Association of local complete response with prognosis after salvage photodynamic therapy for esophageal squamous cell carcinoma.

Abstract

Photodynamic therapy (PDT) is an effective salvage endoscopic treatment for local failure at the primary site after chemoradiotherapy (CRT) in esophageal cancer patients. However, the contribution of local control by salvage PDT to the prognosis is unclear. We investigated whether complete response at primary site by salvage PDT could improve the prognosis. Between January 2008 and March 2016, 34 patients received salvage PDT for local failure of esophageal cancer limited to stage T1-2 after definitive CRT or radiotherapy. Local complete response (L-CR) rate, adverse events, overall survival (OS), and progression-free survival (PFS) were assessed retrospectively. Local complete response rates after PDT were 68% (23/34; 95%CI, 50-83%) in all patients: 81% (17/21; 95%CI, 58-95%) for stage T1 and 46% (6/13; 95%CI, 19-75%) for stage T2 patients. Grade 3 esophageal stricture occurred in one patient. The median follow-up was 26.0months (range, 3.7-93.6months); 21 patients died. The median survival times were 54.3months in patients who achieved L-CR after PDT (L-CR group) and 19.8months in those who did not (non-CR group). The 2-year OS rates were 79% (95%CI, 54-92%) in the L-CR group and 40% (95%CI, 11-68%) in the non-CR group (P=0.0389; log-rank test). The median PFS was 21.2months in the L-CR group and 1.9months in the non-CR group (P<0.001; log-rank test). Achieving L-CR by salvage PDT for local failure after CRT in esophageal cancer was associated with good prognosis.