Objective: To identify differences in survival of patients with pT1 esophageal cancer relating to depth of wall infiltration.
Background data: Histologic analysis of mucosal and submucosal infiltration in thirds has shown an increasing rate of lymph node metastases (LNM) according to the depth of wall infiltration in pT1 esophageal cancer.
Methods: One hundred seventy-one patients had transthoracic en bloc (n = 161) or transhiatal esophagectomy (n = 10) for pT1 esophageal cancer [121 adenocarcinomas (AC), 50 squamous cell carcinomas (SCC)]. The histologic analysis of the specimen comprised depth of wall penetration of the carcinoma in thirds of pT1a = mucosa (m1, m2, m3) or pT1b = submucosa (sm1, sm2, sm3) and number and infiltration of the resected lymph nodes.
Results: The rate of LNM was 0% for 70 mucosal carcinomas and 34% for 101 submucosal carcinomas (P = 0.001). For sm1, this rate was 13%, for sm2 19% and for sm3 56%. The 5-year survival rate (5Y-SR) was 82% for pN0 and 45% for pN+ patients (P < 0.001). There was no significant prognostic difference between AC and SCC (5Y-SR: 74% vs 71%). The 5Y-SR of the pT1a group was 87% compared with 66% for pT1b (P = 0.046). The 5-year survival rate for sm1 and sm2 were similar; sm1 + sm2 were together significantly better (80%) than sm3 (46%) (P = 0.008). In multivariate analysis, only sm3 was an independent prognostic factor (P = 0.01).
Conclusions: After esophagectomy, the prognosis of patients with sm1/sm2 infiltration is as good as for patients with mucosal carcinoma. Sm3 infiltration is the worst prognostic factor in pT1 esophageal cancer.