ABSTRACT
Purpose To investigate the expression of the heavy chain of Ig protein, and observed it's value on differential diagnosis and significance on clinical pathological. Methods50 cases of non-Hodgkin's lymphoma (NHL) were collected as experimental group, including 30 cases of MALToma, 10 cases of follicular lymphoma (FL), and 10 cases of plasmacytoma(PC), 10 cases of reactive lymphoid hyperplasia (RLH) were collected as control group. The expression of IgM, IgA, IgD, IgG and IgE were detected by immunohistochemistry in the two groups. Results The lower positive rates of IgM, IgA were observed in the experimental group, MALToma, PC, and the lower positive rates of IgG, IgA were observed in FL (P＜ 0.05 ). The positive rate and expression intensity of IgM showed a rising trend (P＜ 0.05), and the positive rate of IgG show a downward trend (P＞0.05) in FL, MALToma, PC. There were three patterns of the heavy chain expression in the two groups: a single type expression, all negative expression, and a various type expression. The positive rates of a single type/ all negative heavy chain expression were 86.7％, 60％, 80％, 0 respectively in MALToma, FL, PC and RLH, the differences were statistically significant (P＜ 0.05 ). The positive rate of IgG was related to the type of tumor cells in MALToma(P＜ 0.05 ). Conclusion The expressions of IgM and IgG show a contrast trend in FL, MALToma, PC, and support that the most of MALToma and PC which come from postgerminal center experience class switch recombination, and frequently express a single IgG. A single type/all negative heavy chain expression is a frequent event in the MALToma, and it's helpful to the differential diagnosis of MALToma and RLH.