The role of vascular invasion and lymphatic invasion in predicting recurrent thoracic oesophageal squamous cell carcinoma

Background Numerous studies have addressed lymphovascular invasion (LVI) in patients with thoracic oesophageal squamous cell carcinoma (ESCC); however, little is known about the individual roles of lymphatic invasion (LI) and vascular invasion (VI). We aimed to analyse the prognostic significance of LI and VI in patients with thoracic ESCC from a single centre. Methods This retrospective study included 396 patients with thoracic ESCC who underwent oesophagectomy and lymphadenectomy in our hospital. The relationship between LI, VI and the other clinical features was analysed, and disease-free survival (DFS) was calculated. Survival analysis was performed by univariate and multivariate statistics. Results Briefly, VI and LI were present in 25.8% (102 of 396) and 23.7% (94 of 396) of ESCC patients, respectively, with 9.15% patients presenting both LI and VI; the remaining patients did not present LI or VI. We found that LI was significantly associated with pN stage (P<0.001) and pTNM stage (P<0.001), and similar results were found in VI. Moreover, survival analysis showed that pT stage (P<0.001), pN stage (P=0.001), pTNM stage (p<0.001), VI (P=0.001) and LI (P<0.001) were associated with DFS in ESCC. Furthermore, multivariate analysis suggested that pT stage (RR=1.4, P =0.032), pN stage (RR=1.9, P<0.001) and LI (RR=1.5, P=0.008) were independent predictive factors for DFS. Finally, relapse was observed in 110 patients (lymph node metastasis, 78 and distant, 32) and 147 patients with cancer-related deaths. Subanalysis showed that LI-positive patients had higher lymph node metastasis, although there was no significant difference (32.1% vs. 15.6%, P=0.100). Conclusions LI and VI were common in ESCC; they were all survival predictors for patients with ESCC, and LI was independent. Patients with positive LI were more likely to suffer lymph node metastasis.