Clinical trial · Observational
Impact of Endocrine Therapy, Menstrual Cycle, PAM50, Ki67 on Treatment Decisions in HR+ and HER2- Breast Cancer
Impact of Preoperative Endocrine Therapy, Menstrual Cycle, PAM50 Assessment and Ki67 Dynamics on Adjuvant Treatment Decisions in Hormone Receptor-positive and HER2-negative Patients With Early Breast Cancer
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
PEAK is a prospective, multicenter, non-interventional investigator-initiated trial (IIT) that aims to investigate the influence of the menstrual cycle phase on Ki67 in patients who either receive Tamoxifen, Aromatase inhibitors ± gonadotropin-releasing hormone (GnRH)-Analogues or nothing or no preoperative endocrine treatment as part of the clinical routine. The investigators moreover address the question whether PAM50 assessment in addition to Ki67 dynamics still impacts treatment recommendations.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Hormone Receptor Positive HER-2 Negative Breast Cancer | — | UNRESOLVED | — |
Interventions
Interventions (0)
Data not yet available
Design
Arms and outcomes
Arms (3)
- label
- Group A: Tamoxifen
- description
- Patients with early HR+/HER2- Breast cancer receiving Tamoxifen
- label
- Group B: Aromatase Inhibitor (+GnRH if premenopausal)
- description
- Patients with early HR+/HER2- Breast cancer receiving Aromatase Inhibitor (+GnRH if premenopausal)
- label
- Group C: Control group
- description
- no preoperative endocrine treatment
Primary outcomes (1)
- measure
- Influence of the menstrual cycle on initial Ki67 in premenopausal women
- timeFrame
- duration of therapy and follow-up data (10 years)
- description
- The number of Ki67 positive cell nuclei will be estimated for the entire core biopsy in a semiquantitative evaluation in steps of 10% by a board certified pathologist as part of the clinical routine workup. Ki67 assessment will be conducted on breast core biopsy (I) and surgical specimen (II).
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: * women ≥ 18 years of age * histologically proven unilateral primary non-metastatic invasive breast cancer * Estrogen receptor (ER)-/ or Progesterone receptor (PR)- positive and HER2-negative * Ki67 from core biopsy is available * no lymph-node involvement by clinical evaluation and ultrasound (cN0) * not amendable to neoadjuvant chemotherapy * surgery or planned surgery at the Department for Women's Health, Tuebingen or Freiburg * planned preoperative endocrine treatment with Tamoxifen, Aromatase inhibitors, Goserelin or nothing for 2 - 4 weeks * written informed consent Exclusion Criteria: * ER-negative and PR-negative * HER2-positive * bilateral breast cancer * preexisting cancer disease within the last 10 years * preexisting invasive ipsi- or contralateral breast cancer (non-invasive ipsi- or contralateral breast cancer is not regarded as an exclusion criteria) * any systemic breast cancer therapy before inclusion into the trial * indication for neoadjuvant chemotherapy * any systemic therapy except Tamoxifen, Aromatase inhibitors, Goserelin before surgery * locally advanced, inoperable or metastatic breast cancer * pregnant or lactating patients * inadequate general condition (not fit for chemotherapy) * hormonal contraception within 6 months before inclusion
References
Publications (0)
Data not yet available