Modification of Pathological Nodal Classification for pT1b Esophageal Squamous Cell Carcinoma With Lymphovascular Invasion: Over 10-Year Experience

Background

Lymphovascular invasion (LVI) adversely affects the survival of pT1b esophageal squamous cell carcinoma (ESCC). It is hypothesized that a modified stage classification of pT1b ESCC based on LVI may facilitate multidisciplinary therapy in LVI-positive patients.

Aims

The study aims to investigate the impact of LVI on pathological nodal classification for pT1b ESCC.

Methods and Results

Surgically resected pT1b ESCC patients in Sun Yat-sen University Cancer Center between 2008 and 2018 were retrospectively reviewed. Tumor sections were re-assessed for LVI by gastrointestinal pathologists. The associations between patient survival and LVI were evaluated by the Log-rank method. A multivariate Cox regression model was applied to identify the impact of LVI on survival. Prognostic performance was assessed by Harrell's C-index. A total of 424 cases with the pT1b stage were included. The risk of LVI was significantly higher in patients with nodal positive status (p < 0.001) and larger tumor size (p = 0.033). The 5-year OS for LVI+ patients were 50.3% versus 78.0% for LVI− (p < 0.001). Multivariable analyses suggested that LVI (p = 0.021) and pN (p = 0.016) stages were two independent adverse prognostic factors in pT1b patients. When classifying LVI+ as an independent subgroup into the pN category, the modified pN staging system demonstrated a superior prognostic performance (p < 0.001).

Conclusion

Tumors with LVI should be defined as a separate subclassification to accurately classify the prognostic category in pT1b patients. Further studies are required to investigate multidisciplinary therapies for LVI+ pT1b patients.