Complex regional pain syndrome (CRPS) is a neuropathic pain disorder, characterized by persistent and severe pain after trauma or surgery. Diagnosis is mainly based on clinical signs and treatment is based on a multidisciplinary approaches, including non-pharmacological approaches and occupational therapy，pharmacotherapy and invasive therapeutics. This article reviewed the current advice of diagnosis and treatment of CRPS.

Objective:To observe the long-term efficacy and late adverse reactions of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for mediastinal lymph node recurrence after radical surgery for esophageal squamous cell carcinoma (ESCC).Methods:A total of 20 ESCC patients with mediastinal lymph node recurrence (≤5) after radical surgery admitted to Department of Radiotherapy, Shanghai Ruijin Hospital between June 2019 and December 2021 were enrolled in this prospective study. Among them, 10 patients were enrolled in phase I study and 10 patients in phase II study. Four, 3 and 13 patients received three different doses of SIB-IMRT at 58.8 Gy/28 fractions, 64.4 Gy/28 fractions and 70.0 Gy/28 fractions for recurrent lesions, respectively. The overall survival (OS) rate, local control rate (LCR) and progression-free survival (PFS) were calculated by Kaplan-Meier analysis. Adverse reactions were also analyzed.Results:The most common sites of recurrence were 2R and 4 L, accounting for 35% and 25%, respectively. The median follow-up time was 32 months. For patients who received salvage chemoradiation after relapse, the 1-, 2- and 3-year OS rates were 100%, 88% and 78%, the 1-, 2- and 3-year PFS rates were 85%, 78% and 78%, respectively. The most common hematological toxicities were leukocytopenia and anemia. The most common nonhematological toxicity was esophagitis. However, no grade 3 or above esophagitis, pneumonia and cardiotoxicity were found. Three patients who received SIB-IMRT at 58.8 Gy/28 fractions died of distant metastases at 2 years after treatment, and 1 patient who received SIB-IMRT at 70.0 Gy/28 fractions died of distant metastases at 16 months after treatment.Conclusion:Salvage chemoradiotherapy using SIB-IMRT is efficacious and safe for mediastinal lymph node recurrence in ESCC patients after radical resection.