BACKGROUND: Photodynamic therapy (PDT) is a different type of laser treatment from Nd:YAG thermal ablation for palliation of dysphagia from esophageal cancer. METHODS: In this prospective, multicenter study, patients with advanced esophageal cancer were randomized to receive PDT with porfimer sodium and argon-pumped dye laser or Nd:YAG laser therapy. RESULTS: Two hundred thirty-six patients were randomized and 218 treated (PDT 110, Nd:YAG 108) at 24 centers. Improvement in dysphagia was equivalent between the two treatment groups. Objective tumor response was also equivalent at week 1, but at month 1 was 32% after PDT and 20% after Nd:YAG (p < 0.05). Nine complete tumor responses occurred after PDT and two after Nd:YAG. Trends for improved responses for PDT were seen in tumors located in the upper and lower third of the esophagus, in long tumors, and in patients who had prior therapy. More mild to moderate complications followed PDT, including sunburn in 19% of patients. Perforations from laser treatments or associated dilations occurred after PDT in 1%, Nd:YAG 7% (p < 0.05). Termination of laser sessions due to adverse events occurred in 3% with PDT and in 19% with Nd:YAG (p < 0.05). CONCLUSIONS: Photodynamic therapy with porfimer sodium has overall equal efficacy to Nd:YAG laser thermal ablation for palliation of dysphagia in esophageal cancer, and equal or better objective tumor response rate. Temporary photosensitivity is a limitation, but PDT is carried out with greater ease and is associated with fewer acute perforations than Nd:YAG laser therapy.