Efficacy and safety of photodynamic therapy using an ultra-thin endoscope for local failure with esophageal stenosis after chemoradiotherapy for esophageal cancer.

backgroundPhotodynamic therapy (PDT) is a salvage endoscopic treatment option for local failure after chemoradiotherapy for esophageal squamous cell carcinoma (ESCC). PDT is usually performed using ordinary-sized conventional endoscopes (CEs); however, some patients with local failure have esophageal stenosis caused by chemoradiotherapy or endoscopic resection. In such cases, an ultra-thin endoscope (UTE) is sometimes used, but the efficacy and safety of PDT performed with UTEs (UTE-PDT) remain unclear. In this study, we compared the treatment outcomes of UTE-PDT with those of PDT using CEs (CE-PDT).

methodsThis retrospective study analyzed patients who underwent talaporfin sodium-based PDT for histologically confirmed local ESCC failure between October 2015 and June 2022. Short-term outcomes, including the local complete response (L-CR) rate and adverse events, were compared between UTE-PDT and CE-PDT.

resultsIn total, eight patients underwent UTE-PDT and 81 underwent CE-PDT. L-CR rates were 50.0% and 59.3% for the UTE-PDT and CE-PDT groups, respectively. The L-CR rates for lesions ≤ 20 mm were 50.0% (4/8) and 63.4% (45/71) in the UTE-PDT and CE-PDT groups, and for cT1 lesions, they were 57.1% (4/7) and 63.2% (43/68), respectively. Adverse events included esophageal pain (12.5% and 39.5%) and esophageal stenosis (12.5% and 4.9%) in the UTE-PDT and CE-PDT groups, respectively; however, all were grade ≤ 2.

conclusionsUTE-PDT for local failure after chemoradiotherapy for ESCC showed short-term outcomes that did not differ substantially from those of CE-PDT and may represent a potential therapeutic option for patients with no alternative treatment options.