DETECTION OF P53 GENE ABNORMALITY BY SEQUENCE-ANALYSIS OF ARCHIVAL PARAFFIN TISSUE - A COMPARISON WITH FRESH-FROZEN SPECIMENS

This parallel study was designed to compare the sensitivity and specif icity of detection of point mutations in fresh-frozen and formalin-fix ed, paraffin-embedded breast cancer tissue. Sequence analysis of exon 5 of p53 gene was performed on polymerase chain reaction-amplified DNA from 25 infiltrating ductal carcinomas of the breast. Four tumors sho wed mutations with identical base substitutions in their respective co dons of both frozen and paraffin-embedded specimens. We conclude that subtle genetic alterations can be detected in archival paraffin tissue with an accuracy comparable to that of fresh-frozen histologic sample s.