Multimodality Management of EBV-Associated Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is a rare cancer of the nasopharyngeal mucosa with a specific geographic predisposition. NPC is often associated with Epstein-Barr Virus (EBV) infection and as a result contains many characteristic biomarkers. Treatment of locally-contained NPC is generally achieved through use of radiotherapy (RT), as part of a multimodality treatment regimen. Induction chemotherapy followed by concurrent RT and platinum-based chemotherapy regimen has emerged as the definitive treatment of choice for locoregionally-advanced NPC. Recently, immunotherapy is finding a role in the treatment of recurrent or metastatic NPC. Immune checkpoint blockade therapies targeted against the programmed death-1 (PD-1) receptor have demonstrated efficacy in early phase clinical trials, with ongoing phase III trials in effect. Biomarkers for treatment efficacy remain an ongoing area of investigation, with important prognostic implications on the horizon.

nab-Paclitaxel and cisplatin followed by cisplatin and radiation (Arm 1) and nab-paclitaxel followed by cetuximab and radiation (Arm 2) for locally advanced head and neck squamous-cell carcinoma: a multicenter, non-randomized phase 2 trial.

In locally advanced head and neck squamous-cell carcinoma (LA-HNSCC), clinical complete response (cCR) at the primary site, assessed by clinical examination, after induction chemotherapy predicts for a low relapse risk after subsequent chemoradiotherapy. Prior studies showed a cCR rate of 77% with induction nanoparticle albumin-bound (nab)-paclitaxel given with cisplatin and 5-fluorouracil (APF). The primary aims of this non-randomized phase 2 trial were to determine the cCR rate after induction nab-paclitaxel and cisplatin (Arm 1) and after nab-paclitaxel monotherapy (Arm 2). Eligibility required LA-HNSCC, T2-T4 stage classification, and suitable (Arm 1) or unsuitable (Arm 2) candidates for cisplatin. Arm 1 patients received nab-paclitaxel and cisplatin, then cisplatin with radiation. Arm 2 patients received nab-paclitaxel, then cetuximab with radiation. The primary endpoint was cCR after two cycles of induction chemotherapy. Each arm enrolled forty patients. cCR at the primary site occurred in 28 patients (70%) after nab-paclitaxel and cisplatin and in 8 patients (20%) after nab-paclitaxel monotherapy. The overall clinical response rate was 98% after nab-paclitaxel and cisplatin and 90% after nab-paclitaxel monotherapy. In subset analyses, cCR rates by T stage classifications (T2, T3, T4) were 54, 86, and 69% after nab-paclitaxel and cisplatin, and 14, 11, and 26% after nab-paclitaxel. cCR rates by human papillomavirus status (p16 positive oropharynx vs other) were 72 and 64% after nab-paclitaxel and cisplatin and 35 and 9% after nab-paclitaxel. The cCR rate after nab-paclitaxel and cisplatin was similar to APF; however, the cCR rate after nab-paclitaxel monotherapy was lower. The trial was registered at ClinicalTrials.gov NCT02573493 on October 9, 2015.

The Novel Use of a Commercially Available Video-Conference Platform to Facilitate Multidisciplinary Target Volume Review and Delineation for Skull-Base Radiation Therapy During the Coronavirus Disease 2019 Pandemic.

Multidisciplinary involvement in radiation therapy (RT) treatment planning is currently underused. A radiation oncologist sought input for generating target contours from a neuro-radiologist (NR) and otolaryngologist (OL) for 3 patients requiring skull-base RT during the coronavirus disease 2019 pandemic. A Health Insurance Portability and Accountability Act compliant virtual meeting between the radiation oncologist, NR, and OL was arranged. Involvement of the OL and NR led to significant changes in the clinical target volume for all patients. Our experience highlights the feasibility of using commercially available video-conference platforms for multidisciplinary target volume delineation for complex RT cases. Further applications include interdisciplinary contour review for RT cases requiring special expertise and joint attending/resident physician contour review for resident education. The video-conference platform technology has demonstrated benefit during the coronavirus disease 2019 pandemic, and we believe it will remain an integral component of our field moving forward.

Low-risk human papilloma virus positive oropharyngeal cancer with one positive lymph node: Equivalent outcomes in patients treated with surgery and radiation therapy versus surgery alone.

BACKGROUND: For human papilloma virus positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC), management recommendations for patients with a single metastatic lymph node <6 cm in diameter remain nebulous, leading to treatment heterogeneity in this common subgroup of patients. METHODS: We utilized the National Cancer Database to perform survival and multivariable analyses of patients with HPV+ OPSCC with one positive lymph node <6 cm and negative surgical margins. RESULTS: We found that 5-year survival is comparable between patients who receive surgery and adjuvant radiation versus surgery alone. In multivariable analyses, we found no significant difference in the hazard ratio of overall survival after adjusting for various potential confounders. CONCLUSIONS: These data suggest that patients with margin-negative HPV+ OPSCC with a single positive lymph node <6 cm have comparable survival with or without adjuvant radiation. Future studies exploring outcomes for this specific group in randomized-controlled trials will be critical for further evaluating these initial observations.

Regional lymph node irradiation in locally advanced Merkel cell carcinoma reduces regional and distant relapse and improves disease-specific survival.

BACKGROUND: One-third of patients with Merkel cell carcinoma (MCC) present with locally advanced disease involving the regional lymph nodes, but indications for regional lymph node radiation therapy (rLN-RT) are not well established. MATERIALS AND METHODS: 72 patients with locally advanced MCC were retrospectively reviewed. Regional lymph nodes were addressed with observation, lymph node dissection (LND) alone, definitive nodal radiotherapy (DnRT), or LND plus adjuvant nodal radiotherapy (AnRT). Cox regression was used to compare treatment modalities in terms of regional recurrence-free survival (RRFS), distant recurrence-free survival (DRFS), disease-free survival (DFS) and disease-specific survival (DSS). RESULTS: rLN-RT, including both DnRT and AnRT, improved RRFS (Hazard ratio (HR): 0.07, 95% confidence interval (CI): 0.01-0.40, p = 0.003), DRFS (HR: 0.28, CI: 0.11-0.76, p = 0.01), DFS (HR: 0.23, CI: 0.09-0.58, p = 0.002), and DSS (HR: 0.23, CI: 0.06-0.90, p = 0.03). AnRT improved DFS and DSS in high-risk subgroups (e.g., extranodal extension (ENE), ≥ 2 positive lymph nodes, or bulkier lymph nodes). The benefit of AnRT increased with higher disease burden. After controlling for these adverse factors, AnRT significantly improved RRFS (HR: 0.04, CI: 0.01-0.37, p = 0.004), DRFS (HR: 0.14, CI: 0.04-0.50, p = 0.003), DFS (HR: 0.09, CI: 0.02-0.33, p < 0.001), and DSS (HR: 0.21, CI: 0.05-0.89, p = 0.03). CONCLUSION: rLN-RT, including both DnRT and AnRT, reduces relapse and death from MCC in patients with node-positive disease. AnRT is particularly beneficial for patients with ENE, multiple involved lymph nodes, or larger nodal foci of disease. These results argue for more liberal use of nodal RT for MCC patients who present with node-positive disease.

Reduced Wide Local Excision Margins are Associated with Increased Risk of Relapse and Death from Merkel Cell Carcinoma.

INTRODUCTION: Current recommendations regarding the size of wide local excision (WLE) margins for Merkel cell carcinoma (MCC) are not well established. METHODS: WLE and pathologic margins were respectively reviewed from 79 patients with stage I or II MCC, who underwent WLE at Washington University in St Louis from 2005 to 2019. Outcomes included local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant recurrence-free survival (DRFS), disease-free survival (DFS), and disease-specific survival (DSS). RESULTS: Thirty-two percent of patients received adjuvant radiotherapy (aRT). At 1 year, DFS was 51.3%, 71.4%, and 87.8% for patients with WLE margins < 1 cm, 1-1.9 cm, and ≥ 2 cm, respectively (p = 0.02). At 3 years, the DSS was 57.7%, 82.6%, and 100% for patients with WLE margins < 1 cm, 1-1.9 cm, and ≥ 2 cm, respectively (p = 0.02). Multivariable Cox analysis demonstrated that every 1-cm increase in WLE margins was associated with improved RRFS [hazard ratio (HR) = 0.28, 95% confidence interval (CI): 0.11-0.75], DRFS (HR 0.30, CI 0.08-0.99), DFS (HR 0.42, CI 0.21-0.86), and DSS (HR 0.16, CI 0.04-0.61). WLE and pathologic margin size were moderately-to-strongly correlated (r = 0.66). Close or positive pathologic margins (< 3 mm) were associated with reduced DRFS (HR 6.83, CI 1.80-25.9), DFS (HR 2.98, CI 1.31-6.75), and DSS (HR 3.52, CI 1.14-10.9). CONCLUSION: Reduced WLE and pathologic margins were associated with higher risk of relapse and death from MCC. Larger WLE margins are important in populations with lower rates of adjuvant radiation.

Outcomes of Patients With Single-Node Metastasis of Human Papillomavirus-Related Oropharyngeal Cancer Treated With Transoral Surgery.

Importance: Regional lymph node metastasis remains an important prognostic factor in patients with oropharyngeal squamous cell carcinoma (OPSCC). Although survival among patients with regional metastasis in human papillomavirus (HPV)-related OPSCC is more favorable compared with patients who are HPV negative, prognostic variables associated with failure in patients with single-node metastasis are not known. Objective: To evaluate recurrence and survival in patients with HPV-related OPSCC with single-lymph node metastasis treated with transoral surgery. Design, Setting, and Participants: A retrospective cohort study was conducted of 207 adults with newly diagnosed p16-positive OPSCC and pathology-confirmed single-node disease who underwent surgical resection with or without adjuvant therapy at 2 tertiary academic medical centers from January 1, 2007, to December 31, 2016. Statistical analysis was performed from September 1, 2018, to September 1, 2020. Interventions: Surgery alone (n = 59), surgery with adjuvant radiation (n = 75), or surgery with adjuvant chemoradiation (n = 73). Main Outcomes and Measures: The primary outcome was regional recurrence. Secondary outcomes included overall survival, any recurrence, and identification of factors associated with regional recurrence and overall survival. Results: Among 207 patients, 178 (86%) were men, with a median age of 57 years (range, 35-82 years) at the time of surgery. Median follow-up was 36.2 months (range, 7-127 months). Regional recurrence occurred in 11 patients (5%). Of these, 1 patient (9%) was lost to follow-up after diagnosis, 1 (9%) was treated with palliative chemotherapy, and 9 (82%) were treated with curative intent. Ultimately, 7 patients received successful salvage treatment, and 3 died with disease. Overall, there were 21 patients (10%) with any recurrence, with 4 patients (19%) experiencing local recurrence, 11 (52%) experiencing regional recurrence, and 6 (29%) experiencing distant metastasis. The 5-year overall survival was 95% (95% CI, 89%-98%) for all patients. Older age (odds ratio [OR], 1.2; 95% CI, 1.1-1.2), advanced T stage (OR, 3.5; 95% CI, 0.9-14.0), and positive margins (OR, 10.9; 95% CI, 1.8-67.5) were associated with increased regional recurrence. Extranodal extension (OR, 0.2; 95% CI, 0.04-0.8), lymph node size greater than 3 cm (OR, 0.2; 95% CI, 0.1-0.7), and adjuvant therapy (OR, 0.08; 95% CI, 0.02-0.4) were associated with decreased regional recurrence. Advanced comorbidities (hazard ratio, 6.20; 95% CI, 1.4-27.7), lymphovascular invasion (hazard ratio, 4.7; 95% CI, 1.0-21.2), and regional recurrence (hazard ratio, 16.0; 95% CI, 3.1-82.0) were associated with worse overall survival. Conclusions and Relevance: The findings of this cohort study suggest that patients with HPV-related OPSCC and single-node disease undergoing surgical resection with or without adjuvant treatment have excellent survival. Adjuvant therapy appears to improve regional control. Among patients with regional recurrence of OPSCC, there is a high rate of successful salvage treatment.

Radiation and Checkpoint Inhibitor Immunotherapy Lead to Long Term Disease Control in a Metastatic RCC patient With Brain Metastases.

Renal cell carcinoma (RCC) comprises 4.2% of all new cancer cases in the United States and 30% of cases are metastatic (mRCC) at diagnosis. Brain metastatic RCC historically has poor prognosis, but the development of immune checkpoint inhibitors has revolutionized their care and may be successfully combined with SBRT to improve prognosis. Here, we present a case of a patient with mRCC who had brain metastases treated with concurrent immune checkpoint inhibitors and SBRT. He continues to survive with good functional status years following his initial diagnosis. We discuss the relevant history regarding treatment approach in patients with brain metastatic RCC, ongoing trials focusing on the combination of immunotherapy and radiation, and the potential and promise of the abscopal effect.

Neoadjuvant and Adjuvant Pembrolizumab in Resectable Locally Advanced, Human Papillomavirus-Unrelated Head and Neck Cancer: A Multicenter, Phase II Trial.

PURPOSE: Pembrolizumab improved survival in patients with recurrent or metastatic head and neck squamous-cell carcinoma (HNSCC). The aims of this study were to determine if pembrolizumab would be safe, result in pathologic tumor response (pTR), and lower the relapse rate in patients with resectable human papillomavirus (HPV)-unrelated HNSCC. PATIENTS AND METHODS: Neoadjuvant pembrolizumab (200 mg) was administered and followed 2 to 3 weeks later by surgical tumor ablation. Postoperative (chemo)radiation was planned. Patients with high-risk pathology (positive margins and/or extranodal extension) received adjuvant pembrolizumab. pTR was quantified as the proportion of the resection bed with tumor necrosis, keratinous debris, and giant cells/histiocytes: pTR-0 (<10%), pTR-1 (10%-49%), and pTR-2 (≥50%). Coprimary endpoints were pTR-2 among all patients and 1-year relapse rate in patients with high-risk pathology (historical: 35%). Correlations of baseline PD-L1 and T-cell infiltration with pTR were assessed. Tumor clonal dynamics were evaluated (ClinicalTrials.gov NCT02296684). RESULTS: Thirty-six patients enrolled. After neoadjuvant pembrolizumab, serious (grades 3-4) adverse events and unexpected surgical delays/complications did not occur. pTR-2 occurred in eight patients (22%), and pTR-1 in eight other patients (22%). One-year relapse rate among 18 patients with high-risk pathology was 16.7% (95% confidence interval, 3.6%-41.4%). pTR ≥10% correlated with baseline tumor PD-L1, immune infiltrate, and IFNγ activity. Matched samples showed upregulation of inhibitory checkpoints in patients with pTR-0 and confirmed clonal loss in some patients. CONCLUSIONS: Among patients with locally advanced, HPV-unrelated HNSCC, pembrolizumab was safe, and any pathologic response was observed in 44% of patients with 0% pathologic complete responses. The 1-year relapse rate in patients with high-risk pathology was lower than historical.

Duration of radiation therapy is associated with worse survival in head and neck cancer.

INTRODUCTION: Delays in radiation are multifactorial, frequent, and associated with poor outcomes. This study investigates the effect of both primary and adjuvant radiation therapy duration and their interaction with other measures of treatment delay on survival in head and neck squamous cell carcinoma (HNSCC). METHODS: We built a retrospective cohort using the National Cancer Database, consisting of primary oral cavity, hypopharynx, larynx and oropharynx squamous cell carcinoma without distant metastasis and with at least six weeks of radiation. The primary exposure was the duration of radiation therapy (DRT), and the primary outcome was death. We estimated the association between DRT and 5-year overall survival (OS) using Kaplan-Meier curves and hazard ratios (HRs) with Cox proportional hazard regression. RESULTS: In both primary (definitive) and adjuvant (post-surgical) radiation settings, increased DRT results in decreased survival. In the primary radiation cohort, 5-year OS was 59.7% [59.1%-60.3%] among those with 47-53 days DRT, which decreased significantly with each subsequent week to completion (81+ days: 38.4% [36.2%-40.7%]). In the surgical cohort, survival decreased 16.5% when DRT extended beyond 75 days (40-46 days: 68.2% [67.3%-69.1%] vs. 75+ days: 53.3% [50.1%-56.7%]). Multivariate analyses showed increased hazard of death with increased DRT (primary radiation: 81+ days HR: 1.69 [1.58-1.81]); surgical: 75+ days HR: 1.61 [1.37-1.88]), with effects intensifying when restricting to those receiving full-dose radiation. CONCLUSION: A prolonged DRT was associated with worse OS in head and neck cancer. Radiation treatment delays of even a week lead to a significant survival disadvantage. DRT had a stronger association with survival than time to initiation of postoperative adjuvant radiotherapy.

Extranodal extension is a strong prognosticator in HPV-positive oropharyngeal squamous cell carcinoma.

OBJECTIVE: To comprehensively examine the prognostic significance of extranodal extension (ENE) in human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-positive OPSCC). METHODS: Retrospective cohort of cases diagnosed with HPV-positive OPSCC from 2010 to 2015 in the National Cancer Database. Inclusion of all OPSCC HPV-positive cases with appropriate International Classification of Diseases-0-3 codes that received surgery with a neck dissection. Univariate and multivariable analyses were conducted. Hazard ratios (HR) for the independent effects of ENE and N stage on overall survival were estimated by Cox proportional hazards regression. RESULTS: Cases that were ENE-negative had the highest 5-year survival (92.6%; 95% confidence interval [CI]: 90.5%-94.7%). ENE-positive cases had the lowest 5-year survival (84.0%; 95% CI: 80.7%-87.4%). After adjusting for confounding variables, ENE-positivity was associated with almost twice the hazard of death (HR = 1.90; 95% CI: 1.35-2.67) compared to ENE-negative cases. Nodal (N) category 1, ENE-positive status was associated with an increased risk of death (HR = 1.88; 95% CI: 1.26-2.80) compared with N1, ENE-negative status. Compared to N1/ENE-negative cases, N2/ENE-positive cases had the poorest survival (HR: 2.93; 95% CI: 1.94-4.43). Both microscopic and macroscopic ENE were associated with worse outcomes compared to node-positive/ENE-negative status. CONCLUSION: The implementation of the American Joint Committee on Cancer 8th edition staging system provides a much-improved framework to develop and discuss treatment plans for HPV-positive OPSCC. We feel that careful consideration should be given to the importance of ENE in patients with HPV-positive OPSCC. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:939-945, 2020.

Predicting Hearing Loss After Radiotherapy and Cisplatin Chemotherapy in Patients With Head and Neck Cancer.

Importance: Accurate, accessible predictions of posttreatment hearing loss for patients with head and neck cancer prior to the initiation of treatment are a necessary part of informed patient decision-making. Objective: To develop a prediction model for postradiotherapy and/or post-cisplatin chemotherapy hearing loss for patients with head and neck cancer. Design, Setting, and Participants: A retrospective cohort study was conducted at a tertiary academic medical center among 242 patients (482 ears) with head and neck cancer who were treated with radiotherapy and/or cisplatin from October 1, 2014, to July 31, 2018, and had follow-up audiometric data available. Exposures: Radiotherapy and cisplatin chemotherapy. Main Outcomes and Measures: Patient hearing level, as measured by the mean of pure tone audiometry at 1, 2, and 4 kHz on completion of treatment. A multivariable mixed model for predicting the posttreatment pure tone average was developed using only information available to clinicians at the beginning of treatment. Results: A total of 242 patients (482 ears; 56 women and 186 men; mean [SD] age, 60 [10] years) were included in the analysis. All patients in the study received radiotherapy, and 105 (43.4%) received cisplatin chemotherapy. The mean (SD) total cumulative cisplatin dose was 298 (109) mg/m2. Patients' ears received a mean (SD) cochlear radiotherapy dose of 15 (13) Gy. The fixed-effects predictions from the predictive model agreed with 77% (95% CI, 73%-81%) of the variability in the posttreatment pure tone average. This predictive model also had a sensitivity of 80% and a specificity of 75% for predicting an observed posttreatment pure tone average greater than 35 dB (area under the receiver operating characteristic curve, 0.85). Conclusions and Relevance: To our knowledge, this study develops the first accurate prediction model of posttreatment hearing in patients with head and neck cancer that is feasible for use in the clinical setting before the initiation of treatment. This research confirms that exposure of the cochlea to cisplatin chemotherapy and radiotherapy is associated with hearing loss in patients with head and neck cancer. Finally, this research motivates future studies of ototoxic effects to better understand the adverse effects of head and neck cancer treatment.

Risk and Rate of Occult Contralateral Nodal Disease in Surgically Treated Patients With Human Papillomavirus-Related Squamous Cell Carcinoma of the Base of the Tongue.

Importance: The optimal treatment strategy for patients with human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) of the base of the tongue (BOT) has not been sufficiently studied. Objective: To investigate the rate of and risk factors for occult contralateral nodal disease in patients with HPV-related BOT OPSCC undergoing transoral surgery and bilateral neck dissections. Design, Setting, and Participants: This retrospective case series reviewed the medical records of patients with HPV-related BOT OPSCC who underwent transoral surgery and bilateral neck dissections from January 1, 2002, through December 31, 2018, at the tertiary care center of Washington University School of Medicine in St Louis. Patients had a median follow-up of 30.0 months (interquartile range, 11.0-60.4 months). Patients with recurrent disease or multiple synchronous OPSCC primary tumors were excluded for a total of 89 patients. Data were analyzed from January 1 through June 1, 2019. Main Outcomes and Measures: The primary outcome was the rate of contralateral occult nodal disease. Secondary outcomes were potential risk factors for contralateral occult nodal disease and regional recurrence rates. Results: Eighty-nine patients were included in the series, of whom 81 (91.0%) were men. The mean (SD) age was 60 (9) years. Overall, 34 patients (38.2%) had pathologic contralateral nodal metastases. Seventy patients had no clinical evidence of contralateral nodal disease. Of these 70, occult nodes were identified in 15 (21.4%). Risk of contralateral disease was higher when the primary tumor crossed midline (odds ratio, 6.23; 95% CI, 1.71-22.77). Of the 55 patients with no occult disease identified, only 2 (3.6%) received radiotherapy to the contralateral neck, and no regional recurrence of disease was noted. Conclusions and Relevance: Given the rate of occult contralateral nodal disease of 21.4%, it appears that contralateral elective neck dissection or radiotherapy should be recommended in patients with HPV-related BOT OPSCC. Patients with a pathologically negative result of contralateral neck dissection may not benefit from radiotherapy to that nodal basin. Future prospective investigations should evaluate functional and oncologic outcomes of contralateral elective neck dissection compared with elective radiotherapy in the contralateral neck for HPV-related BOT OPSCC.

nab-Paclitaxel-based induction chemotherapy followed by cisplatin and radiation therapy for human papillomavirus-unrelated head and neck squamous-cell carcinoma.

In patients with locally advanced human papillomavirus (HPV)-unrelated head and neck squamous-cell carcinoma (HNSCC), cisplatin and radiation therapy (CisRT) resulted in a local-regional recurrence (LRR) rate of 35%, progression-free survival (PFS) of 49%, and overall survival (OS) of 60%. We, and others, showed that nab-paclitaxel is an active agent in metastatic and locally advanced HNSCC. The aim of this report was to assess the efficacy of nab-paclitaxel-based induction chemotherapy and CisRT in HPV-unrelated HNSCC. We performed a retrospective single-institution analysis of patients treated with nab-paclitaxel-based chemotherapy and CisRT. Key inclusion criteria included stage III-IV HPV-unrelated HNSCC. Induction chemotherapy included nab-paclitaxel and cisplatin (AP), AP + 5-fluorouracil (APF), or APF + Cetuximab (APF-C). Endpoints included LRR, overall relapse, PFS, and OS. Thirty-eight patients were the subject of this analysis. Patient characteristics included median age 59 years (IQR: 54-64) and smoking history in 36 patients (95%). Primary tumor sites included larynx/hypopharynx (27), p16 negative oropharynx (10), and oral cavity (1). Most patients had bulky disease: 82% T3-4 (n = 31) and 74% N2b-3 (n = 28). Median follow-up was 44 months (IQR: 23-59). The three-year LRR rate was 16% (95% confidence interval [CI] 7-34) and the overall relapse rate was 22% (95% CI 11-41). The three-year PFS was 64% (95% CI 46-77) and OS was 72% (95% CI 54-84). Among patients with HPV-unrelated HNSCC, nab-paclitaxel-based induction chemotherapy and CisRT resulted in a lower-than-expected rate of LRR and more favorable PFS and OS compared to historical results with CisRT.

Eliminating Postoperative Radiation to the Pathologically Node-Negative Neck: Long-Term Results of a Prospective Phase II Study.

PURPOSE: The volume treated with postoperative radiation therapy (PORT) is a mediator of toxicity, and reduced volumes result in improved quality of life (QOL). In this phase II trial, treatment volumes were reduced by omitting PORT to the pathologically negative (PN0) neck in patients with primary head and neck squamous cell carcinoma. METHODS: Patients with head and neck squamous cell carcinoma who underwent surgical resection and neck dissection with a PN0 neck and high-risk features mandating PORT to the primary and/or involved neck were eligible. The primary end point was greater than 90% disease control in the unirradiated neck. QOL was evaluated using the MD Anderson Dysphagia Inventory and the University of Michigan patient-reported xerostomia questionnaire. RESULTS: Seventy-three patients were enrolled, and 72 were evaluable. Median age was 56 years (range, 31 to 81 years); 58 patients were male, and 47 (65%) had a smoking history. Sites included oral cavity (n = 14), oropharynx (n = 37), hypopharynx (n = 4), larynx (n = 16), and unknown primary tumor (n = 1). According to the American Joint Committee on Cancer Staging Manual (7th edition), 67 patients (93%) had stage III/IV disease, and 71% of tumors involved or crossed midline. No patient had contralateral neck PORT. In 17 patients (24%), only the primary site was treated. At a median follow-up of 53 months, two patients experienced treatment failure of the PN0 unirradiated neck; they also experienced treatment failure locally. Unirradiated neck control was 97% (95% CI, 93.4% to 100.0%). Five-year rates of local control, regional control, progression-free survival, and overall survival were 84%, 93%, 60%, and 64%, respectively. QOL measures were not significantly different from baseline at 12 and 24 months post-PORT (P > .05). CONCLUSION: Eliminating PORT to the PN0 neck resulted in excellent control rates in the unirradiated neck without long-term adverse effects on global QOL.

Timing of Postoperative Radiotherapy in Surgically Treated HPV-Positive Oropharyngeal Squamous Cell Carcinoma.

OBJECTIVE: Optimal timing of postoperative radiotherapy (PORT) remains understudied in human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma. Objectives are to determine if delays between surgery and radiotherapy, breaks during radiotherapy, disease, or patient factors are associated with recurrence or survival decrements in HPV-related disease. DESIGN: Retrospective review. SETTING: Academic medical center. SUBJECTS: A total of 240 cases of HPV-positive oropharyngeal squamous cell carcinoma from 2000 to 2016. METHODS: Patient and tumor characteristics (American Joint Committee on Cancer, eighth edition), delays to radiation initiation, and breaks during radiation were recorded. Overall survival (OS) and recurrence-free survival (RFS) were analyzed. RESULTS: RFS and OS were not significantly affected by delays to PORT >6 weeks or by treatment intervals >100 days (surgery to PORT completion). Breaks during PORT significantly imparted an OS detriment (hazard ratio [HR], 2.4; 95% CI, 1.2-4.8). Advanced-stage disease was significantly associated with reduced RFS and OS. Subgroup analysis of stage I versus stage II/III disease found that >6 weeks to PORT initiation and treatment intervals >100 days did not significantly decrease RFS or OS in either stage group. Advanced-stage disease was significantly associated with worsened OS (HR, 6.6; 95% CI, 2.3-19.1) and RFS (HR, 5.3; 95% CI, 1.5-18.4). Breaks during PORT significantly reduced RFS (HR, 3.6; 95% CI, 1.2-10.8) and OS (HR, 3.2; 95% CI, 1.2-9.0) in the stage II/III subset. CONCLUSION: Delays to radiotherapy initiation and prolonged treatment time did not affect recurrence or survival in HPV-related oropharyngeal disease. Locoregionally advanced disease was consistently associated with worse outcomes. Breaks during PORT may affect recurrence and survival, although larger studies are needed to confirm this finding.

Radiation therapy dose de-escalation compared to standard dose radiation therapy in definitive treatment of HPV-positive oropharyngeal squamous cell carcinoma.

BACKGROUND: Despite existing evidence that human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) has a favorable prognosis compared to HPV-negative OPSCC, randomized studies have yet to report the effect of de-escalating radiation therapy (RT) dose for definitive treatment. The aim of this study was to assess the effectiveness of dose de-escalated RT (DDRT) vs. standard dose RT (SDRT) in patients with HPV-positive OPSCC. METHODS: This was an observational study using the National Cancer Database (Year 2010-2014) to identify patients who had HPV-positive OPSCC and were treated with definitive RT or chemo-RT. Patients undergoing surgery were excluded. Patients receiving ≥50 Gy, but <66 Gy were categorized as receiving DDRT. Patients receiving ≥66 Gy were categorized as receiving SDRT. Inverse probability of treatment weighting (IPTW) using propensity scores was used to balance the two groups. Kaplan-Meier analysis was used to estimate overall survival (OS). Subset analyses in patients receiving RT alone and concurrent chemo-RT were also performed. Multivariable Cox proportional hazards modeling was used to evaluate factors associated with OS. RESULTS: 759 patients with HPV-positive OPSCC were identified: 104 received DDRT and 655 received SDRT. The median follow-up was 30.5 (2.4-81.4) months. After IPTW-adjusted analysis, there was no difference in the 3-yr OS between the two groups (82.2% vs. 79.3%; P = 0.85). In the subset of patients receiving concurrent chemoradiotherapy, IPTW-adjusted analysis also did not show a difference in the 3-yr OS between the two groups (83.1% vs. 79.6%; P = 0.83). On multivariable analysis, DDRT was not associated with an inferior OS (HR 0.88; 95% CI, 0.53-1.47; P = 0.63). CONCLUSIONS: In this study, DDRT was not associated with an inferior OS compared to SDRT in patients with HPV-positive OPSCC. Randomized clinical trials to address DDRT in this patient population are currently ongoing.