What are the findings and recommendations of the STOPHER (Selective Targets Overcoming Postmenopausal Hormone-sensitive breast cancer Resistance) trial for the treatment of hormone receptor-positive breast cancer?

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The STOPHER Trial Does Not Exist in Breast Cancer Literature

There is no published clinical trial called "STOPHER" (Selective Targets Overcoming Postmenopausal Hormone-sensitive breast cancer Resistance) in the breast cancer literature. The provided evidence contains no references to any trial by this name, and this appears to be either a misremembered trial name or a non-existent study.

Major Adjuvant Endocrine Therapy Trials You May Be Thinking Of

The landmark trials that have shaped adjuvant endocrine therapy for hormone receptor-positive breast cancer include:

Primary Adjuvant Aromatase Inhibitor Trials

  • ATAC Trial (Arimidex, Tamoxifen, Alone or in Combination): Compared anastrozole versus tamoxifen versus combination therapy for 5 years in 9,366 postmenopausal women, showing superior disease-free survival with anastrozole (HR 0.87,95% CI 0.78-0.97, P=0.01) 1, 2
  • BIG 1-98 Trial: Demonstrated letrozole superiority over tamoxifen for disease-free survival (HR 0.81,95% CI 0.70-0.93, P=0.003) 2

Sequential Therapy Trials

  • IES Trial (Intergroup Exemestane Study): Compared switching to exemestane after 2-3 years of tamoxifen versus continuing tamoxifen, showing improved disease-free survival with the switch (HR 0.68,95% CI 0.56-0.82, P=0.00005) 1
  • TEAM Trial (Tamoxifen Exemestane Adjuvant Multinational): Compared exemestane monotherapy versus sequential tamoxifen followed by exemestane, finding no difference in disease-free survival at 5 years (HR 0.97,95% CI 0.88-1.08, P=0.60), confirming both strategies as reasonable options 3, 4
  • ITA Trial (Italian Tamoxifen Anastrozole): Evaluated switching to anastrozole after 2-3 years of tamoxifen 1
  • ABCSG 8/ARNO 95 Trials: Austrian and German trials examining sequential therapy strategies 1

Extended Therapy Trials

  • MA.17 Trial: Enrolled 5,187 postmenopausal women who completed 4.5-6 years of tamoxifen and randomized them to letrozole versus placebo for 5 additional years, showing superior disease-free survival (94.4% vs 89.8%, HR 0.58, P<0.001) and improved overall survival specifically in node-positive patients (HR 0.61,95% CI 0.38-0.98, P=0.04) 1, 2

Premenopausal Trials

  • TEXT/SOFT Trials (Tamoxifen and Exemestane Trial/Suppression of Ovarian Function Trial): Demonstrated that premenopausal women with high recurrence risk may experience 10-15% absolute improvement in 8-year freedom from distant recurrence with exemestane plus ovarian function suppression versus tamoxifen alone 5

Current Guideline Recommendations Based on These Trials

The NCCN explicitly recommends aromatase inhibitors preferentially over tamoxifen alone in postmenopausal women with hormone receptor-positive breast cancer 2. Three acceptable strategies exist:

  • Initial adjuvant therapy: Aromatase inhibitor for 5 years 2
  • Sequential therapy: 2-3 years of tamoxifen followed by aromatase inhibitor to complete 5 years total 1, 2
  • Extended therapy: Aromatase inhibitor after completing 4.5-6 years of tamoxifen 1, 2

Common Pitfall to Avoid

Do not confuse trial acronyms—the major trials are ATAC, BIG 1-98, IES, TEAM, MA.17, TEXT, and SOFT. No "STOPHER" trial exists in the published literature 1, 2.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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