Prognostic status of p53 gene mutation in canine mammary carcinoma

Background: The p53 gene mutations have been associated with the developmen t of human breast and canine mammary neoplasms; breast carcinoma patients w ith alterations of p53 gene are considered to have a poor prognosis. Mammar y carcinoma represents the most common malignant tumor in female dogs. Howe ver, the prognostic significance of p53 gene mutation in the dog has been u nclear. Study design: The alteration in exons 5-8 of p53 gene in 69 canine mammary carcinomas were investigated by PCR-SSCP with direct sequence analy sis and statistically analyzed to compare with other clinicopathological pa rameters including age, neuter; tumor size, stage, histology, p53 expressio n, recurrence and death from carcinoma. Results: 12 out of 69 (17%) carcino mas showed p53 gene mutations. After a follow-up period of 30 months, multi variate regression analysis revealed that p53 gene mutation was only an ind ependent risk factor for increased risk of the recurrence and death from ma mmary carcinoma. Conclusion: The p53 gene alterations might contribute to t he prognostic status in canine mammary carcinomas, in a way comparable to t hat of human tumors.