TP53 MUTATION ANALYSES ON BREAST CARCINOMAS - A STUDY OF PARAFFIN-EMBEDDED ARCHIVAL MATERIAL

The aim of this investigation was to examine the possibility of analys ing TP53 mutations in archival paraffin-embedded material with the con stant denaturant gel electrophoresis (CDGE) method. We extracted DNA f rom 193 archival primary breast carcinoma samples, diagnosed in 1981-8 3; further analysis was possible for 186 of these. TP53 mutations in e xons 5-8 were detected with CDGE in 30 samples (16.1%) and 17 of these mutations were confirmed by sequencing. Immunohistochemistry demonstr ated TP53 nuclear accumulation in 58 tumours (31%). A strong associati on between the presence of TP53 mutations and TP53 immunostaining was observed (P<0.001). Our mutation and immunohistochemistry results are in agreement with other findings based on fresh tumour tissue. TP53 ab normalities were significantly related to high S-phase fraction, low o estrogen receptor (ER) content and high tumour grade. Survival of pati ents with TP53 abnormalities, in the group as a whole, did not differ from patients with normal TP53. Our study did, however, show that pati ents with abnormal TP53 had a significantly shorter post-recurrence su rvival (P=0.005) than patients with normal TP53.