# Treatment resistance factors associated with Talaporfin sodium photodynamic therapy for local control after chemoradiotherapy for esophageal cancer

## TL;DR

This study identifies esophageal stenosis before treatment as a factor that reduces the effectiveness of Talaporfin-PDT for esophageal cancer.

## Contribution

The study identifies esophageal stenosis as a novel predictor of resistance to Talaporfin-PDT for local control in esophageal cancer.

## Key findings

- The local complete response rate for Talaporfin-PDT was 65.5%.
- Patients with pre-treatment esophageal stenosis had significantly worse survival outcomes.
- Esophageal stenosis was an independent predictor of local treatment failure.

## Abstract

Talaporfin sodium photodynamic therapy (Talaporfin-PDT) shows a high local complete response (L-CR) rate for local failure after chemoradiotherapy in esophageal cancer; however, some patients do not achieve L-CR. We investigated the treatment resistance factors associated with Talaporfin-PDT for local control.

This study included 55 consecutive patients with ycT1-2 esophageal cancer who received Talaporfin-PDT. We investigated the L-CR rate, cumulative survival rate according to local effect, and treatment resistance factors associated with Talaporfin-PDT for local control using a multivariate logistic regression model.

The L-CR rate was 65.5% (95% confidence interval [CI]: 52.3–76.6). During the median follow-up of 17.8 months (range, 1.7–69.3), the 1-year overall survival (OS), progression-free survival (PFS), and disease-specific survival (DSS) rates were significantly higher in patients who achieved L-CR than in those who did not: 97.0% vs. 75.6% (P = 0.008), 64.6% vs. 0% (P < 0.001), and 97.0% vs. 85.7% (P = 0.005), respectively. In the multivariate logistic regression model, esophageal stenosis before Talaporfin-PDT was an independent predictor of local failure after Talaporfin-PDT (odds ratio: 5.626, 95% CI: 1.051–30.124, P = 0.044). The 1-year OS and DSS rates were significantly lower in patients with stenosis before Talaporfin-PDT than in those without: 75.0% vs. 92.4% (P = 0.015) and 85.7% vs. 94.6% (P = 0.015), respectively.

Esophageal stenosis before Talaporfin-PDT was associated with resistance to local control and poor survival. The indications for the use of Talaporfin-PDT in patients with stenosis should be considered carefully.

The online version contains supplementary material available at 10.1007/s10388-025-01177-w.