Small effect of occult metastases on survival in breast cancer

January 01, 0001

Small effect of occult metastases on survival in breast cancer

These US investigators randomly assigned women with breast cancer to sentinel-lymph-node biopsy plus axillary dissection or sentinel-lymph-node biopsy alone. Paraffin-embedded tissue blocks of sentinel lymph nodes obtained from patients with pathologically negative sentinel lymph nodes were centrally evaluated for occult metastases deeper in the blocks. Both routine staining and immunohistochemical staining for cytokeratin were used at two widely spaced additional tissue levels. Treating physicians were unaware of the findings, which were not used for clinical treatment decisions. The initial evaluation at participating sites was designed to detect all macrometastases larger than 2 mm in the greatest dimension.

They found: "Occult metastases were detected in 15.9% of 3887 patients. Log-rank tests indicated a significant difference between patients in whom occult metastases were detected and those in whom no occult metastases were detected with respect to overall survival, disease-free survival, and distant-disease-free interval. The corresponding adjusted hazard ratios for death, any outcome event, and distant disease were 1.40 and 1.30, respectively. Five-year Kaplan-Meier estimates of overall survival among patients in whom occult metastases were detected and those without detectable metastases were 94.6% and 95.8%, respectively."

They found: "Occult metastases were detected in 15.9% of 3887 patients. Log-rank tests indicated a significant difference between patients in whom occult metastases were detected and those in whom no occult metastases were detected with respect to overall survival, disease-free survival, and distant-disease-free interval. The corresponding adjusted hazard ratios for death, any outcome event, and distant disease were 1.40 and 1.30, respectively. Five-year Kaplan-Meier estimates of overall survival among patients in whom occult metastases were detected and those without detectable metastases were 94.6% and 95.8%, respectively."

The benefit of pursuing these occult breast cancer metastases through routine axillary dissection does not appear to provide clinically significant survival benefit.

For the full abstract, click here.

NEJM 364:412-421, 3 February 2011
© 2011 to the Massachusetts Medical Society
Effect of Occult Metastases on Survival in Node-Negative Breast Cancer. Donald L. Weaver, Takamaru Ashikaga, David N. Krag, et al. Correspondence to Dr. Weaver: [email protected]

Category: X. Female Genital System, Breast. Keywords: breast cancer, metastasis, sentinel node, axillary dissection, survival, randomized controlled trial, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 15 February 2011

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