HER2 Support Group Forums - View Single Post - Researchers Ponder Shorter Course of AI therapy

Hopeful · 08-26-2009, 12:10 PM

The discussion I posted is in reference to the article,

"Endocrine Therapy plus Zoledronic Acid in Premenopausal Breast Cancer" from the February 12, 2009 NEJM. Dr. Gnant was one of the authors.

The full text of the NEJM article appears here: http://content.nejm.org/cgi/content/full/360/7/679

Dr. Gnant's comments above go to this portion of the article:

"The results of our study showed that in premenopausal women with early breast cancer, treatment with anastrozole and treatment with tamoxifen were associated with similar rates of disease-free survival. The addition of zoledronic acid to adjuvant endocrine therapy increased the rate of disease-free survival, as compared with endocrine therapy alone. At a median follow-up of 47.8 months, 821 of 904 patients who received endocrine therapy alone (90.8%) were free of disease, and 878 of 904 patients (97.1%) were alive; in the cohort of patients who received zoledronic acid, 845 of 899 patients (94.0%) were disease-free and 883 of 899 (98.2%) were alive. The absolute difference in disease-free survival was 3.2 percentage points, favoring the patients who received zoledronic acid as compared with the patients who did not receive zoledronic acid (P=0.01). This difference is similar to the 5-year absolute difference in disease-free survival observed in trials comparing tamoxifen with aromatase inhibitors in postmenopausal women with early breast cancer.5,28 These outcomes add to the growing body of data showing that subgroups of patients with low-risk or intermediate-risk, endocrine-responsive early breast cancer can be spared the adverse events of cytotoxic therapy after locoregional treatment.29 In our study, treatment with goserelin was given for 3 years, on the basis of the outcomes in a previous trial (the Austrian Breast and Colorectal Cancer Study Group trial 5).10
Although the duration of endocrine therapy in premenopausal patients varies internationally (i.e., from 2 to 5 years), the data from ABCSG-12 indicate that ovarian suppression with endocrine therapy for 3 years can produce excellent outcomes in a population with low-to-intermediate risk. The estimated number needed to treat to prevent disease progression in 1 patient in the intention-to-treat cohort was 31 in the group of patients who received zoledronic acid at a median follow-up of 47.8 months. In contrast, in a meta-analysis of taxane therapy in postmenopausal women with early breast cancer, the numbers needed to treat to prevent disease progression in 1 patient were 28 with the use of paclitaxel (with a median follow-up of 60 to 69 months) and 31 with the use of docetaxel (with a median follow-up of 43 to 60 months).30 Thus, the addition of zoledronic acid to endocrine therapy is consistent with the number needed to treat for cancer therapies that in the past have caused a shift in treatment standards. "

In the authors' response to letters to the editor concerning the article, it was reiterated:

"according to St. Gallen and National Comprehensive Cancer Network guidelines, goserelin plus tamoxifen is an accepted treatment for premenopausal patients with endocrine-responsive breast cancer, and luteinizing hormone–releasing hormone agonists alone are associated with a strong trend toward reduced rates of recurrence and death.1 In the ABCSG-12 study, the selection of 3 years of endocrine therapy was based on the findings of the ABCSG-5 trial (ClinicalTrials.gov number, NCT00309478 [ClinicalTrials.gov] ) (which examined 3 years of goserelin, then 5 years of tamoxifen).2 However, 5 years of continuous endocrine therapy may not be necessary in this low-risk population, since it would be difficult to improve the 98.2% 4-year overall survival achieved in the group receiving zoledronic acid in the ABCSG-12 trial. We agree that long-term follow-up of SOFT and Triptorelin with Exemestane on Tamoxifen (TEXT) (NCT00066703 [ClinicalTrials.gov] ) may provide more definitive guidance on the use of aromatase inhibitors in premenopausal patients with breast cancer. "

Hopeful

08-26-2009, 12:10 PM	#8
Hopeful Senior Member Join Date: Aug 2006 Posts: 3,380	Re: Researchers Ponder Shorter Course of AI therapy The discussion I posted is in reference to the article, "Endocrine Therapy plus Zoledronic Acid in Premenopausal Breast Cancer" from the February 12, 2009 NEJM. Dr. Gnant was one of the authors. The full text of the NEJM article appears here: http://content.nejm.org/cgi/content/full/360/7/679 Dr. Gnant's comments above go to this portion of the article: "The results of our study showed that in premenopausal women with early breast cancer, treatment with anastrozole and treatment with tamoxifen were associated with similar rates of disease-free survival. The addition of zoledronic acid to adjuvant endocrine therapy increased the rate of disease-free survival, as compared with endocrine therapy alone. At a median follow-up of 47.8 months, 821 of 904 patients who received endocrine therapy alone (90.8%) were free of disease, and 878 of 904 patients (97.1%) were alive; in the cohort of patients who received zoledronic acid, 845 of 899 patients (94.0%) were disease-free and 883 of 899 (98.2%) were alive. The absolute difference in disease-free survival was 3.2 percentage points, favoring the patients who received zoledronic acid as compared with the patients who did not receive zoledronic acid (P=0.01). This difference is similar to the 5-year absolute difference in disease-free survival observed in trials comparing tamoxifen with aromatase inhibitors in postmenopausal women with early breast cancer.5,28 These outcomes add to the growing body of data showing that subgroups of patients with low-risk or intermediate-risk, endocrine-responsive early breast cancer can be spared the adverse events of cytotoxic therapy after locoregional treatment.29 In our study, treatment with goserelin was given for 3 years, on the basis of the outcomes in a previous trial (the Austrian Breast and Colorectal Cancer Study Group trial 5).10 Although the duration of endocrine therapy in premenopausal patients varies internationally (i.e., from 2 to 5 years), the data from ABCSG-12 indicate that ovarian suppression with endocrine therapy for 3 years can produce excellent outcomes in a population with low-to-intermediate risk. The estimated number needed to treat to prevent disease progression in 1 patient in the intention-to-treat cohort was 31 in the group of patients who received zoledronic acid at a median follow-up of 47.8 months. In contrast, in a meta-analysis of taxane therapy in postmenopausal women with early breast cancer, the numbers needed to treat to prevent disease progression in 1 patient were 28 with the use of paclitaxel (with a median follow-up of 60 to 69 months) and 31 with the use of docetaxel (with a median follow-up of 43 to 60 months).30 Thus, the addition of zoledronic acid to endocrine therapy is consistent with the number needed to treat for cancer therapies that in the past have caused a shift in treatment standards. " In the authors' response to letters to the editor concerning the article, it was reiterated: "according to St. Gallen and National Comprehensive Cancer Network guidelines, goserelin plus tamoxifen is an accepted treatment for premenopausal patients with endocrine-responsive breast cancer, and luteinizing hormone–releasing hormone agonists alone are associated with a strong trend toward reduced rates of recurrence and death.1 In the ABCSG-12 study, the selection of 3 years of endocrine therapy was based on the findings of the ABCSG-5 trial (ClinicalTrials.gov number, NCT00309478 [ClinicalTrials.gov] ) (which examined 3 years of goserelin, then 5 years of tamoxifen).2 However, 5 years of continuous endocrine therapy may not be necessary in this low-risk population, since it would be difficult to improve the 98.2% 4-year overall survival achieved in the group receiving zoledronic acid in the ABCSG-12 trial. We agree that long-term follow-up of SOFT and Triptorelin with Exemestane on Tamoxifen (TEXT) (NCT00066703 [ClinicalTrials.gov] ) may provide more definitive guidance on the use of aromatase inhibitors in premenopausal patients with breast cancer. " Hopeful Last edited by Hopeful; 08-26-2009 at 12:12 PM..