{Reference Type}: Case Reports {Title}: Pathologic complete response after photodynamic therapy combined with dose-reduction chemoradiotherapy in elderly patient with severe obstruction esophageal carcinoma: A case report. {Author}: Zhang M;Xu S;Sun Z;Qi R;Xu J;Shen H;Zhao J; {Journal}: Photodiagnosis Photodyn Ther {Volume}: 41 {Issue}: 0 {Year}: Mar 2023 {Factor}: 3.577 {DOI}: 10.1016/j.pdpdt.2023.103274 {Abstract}: Esophageal Carcinoma (EC) is one of the most aggressive gastrointestinal cancers. Advanced esophageal carcinoma is associated mainly with dysphagia which reduces the quality of life and leads to frail in patients even difficult to tolerate systemic treatments such as surgery and chemoradiotherapy. Moreover, chemoradiotherapy(CRT)cannot relieve dysphagia in a short time especially for the elderly patient with comorbidities. Here, we report a 76-year-old female patient diagnosed with severe obstructive esophageal squamous cell carcinoma (ESCC) that endoscope could not pass through. She was also complicated with bilateral interstitial pneumonia and moderate pulmonary ventilation dysfunction. The patient was unable to undergo surgery and radical CRT. After multidisciplinary team (MDT) discussion, we gave the patient photodynamic therapy (PDT) treatment firstly. The obstruction was significantly improved within 1 week and normal diet was resumed after 2 weeks. Four weeks later, considering bilateral interstitial pneumonia, concurrent dose-reduction chemoradiotherapy was given for esophageal lesions and abdominal metastatic lymph nodes. There was no recurrence and progression in the esophagus and abdominal lymph nodes until now and the biopsy of the primary esophageal lesion showed pathologic complete response. Now, the patient is still under regular follow-up.