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

[BACKGROUND] 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.

[METHODS] 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.

[RESULTS] 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.

[CONCLUSION] 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.