 regimen in patients with newly diagnosed stage II, III, or IVa squamous cell carcinoma of the oral cavity [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 31.

Abstract 37: Anti-OX40 (MEDI6469) prior to definitive surgical resection in patients with head and neck squamous cell carcinoma

Background: Head and neck squamous cell carcinomas (HNSCC) produce suppressive factors that impair the immune system, thus limiting effective antitumor immunity. OX40 is a member of the tumor necrosis factor (TNF) receptor family and its biologic activity leads to potent co-stimulation, which can enhance T-cell memory, proliferation and antitumor activity in patients with metastatic cancer. However, its effect on wound healing and the optimal timing of administration in relation to surgery to induce immune changes within the tumor microenvironment (TME) is not known.

Objectives: To determine the safety and peak immunologic activity of neoadjuvant anti-OX40 treatment administered prior to definitive surgical resection in patients with locoregionally advanced HNSCC.

Methods: Between January 2016 and July 2016, 10 patients with locoregionally advanced HNSCC were enrolled into this phase Ib neoadjuvant time course trial testing a murine antibody to OX40 (MEDI6469) administered 2 days, 1 week and 2 weeks prior to definitive surgical resection. In order to assess changes in the tumor microenvironment (TME), a tissue biopsy and peripheral blood samples were obtained prior to MEDI6469 infusion and tissue was also harvested at the time of surgical resection from the primary tumor site, metastatic and draining lymph nodes along with peripheral blood. Assessments of tumor infiltrating lymphocyte (TIL) populations were performed based on flow cytometry and fluorescent multiplex immunohistochemistry (mIHC); other circulating immunologic parameters that correlate with changes induced by MEDI6469 administration were also measured. These immune changes were assessed and compiled in a “cumulative suppression index,” which incorporates immunosuppressive elements within the tumor, such as FoxP3+ and PD-L1+ cells, to be correlated with clinical variables and outcome. Surgical complications were described using the Clavien-Dindo grading scale. Clinical trial information: NCT02274155.

Results: MEDI6469 administration was well tolerated and there were no grade 3 or 4 adverse events (AEs) attributable to anti-OX40 treatment. The toxicity profile was mild, most commonly consisting of low-grade fever prior to surgery, which was performed in all patients without delay. Postoperative grade 3 and 4 complications per Clavien-Dindo scale were observed in two patients. Immunologic changes were observed at all time courses with significant activation and proliferation of CD4+ and CD8+ central and effector memory T-cell populations in both the TME and circulation occurring between 12 and 19 days following MEDI6469 infusion. Ki67 was specifically induced in the TME and on peripheral blood PBMCs after MEDI6469 administration, returning to baseline at Day 55. Up-regulation of PD-L1 was also seen in the tumor post treatment in the majority of specimens. In the tumor, expression of CD39, ICOS and PD-1 is increased on CD4+ T cells in almost all patients and a recently identified tumor-reactive T-cell subset of CD39+CD103+CD8+ T cells, with resident memory phenotype, was increased in some patients.

Conclusion: Preoperative MEDI6469 administration prior to surgery is feasible and safe in patients with HNSCC and results in activation and proliferation of T cell populations and up-regulation of PD-L1 in tumor cells occurring between 12 and 19 days following infusion.

Citation Format: R. Bryan Bell, Rom S. Leidner, Rebekka A. Duhen, Carmen Ballesteros-Merino, Zipei Feng, Yoshinobu Koguchi, Carlo B. Bifulco, Brendan D. Curti, Walter J. Urba, Bernard A. Fox, Andrew D. Weinberg. Anti-OX40 (MEDI6469) prior to definitive surgical resection in patients with head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 37.

STING expression and response to treatment with STING ligands in premalignant and malignant disease

Human papilloma virus positive (HPV⁺) tumors represent a large proportion of anal, vulvar, vaginal, cervical and head and neck squamous carcinomas (HNSCC) and late stage invasive disease is thought to originate from a premalignant state. Cyclic dinucleotides that activate STimulator of INterferon Genes (STING) have been shown to cause rapid regression of a range of advanced tumors. We aimed to investigate STING ligands as a novel treatment for papilloma. We tested therapies in a spontaneous mouse model of papilloma of the face and anogenital region that histologically resembles human HPV-associated papilloma. We demonstrate that STING ligands cause rapid regression of papilloma, associated with T cell infiltration, and are significantly more effective than Imiquimod, a current immunotherapy for papilloma. In humans, we show that STING is expressed in the basal layer of normal skin and lost during keratinocyte differentiation. We found STING was expressed in all HPV-associated cervical and anal dysplasia and was strongly expressed in the cancer cells of HPV⁺ HNSCC but not in HPV-unrelated HNSCC. We found no strong association between STING expression and progressive disease in non-HPV oral dysplasia and oral pre-malignancies that are not HPV-related. These data demonstrate that STING is expressed in basal cells of the skin and is retained in HPV⁺ pre-malignancies and advanced cancers, but not in HPV-unrelated HNSCC. However, using a murine HNSCC model that does not express STING, we demonstrate that STING ligands are an effective therapy regardless of expression of STING by the cancer cells.

Multiparametric immune profiling in HPV- oral squamous cell cancer

Evaluation of T lymphocyte frequency provides prognostic information for patients with oral squamous cell cancer (OSCC). However, the effect of simultaneously evaluating T cell frequency and assessing suppressive elements and defects in antigen-processing machinery (APM) has not been clarified. Simultaneous characterization of CD3+, CD8+, FoxP3+, CD163+, and PD-L1+ cells using multispectral imaging was performed on sections from 119 patients with HPV- OSCC. Expression of β2-microglobulin, MHC class I heavy chain, and large multifunctional peptidase 10 was quantified, and all data were correlated with patient outcome. We found that, consistent with previous reports, high numbers of CD8+ T cells at the invasive margin correlated significantly with prolonged overall survival (OS), while the number of FoxP3+ or PD-L1+ cells did not. Compiling the number of FoxP3+ or PD-L1+ cells within 30 μm of CD8+ T cells identified a significant association with a high number of suppressive elements close to CD8+ T cells and reduced OS. Integrating this information into a cumulative suppression index (CSI) increased correlation with OS. Incorporating tumor expression levels of APM components with CSI further improved prognostic power. This multiparametric immune profiling may be useful for stratifying patients with OSCC for clinical trials.