The role of total parotidectomy in high-grade parotid malignancy: A multisurgeon retrospective review.

PURPOSE: Determine rates of intra-parotid and neck nodal metastasis, identify risk factors for recurrence, and report outcomes in patients with primary high-grade parotid malignancy who undergo total parotidectomy and neck dissection. MATERIALS & METHODS: Retrospective review of patients undergoing total parotidectomy and neck dissection for high-grade parotid malignancy between 2005 and 2015. The presence and number of parotid lymph nodes, superficial and deep, as well as cervical lymph nodes involved with metastatic disease were assessed. Risk factors associated with metastatic spread to the parotid deep lobe were identified and recurrence rates reported. RESULTS: 75 patients with median follow-up time of 47 months. 35 patients (46.7%) had parotid lymph node metastasis. Seven patients (9.3%) had deep lobe nodal metastasis without metastasis to the superficial lobe nodes. Nine patients (12%) had positive intra-parotid nodes without positive cervical nodes. Cervical nodal disease was identified in 49.3% patients (37/75). Local, parotid-bed recurrence rate was 5.3% (4/75). Regional lymph node recurrence rate was also 5.3% (4/75). Rate of distant metastasis was 30.6% (23/75). The overall disease free survival rate for all patients at 2 and 5 years were 71% and 60% respectively. CONCLUSION: Parotid lymph node metastasis occurred at a similar rate to cervical lymph node metastasis (46.7% and 49.3%, respectively). Deep lobe parotid nodal metastasis occurred in nearly a quarter of patients and can occur without superficial parotid nodal metastasis. Rate of recurrence in the parotid bed, which may represent local or regional recurrence, was similar to regional cervical lymph node recurrence. Total parotidectomy and neck dissection should be considered high-grade parotid malignancy regardless of clinical nodal status.

Heterogeneous Binding and Central Nervous System Distribution of the Multitargeted Kinase Inhibitor Ponatinib Restrict Orthotopic Efficacy in a Patient-Derived Xenograft Model of Glioblastoma.

This study investigated how differences in drug distribution and free fraction at different tumor and tissue sites influence the efficacy of the multikinase inhibitor ponatinib in a patient-derived xenograft model of glioblastoma (GBM). Efficacy studies in GBM6 flank (heterotopic) and intracranial (orthotopic) models showed that ponatinib is effective in the flank but not in the intracranial model, despite a relatively high brain-to-plasma ratio. In vitro binding studies indicated that flank tumor had a higher free (unbound) drug fraction than normal brain. The total and free drug concentrations, along with the tissue-to-plasma ratio (Kp) and its unbound derivative (Kp,uu), were consistently higher in the flank tumor than the normal brain at 1 and 6 hours after a single dose in GBM6 flank xenografts. In the orthotopic xenografts, the intracranial tumor core displayed higher Kp and Kp,uu values compared with the brain-around-tumor (BAT). The free fractions and the total drug concentrations, hence free drug concentrations, were consistently higher in the core than in the BAT at 1 and 6 hours postdose. The delivery disadvantages in the brain and BAT were further evidenced by the low total drug concentrations in these areas that did not consistently exceed the in vitro cytotoxic concentration (IC50). Taken together, the regional differences in free drug exposure across the intracranial tumor may be responsible for compromising efficacy of ponatinib in orthotopic GBM6.

Factors Influencing the Central Nervous System Distribution of a Novel Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Inhibitor GSK2126458: Implications for Overcoming Resistance with Combination Therapy for Melanoma Brain Metastases.

Small molecule inhibitors targeting the mitogen-activated protein kinase pathway (Braf/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase) have had success in extending survival for patients with metastatic melanoma. Unfortunately, resistance may occur via cross-activation of alternate signaling pathways. One approach to overcome resistance is to simultaneously target the phosphoinositide 3-kinase/mammalian target of rapamycin signaling pathway. Recent reports have shown that GSK2126458 [2,4-difluoro-N-(2-methoxy-5-(4-(pyridazin-4-yl)quinolin-6-yl)pyridin-3-yl) benzenesulfonamide], a dual phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor, can overcome acquired resistance to Braf and mitogen-activated protein kinase kinase inhibitors in vitro. These resistance mechanisms may be especially important in melanoma brain metastases because of limited drug delivery across the blood-brain barrier. The purpose of this study was to investigate factors that influence the brain distribution of GSK2126458 and to examine the efficacy of GSK2126458 in a novel patient-derived melanoma xenograft (PDX) model. Both in vitro and in vivo studies indicate that GSK2126458 is a substrate for P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp), two dominant active efflux transporters in the blood-brain barrier. The steady-state brain distribution of GSK2126458 was 8-fold higher in the P-gp/Bcrp knockout mice compared with the wild type. We also observed that when simultaneously infused to steady state, GSK212658, dabrafenib, and trametinib, a rational combination to overcome mitogen-activated protein kinase inhibitor resistance, all had limited brain distribution. Coadministration of elacridar, a P-gp/Bcrp inhibitor, increased the brain distribution of GSK2126458 by approximately 7-fold in wild-type mice. In the PDX model, GSK2126458 showed efficacy in flank tumors but was ineffective in intracranial melanoma. These results show that P-gp and Bcrp are involved in limiting the brain distribution of GSK2126458 and provide a rationale for the lack of efficacy of GSK2126458 in the orthotopic PDX model.

Integrative analysis of H&E and IHC identifies prognostic immune subtypes in HPV related oropharyngeal cancer.

BACKGROUND: Deep learning techniques excel at identifying tumor-infiltrating lymphocytes (TILs) and immune phenotypes in hematoxylin and eosin (H&E)-stained slides. However, their ability to elucidate detailed functional characteristics of diverse cellular phenotypes within tumor immune microenvironment (TME) is limited. We aimed to enhance our understanding of cellular composition and functional characteristics across TME regions and improve patient stratification by integrating H&E with adjacent immunohistochemistry (IHC) images. METHODS: A retrospective study was conducted on patients with Human Papillomavirus-positive oropharyngeal squamous cell carcinoma (OPSCC). Using paired H&E and IHC slides for 11 proteins, a deep learning pipeline was used to quantify tumor, stroma, and TILs in the TME. Patients were classified into immune inflamed (IN), immune excluded (IE), or immune desert (ID) phenotypes. By registering the IHC and H&E slides, we integrated IHC data to capture protein expression in the corresponding tumor regions. We further stratified patients into specific immune subtypes, such as IN, with increased or reduced CD8+ cells, based on the abundance of these proteins. This characterization provided functional insight into the H&E-based subtypes. RESULTS: Analysis of 88 primary tumors and 70 involved lymph node tissue images reveals an improved prognosis in patients classified as IN in primary tumors with high CD8 and low CD163 expression (p = 0.007). Multivariate Cox regression analysis confirms a significantly better prognosis for these subtypes. CONCLUSIONS: Integrating H&E and IHC data enhances the functional characterization of immune phenotypes of the TME with biological interpretability, and improves patient stratification in HPV( + ) OPSCC.

In this study, we investigated whether differences in the immune cell population surrounding head and neck cancers impact disease progression. We used advanced computer programs to analyze tissue samples from tumors and nearby lymph nodes, a part of the immune system. These tumor and lymph node samples were stained to show the structure of the tissue and to identify the different types of immune cells present. We grouped patients into different categories based on differences in their immune cells. We found that patients with certain patterns of immune cells tended to have better outcomes. This method could help doctors predict how well patients will respond to treatments.

Advancing head and neck cancer management: Unveiling the diagnostic and therapeutic potentials of molecular profiling.

BACKGROUND: Head and neck cancers (HNC) present diagnostic challenges due to multifocal disease manifestations, posing difficulties in distinguishing between metastatic disease and second primary malignancies (SPM). This complexity underscores the need for advanced diagnostic approaches. Emerging technologies, such as next-generation sequencing (NGS) and molecular classifier assays, show promise in providing precise insights into the diverse etiologies of HNC. METHOD: In this article, we employed NGS and molecular classifier assays to delve into three distinct clinical cases. The objective was to showcase the instrumental role of these technologies in facilitating accurate diagnoses and differentiating between metastatic disease and SPM in HNC cases. RESULTS: The results of this series highlight the effectiveness of NGS and molecular classifier assays in enhancing diagnostic accuracy for HNC and contributing to the precise differentiation of disease etiologies. The utilization of these advanced technologies proved instrumental in avoiding unnecessary interventions and paved the way for more targeted and effective treatment strategies. CONCLUSION: Our findings underscore the necessity of incorporating advanced molecular testing technologies into the diagnostic and therapeutic approaches for HNC, thereby championing a more nuanced and effective approach to managing these complex cases.

Elective Irradiation of Retropharyngeal Lymph Nodes as an Indication for Adjuvant Radiation Therapy After Transoral Surgery for Tonsil Cancer.

Treatment of squamous cell carcinoma of the tonsil involves primary radiation therapy (RT) or surgical resection. Historically, if RT was the primary or adjuvant treatment modality, most of the bilateral retropharyngeal lymph nodes (RPLNs) were treated electively with a therapeutic dose for subclinical disease, regardless of whether radiographically pathologic lymph nodes were seen on initial diagnostic imaging. De-escalation strategies include the incorporation of transoral surgery with the goal to either eliminate or reduce the dose of adjuvant RT or chemotherapy. Transoral surgery does not include elective removal of the RPLNs, and no guideline or outcome paper recommends adjuvant RT specifically to electively treat RPLNs. In this Topic Discussion, we discuss pertinent literature and suggest management decisions. The management decisions discussed in this Topic Discussion pertain to only tonsillar primaries and not those of the soft palate or base of the tongue.

Impact of radiation dose distribution on nutritional supplementation needs in head and neck cancer radiotherapy: a voxel-based machine learning approach.

Objectives: To investigate the relationship between nutritional supplementation and radiation dose to the pharyngeal constrictor muscles and larynx for head and neck (HN) cancer patients undergoing radiotherapy. Methods: We retrospectively analyzed radiotherapy (RT) dose for 231 HN cancer patients, focusing on the pharyngeal constrictors and larynx. We defined nutritional supplementation as feeding tube utilization or >10% weight loss from baseline within 90 days after radiotherapy completion. Using deformable image registration (DIR), we mapped each patient's anatomical structures to a reference coordinate system, and corresponding deformations were applied to dose matrices. Voxel doses were utilized as features for ridge logistic regression models, optimized through 5-fold cross-validation. Model performance was assessed with area under the curve of a receiver operating curve (AUC) and F1 score. We built and compared models using 1) pharyngeal constrictor voxels, 2) larynx voxels, 3) clinical factors and mean regional dose metrics, and 4) clinical factors and dose-volume histogram metrics. Test set AUCs were compared among the models, and feature importance was evaluated. Results: DIR of the pharyngeal constrictors and larynx yielded mean Dice coefficients of 0.80 and 0.84, respectively. Pharyngeal constrictors voxels and larynx voxel models had AUC of 0.88 and 0.82, respectively. Voxel-based dose modeling identified the superior to middle regions of the pharyngeal constrictors and the superior region of larynx as most predictive of feeding tube use/weight loss. Univariate analysis found treatment setting, treatment laterality, chemotherapy, baseline dysphagia, weight, and socioeconomic status predictive of outcome. An aggregated model using mean doses of pharyngeal constrictors and larynx subregions had an AUC of 0.87 and the model using conventional DVH metrics had an AUC of 0.85 with p-value of 0.04. Feature importance calculations from the regional dose model indicated that mean doses to the superior-middle pharyngeal constrictor muscles followed by mean dose to the superior larynx were most predictive of nutritional supplementation. Conclusions: Machine learning modeling of voxel-level doses enables identification of subregions within organs that correlate with toxicity. For HN radiotherapy, doses to the superior-middle pharyngeal constrictors are most predictive of feeding tube use/weight loss followed by the doses to superior portion of the larynx.

Radiation Dose Sensitivity of Subregions of the Larynx to Patient-Reported Swallowing Outcomes.

Purpose: To assess any correlation between swallowing dysfunction and radiation dose to 5 subregions of the larynx. Methods and Materials: A cohort of 136 patients with head and neck cancer, treated with either photon or proton radiation therapy, was assessed using an endpoint of patient-reported swallowing scores, evaluated with the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-H&N35 survey, within 1 month after treatment. Five subregions of the larynx were contoured, and dosimetric metrics were extracted for each subregion as well as the total larynx. Univariate and multivariate logistic regression statistical analyses were used to determine statistical correlation with the dose metrics and clinical variables. Univariate regression models were statistically compared using a non-nested model test. Results: Under univariate analysis, unilateral versus bilateral nodal irradiation (P = .004), concurrent chemotherapy (P = .007), and surgery (P = .015) were statistically significant predictors of poor swallowing score. Unilateral versus bilateral irradiation was statistically significant under multivariate analysis (P = .039). The epiglottis was the most predictive subregion of swallowing score, with a majority (21 of 25) of dosimetric variables being identified as statistically significant. The maximum dose to the epiglottis was the most significant dosimetric variable tested for poor swallowing score in both univariate (P = .003) and multivariate (P = .051) analyses. Comparison of univariate models indicated a general preference for epiglottic variables with the mean dose to the epiglottis being preferred at a statistically significant level in many cases. Conclusions: These results show the relatively increased sensitivity of the epiglottis compared with the rest of the larynx when considering patient-reported decrements in quality-of-life swallowing score and support both the inclusion of the epiglottis in standard larynx contours and the assessment of the epiglottis dose during plan evaluation. Our data suggest that keeping the mean and max doses to the epiglottis <20 to 37 Gy and <53 to 60 Gy, respectively, will reduce swallowing difficulties.

Cancer in Patients With Incidental Asymmetric Oropharynx Positron Emission Tomography Uptake.

Importance: Asymmetric oropharynx uptake on positron emission tomography (PET)/computed tomography (CT) is a common incidental finding and often prompts otolaryngology referral to rule out malignancy; however, the true risk of malignancy based on this finding is unknown. Objective: To identify the incidence of oropharynx cancer in patients with incidental asymmetric oropharynx PET uptake. Design, Setting, and Participants: In this retrospective cohort study, patients 18 years and older undergoing PET/CT scans at Mayo Clinic between January 2001 and December 2018 were included. Patients with a history or pretest suspicion of oropharynx cancer were excluded. Data were analyzed from March 2021 to December 2023. Exposure: Blinded radiologic review of imaging studies, including measurement of maximum standardized uptake values (SUVmax) of the ipsilateral side of concern and contralateral side. Retrospective medical record review for associated clinical data. Main Outcomes and Measures: The primary study outcome was the incidence of oropharynx cancer diagnosis in patients with asymmetric oropharynx PET uptake. The primary outcome was formulated before data collection. Results: Of the 1854 patients identified with asymmetric oropharynx PET uptake, 327 (17.6%) met inclusion criteria. Of these, 173 (52.9%) were male, and the median (range) age was 65.0 (24.8-90.7) years. The mean (SD) follow-up interval was 52.1 (43.4) months. A total of 18 of 327 patients (5.5%) were newly diagnosed with oropharynx cancer. The most common diagnosis was squamous cell carcinoma (n = 9), followed by lymphoma (n = 8), and sarcoma (n = 1). Patients with an incidental diagnosis of oropharynx cancer had higher mean (SD) ipsilateral SUVmax (8.7 [3.7] vs 5.3 [1.9]) and SUVmax ratio (3.0 [1.6] vs 1.6 [0.6]) compared with patients with normal examination findings. SUVmax ratio and difference were found to be good discriminators of oropharynx cancer, with areas under the receiver operating characteristic curve of 86.3% (95% CI, 76.4-94.6) and 85.8% (95% CI, 74.8-94.6), respectively. Patients with a new diagnosis of oropharynx cancer were more likely to have a corresponding CT abnormality than those with normal examination findings (6 of 18 [33%] vs 24 of 295 [8.1%]). Patients with concerning lesions on oropharynx palpation by an otolaryngology health care professional were significantly more likely to be diagnosed with oropharynx cancer compared with patients with normal examination findings (odds ratio, 28.4; 95% CI, 6.6-145.8). Conclusions and Relevance: In this cohort study, while incidental asymmetric oropharynx PET uptake was common, a new diagnosis of oropharynx cancer was not and potentially results in a large volume of unnecessary referrals and work-up. Using SUVmax ratio, SUVmax difference, and CT correlation may increase the benefit of referral. Patients with a palpable oropharynx lesion and asymmetric oropharynx PET uptake should undergo confirmatory biopsy.

Mean Oral Cavity Organ-at-Risk Dose Predicts Opioid Use and Hospitalization during Radiotherapy for Patients with Head and Neck Tumors.

BACKGROUND: Approximately 75% of all head and neck cancer patients are treated with radiotherapy (RT). RT to the oral cavity results in acute and late adverse events which can be severe and detrimental to a patient's quality of life and function. The purpose of this study was to explore associations between RT dose to a defined oral cavity organ-at-risk (OAR) avoidance structure, provider- and patient-reported outcomes (PROs), opioid use, and hospitalization. METHODS: This was a retrospective analysis of prospectively obtained outcomes using multivariable modeling. The study included 196 patients treated with RT involving the oral cavity for a head and neck tumor. A defined oral cavity OAR avoidance structure was used in all patients for RT treatment planning. Validated PROs were collected prospectively. Opioid use and hospitalization were abstracted electronically from medical records. RESULTS: Multivariable modeling revealed the mean dose to the oral cavity OAR was significantly associated with opioid use (p = 0.0082) and hospitalization (p = 0.0356) during and within 30 days of completing RT. CONCLUSIONS: The findings of this study may be valuable in RT treatment planning for patients with tumors of the head and neck region to reduce the need for opioid use and hospitalization during treatment.

Association Between Social Determinants of Health, Distance from Treatment Center, and Treatment Type with Outcomes in Human Papillomavirus Associated Oropharyngeal cancer.

OBJECTIVES: Social determinants of health (SDOH) can influence access to cancer care, clinical trials, and oncologic outcomes. We investigated the association between SDOH, distance from treatment center, and treatment type with outcomes in human papillomavirus associated oropharyngeal squamous cell carcinoma [HPV(+)OPSCC] patients treated at a tertiary care center. STUDY DESIGN: Retrospective review. METHODS: HPV(+)OPSCC patients treated surgically from 2006 to 2021 were selected from our departmental Oropharyngeal Cancer RedCap database. Demographic data, treatment, and oncologic outcomes were extracted. Distance was calculated in miles between the centroid of each patient zip code and our hospital zip code (zipdistance). RESULTS: 874 patients (89 % male; mean age: 58 years) were identified. Most patients (96 %) reported Non-Hispanic White as their primary race. 204 patients (23 %) had a high-school degree or less, 217 patients (25 %) reported some college education or a 2-year degree, 153 patients (18 %) completed a four-year college degree, and 155 patients (18 %) had post-graduate degrees. Relative to those with a high-school degree, patients with higher levels of education were more likely to live further away from our institution (p < 0.0001). Patients who received adjuvant radiation therapy elsewhere lived, on average, 104 miles further away than patients receiving radiation at our institution (Estimate 104.3, 95 % CI 14.2-194.4, p-value = 0.02). In univariable Cox PH models, oncologic outcomes did not significantly differ by zipdistance. CONCLUSIONS: Education level-and access to resources-varied proportionally to a patient's distance from our center. Patients travelling further distances for surgical management of OPSCC were more likely to pursue adjuvant radiation therapy at an outside institution. Distance traveled was not associated with oncologic outcomes. Breaking down barriers to currently excluded populations may improve access to clinical trials and improve oncologic outcomes for diverse patient populations.

Close Margins After Transoral Robotic Surgery for Human Papillomavirus-Positive Oropharyngeal Carcinoma: A Review of the Literature and Practical Recommendations.

The purpose of this article is to summarize the literature and practical recommendations from experienced centers for close margins after transoral robotic surgery for human papillomavirus-positive oropharyngeal carcinoma.

Impact of Tumor-Infiltrating Lymphocytes on Disease Progression in Human Papillomavirus-Related Oropharyngeal Carcinoma.

OBJECTIVE: We aim to explore the prognostic value of tumor-infiltrating lymphocytes (TILs) in the primary tumor and metastatic lymph nodes of patients with HPV(+)OPSCC. We hypothesize that TILS density at both sites is associated with disease-free survival in HPV(+)OPSCC. STUDY DESIGN: Matched case-control study among HPV(+)OPSCC patients who underwent intent-to-cure surgery. Cases developed locoregional or distant recurrence. Controls were matched based on age, sex, pathologic T, N, and overall stage, year of surgery, type of adjuvant treatment received, and the Adult Comorbidity Evaluation-27 (ACE-27) score. SETTING: Single tertiary care center, May 2007 to December 2016. METHODS: Tumoral TILs (tTILs) density was defined as % TILs; stromal TILs (sTILs) density was defined as absent/sparse or moderate/dense crowding. Associations between TILs and time to disease progression were assessed using Cox regression models. RESULTS: Forty-four case-control pairs (N = 88) were included: 42 (48%) AJCC pStage I, 39 (44%) pStage II, and 7 (8%) pStage III. tTILs density ≥10% (hazard ratio [HR] 0.41, 95% confidence interval [CI] 0.17-0.99, p = .048) and a moderate/dense sTILs density (HR 0.21, 95% CI 0.06-0.75, p = .016) in the primary tumor were significantly associated with decreased risk of progression. TILs density in the lymph node was associated with decreased risk of progression but did not reach statistical significance. The tTILs and sTILs density correlated strongly between the primary tumor and lymph node. Concordance between the pathologists' was moderate (60%-70%). CONCLUSIONS: In HPV(+)OPSCC, a higher density of tumoral and stromal TILs in the primary tumor and possibly the lymph node may predict a lower risk of disease progression.

Diagnostic Delay in Human Papillomavirus Negative Oropharyngeal Squamous Cell Carcinoma.

OBJECTIVE: Failure to recognize symptoms of non-human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV(-)OPSCC) at presentation can delay diagnosis and treatment. We aim to identify patient factors and provider practice patterns that delay presentation and care in HPV(-)OPSCC. METHODS: Retrospective review at a tertiary care center. Patients with HPV(-)OPSCC receiving treatment from 2006 to 2016. Patients were excluded if their date of symptom onset or diagnosis was unknown after thorough review of the electronic medical record or their tissue was not tested for HPV or p16. Clinical data, workup, and care timelines were abstracted. Univariate and multivariable linear regressions were performed to determine associations between patient and provider factors and delays in care. RESULTS: Of 70 included patients, 52 (74%) were male and mean age was 60.5 (SD = 9.0). Median time to diagnosis was 69 days (IQR = 32-127 days), with a median latency of 30 days (IQR = 12-61 days) from symptom onset to first presentation and 19.5 days (IQR = 4-46 days) from the first presentation to diagnosis. Most patients visited at least 2 providers (n = 52, 74%) before diagnosis. Evaluation by 3 or more providers prior to diagnosis was associated with significant delays in diagnosis of nearly a year (357.7 days, p < 0.001) and being treated or prescribed analgesia prior to diagnosis was significantly associated with delays in diagnosis (p = 0.004) on univariate regression analysis. CONCLUSIONS: Delays in care related to evaluations by multiple providers and misdiagnosis prolonged time to diagnosis in HPV(-)OPSCC. Improved patient and provider education is necessary to expedite the diagnosis of HPV(-)OPSCC. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:1394-1401, 2023.

Clinical aspects of spatially fractionated radiation therapy treatments.

PURPOSE: To provide clinical guidance for centers wishing to implement photon spatially fractionated radiation therapy (SFRT) treatments using either a brass grid or volumetric modulated arc therapy (VMAT) lattice approach. METHODS: We describe in detail processes which have been developed over the course of a 3-year period during which our institution treated over 240 SFRT cases. The importance of patient selection, along with aspects of simulation, treatment planning, quality assurance, and treatment delivery are discussed. Illustrative examples involving clinical cases are shown, and we discuss safety implications relevant to the heterogeneous dose distributions. RESULTS: SFRT can be an effective modality for tumors which are otherwise challenging to manage with conventional radiation therapy techniques or for patients who have limited treatment options. However, SFRT has several aspects which differ drastically from conventional radiation therapy treatments. Therefore, the successful implementation of an SFRT treatment program requires the multidisciplinary expertise and collaboration of physicians, physicists, dosimetrists, and radiation therapists. CONCLUSIONS: We have described methods for patient selection, simulation, treatment planning, quality assurance and delivery of clinical SFRT treatments which were built upon our experience treating a large patient population with both a brass grid and VMAT lattice approach. Preclinical research and patient trials aimed at understanding the mechanism of action are needed to elucidate which patients may benefit most from SFRT, and ultimately expand its use.

Adenoid cystic carcinoma of the head and neck: Patterns of recurrence and implications for intensity-modulated radiotherapy.

BACKGROUND: We seek to inform radiotherapy (RT) delivery for adenoid cystic carcinoma of the head and neck (ACC) by evaluating RT techniques and recurrence patterns. METHODS: We identified patients with ACC treated with curative-intent RT from 2005 to 2021. Imaging was reviewed to determine local recurrence (LR). RESULTS: Ninety-one patients were included. The 5-year LR risk was 12.2% (6.6-22.7). One patient each experienced a marginal and out-of-field recurrence. Patients receiving >60 Gy postoperatively had a 5-year LR risk of 0% compared to 10.7% (4.2-27.2) with ≤60 Gy. Those receiving 70 and <70 Gy definitively had a 5-year LR risk of 15.2% (2.5-91.6) and 33.3% (6.7-100.0), respectively. No patients had regional nodal failure. CONCLUSIONS: Modern, conformal RT for ACC results in low rates of LR. Doses >60 and 70 Gy may improve control in the postoperative and definitive settings, respectively. Elective nodal treatment can be omitted in well-selected patients.

Assessing the capacity of methylated DNA markers of cervical squamous cell carcinoma to discriminate oropharyngeal squamous cell carcinoma in human papillomavirus mediated disease.

OBJECTIVE: Early identification of human papillomavirus associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC) is challenging and novel biomarkers are needed. We hypothesized that a panel of methylated DNA markers (MDMs) found in HPV(+) cervical squamous cell carcinoma (CSCC) will have similar discrimination in HPV(+)OPSCC tissues. MATERIALS AND METHODS: Formalin-fixed, paraffin-embedded tissues were obtained from patients with primary HPV(+)OPSCC or HPV(+)CSCC; control tissues included normal oropharynx palatine tonsil (NOP) and cervix (NCS). Using a methylation-specific polymerase chain reaction, 21 previously validated cervical MDMs were evaluated on tissue-extracted DNA. Discrimination between case and control cervical and oropharynx tissue was assessed using area under the curve (AUC). RESULTS: 34 HPV(+)OPSCC, 36 HPV(+)CSCC, 26 NOP, and 24 NCS patients met inclusion criteria. Within HPV(+)CSCC, 18/21 (86%) of MDMs achieved an AUC ≥ 0.9 and all MDMs exhibited better than chance classifications relative to control cervical tissue (all p < 0.001). In contrast, within HPV(+)OPSCC only 5/21 (24%) MDMs achieved an AUC ≥ 0.90 but 19/21 (90%) exhibited better than chance classifications relative to control tonsil tissue (all p < 0.001). Overall, 13/21 MDMs had statistically significant lower AUCs in the oropharyngeal cohort compared to the cervical cohort, and only 1 MDM exhibited a statistically significant increase in AUC. CONCLUSIONS: Previously validated MDMs exhibited robust performance in independent HPV(+)CSCC patients. However, most of these MDMs exhibited higher discrimination for HPV(+)CSCC than for HPV(+)OPSCC. This suggests that each SCC subtype requires a unique set of MDMs for optimal discrimination. Future studies are necessary to establish an MDM panel for HPV(+)OPSCC.

Clinicopathologic Factors and Their Association with Outcomes of Salivary Duct Carcinoma: A Multicenter Experience.

Purpose: This series reports long-term clinical outcomes of patients with salivary duct carcinoma (SDC), which is associated with a poor prognosis. Methods and Materials: Eighty-nine patients with SDC were treated with curative intent from February 5, 1971, through September 15, 2018. Kaplan-Meier and competing risk analyses were used to estimate locoregional control, distant metastasis-free survival (DMFS), progression-free survival, and overall survival (OS). Cox regression analyses of disease and treatment characteristics were performed to discover predictors of locoregional control, DMFS, and OS. Results: Median follow-up was 44.1 months (range, 0.23-356.67). The median age at diagnosis was 66 years (interquartile range, 57-75). Curative surgery followed by adjuvant radiation therapy was performed in 73 patients (82%). Chemotherapy was delivered in 26 patients (29.2%). The 5-year local recurrence and distant metastasis rates were 27% and 44%, respectively, with death as a competing risk. Distant metastasis was associated with lymph node-positive disease (hazard ratio [HR], 3.16; 95% confidence interval [CI], 1.38-7.23; P = .006), stage IV disease (HR, 4.78; 95% CI, 1.14-20.11; P = .033), perineural invasion (HR, 4.56; 95% CI, 1.74-11.97; P = .002), and positive margins (HR, 9.06; 95% CI, 3.88-21.14; P < .001). Median OS was 4.84 years (95% CI, 3.54-7.02). The 5-year OS was 42%. Reduced OS was associated with lymphovascular space invasion (HR, 3.49; 95% CI, 1.2-10.1; P = .022), perineural invasion (HR, 2.05; 95% CI, 1.06-3.97; P = .033), positive margins (HR, 2.7; 95% CI, 1.3-5.6; P = .011), N2 disease (HR, 1.88; 95% CI, 1.03-3.43; P = .04), and N3 disease (HR, 11.76; 95% CI, 3.19-43.3; P < .001). Conclusions: In this single-institution, multicenter retrospective study, the 5-year survival was 42% in patients with SDC. Lymphovascular space invasion, lymph node involvement, and higher staging at diagnosis were associated with lower DMFS and OS.

A Prospective Study of Mucosal Sparing Radiation Therapy in Resected Oropharyngeal Cancer Patients.

PURPOSE: Our objective was to report the prospective results of mucosal sparing radiation therapy in human papillomavirus-related oropharyngeal squamous cell carcinoma. METHODS AND MATERIALS: From March 2016 through May 2019, patients were enrolled in this institutional review board-approved prospective cohort study at a multisite institution. Inclusion criteria included p16+ American Joint Committee on Cancer seventh edition pathologic T1 or T2, N1 to N3, and M0 oropharyngeal cancers. Proton therapy (PT) was delivered to at-risk nodal regions, excluding the primary mucosal site. Secondary to insurance denial for PT, intensity modulated radiation therapy (IMRT) was allowed. European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Head and Neck Module and Patient-Reported Outcomes Measurement Information System surveys (quality of life [QOL]) and modified barium swallowing impairment profiles (MBSImP) were obtained at baseline before radiation therapy, then 3 and 12 months after radiation therapy. Kaplan-Meier estimates were calculated for time-to-event clinical outcomes, and repeated measures mixed models were used to explore changes in QOL over time. A comparison of QOL and swallowing outcomes with standard-of-care treatment was analyzed. RESULTS: There were 61 evaluable patients with a median follow-up of 38 months (range, 10-64); 44 (72%) were treated with PT and 17 (28%) were treated with IMRT. The 2-year local control, locoregional control, distant metastasis-free survival, and overall survival were 98%, 97%, 98%, and 100%, respectively. There were 6 grade ≥3 events related to treatment. Two IMRT patients required percutaneous endoscopic gastrostomy tube placement during treatment secondary to significant nausea due to dysgeusia. Patients noted significant QOL improvement over time in the pain, swallowing, speech, social eating, social contact, mouth opening, and use of pain medication domains (all P < .02). The MBSImP overall severity score as well as oral and pharyngeal impairment scores showed stability with no significant change over time. For the 44 patients treated with PT, the mean D95 to the primary target was 10.7 Gy (standard deviation = 12.5 Gy). CONCLUSIONS: Mucosal sparing radiation is well tolerated in select resected human papillomavirus-related oropharyngeal squamous cell carcinoma with a low risk of recurrence at the mucosal primary site, a low rate of percutaneous endoscopic gastrostomy tube placement, and few radiation-related grade ≥3 adverse events.

Patterns and distribution of regional nodal involvement and recurrence in a surgically treated oropharyngeal squamous cell carcinoma cohort at a tertiary center.

OBJECTIVES: To investigate and describe the patterns of regional metastases and recurrences after surgical treatment of oropharyngeal squamous cell cancer (OPSCC). MATERIALS AND METHODS: Retrospective study of patients diagnosed with OPSCC from 2006 to 2021 at a tertiary referral center. Only patients treated with surgery including a neck dissection were included. Patients with unknown human papillomavirus (HPV) status, prior head and neck cancer, distant metastases, or synchronous head and neck cancer were excluded. RESULTS: A total of 928 patients were included. 89% were males, the average age was 58.6 years (range: 25.2-87.5), 874 (94%) were HPV(+), and 513 (55.3%) had a tonsil cancer. Among cN + patients, the most commonly involved levels at presentation were level II (85.2%), level III (33.3%), and level IV (9.4%). In cN0 patients, metastases were only observed in level II (16.2%) and level III (9.2%). Nodal recurrence occurred in 48 (5.2%) patients after a median time of 1.0 years (interquartile range: 0.6-2.0). Nodal recurrence incidence was similar in HPV(+) and HPV(-) patients (5.0% vs. 7.4%, p = 0.44). The most common levels for regional recurrence were ipsilateral level II (45.8%), contralateral level II (43.8%), and ipsilateral level V (25.0%). Multivariable analysis revealed that pN was a significant predictor for regional recurrence (p = 0.02). CONCLUSION: There is no difference in the distribution of regional metastases and recurrences in HPV(+) and HPV(-) OPSCC patients. Our findings align with the established understanding that regional metastases predominantly manifest in the ipsilateral level II-IV at presentation. Moreover, the data support the clinical recommendation to restrict elective neck dissection in cN0 patients to ipsilateral levels IIa and III, excluding level IIb. Regional recurrence is significantly associated with pN status.