Chemosensitivity across menstrual cycle phases in premenopausal triple-negative breast cancer

Chemosensitivity During Phases of the Menstrual Cycle in Breast Cancer Patients

Not applicable Interventional The Netherlands Cancer Institute · NCT06273800

This project tests whether a blood sample taken at the start of neoadjuvant chemotherapy can reveal differences in chemosensitivity related to menstrual cycle phase in premenopausal women with stage I–III triple-negative breast cancer.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years to 59 Years
SexFemale
SponsorThe Netherlands Cancer Institute Academic / other
Drugs / interventionschemotherapy, immunotherapy
Locations1 site (Amsterdam, North Holland)
Trial IDNCT06273800 on ClinicalTrials.gov

What this trial studies

This is a prospective, multicenter study enrolling premenopausal women with newly diagnosed stage I–III triple-negative breast cancer who have not yet received systemic therapy. A serum sample is collected on the day neoadjuvant treatment begins and will be used to study biomarkers of chemosensitivity in relation to menstrual cycle phase. Patients using hormonal contraception or with suppressed ovarian function are excluded to preserve natural cycle effects. The goal is to correlate blood-based signals with cycle timing and planned neoadjuvant therapy to inform whether cycle phase influences treatment response.

Who should consider this trial

Good fit: Ideal candidates are premenopausal women under 60 with newly diagnosed stage I–III or locoregional recurrent triple-negative breast cancer who are systemic treatment–naïve, have regular menstrual cycles, and are starting neoadjuvant chemotherapy.

Not a fit: Postmenopausal women, patients already on or recently using hormonal contraception or ovarian suppression, those who have received prior systemic therapy for this cancer, or patients with non–triple-negative or metastatic disease are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, the findings could help tailor the timing of neoadjuvant chemotherapy to a patient’s menstrual cycle to improve response rates or reduce toxicity.

How similar studies have performed: Small translational studies have suggested that menstrual hormones can affect tumor biology and chemosensitivity, but large prospective clinical evidence is limited, so this approach remains relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Women with a new diagnosis of triple negative breast cancer who have not yet started systemic treatment.
* Patients with stage I-III disease, patient with locoregional recurrence who have not been treated with chemotherapy before. ,
* Aged \< 60 years
* Women having a (regular) physiological menstrual cycle
* Patients who are assigned to receive neoadjuvant chemotherapy with or without immunotherapy, targeted therapy and endocrine therapy
* Patients must be systemic treatment naïve for current malignancy (e.g. no chemotherapy, hormonal therapy or targeted therapy)
* Signed written informed consent

Exclusion Criteria:

* current use of hormonal contraception or in the six weeks prior to start of neoadjuvant systemic treatment for breast cancer, such as:
* Oral contraception (OAC)
* Hormonal intra-uterine device (IUD, Mirena)
* No ovarian function suppression to preserve fertility
* Other forms of hormonal contraception, including but not limited to: nuva-ring, Implanon, prikpil
* Currently pregnant and / or breast feeding. In case of use of hormonal contraception or breast feeding in de last year: patients should have had at least 2 menstrual cycles since stopping hormonal contraception.

  \- active other malignancy
* IVF-trajectory for egg cell preservation prior to start of neoadjuvant systemic treatment

Where this trial is running

Amsterdam, North Holland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Breast CancerTriple negative tumorStage I - III diseaseStarting neo adjuvant treatmentRegular physiological menstrual cycle
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.