Oral Cancer Patients Face Worse Outcomes With Delayed Radiation Therapy

MONTREAL – Most patients in a Canadian cohort had prolonged times to postoperative radiation therapy, and those delays were associated with worse survival outcomes, a multicenter study showed.

Among 1,368 postsurgical patients with oral cavity squamous cell carcinoma, 80% waited more than 42 days to start postoperative radiation therapy (S-PORT). Delays in starting RT were tied to worse overall survival (OS) and disease-free survival (DFS), reported Gabriel Dayan, MD, of Centre Hospitalier de l'Université de Montréal (CHUM), in a presentation at the American Head & Neck Society (AHNS) annual meeting.

The median S-PORT was 56 days, and for these patients who waited >42 days, the 3-year OS was 66% versus 77% among those with an S-PORT within 42 days, per National Comprehensive Cancer Network (NCCN) guidelines (OR 1.75, 95% CI 1.27-2.42, P=0.005), according to Dayan, Apostolos Christopoulos, MD, MSc, also of CHUM, and colleagues in JAMA Otolaryngology-Head & Neck Surgery.

Dayan said the findings were in line with those from U.S. facilities, where getting patients to S-PORT in 42 days presents a challenge.

AHNS session co-moderator John Gleysteen, MD, of the University of Tennessee Health Science Center in Memphis, told MedPage Today that the NCCN guideline "is not too stringent a bar. Studies show that this is where we need to go for the most benefit for our patients."

Median radiation therapy interval (RTI) was 43 days (NCCN calls for 42-46 days), and 26% had a treatment time interval >46 days. A prolonged RTI (>46 days) was not linked with a worse 3-year OS at 67% versus 69% (≤46 days, OR 1.06, 95% CI 0.81-1.38).

While other factors were associated with OS -- age, Charlson Comorbidity Index (CCI), alcohol status, T category, N category, and institution -- prolonged S-PORT was still independently tied to OS (HR 1.39, 95% CI 1.07-1.80), the researchers said.

They explained that "our findings suggest that there is a pressing need to address delays in treatment for this patient population, as most patients could benefit from improvements to this metric." The researchers also noted that there "has been a shift toward a multimodal approach in the care of HNC [head and neck cancer], with several studies suggesting that multidisciplinary care leads to better cancer outcomes. However, this shift has not been able to translate into decreased mortality rates in national cancer statistics reports... this may be in part due to the fact that multidisciplinary care comes with the trade-off of prolonged treatment delays, which may contribute to poorer outcomes."

In an accompanying invited commentary, Evan Graboyes, MD, of the Medical University of South Carolina in Charleston, and Sue Yom, MD, PhD, MAS, of the University of California San Francisco, said that "it is clear that deep multidisciplinary engagement, meaningful partnerships around quality goals, and (inter) national communication and sharing of data such as that provided by Dayan et al. will be required for progress."

They added that "[a]s critical as it is for surgeons and radiation oncologists to partner together to understand and address delays in surgery-to-initiation of post-operative radiation therapy, the team of teams required to deliver timely adjuvant therapy is even larger. The inclusion of clinical colleagues in medical oncology, dentistry and oral maxillofacial surgery, pathology, nursing/navigation, social work, and hospital administration as well as researchers with expertise in health care delivery, cancer equity, and implementation science will no doubt enhance the quality and rigor of future initiatives in this area and accelerate its translation into meaningful improvements in patient outcomes."

The study was done in Canadian academic centers from 2005 to 2019, with analysis done in 2021. Median follow-up was 34 months. Participants (median age 61; 65% men) had oral cavity cancer (45% with oral tongue as the oral cavity subsite) and underwent surgery and adjuvant RT. The CCI was ≥4 in 41%. Also, 43% were current smokers (median 35 pack-years).

The researchers reported variations in treatment time intervals between institutions for S-PORT (longest median time 64 days vs shortest at 48 days) and RTI (44 days vs 40 days, respectively).

Study limitations included its retrospective design and the authors did not have data on race, ethnicity, and performance status. "Another limitation...is that it did not explore reasons for prolonged treatment times, which likely vary across institutions and include factors such as postoperative complications, nonadherence, delays in pathology reports, delays in consulting specialists (radiation oncology and medical oncology), or delays in preradiation dental extractions," according to the researchers.

AHNS session co-moderator Mathew Geltzeiler, MD, of Oregon Health & Science University in Portland, told MedPage Today that at his institution, "we have a nurse navigator who works to get patients and doctors on [a] schedule to get through S-PORT."

But "sometimes, the hold up can be the patients themselves," as they may have travel constraints, be reluctant to proceed after surgery, or have personal events or other factors that contribute to delays, he said.