Programmed death-1 ligands and tumor infiltrating T lymphocytes in primary and lymph node metastasis of esophageal cancer patients.

Neoadjuvant chemotherapy (NAC) is administered to many patients with esophageal squamous cell carcinoma (ESCC) prior to surgery, but it is also true that some of these patients demonstrated no response to the therapy following surgery. In addition, the prognosis of advanced case such as ESCC patients with lymph node metastasis has remained relatively low. Programmed death ligand-1 (PD-L1) in conjunction with tumor-infiltrating lymphocytes (TILs) has been studied as a potential mechanism of "immune escape" in several human malignancies. Therefore, in this study, we studied PD-L1 status in carcinoma cells and forkhead box protein 3 (FOXP3) and CD8 status among TILs in the residual tumors of primary and metastatic sites following NAC. We also studied the association of these factors with the clinicopathological findings in 44 patients with ESCC harboring lymph node metastasis. There was discordance in the pathological response to chemotherapy between the primary tumor and lymph node metastasis, and histologically identified resistance to NAC in lymph node metastases tended to be correlated with an adverse clinical outcome (P = 0.0765) than resistance in the primary tumor. Both univariate and multivariate analyses for disease-specific survival (DSS) revealed that the PD-L1 status of carcinoma cells in metastatic lymph nodes and a higher FOXP3/CD8 ratio in the primary tumor were both significantly correlated with an eventual adverse clinical outcome of the patients (P = 0.0178, P = 0.0463, respectively). These results all indicated that the PD-L1 status of carcinoma cells in metastatic lymph nodes and the FOXP3/CD8 ratio in primary tumors could predict eventual clinical outcomes in ESCC patients with NAC.

Residual carcinoma cells after chemoradiotherapy for esophageal squamous cell carcinoma patients: striving toward appropriate judgment of biopsy.

In esophageal squamous cell carcinoma (ESCC) patients who are treated with chemoradiotherapy (CRT), identification of the presence or absence of residual or recurrent carcinoma is usually pivotal in their clinical management. In addition, the extent of carcinoma invasion into the esophageal wall could determine the clinical outcome of these patients following CRT. Therefore, in this study, we evaluated the response to CRT both macroscopically and histologically in a consecutive series of 42 ESCC patients receiving neoadjuvant chemoradiotherapy following curative esophageal resection at Tohoku University Hospital between August 2011 and December 2012. The histological grading of tumor regression was as follows: grade 3, markedly effective (no viable residual tumor cells); grade 2, moderately effective (residual tumor cells in less than one-third of the tumor); grade 1, slightly effective (1b, residual tumor cells in one-third to two-thirds of the tumor; 1a, residual tumor cells in more than two-thirds of the tumor); and grade 0, ineffective. In this study, we selected grade 2 and 1b cases because they might show a complete response with definitive CRT. We evaluated the presence of any residual in situ lesions and tumor depth in detail. The grading of tumor regression in primary sites was as follows: grade 3 (7 cases), grade 2 (16 cases), grade 1b (13 cases), and grade 1a (6 cases). The concordance rate between macroscopic and histopathological evaluation on the depth of the tumor was 40% (17/42). Among 29 cases (grade 2 and grade 1b), intraepithelial lesions were not detected in 17 cases, and tumor nests were not detected in the lamina propria mucosae in 9 cases. The results of this study highlight the difficulties of detecting residual carcinoma cells using conventional endoscopic biopsy in patients who have received CRT. Therefore, when residual cancer is clinically suspected in patients who have received CRT, the biopsy specimen should be obtained from the deep layer of the esophagus whenever possible. Additionally, close follow-up is required using positron emission tomography/computed tomography, endoscopy, and other radiological evaluations.