- Boosting the standard dose of radiation therapy did not improve survival outcomes significantly for patients with esophageal cancer receiving definitive chemoradiation.
Why this matters
- The current standard dose of around 50 Gy for local-regional control in esophageal cancer is relatively lower than the dose used for malignancies of the larynx, lung, bladder, and cervix.
- A previous dose-escalation trial comparing high-dose with standard-dose was prematurely terminated and the negative findings from the trial were never clearly understood.
- Patients with stage T2-4, N0-3, M0 carcinoma of the esophagus and not suitable for surgery (n=260) were randomly assigned to receive either a standard dose of 50.4 Gy or a high dose of 61.6 Gy.
- The chemotherapy regimen for both arms was six concurrent cycles of carboplatin and paclitaxel.
- The primary endpoint was local progression-free survival (PFS). Secondary endpoints included locoregional PFS, overall survival (OS), and toxicity.
- Funding: Dutch Cancer foundation KWF.
- The 3-year local PFS was 71% in the standard-dose group vs 73% in the high-dose group.
- The 3-year locoregional PFS was 53% in the standard-dose group vs 63% in the high-dose group.
- The 3-year OS in the standard-dose group and the high-dose group was 41% and 40%, respectively.
- The overall grade 4 and 5 toxicity was greater in the high-dose group vs the standard-dose group (grade 4: 13.6% vs 10.8%; grade 5: 8.5% vs 5%).
- Lower compliance rate in the high-dose group.
Dr Sara Lonardi, MD, from the Institute of Oncology Veneto, Italy, said: "From a theoretical perspective, a boost should work and we should have seen positive results. This study used more modern radiation treatments and modern regimens of chemotherapy."