Pathogenesis of esophageal squamous cell carcinoma with lymphoid stroma

Background/Aims: Lymphocyte infiltration in esophageal cancer, especially when beneath intraepithelial carcinoma, is frequently seen. However, cases of esophageal cancer with a dense stromal infiltration of lymphocytes are rare and the pathogenesis of such cases has yet to be clearly demonstrated. The objective of this study is to clarify its pathogenesis. Methodology: Four cases of esophageal squamous cell carcinoma with lymphoid stroma were investigated by immunohistochemical staining for the detection of Epstein-Barr virus, human papillomavirus, human leukocyte antigen-DR, as well as T and B cells in cancer tissue. Results: In these four cases, neither positive staining of Epstein-Barr virus nor human papillomavirus infection was detected. On the other hand, the expression of human leukocyte antigen-DR antigen was evident in all cases with dense T-cell infiltration in the tumor tissue and moderate B-cell infiltration around the tumor. Conclusions: The expression of human leukocyte antigen-DR antigen without Epstein-Barr virus or human papillomavirus infection could thus be one possible pathogenesis of patients demonstrating esophageal squamous cell carcinoma with a lymphoid stroma.