Long-term outcome of PDT for local failure after CRT or RT for oesophageal cancer

Background The long-term local control and effect of photodynamic therapy (PDT) using talaporfin sodium and a diode laser (talaporfin PDT) on overall survival (OS) for local failure after chemoradiotherapy (CRT) for esophageal cancer are unknown. Here, we present a 5-year survival analysis for talaporfin PDT. Methods This was a prospective follow-up analysis of an open-label, multicenter, phase 2 study of local failure after CRT or radiotherapy in patients who received talaporfin PDT. The primary endpoint was the overall OS. The secondary endpoints were progression-free survival (PFS), local progression-free survival (L-PFS) with local progression or recurrence and death as events, and local time to progression (L-TTP) with only local progression or recurrence as events. Results Between November 2012 and December 2013, 26 patients with oesophageal squamous cell carcinoma underwent talaporfin PDT. The baseline T stages were cT1 in 14 patients, cT2 in 6 patients, and cT3 in 6 patients. Pre-PDT T stages were cT1b for 19 and cT2 for 7 patients, and no lymph nodes or distant metastases were detected. At a median 6.8-year follow-up, the median OS and 5-year OS rates were 4.2 years (95% confidence interval [CI]: 1.6–7.3) and 40.6% (95% CI: 21.7–58.7), respectively. The median PFS and L-PFS were 1.1 and 2.1 years, respectively. The 5-year local progression-free rate was 84.9%. No treatment-related deaths occurred. Conclusion Talaporfin PDT for patients with oesophageal cancer with local failure after CRT can achieve long-term local complete response and long-term survival as a minimally invasive salvage treatment. Trial registration number UMIN000009184.