Evaluation of the Status of Intraparenchymal Plasma Cells in Terms of IgG4Expression in Patients Diagnosed With Idiopathic Granulomatous Mastitis

Idiopathic granulomatous mastitis (IGM) is a chronic inflammatory lesion thatmimics the clinical symptoms of carcinoma. Another type of chronic granulomatous mastitis is immunologicalmastitis, which is related to the infiltration of IgG4 plasma cells. This study aims to determine thestatus of IgG4 positive plasma cells in IGM samples.

This is an analytical-cross-sectional study. 46 women diagnosed with IGM wereselected for the study using census method. The percentage of IgG and IgG4 in plasma cells was determinedbased on immunohistochemical method. Age and type of surgery were also recorded. The datawas entered into SPSS software, version 22 and analyzed using statistical tests. P<0.05 were consideredstatistically significant.

The mean age of patients was 35.02±6.82 years. The mean percentage of IgG positive plasmacells among tissue inflammatory cells was 6923±23.42 and the mean percentage of IgG4 positive plasmacells was 23.39±22.33. Among infiltrated plasma cells, 1.89% were positive for IgG4 and the ratio of IgG4to IgG in plasma cells was 0.91. Based on the results of Pearson correlation test, a positive and significantcorrelation was found between the percentage of IgG4 and IgG in plasma cells (r=0.600, P=0.004).

A significant percentage of infiltrated plasma cells are IgG4 positive, which can play a role inthe development of IGM. Therefore, further investigation and comparison with immunological mastitisis recommended.