Daly, Mackenzie

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 (7 th 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.

ObjectiveOptimal 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.DesignRetrospective review.SettingAcademic medical center.SubjectsA total of 240 cases of HPV‐positive oropharyngeal squamous cell carcinoma from 2000 to 2016.MethodsPatient 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.ResultsRFS 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.ConclusionDelays 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.