Doctor's Guide to Medical & Other News


To print: Select File and then Print from your browser's menu
---------------------------------------------------------------------------------------
Title: ASTRO: HER-2/neu Overexpression Does Not Predict Risk of Local Recurrence After Mastectomy, Doxorubicin and Radiation
URL: http://www.pslgroup.com/dg/23D78E.htm
Doctor's Guide
October 31, 2003


By Charlene Laino

SALT LAKE CITY, UT -- October 31, 2003 -- Contrary to what has been suggested, breast cancer patients whose tumors overexpress HER-2/neu are not at an increased risk for local recurrence after mastectomy, doxorubicin and radiation, a new study suggests.

Thomas Buchholz, MD, a radiation oncologist at the University of Texas MD Anderson Cancer Center in Houston, Texas, United States, presented the findings here on October 21st at the 45th Annual Meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO).

"HER-2/neu is overexpressed in 20% to 30% of breast cancers," he said, and a small case-control study suggested that after breast cancer therapy, overexpression of HER-2/neu is more common in recurrent tumors.

The researchers, therefore, decided to look at a larger group of women to confirm whether patients whose tumors overexpressed HER-2/neu were more likely to develop local-regional recurrence after postmastectomy radiation than patients whose tumors did not overexpress HER-2/neu, he said.

The researchers studied 108 patients treated in four prospective clinical trials with neoadjuvant chemotherapy, mastectomy and radiation whose tumors had been tested for HER-2/neu expression.

All the women received a neoadjuvant combination chemotherapy regimen that included doxorubicin, with 53% also receiving a taxane, he said. Radiation treatment at a median dose of 50 Gy was delivered to the chest wall and draining lymphatics, followed by a median boost of 10 Gy to the chest wall.

Thirty-two patients had tumors that overexpressed HER-2/neu, as determined by immunohistochemistry or fluorescent in situ hybridization, Dr. Buchholz reported. The remaining patients had tumors in which the HER-2/neu test was considered normal.

Patients whose tumors were HER-2/neu positive were more likely to have estrogen receptor-negative disease: 72% versus 49% for those who tumors were HER-2/neu normal (p=0.03), the study showed. Also, patients with HER-2/neu positive tumors had a higher number of median positive lymph nodes after chemotherapy: six, compared with three for women whose tumors were HER-2/neu normal (p=0.002).

Nevertheless, the actuarial overall local regional recurrence rate was roughly equivalent for the patients with HER-2/neu overexpression, compared with those whose tumors were normal for HER-2/neu, Dr. Buchholz reported.

At 10 years, for example, the local recurrence rate was 17.5% in women with HER-2/neu positive tumors versus 18.9% for women whose tumors were HER-2/neu normal (p=0.76). Multivariate analysis showed that the hazard ratio for HER-2/neu positivity was 0.89, he added.

"Local regional recurrence of HER-2/neu positive tumors is not higher than HER-2/neu negative tumors after neoadjuvant doxorubicin-based chemotherapy, mastectomy and radiation," Dr. Buchholz concluded.


[Study title: HER-2/neu Overexpression Does Not Increase the Risk of Local-Regional Recurrence for Patients Treated with Neoadjuvant Doxorubicin-Based Chemotherapy, Mastectomy, and Radiation. Abstract 127]

---------------------------------------------------------------------------------------------
Copyright © 1999 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content.
---------------------------------------------------------------------------------------------
This news story was printed from *Doctor's Guide to the Internet*
located at http://www.docguide.com
---------------------------------------------------------------------------------------

Return to News Story Page

This site is maintained by webmaster@pslgroup.com
Please contact us with any comments, problems or bugs.
All contents Copyright (c) 1998 P\S\L Consulting Group Inc.
All rights reserved.