Comparison between immunocytochemical and polymerase chain reaction techniques for detection of oestrogen receptor and transforming growth factor beta in breast cancer

The utility of the polymerase chain reaction (PCR) as a technique for determining the expression of transforming growth factor beta (TGF-beta) and of the oestrogen receptor (ER) in clinical breast cancer tissue was examined. PCR analysis was compared with immunocytochemical assays for TGF-beta and for ER. Seventy confirmed breast carcinoma samples were analysed for ER using both techniques with a statistically highly significant concordance (P<0.001) between the two methods. Nineteen samples were observed to be ER positive and 46 samples were found to be ER negative by both techniques. Forty-eight samples were analysed for TGF-beta using both PCR and immunocytochemistry. Of the 24 samples observed to be positive for TGF-beta by immunocytochemistry, all were found to be positive for TGF-beta mRNA (PCR). Similarly, the 24 samples observed to be TGF-beta negative by immunocytochemistry were also negative for TGF-beta mRNA, indicating 100% specificity and 100% sensitivity of the PCR technique. PCR is therefore considered a viable technique for analysis of both ER and TGF-beta in small samples such as fine-needle aspirates.