BACKGROUND: Definitive chemoradiotherapy (dCRT) using cisplatin plus 5fluorouracil (CF) with radiation is considered the standard treatment for unresectable locally advanced T4 esophageal squamous cell carcinoma (ESCC). Recently, induction chemotherapy has received attention as an effective treatment strategy. CASE SUMMARY: We report a successful case of a 59-year-old female with unresectable locally advanced T4 ESCC treated by two additional courses of chemotherapy with CF after induction chemotherapy with docetaxel, cisplatin and fluorouracil (DCF) followed by dCRT. Initial esophagogastroduodenoscopy (EGD) detected a type 2 advanced lesion located on the middle part of the esophagus, with stenosis. Computed tomography detected the primary tumor with suspected invasion of the left bronchus and 90° of direct contact with the aorta, and upper mediastinal lymph node metastasis. Pathological findings from biopsy revealed squamous cell carcinoma. We initially performed induction chemotherapy using three courses of DCF, but the lesion was still evaluated unresectable after DCF chemotherapy. Therefore, we subsequently performed dCRT treatment (CF and radiation). After dCRT, prominent reduction of the primary tumor was recognized but a residual tumor with ulceration was detected by EGD. Since the patient had some surgical risk, we performed two additional courses of CF and achieved a clinically complete response. After 14 mo from last administration of CF chemotherapy, recurrence has not been detected by computed tomography and EGD, and biopsy from the scar formation has revealed no cancer cells. CONCLUSION: We report successful case with tumor remnants even after DCF and subsequent dCRT, for whom a complete response was finally achieved with two additional courses of CF chemotherapy. Additional CF chemotherapy could be one radical treatment option for residual ESCC after treatment with induction DCF followed by dCRT to avoid salvage surgery, especially for high-risk patients.