Features of lymph node metastasis and its effects on the prognosis of patients after radical operation for thoracic esophageal squamous cell cancer

Abstract

Objective To investigate the features of lymph node metastasis and its effects on the prognosis of patients after radical operation for thoracic esophageal squamous cell cancer, and investigate the reasonable postoperative adjuvant protocol. Methods Multivariate analysis of the clinical data of 204 patients was carried out by Spearman correlation analysis, Cox model and Kaplan-Meier method. Results The lymph node metastasis rate was 40.2% (82/204), and 166 out of 2193 dissected lymph nodes had metastasis with the rate of 7.57%. The analysis of related factors revealed that the invasion depth, tumor length and differentiation grade were significantly associated with the postoperative lymph node metastasis (χ2 = 17.466, 11.494, 6.767, P 0.05). Kaplan-Meier analysis showed that the 1-, 3-, 5-year survival rates of patients with < 4 lymph nodes metastasis were significantly higher than those with ≥4 lymph nodes metastasis (χ2=4.493, 4.494, 4.450, P < 0.05). The recurrence and metastasis were more often occurred in patients with lymph node metastasis compared with those without lymph node metastasis (r=-2.060, -4.296, P <0.05). Multivariate analysis confirmed that the pathological stage, tumor differentiation grade, and the postoperative adjuvant treatment were the independent prognostic factors. Conclusions The invasion depth, tumor length and differentiation grade are significantly associated with the postoperative lymph node metastasis. The lymph node metastasis state and the number of involved lymph nodes affect the prognosis of patients. Oral administration of 5-FU is benefit to the patients without lymph node metastasis. Key words: Esophageal cancer; Lymph node metastasis; Postoperative adjuvant treatment; Prognosis