FA06.01: CLINICAL EFFECT OF NEOADJUVANT CHEMOTHERAPY OF ESOPHAGEAL SQUAMOUS CELL CARCINOMA FOR SUPERFICIAL PHARYNGEAL SQUAMOUS CELL CARCINOMA

Background Esophageal squamous cell carcinoma (ESCC) is often synchronously accompanied by pharyngeal squamous cell carcinoma (PSCC). However, the treatment strategies for these cancers have not been established. Neoadjuvant chemotherapy is the standard treatment for advanced ESCC and is also effective for PSCC patients. However, few studies have focused on the efficacy of systemic chemotherapy for patients with superficial PSCC. Methods We retrospectively examined 22 cases of superficial PSCC that occurred in 14 patients with ESCC who received neoadjuvant therapy between January 2011 and June 2017. Results Of the 14 patients, 13 (93%) were male, and the median age was 63.5 years (range: 35–74 years). The clinical stage of ESCC was II for 7, III for 5, and IVB for 2 (AJCC 8th staging system). The PSCC origin included the oropharynx in 9 lesions (40.9%) and the hypopharynx in 13 lesions (59.1%). Macroscopic type was classified as protruding (type1 or 0-I) for 2, superficial elevated (0-IIa) for 5, superficial flat (0-IIb) for 13, and superficial depressed (0-IIc) for 2. The estimated depth of invasion was EP in 12 lesions, SEP in 8 lesions, and MP in 2 lesions. FP regimen was administered to 11 patients in 15 lesions and DCF to 3 patients in 7 lesions. One patient had concurrent chemoradiotherapy. Chemotherapy for PSCC resulted in CR in 10 lesions (45.4%). In CR, 9 of 10 lesions were of superficial flat type. All non-CR lesions also had tumor regression. In the CR patients, 5 lesions(50%) had local recurrence, and the median duration until recurrence was 4 months (range: 4 to 17 months). Endoscopic resection(ER) for PSCC was performed in the 13 lesions after esophagectomy. The median duration after diagnosis was 7 months (range: 3 to 20 months). Conclusion Systemic chemotherapy of ESCC has tumor regression potential for superficial flat-type PSCC with clinical tumor invasion in EP or SEP. Although chemotherapy for PSCC results in non-CR, additional ER is quite effective. Because half of the CR lesions had recurrence, strict follow-up and observation of the pharynx are reasonable options for patients with ESCC. Disclosure All authors have declared no conflicts of interest.