Lymphopenia predicts poor prognosis in patients with esophageal squamous cell carcinoma

Abstract

Lymphopenia is a useful predictive factor in several cancers. The aim of this study was to determine the prognostic value of lymphopenia in patients with esophageal squamous cell carcinoma (ESCC).A retrospective analysis of 307 consecutive patients who had undergone esophagectomy for ESCC was conducted. In our study, a lymphocyte count (LC) of fewer than 1.0 Giga/L was defined as lymphopenia. Kaplan-Meier method was used to calculate the cancer-specific survival (CSS). Cox regression analyses were performed to evaluate the prognostic factors. Receiver operating characteristic (ROC) curve was also plotted to verify the accuracy of LC for CSS prediction.The mean LC was 1.55 ± 0.64 Giga/L (range 0.4-3.7 Giga/L). The incidence of lymphopenia (LC < 1.0 Giga/L) was 16.6% (51/307). Patients with lymphopenia (LC < 1.0 Giga/L) had a significantly shorter 5-year CSS (21.6% vs 43.8%, P = 0.004). On multivariate analysis, lymphopenia (LC < 1.0 Giga/L) was an independent prognostic factor in patients with ESCC (P = 0.013). Lymphopenia had a hazard ratio (HR) of 1.579 [95% confidence interval (CI): 1.100-2.265] for CSS. ROC curve demonstrated that lymphopenia (LC < 1.0 Giga/L) predicts survival with a sensitivity of 86.2% and a specificity of 27.2%. Lymphopenia (LC < 1.0 Giga/L) is still an independent predictive factor for long-term survival in patients with ESCC.

FIGURE 1

The histogram of the LC (range 0.4–3.7 Giga/L).

FIGURE 2

Kaplan–Meier CSS curves stratified by LC. Patients with lymphopenia had a significantly shorter 5-year CSS (21.6% vs 43.8%, P = 0.004). HLC = high lymphocyte count, LLC = low lymphocyte count, M = month.

FIGURE 3

Kaplan–Meier CSS curves stratified by LC in patients with T stage and N stage. The 5-year CSS of patients with LC < 1.0 Giga/L was shorter than that of patients with LC ≥ 1.0 Giga/L in T1–2 group (26.1% vs 66.7%, P = 0.001, [A]) and T3–4a group (17.9% vs 33.1%, P = 0.043, [B]), respectively. However, no significant differences were found in N0 (45.0% vs 61.0%, P = 0.208, [C]) and N1–3 (6.5% vs 22.6%, P = 0.094, [D]) between patients with and without lymphopenia. HLC = high lymphocyte count, LLC = low lymphocyte count, M = month.

FIGURE 4

ROC curve for CSS prediction. A ROC curve plots the sensitivity on the y-axis against one minus the specificity on the x-axis. A diagonal line at 45°, known as the line of chance, would result from a test, which allocated subjects randomly. Each point on the ROC curve corresponds to a value of LC. The area under curve (AUC) was used as an estimation of diagnostic accuracy. Lymphopenia (LC < 1.0 Giga/L) predicts survival with a sensitivity of 86.2% and a specificity of 27.2%.