Results of a phase 3 study showed that local disease control was not improved in patients with inoperable, nonmetastatic esophageal cancer receiving standard chemoradiation therapy when a radiation therapy (RT) boost to the tumor was added. The findings from this study will be presented at the 2020 Gastrointestinal Cancers Symposium in San Francisco, California.
This randomized controlled phase 3 study (ARTDECO; Clinical trial information: NL38343.018.11) was designed to evaluate the efficacy and safety of dose-escalated RT (HD) compared with standard-dose RT (SD) in patients with clinical stage T2 to T4, N0 to N3, M0 esophageal cancer receiving platinum-based chemoradiation therapy.
Patients, stratified according to disease histology, were randomly assigned to receive chemotherapy with carboplatin and paclitaxel in conjunction with either SD RT (ie, 50.4 Gy/1.8 Gy/5.5 weeks) or SD RT plus an integrated boost of 0.4 Gy per fraction, for a total of 61.6 Gy, to the primary tumor (HD).
The primary study endpoint was local progression-free survival (LPFS), with secondary study endpoints including locoregional progression-free survival (LRPFS), overall survival (OS), and toxicity.
Of the 260 patients included in the study, the most common reasons for inoperability included proximal location and patient preference (44%), as well as comorbidity (30%). Disease histology was characterized by squamous cell carcinoma (SCC) and adenocarcinoma (AC) in 61% and 39% of patients, respectively. Most of the study participants completed RT (94%) and at least 5 cycles of chemotherapy (85%).
At a median follow-up of 45 months, the 3-year rate of LPFS was 70% and 76% in the SD and HD arms, respectively, although this difference was not statistically significant. When these results were considered according to disease histology subgroup, the 3-year LPFS rate was 74% (SD arm) and 81% (HD) for patients with SCC, and 62% (SD arm) and 65% (HD arm) for patients with AC, with no significant differences observed.
Similarly, 3-year LRPFS rates of 53% (SD arm) and 63% (HD arm) in the overall group were not significantly different (P =.08). Rates of 1-year PFS were 60% and 50% for patients with SCC and AC, respectively (P =.5). Three-year OS rates were 41% for those receiving SD and 40% for patients treated with HD.
Regarding safety, rates of grade 5 adverse events were 4% in the SD arm and 10% in the HD arm.
In their concluding remarks, the study authors noted that toxicity was higher in the HD arm while no significant changes in rates of local control or OS were observed between the 2 study arms.
Disclosures: Some of the study authors disclosed financial relationships with pharmaceutical companies. For a full list of disclosures, please refer to the study abstract.
Maarten CCM, Hulshof DG, Rozema T, et al. A randomized controlled phase III multicenter study on dose escalation in definitive chemoradiation for patients with locally advanced esophageal cancer: ARTDECO study. J Clin Oncol. 2020;38(suppl 4): Abstract 281.
This article originally appeared on Cancer Therapy Advisor