p53 and c-erbB-2 but not bcl-2 are predictive of metastasis-free survival in breast cancer patients receiving post-mastectomy adjuvant radiotherapy in Taiwan.
BACKGROUND
Patients with breast cancer often receive radiotherapy after mastectomy if they are at a high risk of local recurrence, but the prognosis varies among patients. We conducted a study to evaluate p53, bcl-2 and c-erbB-2 as predictors of prognosis in breast cancer patients receiving post-mastectomy radiotherapy, which has not been well defined in the Taiwanese population.


METHODS
We recruited 74 consecutive patients with primary operable breast cancer who were treated with mastectomy followed by locoregional radiotherapy and studied the presence of p53, bcl-2 and c-erbB-2 expressions in tumor tissues by immunohistochemical staining. Associations between the protein expressions and clinical outcomes, including local recurrence-free survival (LRFS), metastasis-free survival (MFS) and overall survival (OS), were evaluated.


RESULTS
The median follow-up time was 55 months. Expressions of p53, bcl-2 and c-erbB-2 were observed in 14 (19%), 28 (38%) and 39 (53%) patients, respectively. Both p53 and c-erbB-2 were significant predictors of MFS. The 5-year MFS for p53-negative and p53-positive tumors were 61.2 and 35.7% (P = 0.01) and 5-year MFS for c-erbB-2-negative and c-erbB-2-positive tumors were 71.3 and 42.4% (P = 0.01). Whereas expression of bcl-2 protein is associated with favorable clinicopathological features, it was not related to LRFS, MFS or OS. Multivariate analyses confirmed c-erbB-2 and p53 expressions as predictors of MFS independent of tumor size, histological grading and lymph node involvement.


CONCLUSIONS
Expressions of p53 and c-erbB-2 are independent predictors of MFS in this Taiwanese population. Further research should be conducted on their application in the treatment and follow-up of patients.
Chen
Helen H W
HH
Department of Radiation Oncology, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan.
Su
Wu-Chou
WC
Guo
How-Ran
HR
Chang
Tsai-Wang
TW
Lee
Wen-Ying
WY
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008408:Mastectomy; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D018714:Radiotherapy, Adjuvant; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*; D016896:Treatment Outcome; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
D019253:Proto-Oncogene Proteins c-bcl-2; D018719:Erb-b2 Receptor Tyrosine Kinases; D016159:Tumor Suppressor Protein p53