Tumour necrosis factor-α expression is associated with increased severity of periprosthetic breast capsular...

The pathogenesis of periprosthetic capsular contracture following breast implant surgery is unclear. The aim of this study was to identify the expression of tumour necrosis factor-α (TNF-α), collagen type III α(1) (COL3A1), transforming growth factor-β(1) (TGF-β(1)) and connective tissue growth factor (CTGF) in different Baker grades of breast capsular contracture.

Seven periprosthetic breast capsule specimens were collected from 6 patients. TNF-α, COL3A1, TGF-β(1) and CTGF gene expression were analysed using real-time quantitative polymerase chain reaction. Immunohistolocalisation of TNF-α was performed on paraffin-embedded sections. Significant correlations were analysed using the Pearson correlation coefficient.

TNF-α expression was associated with increased Baker grade of capsular contracture (Pearson correlation, r = 0.558; p = 0.02). COL3A1 gene expression was reduced with increasing severity of contracture (r = -0.490; p = 0.05). There were no significant correlations between TGF-β(1) and CTGF expression with Baker grade. Positive TNF-α staining in breast capsules was localised to fibroblasts, macrophages, and extracellularly close to the prosthesis.

The increased expression of TNF-α may play a key role in the inflammatory response associated with capsular contracture. The corresponding decrease in COL3A1 may contribute to the change in capsular physical properties seen in capsular contracture.