Higher-Dose Radiotherapy Adds No Benefit in Esophageal Cancer

Definitive chemoradiotherapy without surgery is an acceptable alternative treatment in esophageal cancer, especially for patients with squamous cell primaries. There is ongoing controversy about the role of escalating the dose of radiation therapy above 45 to 50.4 Gy for patients undergoing primary chemoradiotherapy without surgery.

Investigators now report results of the ARTDECO trial, an open-label randomized phase 3 trial in which patients with esophageal squamous cell carcinoma (SCC) or adenocarcinoma who were not considered surgical candidates or declined surgery were treated with definitive chemoradiotherapy without surgery at different radiation doses. Patients were randomized to 6 weekly carboplatin/paclitaxel treatments combined with either 28 fractions of 1.8 Gy radiotherapy five times a week to a total dose of 50.4 Gy, or the same radiotherapy with an integrated boost to the primary tumor in 2.2 Gy fractions to a total dose of 61.6 Gy.

Of 260 patients, median age was 70.5, 62% had squamous cancers, and 49% of tumors were in the mid or upper thorax. The most common reasons for nonsurgical treatment were medical unfitness (28%), proximal tumor location (20%), and extent of nodal spread (13%).

At a median follow-up of 50 months, local progression-free survival (PFS) at 3 years was not significantly different between the standard and experimental arms (71% and 73%; P=0.62), including in subsets with squamous cancer (75% and 79%) or adenocarcinoma (61% and 61%). At 3 years, there was also no significant difference between standard and experimental arms in overall PFS (33.1% and 25.4%) or overall survival (42% and 39%). Grade 5 toxicity from esophageal bleeding was numerically higher in the experimental arm (3 cases, vs. 1 case in the standard arm).