Spindle cell carcinoma of the esophagus: A multicenter analysis in comparison with typical squamous cell carcinoma

This study conducted a retrospective multicenter analysis to investigate the clinicopathological features, optimal therapeutic strategy, and prognosis of spindle cell carcinoma (SpCC) of the esophagus.A total of 71 patients with esophageal SpCC from 3 large cancer centers in China were systematically analyzed. All patients received curative resection, 13 patients received adjuvant radiotherapy and 15 patients received adjuvant combination chemotherapy. Additionally, a total of 1852 patients with typical esophageal SCC (SCC) were selected as controls in this study.SpCC mostly presented as a polypoid appearance (66.2%), and the surrounding mucosa showed high-grade hyperplasia or superficial SCC in 31 cases (43.7%). Two patients even had extensive carcinoma in situ that spread to the resection margins. Patients in the SpCC group were more likely to present with stage I lesions compared with those in the typical SCC group (33.8% vs 8.0%, P < 0.001). Although the percentage of T1/2 lesions was higher in the SpCC group than in the typical SCC group (67.6% vs 29.7%, P < 0.001), both groups had similar rates of locoregional lymphatic metastases (45.1% vs 48.4%, P = 0.578). The median survival time and 5-year overall survival of the SpCC group was 43 months and 44.8%, respectively, higher than 37.5 months and 38.3%, respectively, for the typical SCC group (P = 0.044). In univariate analysis, the macroscopical type and pathological T, N, and TNM stages had a statistically significant impact on the prognosis of SpCC after curative resection. However, only the TNM stage (hazard ratio, 2.708; 95% confidence interval, 1.786-4.105, P < 0.001) was identified as an independent prognostic factor in multivariate analysis. The 5-year OS of SpCC in stages I (79.8%) and II (39.7%) were significantly longer than that of stages III/IV (16.2%) (P < 0.001 and P = 0.012). As those SpCC cases that received chemoradiotherapy were in more advanced stages, their prognosis was still worse than SpCC patients who did not receive chemoradiotherapy even after such treatment (P = 0.042, 0.010, respectively).SpCC shows a highly aggressive tendency of lymphatic spread, although it does not tend to infiltrate deeply into the esophageal wall. Compared with typical SCC that also underwent esophagectomy with extended lymphadenectomy, SpCC may achieve a better survival rate. Further investigation is warranted to examine the effect of postoperative chemoradiotherapy on the prognosis of SpCC.