Defining the Prevalence and Prognostic Value of Perineural Invasion and Angiolymphatic Invasion in Human Papillomavirus-Positive Oropharyngeal Carcinoma

IL-1R signaling drives enteric glia-macrophage interactions in colorectal cancer

Enteric glia have been recently recognized as key components of the colonic tumor microenvironment indicating their potential role in colorectal cancer pathogenesis. Although enteric glia modulate immune responses in other intestinal diseases, their interaction with the colorectal cancer immune cell compartment remains unclear. Through a combination of single-cell and bulk RNA-sequencing, both in murine models and patients, here we find that enteric glia acquire an immunomodulatory phenotype by bi-directional communication with tumor-infiltrating monocytes. The latter direct a reactive enteric glial cell phenotypic and functional switch via glial IL-1R signaling. In turn, tumor glia promote monocyte differentiation towards pro-tumorigenic SPP1+ tumor-associated macrophages by IL-6 release. Enteric glia cell abundancy correlates with worse disease outcomes in preclinical models and colorectal cancer patients. Thereby, our study reveals a neuroimmune interaction between enteric glia and tumor-associated macrophages in the colorectal tumor microenvironment, providing insights into colorectal cancer pathogenesis.

Association of adjuvant radiation and survival in human papilloma virus-positive oropharynx squamous cell carcinoma with lymphovascular invasion as the sole adverse pathologic feature

BACKGROUND

Postoperative radiotherapy radiation therapy (PORT) for early-stage human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) with positive lymphovascular invasion (LVI) has an unclear association with overall survival (OS).

METHODS

This retrospective cohort study queried the National Cancer Database for surgically treated, T1-2, N0-1 HPV+ OPSCC from 2010 to 2019. Primary exposures were LVI and PORT, and the main outcome was 5-year OS. Odds ratios and hazard ratios (HR) with 95% confidence intervals (CIs) were generated using multivariable models and Cox proportional hazard models, respectively.

RESULTS

Of 2768 patients, average age was 59.3 years, 2207 (79.7%) were male, and 386 (13.9%) had LVI. Of patients with LVI as their sole adverse pathologic feature, 220 (57.0%) received PORT, which was not associated with 5-year OS (HR, 1.13; CI, 0.65-1.19).

CONCLUSIONS

Patients with surgically treated, early-stage HPV+ OPSCC and positive LVI as their only pathologic adverse feature may not require PORT.

Effect of palatine tonsil tumor resection on postoperative velopharyngeal insufficiency in transoral surgery

BACKGROUND

Velopharyngeal insufficiency (VPI) is a known complication of transoral surgery (TOS) for oropharyngeal HPV-mediated squamous cell carcinoma. Controversy exists regarding adequate resection margins for balancing functional and oncologic outcomes.

METHODS

This retrospective study was exempted by the IRB. Patients who underwent TOS from January 2017 to October 2022 were included. Patient characteristics, treatment details, and oncologic and functional outcomes were evaluated.

RESULTS

Fifty-five patients were included. Mean and median follow-up was 34 months. 98% of patients were AJCC stage I/II. Recurrence-free survival was 96% with no local recurrences. Univariate analysis demonstrated an association between VPI and pT stage (p = 0.035), medial pterygoid resection (p = 0.049), and palatal attachment sacrifice (p < 0.001). Multivariate analysis showed sacrifice of the palatal attachments remained a significant risk for VPI (p = 0.009).

CONCLUSION

Loss of soft palate pharyngeal attachments is an independent risk factor for VPI. When oncologically appropriate, the palatal attachments to the pharynx may be preserved.

Clinical, morphologic and molecular heterogeneity of HPV-associated oropharyngeal cancer

The incidence of human papillomavirus-positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is rising rapidly and has exceeded cervical cancer to become the most common HPV-induced cancer in developed countries. Since patients with HPV + OPSCC respond very favorably to standard aggressive treatment, the emphasis has changed to reducing treatment intensity. However, recent multi-center clinical trials failed to show non-inferiority of de-escalation strategies on a population basis, highlighting the need to select low-risk patients likely to respond to de-intensified treatments. In contrast, there is a substantial proportion of patients who develop recurrent disease despite aggressive therapy. This supports that HPV + OPSCC is not a homogeneous disease, but comprises distinct subtypes with clinical and biological variations. The overall goal for this review is to identify biomarkers for HPV + OPSCC that may be relevant for patient stratification for personalized treatment. We discuss HPV + OPSCC as a heterogeneous disease from multifaceted perspectives including clinical behavior, tumor morphology, and molecular phenotype. Molecular profiling from bulk tumors as well as single-cell sequencing data are discussed as potential driving factors of heterogeneity between tumor subgroups. Finally, we evaluate key challenges that may impede in-depth investigations of HPV + OPSCC heterogeneity and outline potential future directions, including a section on racial and ethnic differences.

The 3D's of Neural Phenotypes in Oral Cancer: Distance, Diameter, and Density

Squamous cell carcinoma of the oral cavity (OSCC) is the most common type of head and neck cancer; survival is poor, and response to treatment varies. Metastasis or recurrence in the regional lymph nodes is associated with poor survival. Consequently, overt or occult spread to the lymph nodes is used to identify patients who will receive adjuvant radiation therapy. Perineural invasion and the diameter of nerves exhibiting perineural invasion have also been suggested to be of prognostic significance. The explosion of interest in cancer neuroscience in the last two decades has led to novel biological insights into interactions between nerves and tumor cells. However, the criteria for defining perineural invasion have lagged behind current knowledge. It is important to re-evaluate the concept of perineural invasion and identify other neural phenotypes in OSCC that can impact treatment selection and prognosis. In addition to perineural invasion, neural phenotypes that are of potential relevance to tumor progression include nerve-tumor distance, nerve diameter, and nerve density. This manuscript discusses the translational significance of recent mechanistic studies on the progression of oral cancer.

Neurons as stromal drivers of nervous system cancer formation and progression

Similar to their pivotal roles in nervous system development, neurons have emerged as critical regulators of cancer initiation, maintenance, and progression. Focusing on nervous system tumors, we describe the normal relationships between neurons and other cell types relevant to normal nerve function, and discuss how disruptions of these interactions promote tumor evolution, focusing on electrical (gap junctions) and chemical (synaptic) coupling, as well as the establishment of new paracrine relationships. We also review how neuron-tumor communication contributes to some of the complications of cancer, including neuropathy, chemobrain, seizures, and pain. Finally, we consider the implications of cancer neuroscience in establishing risk for tumor penetrance and in the design of future anti-tumoral treatments.

Adjuvant Radiotherapy in Surgically Treated HPV-Positive Oropharyngeal Carcinoma with Adverse Pathological Features

Purpose: HPV-positive oropharyngeal carcinoma (HPV-OPC) is increasingly treated with primary surgery. The National Comprehensive Cancer Network (NCCN) recommends adjuvant therapy for surgically treated HPV-OPC displaying adverse pathological features (AF). We evaluated adjuvant radiotherapy patterns and outcomes in surgically treated AF-positive HPV-OPC (AF-HPV-OPC). Methods: The National Cancer Database was interrogated for patients ≥ 18 years with early-stage HPV-OPC from 2010 to 2017 who underwent definitive resection. Patients that had an NCCN-defined AF indication for adjuvant radiotherapy were assessed, including positive surgical margins (PSM), extranodal extension (ENE), lymphovascular invasion, and level 4/5 cervical lymph nodes. Overall survival (OS) was evaluated using Cox proportional hazards models and Kaplan−Meier analysis in whole and propensity score matched (PM) cohorts. Results: Of 15,036 patients meeting inclusion criteria, 55.7% were positive for at least one AF. Presence of any AF was associated with worse OS (hazard ratio (HR) = 1.56, p < 0.001). In isolation, each AF was associated with worse OS. On PM analysis, insurance status, T2 category, Charlson-Deyo comorbidity score, ENE (HR = 1.81, p < 0.001), and PSM (HR = 1.58, p = 0.002) were associated with worse OS. Median 3-year OS was 92.0% among AF-HPV-OPC patients undergoing adjuvant radiotherapy and 84.2% for those who did not receive adjuvant radiotherapy (p < 0.001, n = 1678). The overall rate of patients with AF-HPV-OPC who did not receive adjuvant radiotherapy was 13% and increased from 10% in 2010 to 17% in 2017 (ptrend = 0.007). Conclusions: In patients with AF-HPV-OPC, adjuvant radiotherapy is associated with improved survival. In the era of de-escalation therapy for HPV-OPC, our findings demonstrate the persistent prognostic benefit of post-operative radiotherapy in the setting of commonly identified adverse features. Ongoing clinical trials will better elucidate optimized patient selection for de-escalated therapy.

HPV-associated oropharyngeal cancer: epidemiology, molecular biology and clinical management

Human papillomavirus (HPV)-positive (HPV⁺) oropharyngeal squamous cell carcinoma (OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the UICC/AJCC staging system separates HPV⁺ OPSCC from its HPV-negative (HPV⁻) counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment de-intensification as a means to improve quality of life while maintaining acceptable survival outcomes. In addition, owing to the distinct biology of HPV⁺ OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage owing to a lack of symptoms in the early stages; therefore, a need exists to identify and validate possible diagnostic biomarkers to aid in earlier detection. In this Review, we provide a summary of the epidemiology, molecular biology and clinical management of HPV⁺ OPSCC in an effort to highlight important advances in the field. Ultimately, a need exists for improved understanding of the molecular basis and clinical course of this disease to guide efforts towards early detection and precision care, and to improve patient outcomes.

The incidence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is increasing rapidly in most developed countries. In this Review, the authors provide an overview of the epidemiology, molecular biology and treatment of HPV-positive OPSCC, including discussions of the role of treatment de-escalation and emerging novel therapies.

The incidence of human papillomavirus-associated oropharyngeal cancer (HPV⁺ OPSCC) is expected to continue to rise over the coming decades until the benefits of gender-neutral prophylactic HPV vaccination begin to become manifest.

The incidence of HPV⁺ OPSCC appears to be highest in high-income countries, although more epidemiological data are needed from low- and middle-income countries, in which HPV vaccination coverage remains low.

The substantially better prognosis of patients with HPV⁺ OPSCC compared to those with HPV^– OPSCC has been recognized in the American Joint Committee on Cancer TNM8 staging guidelines, which recommend stratification by HPV status to improve staging.

The molecular biology and genomic features of HPV⁺ OPSCC are similar to those of other HPV-associated malignancies, with HPV oncogenes (E6 and E7) acting as key drivers of pathogenesis.

Treatment de-intensification is being pursued in clinical trials, although identifying the ~15% of patients with HPV⁺ OPSCC who have recurrent disease, and who therefore require more intensive treatment, remains a key challenge.

Development and Assessment of a Novel Composite Pathologic Risk Stratification for Surgically Resected Human Papillomavirus-Associated Oropharyngeal Cancer

Importance

Human papillomavirus-associated (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is a distinct form of head and neck squamous cell carcinoma (HNSCC) with its own American Joint Committee on Cancer staging system. However, pathologic risk stratification for HPV+ OPSCC largely remains based on the experience with HPV-unassociated HNSCC.

Objective

To compare the survival discrimination of traditional pathologic risk stratification for both HPV+ OPSCC and HPV-unassociated HNSCC and derive a novel pathologic risk stratification system for HPV+ OPSCC with improved survival discrimination.

Design, Setting, and Participants

In this retrospective cohort study, we used the National Cancer Database to identify 15 324 patients diagnosed with nonmetastatic HNSCC between January 1, 2010, and December 31, 2013, who were treated with upfront surgery and neck dissection. We compared traditional pathologic risk stratification for HPV+ OPSCC and HPV-unassociated HNSCC and then derived a novel pathologic risk stratification system. Analyses were performed from July 1, 2018, to January 31, 2019.

Exposures

Definitive primary surgical resection and neck dissection.

Main Outcomes and Measures

Survival discrimination of pathologic risk stratification systems measured with concordance indices.

Results

This retrospective cohort study included 15 324 patients (10 779 men and 4545 women; mean [SD] age, 59.9 [11.8] years) with surgically treated nonmetastatic HNSCC. Separation of survival curves for HPV-unassociated HNSCC using traditional pathologic risk stratification (5-year overall survival for the low-, intermediate-, and high-risk groups) were 76.2%, 54.5%, and 40.9%, respectively. Separation curves for HPV+ OPSCC were 93.2%, 88.9%, and 83.7%, respectively. Human papillomavirus-unassociated HNSCC had a concordance index of 0.68, whereas HPV+ OPSCC had a concordance index of 0.58. A novel risk stratification system for HPV+ OPSCC that more closely fits actual survival rates for HPV+ OPSCC was derived. The system incorporated the composite number of pathologic adverse features. This composite risk stratification system was associated with an improved concordance index of 0.67 for HPV+ OPSCC. Adjuvant treatment with radiation was not associated with improved survival for patients categorized as low risk according to the new risk stratification system, but this treatment was associated with improved survival for patients in the intermediate- and high-risk groups.

Conclusions and Relevance

Traditional pathologic risk stratification shows poor survival discrimination for HPV+ OPSCC and classifies many patients with an excellent prognosis as high risk. We derived a novel composite pathologic risk stratification system for HPV+ OPSCC that may be associated with improved survival discrimination.

TORS elective lingual tonsillectomy has less acute morbidity than therapeutic base of tongue TORS

OBJECTIVE

To determine the impact of diagnostic TORS lingual tonsillectomy (DTLT) on objective swallowing measures for carcinoma of unknown primary (CUP).

METHODS

Between 10/2016-1/2020, 27 patients with p16+ squamous cell carcinoma (SCC) level 2a nodal disease underwent DTLT and ipsilateral neck dissection for CUP. No patient had a history of cutaneous SCC. Patients participated in Modified Barium Swallow (MBS) three weeks post-TORS, which were then compared to those from a contemporaneous cohort of 40 patients with clinically-identified p16+ base of tongue (BOT) primary tumors. DIGEST scores were retrospectively calculated. Univariate and multivariate analysis performed, stratified by BOT glossectomy (n = 40) versus lingual tonsillectomy for CUP (n = 27). Radiation to the resected primary or potential primary sources was omitted if margins were ≥3 mm or if no primary identified.

RESULTS

Twenty-seven consecutive patients with clinical stage cT0N1 HPV-associated OPSCC had a BOT primary pathologically identified in 18/27 (67%). Univariate analysis of functional swallow assessment on MBSImP correlated with improved post-TORS DIGEST scores for CUP. On multivariate analysis (MVA) DIGEST safety scores were improved for CUP than cT1 BOT glossectomy [Odds Ratio (OR) 0.28, p = 0.038]. MVA on matched pT1 CUP (n = 27) vs. pT1 BOT (n = 19), OR of moderate/severe dysphagia for CUP was 0.54 [0.12-2.38, p = 0.417] for DIGEST safety scores and 0.27 [0.06-1.18, p = 0.082] for DIGEST efficiency scores. Moderate/severe dysphagia as determined by DIGEST overall scores for CUP compared to cT1 and pT1 yielded an OR of 0.39 (p = 0.081) and 0.42 (p = 0.195), respectively. Twenty-six total patients received adjuvant RT, and 18 (11 with ≥3 mm margins, 9 with negative specimens) were spared intentional RT to the oropharynx. Median follow-up was 22.6 months with 100% PFS.

CONCLUSIONS

Patients undergoing DTLT for CUP demonstrated acute swallow defecits in the post-operative setting. A comparison of long-term functional results between DTLT and elective irradiation of the primary site should be studied.

LEVEL OF EVIDENCE

Level III.

Rate of locoregional recurrence among patients with oropharyngeal squamous cell carcinoma with known HPV status: a systematic review

Background: We aimed to review systematically the literature on locoregional recurrence rates in patients with HPV-positive and -negative oropharyngeal squamous cell carcinoma (OPSCC).Methods: PubMed and Embase databases were systematically searched using key words such as human papillomavirus, oropharyngeal squamous cell carcinoma with local, regional, and locoregional recurrence.Results: Nine studies (2974 patients with known HPV-status, 59% HPV-positive) were included. Among the HPV-positive and -negative patients, 69% and 58% had lymph node metastasis at diagnosis. At a median time to recurrence ranging from 8.4 to 13.2 months among the included studies, we found that a weighted average of 9% and 26% for HPV-positive and -negative patients experienced locoregional recurrence. Overall, the median follow-up time ranged from 21 to 83 months among the included studies.Conclusion: Recurrence rates for HPV-positive and -negative OPSCC patients were 9% and 26%, respectively, equating to an almost three times higher rate of locoregional recurrence among HPV-negative patients compared to HPV-positive patients.

Predictors of occult lymph node metastases in lip cancer

OBJECTIVE

The incidence of lymph node metastases (LNM) in squamous cell carcinoma of the lip is modest (8%), making it challenging to identify patients that may benefit from elective pathologic staging evaluation of the neck. We evaluated predictors of LNM in patients with lip cancer in order to potentially refine selection of patients for pathologic staging evaluation of the neck.

STUDY DESIGN

Retrospective cohort study.

SUBJECTS

Clinically N0 patients with squamous cell carcinoma of the lip that underwent definitive surgical resection and pathologic evaluation of lymph node metastases in the National Cancer Data Base from 2006 to 2013.

METHODS

Multivariable binomial logistic-regression was used to assess the relationship between occult pathologic lymph node metastasis and potential preoperative predictors including; patient demographics, T-stage, location, and pathologic details.

RESULTS

Among 786 patients the overall rate of LNM was 12.1%. Patients were more likely to have LNM with T2 (odds ratio (OR) 2.05; (95% confidence interval (CI) 1.19-3.54) or T3-4 (OR 2.36; CI 1.32-4.22) moderately differentiated (OR 2.65; CI 1.30-5.38) or poorly differentiated (OR 4.37; CI 1.97-9.71), or involvement of the mucosal surface (OR 1.82; CI 1.09-3.03). We created a prediction model based on proportional odd ratios from multivariant binomial logistic-regression analysis from statistically significant factors; incorporating T2-4, moderate/poorly differentiated, or mucosal site.

CONCLUSION

Our prediction model found that patients with two or more risk factors were the best candidates for elective pathologic nodal evaluation.

Widespread expression of Sonic hedgehog (Shh) and Nrf2 in patients treated with cisplatin predicts outcome in resected tumors and are potential therapeutic targets for HPV-negative head and neck cancer

Background:

Sonic hedgehog (Shh) and Nrf2 play a critical role in chemotherapeutic resistance. These two genes have been found to be dysregulated in head and neck squamous cell carcinomas (HNSCC). The purpose of this study was to analyze the expression, function and clinical prognostic relationship of Shh and Nrf2 in HNSCC in the context of therapeutic resistance and cancer stem cells (CSCs).

Methods:

We analyzed a cohort of patients with HNSCC to identify potential therapeutic biomarkers correlating with overall survival (OS) as well as disease-free survival (DFS) from our own data and validated these results using The Cancer Genome Atlas dataset. Expression of Shh and Nrf2 was knocked down by siRNA and cell growth, sphere growth and chemotherapeutic resistance were evaluated.

Results:

Widespread abundant expression of Shh and Nrf2 proteins were associated with shorter OS and DFS. The combination of Shh and Nrf2 expression levels was found to be a significant predictor of patient DFS. The tumor stromal index was correlated with Shh expression and inversely associated with shorter OS and DFS. Inhibition of Shh by siRNA or cyclopamine resulted in the attenuation of resistant CSC self-renewal, invasion, clonogenic growth and re-sensitization to the chemotherapeutic agents. Concomitant upregulation of Shh and Nrf2 proved to be an independent predictor of poor OS and DFS in patients with HNSCC.

Conclusions:

These findings suggest that Shh and Nrf2 could serve as therapeutic targets as well as promising dual prognostic therapeutic biomarkers for HNSCC.

Evaluation of a Touchless Angiography Suite Computer Controller for Neuroendovascular Procedures

BACKGROUND AND PURPOSE

The GestSure system is an Food and Drugs Administration (FDA)-registered depth-sensing infrared device initially developed for touchless image navigation during open surgery. The goal of this study was to explore the feasibility of this technology with medical students, residents, fellows and staff neurointerventionalists, using cases of intracranial aneurysm coiling.

MATERIAL AND METHODS

This was a prospective cohort study of operative performance using standard keyboard and mouse against a gestural interface. A total of four medical students, six residents, six fellows and five staff neurointerventionalists were involved in the training and subsequent testing. Training involved description and demonstration of a set of gestures optimized for 3D software functions. Cases were selected from the set of patients who underwent endovascular aneurysm coiling at the Toronto Western Hospital.

RESULTS AND CONCLUSION

For the overall group 15/21 (71.4%) individuals learned the left anterior oblique 30 degrees (LAO30) task within 20 cases, 17/21 (80.9%) learned the aneurysm neck task within 20 cases, 16/21 (76.2%) learned the parent vessel task and 14/21 (66%) learned the neck and parent vessel (anatomical) tasks. Staff were more consistent (i.e. smallest standard deviation) amongst the groups compared to medical students and residents; however, it was noted that a significant learning effect was observed in participants across every level of medical and angiographic expertise. Touchless angiography suite control with a gestural interface is feasible for the manipulation of angiographic images for neuroendovascular procedures. Learning to use the system was rapid across any level of medical training but greatest for staff neurointerventionalists.

Perineural invasion of cancer: a complex crosstalk between cells and molecules in the perineural niche

Perineural invasion (PNI) can be found in a variety of malignant tumors. It is a sign of tumor metastasis and invasion and portends the poor prognosis of patients. The pathological description and clinical significance of PNI are clearly understood, but exploration of the underlying molecular mechanism is ongoing. It was previously thought that the low-resistance channel in the anatomic region led to the occurrence of PNI. However, with rapid development of precision medicine and molecular biology, we have gradually realized that the occurrence of PNI is not the result of a single factor. The latest study suggests that PNI of cancer is a continuous and multistep process. A specific peripheral microenvironment, also called the perineural niche, is formed by neural cells, supporting cells, recruited inflammatory cells, altered extracellular matrix, blood vessels, and immune components in the background of carcinoma. Various soluble signaling molecules and their receptors comprise a complex signal network, which achieves the interaction between nerve and tumor. Nerve cells and tumor cells can interact directly or through the opening and closing of the signal transduction pathways and/or the recognition and response of the ligands and receptors. The information is transferred to the targets accurately and effectively, leading to the specific interactions between the nerve cells and the malignant tumor cells. PNI occurs through changes in nerve cells and supporting cells in the background of cancer; change and migration of the perineural matrix; enhancement of the viability, mobility, and invasiveness of the tumor cells; injury and regeneration of nerve cells; interaction, chemotactic movement, contact, and adherence of the nerve cells and the tumor cells; escape from autophagy, apoptosis, and immunological surveillance of tumor cells; and so on. Certainly, exploring the mechanism of PNI clearly has great significance for blocking tumor progression and improving patient survival. The current review aims to elucidate the cellular and molecular mechanisms of PNI, which may help us find a strategy for improving the prognosis of malignant tumors.

Primary surgery for human papillomavirus-associated oropharyngeal cancer: Survival outcomes with or without adjuvant treatment

OBJECTIVES

Human papillomavirus-associated (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is a unique form of head and neck cancer with improved prognosis. We assessed survival for stage I patients with low- or intermediate-risk pathologic features with surgery alone compared with surgery with adjuvant radiation (RT) or chemoradiation (CRT).

MATERIALS AND METHODS

We identified patients with stage I HPV+ OPSCC (after restaging with 8th edition staging system) treated with surgery alone, adjuvant RT or CRT in the National Cancer Data Base from 2010 to 2013. We compared survival for low-risk patients (≤1 metastatic lymph nodes with no adverse features) and intermediate-risk patients (2-4 metastatic lymph nodes, microscopic extranodal extension (ENE) or lymphovascular invasion).

RESULTS

We examined 1677 patients with median follow-up of 43.9 months. In the intermediate-risk group, 4-year overall survival was 94.0% with surgery alone, 91.5% with adjuvant RT and 92.0% with adjuvant CRT (p = 0.72). There were similar rates of overall survival in the low-risk group. In multivariable models accounting for clinicopathologic differences the dose of adjuvant RT was not associated with mortality. On Cox proportional hazard modeling, adjuvant RT (HR 0.94; CI 0.43-2.08) or CRT (HR 0.96; CI 0.45-2.11) did not significantly improved survival compared with surgery alone in the intermediate-risk group (reference). Similar results were seen in the low-risk group. The composite number of pathologic risk features significantly improved risk stratification.

CONCLUSION

We provide observational evidence that adjuvant RT or CRT does not provide a survival benefit for stage I HPV+ OPSCC with low- or intermediate-risk pathologic features.

Mouse model of postsurgical primary tumor recurrence and regional lymph node metastasis progression in HPV-related head and neck cancer

HPV-positive head and neck squamous cell carcinoma (HNSCC) is increasingly frequent. Management is particularly debated in the case of postsurgical high-risk features, that is, positive surgical margins and extracapsular spread (ECS). In this increasingly complex emerging framework of HNSCC treatment, representative preclinical models are needed to support future clinical trials and advances in personalized medicine. Here, we present an immunocompetent mouse model based on the implantation of mouse tonsil epithelial HPV16-E6/E7-expressing cancer cells into the submental region of the floor-of-the-mouth. Primary tumors were found to replicate the patterns of human HNSCC local invasion and lymphatic dissemination. To study disease progression after surgery, tumors were removed likely leaving behind residual disease. Surgical resection of tumors was followed by a high rate of local recurrences (>90%) within the first 2-3 weeks. While only 50% of mice had lymph node metastases (LNM) at time of primary tumor excision, all mice with recurrent tumors showed evidence of LNM. To study the consecutive steps of LNM progression and distant metastasis development, LNs from tumor-bearing mice were transplanted into naïve recipient mice. Using this approach, transplanted LNs were found to recapitulate all stages and relevant histological features of regional metastasis progression, including ECS and metastatic spread to the lungs. Altogether, we have developed an immunocompetent HPV-positive HNSCC mouse model of postsurgical local recurrence and regional and distant metastasis progression suitable for preclinical studies.