Nonsignificant Survival Benefit With Postoperative Radiation Therapy for Head and Neck Cancer at Academic Center vs Other Institutions
In a study reported in JAMA Otolaryngology Head & Neck Surgery, George et al evaluated radiation treatment characteristics and outcomes among head and neck squamous cell carcinoma patients receiving adjuvant external-beam radiation therapy at an academic center vs other institutions. Multivariate analysis showed no difference in survival, but the findings suggested a need for standardization of radiation therapy at nonacademic treatment facilities.
Study Details
The study was a retrospective cohort study involving 214 patients with primary head and neck squamous cell carcinoma treated with surgery at the University of California, San Francisco (UCSF), between January 2002 and January 2012 who received adjuvant radiation therapy either at UCSF (n = 91) or at other nonacademic center facilities (n = 123).
Patients treated at other facilities had higher mean age (62 vs 58 years, P = .02); lived further away from UCSF (mean, 96 vs 47 miles, P < .001); were more likely to be Hispanic (14% vs 4%, P = .03); were more likely to have laryngeal (20.5% vs 11%) and hypopharyngeal disease (4.1% vs 1.1%) and less likely to have oropharyngeal disease (11% vs 21%) or unknown primary (2.5% vs 8%; P = .02 for trend); and were more likely to have higher T stage (T4 in 54% vs 30%, P = .002 for trend), less likely to have never used tobacco (20% vs 43%, P = .001), more likely to have a greater pack-years history of smoking (> 30 in 39% vs 21%, P < .001 for trend).
Radiation Therapy Metrics
With regard to radiation therapy, patients treated at other facilities were less likely to receive intensity-modulated radiation therapy (52.5 vs 94%, P < .001); received a lower total dose (mean 57 vs 64 Gy, P < .001), fewer fractions (mean 29 vs 33, P = .01), and lower dose per fraction (mean, 1.9 vs 2.1 Gy, P < .001); and were more likely to have treatment delay (22% vs 10%, P < .001), breaks in therapy (16% vs 0%, P < .001), and early termination of therapy (10% vs 1%, P < .001) and less likely to receive a full course of therapy (75% vs 99%, P < .001).
Significant Benefit on Univariate Analysis
On univariate analysis, patients treated at the academic center had significantly greater overall survival (92% vs 83% at 1 year, 80.5% vs 64% at 2 years, 74% vs 54% at 3 years; P = .01), disease-specific survival (94% vs 84% at 1 year, 82% vs 66% at 2 years, 80% vs 55% at 3 years; P = .002), and locoregional control (91% vs 78.5%, P = .04).
Univariate analysis also showed that intensity-modulated radiation therapy use was associated with significantly improved overall survival, whereas Medicare and Medicaid insurance, heavy alcohol history, heavy tobacco use history, N2c vs N0 disease, and early termination of radiation therapy were significantly associated with poorer survival; oropharyngeal disease and receipt of a full course of radiation therapy had borderline significant associations with improved survival; and T4 vs T1 tumors had a borderline significant association with poorer survival.
Nonsignificant Benefit on Multivariate Analysis
On multivariate analysis adjusted for sex, tumor stage, American Joint Committee on Cancer stage, and smoking history, treatment at the academic center was associated with a nonsignificant overall survival benefit (hazard ratio [HR] = 0.75, P = .30) and was not an independent predictor of survival for any tumor site. The only factors consistently associated with poorer survival on multivariate analysis were heavy smoking history (HR = 1.8, P = .02, in same multivariate model) and T stage (P = .005–.02 in different models).
The investigators concluded: “Better oncologic outcomes were seen in the [academic center] group on univariate analysis, but these improved outcomes were not found on multivariate analysis. Important differences in [radiation therapy] metrics were noted for non-[academic center] treatment sites compared with [academic center] sites. Subgroup analysis by tumor site demonstrated persistent differences in treatment metrics. Standardization of adjuvant [head and neck squamous cell carcinoma] treatment according to national guidelines should be prioritized at non-[academic center] treatment facilities.”
Steven J. Wang, MD, of the University of California, San Francisco, is the corresponding author for the JAMA Otolaryngology Head & Neck Surgery article.
The study authors reported no potential conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
