bcl-2 Expression and apoptosis in primary and metastatic breast carcinomas.
OBJECTIVE
To evaluate the role of bcl-2 and apoptotic index in the progression from primary to metastatic breast carcinoma and their influence on prognosis.


METHODS
bcl-2 expression was examined by immunohistochemistry and apoptotic index by in situ end-labelling in 116 surgical breast carcinomas and lymph node metastases from 50 patients.


RESULTS
bcl-2 was observed in 69 cases (59.4%) of primitive carcinomas and 26 cases (65%) of metastatic breast carcinomas and there was agreement of bcl-2 expression between primary and metastatic sites except in 3 cases. bcl-2 expression was significantly associated with several favourable prognostic features, such as small tumour size (p = 0.03) and oestrogen and progesterone-receptor positivity (p < 0.01 and p < 0.001, respectively). A high apoptotic index was significantly associated with a number of poor prognostic factors, including poorly differentiated carcinomas, large tumour size, high Ki67 expression and high mitotic count (p < 0.001 in all cases). The mean apoptotic index was higher in lymph node metastasis than in primary carcinomas (1.19 vs. 0.69, p < 0.01). A low bcl-2 expression and a high apoptotic index were significantly associated with short-relapse free survival rates (p = 0.02 and p < 0.01, respectively), but only apoptotic extent provided independent prognostic information by multivariate analysis.


CONCLUSIONS
The evaluation of bcl-2 expression and extent of apoptosis may provide useful prognostic information on breast cancer patients; however while increased apoptosis is strongly associated with the progression from primary carcinomas to lymph node metastases, bcl-2 does not seem to play a significant role in this process.
Servicio de Anatomía Patológica, Hospital Universitario Virgen de las Nieves, Granada.
E
E
Villar
M
M
Redondo
I
I
Rodrigo
J
J
García
E
E
Avila
A
A
Matilla
D000328:Adult; D000368:Aged; D017209:Apoptosis; D001940:Breast / Q000378:metabolism; D001941:Breast Diseases / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002277:Carcinoma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D053938:DNA Fragmentation; D005260:Female; D015870:Gene Expression; D019254:Genes, bcl-2; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011379:Prognosis