Causes and impact of delays during the COVID-19 pandemic on head and neck cancer diagnosis.

BACKGROUND: The causes for delays during the COVID19 pandemic and their impact on head and neck cancer (HNC) diagnosis and staging are not well described. METHODS: Two cohorts were defined a priori for review and analysis-a Pre-Pandemic cohort (June 1 to December 31, 2019) and a Pandemic cohort (June 1 to December 31, 2020). Delays were categorized as COVID-19 related or not, and as clinician, patient, or policy related. RESULTS: A total of 638 HNC patients were identified including 327 in the Pre-Pandemic Cohort and 311 in the Pandemic Cohort. Patients in the Pandemic cohort had more N2-N3 category (41% vs. 33%, p = 0.03), T3-T4 category (63% vs. 50%, p = 0.002), and stage III-IV (71% vs. 58%, p < 0.001) disease. Several intervals in the diagnosis to treatment pathway were significantly longer in the pandemic cohort as compared to the Pre-Pandemic cohort. Among the pandemic cohort, 146 (47%) experienced a delay, with 112 related to the COVID-19 pandemic; 80 (71%) were clinician related, 15 (13%) were patient related, and 17 (15%) were policy related. CONCLUSIONS: Patients in the Pandemic cohort had higher stage disease at diagnosis and longer intervals along the diagnostic pathway, with COVID-19 related clinician factors being the most common cause of delay.

Telemedicine-enabled biofeedback electropalatography rehabilitation (TEBER): A pilot study for patients treated with surgery for oral cavity carcinoma.

BACKGROUND: To address the rehabilitative barriers to frequency and precision of care, we conducted a pilot study of a biofeedback electropalatography (EPG) device paired with telemedicine for patients who underwent primary surgery +/- adjuvant radiation for oral cavity carcinoma. We hypothesized that lingual optimization followed by telemedicine-enabled biofeedback electropalatography rehabilitation (TEBER) would further improve speech and swallowing outcomes after "standard-of-care" SOC rehabilitation. METHOD: Pilot prospective 8-week (TEBER) program following 8 weeks of (SOC) rehabilitation. RESULTS: Twenty-seven patients were included and 11 completed the protocol. When examining the benefit of TEBER independent of standard of care, "range-of-liquids" improved by +0.36 [95% CI, 0.02-0.70, p = 0.05] and "range-of-solids" improved by +0.73 [95% CI, 0.12-1.34, p = 0.03]. There was a positive trend toward better oral cavity obliteration; residual volume decreased by -1.2 [95% CI, -2.45 to 0.053, p = 0.06], and "nutritional-mode" increased by +0.55 [95% CI, -0.15 to 1.24, p = 0.08]. CONCLUSION: This pilot suggests that TEBER bolsters oral rehabilitation after 8 weeks of SOC lingual range of motion.

Implication of dental insurance status on patterns of pre-radiation dental extraction and risk of osteoradionecrosis of the jaw in head-and-neck cancer patients.

Oral toxicities such as osteoradionecrosis can be minimized by dental screening and prophylactic dental care prior to head and neck (HN) radiation therapy (RT). However, limited information is available about how dental insurance interacts with prophylactic dental care and osteoradionecrosis. To address this gap in knowledge, we conducted a cohort study of 2743 consecutive adult patients treated with curative radiation for HN malignancy who underwent pre-radiation dental assessment and where required, prophylactic dental treatment. Charts were reviewed to determine patient demographics, dental findings, dental treatment and development of osteoradionecrosis following radiation. Three insurance cohorts were identified: private-insured (50.4 %), public-insured (7.3 %), being patients with coverage through government-funded disability and welfare programs, and self-pay (42.4 %). More than half the public-insured patients underwent prophylactic pre-radiation dental extractions, followed by self-pay patients (44 %) and private-insured patients (26.6 %). After a median follow-up time of 4.23 years, 6.5 % of patients developed osteoradionecrosis. The actuarial rate of osteoradionecrosis in the public-insured patients was 14.7 % at 5-years post-RT, compared to 7.5 % in private-insured patients and 6.7 % in self-pay patients. On multivariable analysis, dental insurance status, DMFS160, age at diagnosis, sex, tumor site, nodal involvement, years smoked and gross income were all significant risk factors for tooth removal prior to HN radiation. However, only public-insured status, tumor site and years smoked were significant risk factors for development of osteoradionecrosis. Our findings demonstrate that lack of comprehensive dental coverage (patients who self-pay or who have limited coverage under public-insured programs) associates strongly with having teeth removed prior to HN RT. Nearly 1 in 6 patients covered under public-insurance developed osteoradionecrosis within 5 years of completing their treatment. Well-funded dental insurance programs for HN cancer patients might reduce the number of pre-RT extractions performed in these patients, improving quality of life post-RT.

Effect of Radiation Therapy Quality Assurance on Nasopharyngeal Carcinoma: Usage of a Novel, Web-Based Quality Assurance Application.

PURPOSE: We used a new web application for rapid review of radiation therapy (RT) target volumes to evaluate the relationship between target delineation compliance with the international guidelines and outcomes of definitive RT for nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: The data set consisted of computed tomography simulation scans, RT structures, and clinical data of 354 patients with pathology-confirmed NPC treated with intensity modulated RT between 2005 and 2017. Target volumes were peer-reviewed in RT quality assurance rounds, and target contours were revised, if recommended, before treatment. We imported the contours of intermediate-risk clinical target volumes of the primary tumor (CTVp) of 332 patients into the application. Inclusion of anatomic sites within intermediate-risk CTVp was determined in accordance with 2018 international guidelines for CTV delineation for NPC and correlated with time to local failure (TTLF) using Cox regression. RESULTS: In the peer-review quality assurance analysis, local and distant control and overall survival rates were similar between peer-reviewed and nonreviewed cases and between cases with and without target contour changes. In the CTV compliance analysis, with a median follow-up of 5.6 years, 5-year TTLF and overall survival rates were 93.1% and 85.9%, respectively. The most frequently non-guideline-compliant anatomic sites were sphenoid sinus (n = 69, 20.8%), followed by cavernous sinus (n = 38, 19.3%), left and right petrous apices (n = 37 and 32, 11.1% and 9.6%), and clivus (n = 14, 4.2%). Among 23 patients with a local failure (6.9%), the number of noncompliant cases was 8 for sphenoid sinus, 7 cavernous sinus, 4 left and 3 right petrous apices, and 2 clivus. Cavernous sinus-conforming cases showed higher TTLF in comparison with nonconforming cases (93.6% vs 89.1%, P = .013). Multivariable analysis confirmed that cavernous sinus noncompliance was prognostic for TTLF. CONCLUSIONS: Our application allowed rapid quantitative review of CTVp in a large NPC cohort. Although compliance with the international guidelines was high, undercoverage of the cavernous sinus was correlated with TTLF.

The collateral impact of the COVID-19 pandemic on HPV-positive oropharyngeal cancer diagnosis.

PURPOSE: We aim to assess the potential impact of the COVID-19 pandemic on diagnostic delays in HPV-positive oropharyngeal cancer (OPC), and to describe their underlying reasons. METHODS: All HPV + OPC referred to a tertiary cancer centre and diagnosed between June-December 2019 (Pre-Pandemic cohort) vs June-December 2020 (Pandemic cohort) were reviewed. TNM classification, gross-tumor-volumes (GTV) and intervals between sign/symptom onset and treatment initiation were compared between the cohorts. Reasons for delay (>6 months from onset of signs/symptoms to a positive biopsy of the primary tumor, or a delay specifically mentioned in the patient chart) in establishing the diagnosis were recorded per clinician's documentation, and categorized as COVID-related or non-COVID-related. RESULTS: A total of 157 consecutive HPV + OPC patients were identified (Pre-Pandemic: 92; Pandemic: 65). Compared to the Pre-Pandemic cohort, Pandemic cohort patients had a higher proportion of N2-N3 (32 % vs 15 %, p = 0.019) and stage III (38 % vs 23 %, p = 0.034) disease at presentation. The differences in proportions with > 6 months delay from symptom onset to establishing the diagnosis (29 % vs 20 %, p = 0.16) or to first treatment (49 % vs 38 %, p = 0.22) were not statistically different. 47 % of diagnostic delays in the Pandemic cohort were potentially attributable to COVID-19. CONCLUSION: We observed a collateral impact of the COVID-19 pandemic on HPV + OPC care through more advanced stage at presentation and a non-significant but numerically longer interval to diagnosis. This could adversely impact patient outcomes and future resource allocation. Both COVID-19-related and unrelated factors contribute to diagnostic delays. Tailored interventions to reduce delays are warranted.

Influence of anterior tumor location on survival after resection of lung cancer invading the thoracic inlet (Pancoast tumors).

OBJECTIVE: Superior sulcus tumors are a challenging subset of non-small cell lung carcinomas invading the thoracic inlet. In this study, we determined whether the location of the tumor along the first rib had an influence on survival. METHODS: We performed a review of 92 consecutive patients undergoing surgery for non-small cell lung carcinomas invading the thoracic inlet between January 1996 and June 2021. Tumor location was categorized into anterior and posterior based on predefined zones. RESULTS: In total, 21 tumors were located anteriorly (23%) and 71 posteriorly (77%). The rate of R0 resection (81% vs 87%; P = .4) and pathological complete response to induction therapy (33% vs 37%; P = .8) were similar between locations. After a median follow-up of 5.8 years (range, 0.8-24 years), 49 patients died for an overall survival of 48% (95% CI, 38%-59%) at 5 years. The 5-year survival was favorably influenced by R0 (vs R1) resection (51% vs 29%; P = .02), pathological complete response (vs no pathological complete response) (69% vs 31%; P = .03), posterior (vs anterior) location (56% vs 22%; P = .01), and ≤60 (vs >60) years of age (61% vs 37%; P = .007). Compared with posterior tumors, anterior tumors were associated with higher risk of systemic recurrence and significantly greater survival benefit from pathological complete response. Anterior tumors remained an independent predictor of worse survival in multivariate analysis (hazard ratio, 2.3; 95% CI, 1.2-4.5; P = .01). CONCLUSIONS: The anatomical location of the tumor affects survival after resection of non-small cell lung carcinomas invading the thoracic inlet. Anterior tumors have greater propensity to metastasize and may derive greater benefit from optimal systemic therapy than posterior tumors.

3'-Deoxy-3'-(18F) Fluorothymidine Positron Emission Tomography/Computed Tomography in Non-small Cell Lung Cancer Treated With Stereotactic Body Radiation Therapy: A Pilot Study.

Purpose: The primary objective was to compare 3'-deoxy-3'-(18F) fluorothymidine (FLT) positron emission tomography (PET)/computed tomography (CT) uptake in 3 cohorts of stereotactic body radiation therapy (SBRT) patients: (1) pre-SBRT, (2) stable post-SBRT lung fibrosis, and (3) suspicious or proven local recurrence post-SBRT. The secondary objectives were to optimize FLT-PET imaging by comparing FLT uptake in respiratory-gated (4-dimensional) versus nongated (3-dimensional) FLT-PET scans. Methods: Patients with early-stage non-small cell lung cancer planned or treated with SBRT at the institution with radiographic findings of fibrosis or recurrence were eligible for the study. All patients underwent imaging with FLT-PET/CT before SBRT in cohort 1 and at fibrosis or recurrence in cohort 2 and 3, respectively. The planned sample size was 20 patients in each cohort, with 60 patients total. FLT-PET standardized uptake value (SUV) variables including SUVmax, SUVmean, SUVpeak, SUV50, and SUV95 were compared among the 3 cohorts using the Kruskal-Wallis test. The correlation of respiratory-gated and nongated FLT-PET SUV variables was performed using the Spearman correlation coefficient. Results: Forty-one patients were recruited for the study (20 in cohort 1, 16 in cohort 2, and 5 in cohort 3) between 2015 and 2019. The majority received a diagnosis of stage I lung cancer (86%), and the most common prescription was 48 Gy in 4 fractions (59%). Respiratory-gated FLT-PET was performed in 35 patients. The FLT SUV variables were well correlated between respiratory-gated and nongated scans (r = 0.8-1.0). The SUVpeak, SUVmean, and SUVmax were significantly lower in the fibrosis cohort compared with the recurrence and pretreatment cohorts. The SUV50 and SUV95 values in the recurrence cohort were statistically similar to the pretreatment cohort. Conclusions: FLT-PET/CT may be helpful in differentiating SBRT-related fibrosis from recurrence. Nongated FLT-PET/CT with reporting of SUVmax and SUV95 values is recommended.

Evaluation of risk-tailored individualized selection of radiation therapy target volume for head and neck carcinoma of unknown primary.

PURPOSE: Intensity-modulated radiation therapy (IMRT) has enabled risk-tailored approach to elective mucosal and nodal clinical target volumes (CTVs) in treatment of head and neck carcinoma of unknown primary (HNCUP). This study report outcomes following such approach. METHODS: HNCUP patients treated with definitive IMRT between 2005 and 2018 were reviewed. Local failure (LF), regional failure (RF), distant metastasis (DM), overall survival (OS) and grade ≥3 late toxicity (LT) were analyzed. Multivariable analysis (MVA) was used to identify OS predictors for entire cohort and cN2-3 subgroup. RESULTS: A total of 203 patients were eligible: cN1 (7%), cN2a (14%), cN2b (46%), cN2c (14%) and cN3 (19%). Among 118 patients with known HPV status (by p16 staining), 81 (68%) were positive. IMRT target volume spared contralateral tonsil (55%), bilateral or contralateral sides of hypopharynx (72%), nasopharynx (72%), larynx (87%) and contralateral uninvolved neck (21%). Median follow-up was 5 years. Five-year LF, RF, DM, OS, and LT were 3%, 14%, 10%, 79%, and 7% respectively. Four patients developed mucosal recurrence: 3 within and 1 at the margin of the elective mucosal CTV. None of ipsilateral neck irradiation patients failed in the contralateral uninvolved neck. MVA identified cN2c-N3, HPV-negative status and older age as predictors for inferior OS. Within cN2-3 subgroup (n = 189): cN2c-N3, HPV-negative status and older age predicted lower OS, while concurrent chemotherapy was associated with better OS. CONCLUSION: Definitive IMRT with risk-adaptive radiation volume de-escalation for HNCUP resulted in high probability of tumor control with acceptable rate of late toxicity.

Extra-Pleural Pneumonectomy (EPP) in Children and Adults with Locally Advanced Sarcoma: A CanSaRCC Study.

Sarcoma can present as locally advanced disease involving pleura for which extra-pleural pneumonectomy (EPP) may be the only surgical option to ensure adequate local control. Data were collected on patients who underwent EPP between January 2009 and August 2021 at Princess Margret Hospital and SickKids (Toronto) using the CanSaRCC (Canadian Sarcoma Research and Clinical Collaboration). Ten patients with locally advanced sarcoma involving the pleura, aged 4 to 59 years (median 19.5 years) underwent EPP. Nine (90%) received pre-operative chemotherapy and eight (80%) achieved an R0 resection. Hemithoracic radiation was administered preoperatively (n = 6, 60%) or postoperatively (n = 4, 40%). Five (50%) patients were alive without disease at last follow-up (median 34.2 months) and time from EPP to last FU was median 29.2 months (range 2.2-87.5). Two patients (20%) had local recurrence, 4.3 and 5.8 months from EPP, and both died from progressive disease, 13.1 and 8.2 months from EPP, respectively. One patient died from brain metastasis (17 months), one died from radiation associated osteosarcoma (66 months), and one died from surgical complications (heart failure from constrictive pericarditis). EPP offers a feasible and life-prolonging surgical consideration for patients with locally advanced sarcoma involving the pleura in combination with chemotherapy and radiation. Consequently, EPP should be considered during multi-disciplinary tumor board discussions at high-volume centers.

Clinical presentation and outcome of human papillomavirus-positive nasopharyngeal carcinoma in a North American cohort.

BACKGROUND: The objective of this study was to describe the clinical presentation and outcomes of human papillomavirus (HPV)-positive nasopharyngeal cancer (NPC) versus Epstein-Barr virus (EBV)-positive NPC and HPV-positive oropharyngeal cancer (OPC). METHODS: Clinical characteristics and presenting signs/symptoms were compared between patients who had viral-related NPC versus viral-related OPC treated with intensity-modulated radiotherapy from 2005 to 2020 and who were matched 1:1 (by tumor and lymph node categories, smoking, age, sex, histology, and year of diagnosis). Locoregional control (LRC), distant control (DC), and overall survival (OS) were compared using the 2005-2018 cohort to maintain 2 years of minimum follow-up. Multivariable analysis was used to evaluate the cohort effect. RESULTS: Similar to HPV-positive OPC (n = 1531), HPV-positive NPC (n = 29) occurred mostly in White patients compared with EBV-positive NPC (n = 422; 86% vs. 15%; p < .001). Primary tumor volumes were larger in HPV-positive NPC versus EBV-positive NPC (median volume, 51 vs. 23 cm3 ; p = .002), with marginally more Level IB nodal involvement. More patients with HPV-positive NPC complained of local pain (38% vs. 3%; p = .002). The median follow-up for the 2005-2018 cohort was 5.3 years. Patients who had HPV-positive NPC (n = 20) had rates of 3-year LRC (95% vs. 90%; p = .360), DC (75% vs. 87%; p = .188), and OS (84% vs. 89%; p = .311) similar to the rates in those who had EBV-positive NPC (n = 374). Patients who had HPV-positive NPC also had rates of LRC (95% vs. 94%; p = .709) and OS (84% vs. 87%; p = .440) similar to the rates in those who had HPV-positive OPC (n = 1287). The DC rate was lower in patients who had HPV-positive disease (75% vs. 90%; p = .046), but the difference became nonsignificant (p = .220) when the analysis was adjusted for tumor and lymph node categories, smoking, and chemotherapy. CONCLUSIONS: HPV-positive NPC and EBV-positive NPC seem to be mutually exclusive diseases. Patients who have HPV-positive NPC have greater local symptom burden and larger primary tumors but have similar outcomes compared with patients who have EBV-positive NPC or HPV-positive OPC.

Small molecule allosteric inhibitors of RORγt block Th17-dependent inflammation and associated gene expression in vivo.

Retinoic acid receptor-related orphan nuclear receptor (ROR) γt is a member of the RORC nuclear hormone receptor family of transcription factors. RORγt functions as a critical regulator of thymopoiesis and immune responses. RORγt is expressed in multiple immune cell populations including Th17 cells, where its primary function is regulation of immune responses to bacteria and fungi through IL-17A production. However, excessive IL-17A production has been linked to numerous autoimmune diseases. Moreover, Th17 cells have been shown to elicit both pro- and anti-tumor effects. Thus, modulation of the RORγt/IL-17A axis may represent an attractive therapeutic target for the treatment of autoimmune disorders and some cancers. Herein we report the design, synthesis and characterization of three selective allosteric RORγt inhibitors in preclinical models of inflammation and tumor growth. We demonstrate that these compounds can inhibit Th17 differentiation and maintenance in vitro and Th17-dependent inflammation and associated gene expression in vivo, in a dose-dependent manner. Finally, RORγt inhibitors were assessed for efficacy against tumor formation. While, RORγt inhibitors were shown to inhibit tumor formation in pancreatic ductal adenocarcinoma (PDAC) organoids in vitro and modulate RORγt target genes in vivo, this activity was not sufficient to delay tumor volume in a KP/C human tumor mouse model of pancreatic cancer.

Prognostic importance of radiologic extranodal extension in nasopharyngeal carcinoma treated in a Canadian cohort.

PURPOSE: To confirm the prognostic value of radiologic extranodal extension (rENE) and its role in clinical-N classification in nasopharyngeal carcinoma (NPC) treated in a western institution. METHODS AND MATERIALS: NPC treated between 2010 and 2017 were included. Pre-treatment MRI were reviewed for unequivocal rENE and its grade: grade-1: tumour invading through any nodal capsule but confined to perinodal fat; grade-2: ≥2 adjacent nodes forming a coalescent nodal mass; grade-3: tumour extending beyond perinodal fat to invade/encase adjacent structures. Overall survival (OS) and disease-free survival (DFS) were compared between rENE-positive (rENE+) and rENE-negative (rENE-) patients. Multivariable analysis (MVA) confirmed the prognostic importance of rENE and its grade. Staging schemas including rENE in N-classification were proposed and their performance evaluated. RESULTS: A total of 274 patients were eligible (43 cN0; 231 cN-positive). rENE was identified in 83/231 (36%) cN-positive, including grade 1/2/3 rENE in 14/58/11 cases. Compared to rENE-, rENE+ patients had a lower OS (68% vs 89%, p < 0.001) and DFS (58% vs 80%, p < 0.001). MVA confirmed the prognostic importance of grade-2 [HR: OS: 2.85 (p = 0.005); DFS: 2.89 (p < 0.001)] and grade-3 rENE [HR: OS 5.28 (p = 0.004); DFS 3.86 (p = 0.005)], with a trend for grade-1 vs rENE- [HR: OS 2.63 (p = 0.13); DFS 1.49 (p = 0.520)]. We evaluated classifying any rENE as cN3 (Proposal-I) or any grade-2/grade-3 rENE as cN3 (Proposal-II). The stage schema with Proposal-I cN-classification ranked the highest in the performance evaluation. CONCLUSIONS: rENE is an important prognostic factor in this western NPC cohort. We propose classifying any unequivocal rENE as cN3.

Limited-stage small cell lung cancer: Outcomes associated with prophylactic cranial irradiation over a 20-year period at the Princess Margaret Cancer Centre.

BACKGROUND & PURPOSE: Prophylactic cranial irradiation (PCI) is recommended for limited-stage small-cell lung cancer (LS-SCLC) patients with good response to concurrent chemoradiation. We report our institution's 20-year experience with this patient population and associated clinical outcomes. MATERIALS & METHODS: A retrospective cohort of consecutive LS-SCLC patients treated with curative intent chemoradiation at our institution (1997-2018) was reviewed. Overall survival (OS) was calculated using the Kaplan-Meier method, and significant covariates determined by the Cox proportional hazards model. Covariates predictive of PCI were determined using Fisher's exact test and the Mann-Whitney test. Brain failure risk (BFR) was calculated using the cumulative incidence method treating death as a competing event. Treatment cohorts (historic vs. contemporary) were stratified by the median year of diagnosis (2005). RESULTS: A total of 369 patients with LS-SCLC were identified, of which 278 patients were notionally PCI eligible. PCI was given to 196 patients (71%). Younger age was associated with PCI utilization (p < 0.001). PCI utilization rates did not change between the historic and contemporary treatment era (p = 0.11), whereas magnetic resonance imaging (MRI) use at baseline and follow-up became more prevalent in the contemporary era (p = <0.001). On multivariable analysis, PCI utilization was associated with improved OS (HR 1.88, 95% CI 1.32-2.69) and decreased BFR (HR 4.66, 95% CI 2.58-8.40). Patients who had MRI follow-up had a higher incidence of BFR (HR 0.35, 95% CI 0.18-0.66) in multivariable analyses. CONCLUSIONS: For LS-SCLC patients at our institution, PCI is more frequently utilized in younger patients, and the utilization rate did not change significantly over the past 20 years. PCI was independently associated with improved OS and lower BFR. Omission of PCI in LS-SCLC patients should not be routinely practiced in the absence of further prospective data.

Outcome and treatment toxicity in east-indian versus white-canadian patients with oral cavity cancer following postoperative (chemo-)radiotherapy delivered under similar multidisciplinary care: A propensity-matched cohort study.

PURPOSE: We compare clinical behaviour of East-Indians and White-Canadians with oral cavity squamous cell carcinoma (OSCC) treated at a Western institution within a uniform health care system. MATERIALS/METHODS: Newly diagnosed OSCC patients who underwent postoperative (chemo-)radiotherapy (PORT/POCRT) between 2005 and 2017 were included. Data on ethnicity and other variables were extracted from patient-questionnaires, a prospective database and supplemented by chart review. Baseline characteristics were compared between East-Indian versus White-Canadian groups. A propensity-matched (1:1 ratio) of East-Indian versus White-Canadian cohorts was generated to compare locoregional control (LRC), distant control (DC), overall survival (OS), and acute and late toxicities. RESULTS: A total of 53 East-Indian and 467 White-Canadian OSCC patients were identified. Compared to White-Canadians, East-Indian patients were younger, had less exposure to smoking and alcohol (p < 0.001), but more chewed betel (areca) nut /tobacco (43% vs 0.2%, p < 0.001). Buccal/retromolar-trigone/lower gingiva primaries were more common in East-Indians (49% vs 25%, p < 0.001). Median follow-up was 5.0 years. Propensity-score paired analysis revealed inferior 3-year LRC (68% vs 81%, p = 0.030), non-significantly lower OS (61% vs 75%, p = 0.257), but similar DC (81% vs 87%, p = 0.428) in East-Indian versus White-Canadian patients. Actuarial rate of toxicities was higher in East-Indians vs White-Canadians: acute toxicity at 6 weeks: 47% vs 30%, p = 0.012; chronic trismus at 5-years: 16% vs 2%, p = 0.013. CONCLUSION: East-Indian OSCC patients have a greater betel nut/ chewable tobacco exposure compared to White-Canadians and a different distribution of OSCC sites. Propensity-matched cohort analysis showed lower LRC and higher toxicities in East-Indian OSCC patients, suggesting a complicated interaction between genetic/biological and life-style factors.

Head and neck imaging surveillance strategy for HPV-positive oropharyngeal carcinoma following definitive (chemo)radiotherapy.

PURPOSE: To describe the utilization pattern of head and neck (HN) surveillance imaging and explore the optimal strategy for radiologic "residual" lymph node (LN) surveillance following definitive (chemo)radiotherapy (RT/CRT) in human papillomavirus (HPV)+ oropharyngeal carcinoma (OPC). METHODS: All HPV+ OPC patients who completed RT/CRT from 2012 to 2015 were included. Schedule and rationale for post-treatment HN-CT/MRI were recorded. Imaging findings and oncologic outcomes were evaluated. RESULTS: A total of 1036 scans in 412 patients were reviewed: 414 scans for first post-treatment response assessment and 622 scans for the following reasons: follow-up of radiologic "residual" LN(s) (293 scans/175 patients); local symptoms (227/146); other (17/16); unknown (85/66). Rate of scans with "unstated" reason varied significantly among clinicians (3-28%, p < 0.001) and none of them yielded any positive imaging findings. First post-treatment scans identified 192 (47%) patients with radiologic "residual" LNs. Neck dissection (ND) was performed in 28 patients: 16 immediately (6/16 positive), 10 after one follow-up scan (2/10 positive), and 2 after 2nd follow-up scan (1/2 positive). Thirty patients had >2 consecutive follow-up scans at 2-3-month intervals, and none showed subsequent imaging progression or regional failure. CONCLUSIONS: Pattern of HN imaging utilization for surveillance varied significantly among clinicians. Imaging surveillance reduces the need for ND. However, routine HN-CT/MR surveillance without clinical symptoms/signs does not demonstrate proven value in identifying locoregional failure or toxicity. Radiologic "residual" LNs without adverse features are common. If two subsequent follow-up scans demonstrate stable/regressing radiologic "residual" LNs, clinical surveillance without further imaging appears to be safe in this population.

Prognostic value of clinical and radiologic extranodal extension and their role in the 8th edition TNM cN classification for HPV-negative oropharyngeal carcinoma.

BACKGROUND/OBJECTIVES: We evaluate the performance between the TNM-8 versus TNM-7 cN-classification and explore the relative prognostic contribution of radiologic extranodal extension (rENE) for HPV-negative oropharyngeal cancer (HPV-OPC). MATERIALS/METHODS: All HPV- OPC treated with IMRT between 2005 and 2016 were included. cENE was defined as unambiguous "fixation" of a neck mass or "skin involvement" on clinical examination. rENE was recorded by re-reviewing pre-treatment CT/MR. Disease-free survival (DFS) stratified by cENE or rENE were compared. Multivariable analyses (MVA) calculated the adjusted hazard ratio (aHR) for the separate cENE and rENE attributes and their combination. A refined cN-category incorporating both cENE and rENE parameters was proposed. The performance of the revision was compared to TNM-8 and TNM-7. RESULTS: Of 361 HPV- OPC, 97 were cN0 and 264 were cN+ with 48 cENE+ and 72 rENE+ respectively. Median follow-up was 5.4 years. The 3-year DFS was lower in cENE+ vs cENE-negative (cENE-) (23% vs 45%; aHR = 1.68, p = 0.008) and rENE+ vs rENE-negative (rENE-) patients (29% vs 45%; aHR = 1.44, p = 0.037). The cENE+/rENE+ subset had the worse DFS vs cENE-/rENE+ or cENE-/rENE- (24%/37%/46%, p = 0.005). We propose a refined cN-category wherein any cENE-/rENE+ case is reclassified one N-stratum higher while any cENE+ case remains cN3b. The stage schema with the refined N-categorization outperformed TNM-8, and both outperformed TNM-7. CONCLUSIONS: cENE and rENE are both prognostic but the cENE+/rENE+ subset has the worst outcome. The TNM-8 cN-categories improves outcome prediction compared to the TNM-7. Incorporation of rENE into TNM-8 cN-categories may further augment performance.

Non-operative management for oral cavity carcinoma: Definitive radiation therapy as a potential alternative treatment approach.

PURPOSE: To determine the outcomes of oral cavity squamous cell cancer (OSCC) patients treated with non-surgical approach i.e. definitive intensity-modulated radiation therapy (IMRT). METHODS: All OSCC patients treated radically with IMRT (without primary surgery) between 2005-2014 were reviewed in a prospectively collected database. OSCC patients treated with definitive RT received concurrent chemotherapy except for early stage patients or those who declined or were unfit for chemotherapy. The 5-year local, and regional, distant control rates, disease-free, overall, and cancer-specific survival, and late toxicity were analyzed. RESULTS: Among 1316 OSCC patients treated with curative-intent; 108 patients (8%) received non-operative management due to: medical inoperability (n = 14, 13%), surgical unresectability (n = 8, 7%), patient declined surgery (n = 15, 14%), attempted preservation of oral structure/function in view of required extensive surgery (n = 53, 49%) or extensive oropharyngeal involvement (n = 18, 17%). Sixty-eight (63%) were cT3-4, 38 (35%) were cN2-3, and 38 (35%) received concurrent chemotherapy. With a median follow-up of 52 months, the 5-year local, regional, distant control rate, disease-free, overall, and cancer-specific survival were 78%, 92%, 90%, 42%, 50%, and 76% respectively. Patients with cN2-3 had higher rate of 5-year distant metastasis (24% vs 3%, p = 0.001), with detrimental impact on DFS (p = 0.03) and OS (p < 0.02) on multivariable analysis. Grade ≥ 3 late toxicity was reported in 9% of patients (most common: grade 3 osteoradionecrosis in 6%). CONCLUSIONS: Non-operative management of OSCC resulted in a meaningful rate of locoregional control, and could be an alternative curative approach when primary surgery would be declined, unsuitable or unacceptably delayed.

Short-term and long-term unstimulated saliva flow following unilateral vs bilateral radiotherapy for oropharyngeal carcinoma.

BACKGROUND: We aimed to compare unstimulated saliva flow using 3-minute modified Schirmer test (MST) following bilateral vs unilateral radiotherapy (RT) in oropharyngeal carcinoma (OPC). METHODS: We reviewed OPC patients treated with definitive intensity-modulated radiation therapy (IMRT) between 2011 and 2017. MST was measured at baseline, 1-/6-/12-/24-month post-RT. MST values were compared between bilateral-RT vs unilateral-RT groups. Multivariable logistic regression analysis (MVA) identified predictors of hyposalivation (MST < 25 mm). RESULTS: Total 498 bilateral-RT and 36 unilateral-RT patients were eligible. The MST values at 1-/6-/12-/24-month post-RT were all significantly reduced from baseline for the entire cohort. Baseline unilateral-RT and bilateral-RT MST values (in mm) were similar (P = .2), but much higher for unilateral-RT 1-month (mean: 19.1 vs 13.0, P = .03), 6-month (20.5 vs 9.3, P < .001), 12-month (20.1 vs 11.9, P < .01), and 24-month post-RT (22.2 vs 13.9, P = .04). MVA confirmed that unilateral RT reduced the likelihood of hyposalivation vs bilateral RT (OR 2.36, P = .006). CONCLUSION: Unilateral RT reduces unstimulated salivary flow in OPC patients.

Healthcare resource utilization following unilateral versus bilateral radiation therapy for oropharyngeal carcinoma.

PURPOSE: To describe differences in healthcare resource utilization between patients treated with bilateral vs. unilateral neck radiation therapy (RT) for lateralized oropharyngeal cancer. METHODS: A propensity score matching strategy was used to identify two otherwise clinically similar cohorts of tonsillar cancer patients treated with either bilateral or unilateral neck RT. Cohorts were matched based on similar propensity scores for age, sex, ECOG performance status, pack-year smoking history, cT-category, cN-category, HPV-status, and use of concurrent chemotherapy. Short term (from start of RT to 3 months following end of RT) resource utilization included: 1) outpatient supportive care visits, 2) hospital admission, and 3) interventions (feeding tube insertion and outpatient intravenous hydration). Long-term resource utilization included feeding tube dependency at 1-year. RESULTS: Among 559 patients with tonsillar cancer treated between 2004-2017, propensity score matching identified a unilateral neck RT cohort (n = 81) and bilateral neck RT cohort (n = 81) with similar clinical and treatment characteristics. Bilateral neck RT was associated with a higher likelihood of hospitalization (33% vs 12%, p < 0.01), outpatient IV hydration (33% vs 17%, p = 0.03), and feeding tube insertion (33% vs 10%, p < 0.001); a greater number of total days of hospitalization (110 vs 47 days, p < 0.01) and outpatient IV hydration (135 vs 72 days, p = 0.02); and higher total number of supportive clinic visits (1226 vs 1053 days, p = 0.04). In the long-term, bilateral RT was associated with higher rate of feeding tube dependency at 1-year (7% vs 0%, p < 0.001). CONCLUSION: Bilateral RT for tonsillar cancer resulted in significant increase in health resource utilization.

Cost-function testing methodology for image-based registration of endoscopy to CT images in the head and neck.

One of the largest geometric uncertainties in designing radiotherapy treatment plans for squamous cell cancers of the head and neck is contouring the gross tumor volume. We have previously described a method of projecting mucosal disease contours, visible on endoscopy, to volumetrically reconstructed planning computed tomography (CT) datasets, using electromagnetic (EM) tracking of a flexible endoscope, enabling rigid registration between endoscopic and CT images.However, to achieve better accuracy for radiotherapy planning, we propose refining this initial registration with image-based registration methods. In this paper, several types of cost functions are evaluated based on accuracy and robustness. Three phantoms and eight clinical cases are used to test each cost function, with initial registration of endoscopy to CT provided by the pose of the flexible endoscope recovered from EM tracking. Cost function classes include: cross correlation, mutual information and gradient methods. For each test case, a ground truth virtual camera pose was first defined by manual registration of anatomical features visible in both real and virtual endoscope images. A new set of evenly spaced fiducial points and a sample contour were created and projected onto the CT image to be used in assessing image registration quality. A new set of 5000 displaced poses was generated by random sampling displacements along each translational and rotational dimension. At each pose, fiducial and contour points in the real image were again projected on the CT image. The cost function, fiducial registration error and contouring error values were then calculated.While all cost functions performed well in select cases, only the normalized gradient field function consistently had registration errors less than 2 mm, which is the accuracy needed if this application of registering mucosal disease identified on optical image to CT images is to be used in the clinical practice of radiation treatment planning.(Registration: ClinicalTrials.gov NCT02704169).