Top Line: Can adaptive neoadjuvant therapy improve response for locally advanced esophageal cancer?
The Study: CALGB 80803 was a randomized, phase 2 study that sought to determine if an interim PET/CT could be used to modify the chemo used with neoadjuvant radiation in order to increase the pCR rate among patients who didn’t respond well to induction chemo. Patients had resectable T2+ or N+ esophageal or EG junction adenocarcinoma. They had initial PET, and the tumor had to have a maximum SUV of 5 or higher. They were randomized to induction FOLFOX6 or carbo/paclitaxel (CP) followed by an interim PET/CT. PET response was defined as ≥ 35% decrease in SUVmax, and those patients stayed with the same chemo during radiation. Nonresponders crossed over to the alternate chemo during radiation, which was 50.4 Gy in 28 fractions in both arms. Among 225 patients who had interim PET, there was no statistical difference in the SUV response rate between induction FOLFOX6 (65%) and CP (56%). The primary goal of the trial was to determine the pCR rate in PET nonresponders, which was 18-20% in both the FOLFOX6→ CP crossovers and the CP→ FOLFOX6 crossovers. This compares favorably to the expected 5% pCR rate for PET nonresponders with standard therapy. Surprisingly, the biggest difference in pCR rate was seen between FOLFOX6 PET-responders (40%) and CP PET-responders (14%).
TBL: In patients with esophageal adenocarcinoma who don’t PET-respond to induction chemo, a change in chemo regimen may improve their pathologic response rate to that seen in PET-responders. | Goodman, J Clin Oncol 2021