Source: www.medpagetoday.com
Author: Ed Susman, Contributing Writer, MedPage Today

In selected patients with nasopharyngeal carcinoma, radiation alone may do as much against the disease as the combination of radiation and chemotherapy but with fewer adverse effects, researchers suggested here.

About 90% of patients who received radiation alone achieved failure-free survival at 3 years versus 91.9% of patients treated with both radiation and chemotherapy (P=0.86; non-inferiority P<0.001), reported Jun Ma, MD, PhD, of Sun Yat-sen University Cancer Center in Guangzhou, China.

In his virtual oral presentation at the annual meeting of the American Society of Clinical Oncology, Ma also reported that 98.2% of patients treated with radiation alone survived to 3 years compared with 98.6% of patients who got both radiation and chemotherapy (P=0.30).

The multifaceted subgroup analysis almost entirely favored treatment with alone. There was no difference in distant metastasis-free survival (95% in both arms) or local-regional recurrence-free survival, with both arms hovering in the 90-92% level.

And patients treated with both therapeutic modes paid a price in adverse events (AEs), Ma reported, noting that grade 3 to 4 mucositis was observed in 18.9% of patients on chemoradiation but in just 9.7% of those on radiation therapy alone.

A similar story in AEs was observed for leukopenia, neutropenia, nausea (0.6% vs 13% grade 3-4), vomiting (1.2% vs 14.8%), anorexia (4.8% vs 29%), and weight loss.

That differential in AEs was reflected in quality of life measurements, with better scores in the radiation-only group as far as their global health status, social functioning, fatigue, nausea and vomiting, pain, insomnia, appetite loss and constipation were concerned.

This multicenter, open-label phase III trial was performed at four hospitals in China. Ma and colleagues enrolled patients ages 18 to 65 years, with histologically confirmed, stage T1-2N1/T2-3N0M0 nasopharyngeal carcinoma. They were required to have a Karnofsky performance status score of at least 70 and were randomized 1:1 to receive either concurrent chemoradiotherapy (a regimen of cisplatin at 100 mg/m² on days 1, 22, and 43) or radiotherapy alone.

From November 11, 2015 to August 4, 2020, the researchers assigned 172 individuals to radiotherapy alone, and 169 other patients to radiotherapy plus chemotherapy.

“The take home message for this study,” Ma said, “is that patients in the intensity-modulated radiation therapy era who have stage II and T3N0 nasopharyngeal carcinoma with small lymph nodes as well as low Epstein-Barr Virus DNA are at low risk for recurrence. This low-risk subgroup can be safety treated with intensity-modulated radiation therapy alone instead of cisplatin-based chemoradiotherapy.”

He said the benefits of radiation treatment alone offer non-inferior survival and disease control, reduced toxicities, and improved quality of life.

In commenting on the trial, James Bonner, MD, chairman of radiation oncology at the University of Alabama at Birmingham, told MedPage Today: “Many of these stage II nasopharyngeal patients would receive chemoradiotherapy in the U.S. These studies from China are relevant for Epstein-Barr virus-positive tumors, which is becoming more common in the U.S. Therefore, these findings do suggest that some of these patients can avoid chemotherapy and the associated side effects.”