The addition of chemotherapy (CT) to radiation therapy (RT) improves survival rates among a subset of elderly head and neck cancer patients, specifically those ages 71 to 79 with low comorbidity scores and advanced disease stage, according to research presented at the 2016 Multidisciplinary Head and Neck Cancer Symposium.

Drawing on nationwide population-based data, the study demonstrated a survival benefit of chemoradiation therapy (CRT) similar to that for younger head and neck squamous cell carcinoma (HNSCC) patients among septuagenarians with limited comorbidity and later stage disease.

CRT did not predict survival improvement in patients age 80 and above or those with earlier stage disease or multiple comorbidities.

While previous research has demonstrated the efficacy of combining concomitant CT with RT to improve survival for HNSCC patients, this improvement has not been shown in patients older than 70 years.

In particular, a 2009 meta-analysis of 16,485 patients in 87 randomised trials found that benefits of CRT for locally-advanced HNSCC decreased with age and concluded no overall survival (OS) benefit for patients age 71 and above.

Patients in this age range totaled only four percent of the population in this meta-analysis, however, while individuals age 71 and above accounted for more than nine percent of the 2010 U.S. Census.

"Elderly patients have been underrepresented in prospective clinical trials that have defined standards of care for head and neck cancer," said Sana Karam, MD, PhD, an assistant professor of radiation oncology at the University of Colorado School of Medicine in Aurora, Colorado, and senior author on the study.

"Our study drew on nationwide data to assess more comprehensively how combined therapy impacts this population."

The authors queried the National Cancer Data Base (NCDB) for records of patients older than 70 years who were treated for non-metastatic oropharyngeal, laryngeal and hypopharyngeal cancers between 1998 and 2011.

The NCDB is a jointly-sponsored project of the American College of Surgeons and the American Cancer Society that aggregates data from more than 1,500 facilities accredited by the Commission on Cancer.

Cases were divided into two groups based on whether or not patients received CT concurrent with RT.

All patients received definitive RT (66.0-81.6 Gy in 1.2-2.0 Gy fractions), and concurrent chemoradiation was defined as beginning a course of CT within 14 days of RT start.

Sixty-eight percent of the patients received RT alone, and 32 percent received CRT.

Multivariate and propensity-score-matched analyses were used to compare OS outcomes between the cohorts, and researchers conducted recursive partitioning analysis based on OS to examine differences associated with age, Charlson comorbidity score, T-stage and N-stage.

Compared to RT alone, CRT was associated with improved survival following HNSCC in patients age 79 and younger (Hazard Ratio (HR), 0.80; p = 0.001), with comorbidity scores of zero or one (HR, 0.84; p = 0.002), and advanced disease stage (i.e., either T1-2/N2-3 or T3-4/N0-3 disease (HR, 0.77; p < 0.001).

Findings also demonstrated an OS benefit of CRT for patients treated with intensity modulated RT (HR, 0.76; p = 0.002).

Patients who did not see an OS benefit from CRT tended to be age 79 or older (HR, 0.93, p = 0.368), had a comorbidity score of two or greater (HR, 1.00, p = 0.992), presented with T-stage I or II disease (HR, 1.09, p = 0.448), or were treated with three-dimensional RT (HR, 1.02, p = 0.923).

Patients age 79 or older with multiple comorbidities trended toward worse OS with CRT, though the difference was only marginally significant (HR, 2.36; p = 0.080).

Findings may aid clinicians in discussing treatment options with their elderly HNSCC patients.

Moreover, results of this study could guide future prospective trials to confirm the benefit of multimodality treatment in elderly patients, not only for head and neck cancer but for other cancer sites, as well.

"Because the toxicity of concurrent chemoradiation is greater than radiation alone for definitive HNSCC treatment, many clinicians have reservations about offering CRT for elderly head and neck cancer patients," said Dr. Karam.

"However, in the era of improved radiation techniques, improved systemic therapy and better supportive care, we find that CRT does, in fact, improve survival for a large segment of this population."

Source: American Society For Radiation Oncology