The impact of tissue block sampling on the detection of p53 signatures in fallopian tubes from women with BRCA 1 or 2 mutations and controls
Modern Pathology, 10/04/2010
Mehra KK et al. – This study underscores the importance of systematic immunohistochemical examination of fallopian tubes when conducting epidemiological studies that compare the frequency of p53 signatures in different populations. Attention to this detail is critical when exploring risk factors germane to early serous carcinogenesis.
Methods- Initial section and 2 levels (100–200??m) from every block in BRCA+ (24) and control tubes (40) stained for p53
- Total of 17 (71%) BRCA+ and 20 (50%) control tubes p53 signature positive (P=0.12); 21 and 16% of all tissue blocks sectioned harbored signatures (P=0.29), and 76 and 67% found in fimbria
- In 49 and 32% of p53 signature positive cases in 2 groups, p53 signatures were not discovered until second or third round of sectioning
- 38 and 40% of BRCA+ and control subjects harbored p53 signatures in more than 1 focus in a single block
- In 1 case (BRCA+), highly atypical proliferation identified in 1 serial section
- p53 signatures more common than previously reported and frequency of detection increases as function of sectioning through tissue block, both in absolute frequency and in numbers of p53 signatures detected in a given block
