Objective: Mutations in p53 exons 5-8 are found in 40-50% of breast carcinomas. We performed a retrospective analysis of p53 mutations in fluid-based, archival fine needle aspirates (FNAs) of breast masses to determine their potential diagnostic utility as breast tumor cell markers.
Study design: Residual, fluid-based, archival FNAs of 27 breast masses were retrospectively evaluated by polymerase chain reaction (PCR), single-strand conformational polymorphism analysis (SSCP) and sequencing for p53 exons 5-8. Results were compared with the morphologic diagnoses and genotyping of available excisional biopsy tissue.
Results: Six of the twenty-seven cases were found to have a clonal mutation in p53; all six mutated cases showed carcinoma on subsequent excisional biopsy. Definitive cytologic diagnosis of cancer had been possible in only four of the six cases. Identical mutations were found in the excised carcinomas in the five cases with available tissue. None of the 14 aspirates with benign cytology had detectable mutations in p53.
Conclusion: p53 Mutational analysis by PCR/SSCP/sequencing deserves to be critically studied as a diagnostic criterion in patients with indeterminate or suspicious cytology. Validation studies should be performed to test p53 mutations as molecular diagnostic markers in breast cytology specimens.