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HR-positive, HER2-negative breast cancer, stage I-II

HR-positive / HER2-negative breast cancer →

Surgery first, a genomic test to decide whether chemotherapy adds anything, a few weeks of radiotherapy, then five to ten years of endocrine tablets, with a CDK4/6 inhibitor for two or three years if the risk is high.

061 yr182 yr303 yr42Months from diagnosis · solid bar = shortest typical duration, hatched = up to the longest · arrow = continues for yearsPhaseDiagnosisDiagnosis and tests · 2-4 wkSurgerySurgery and recovery · 1-2 wkGenomic assay decisionDiagnosis and tests · 2-3 wkChemotherapy (high genomic risk only)After surgery · 12-18 wkRadiotherapyRadiotherapy · 1-5 wkEndocrine therapySystemic therapy · yearsCDK4/6 inhibitor (high-risk node-posi…After surgery · 104-156 wk · alongsideSurveillanceSurveillance · yearsDoes the genomic score and stage justify chemotherapy?decision 1Is the recurrence risk high enough for a CDK4/6 inhibitor?decision 2Diagnosis and testsSurgery and recoveryAfter surgeryRadiotherapySystemic therapySurveillance
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Typical sequence for stage I-II (early) disease; durations are protocol values (cycle counts and lengths, fraction schedules, guideline follow-up intervals), not averages of real patients. Your team's plan will differ in detail.

Phase by phase

  1. 1. Diagnosis
    weeks 0-4

    Core biopsy with ER, PR, HER2 and Ki-67; mammography and ultrasound, MRI when needed.

    Source
  2. 2. Surgery
    weeks 2-4

    Breast-conserving surgery or mastectomy with sentinel node biopsy; recovery 2-4 weeks.

    Source
  3. 3. Genomic assay decision
    weeks 3-6

    A 21-gene recurrence score (or similar) on the tumour: in TAILORx, women over 50 with node-negative disease and a score of 11-25 gained nothing from chemotherapy.

    Source
    Decision: Does the genomic score and stage justify chemotherapy?
    • Low or intermediate score: skip chemotherapy, go to radiotherapy and endocrine therapy
    • High score, or young with an intermediate score, or four or more nodes: chemotherapy first
  4. 4. Chemotherapy (high genomic risk only)
    weeks 5-23

    Four to six cycles of a taxane-based or anthracycline-taxane regimen, only when the assay or stage shows a high recurrence risk.

    Source
  5. 5. Radiotherapy
    weeks 17-22

    After breast conservation: 26 Gy in 5 fractions over one week (FAST-Forward) or 40 Gy in 15 fractions over 3 weeks; longer courses with a boost in some settings.

    Source
  6. 6. Endocrine therapy
    from week 18, continues for years

    Tamoxifen or an aromatase inhibitor (with ovarian suppression before menopause) for 5 years, extended to 10 in higher-risk disease.

    Source
    Decision: Is the recurrence risk high enough for a CDK4/6 inhibitor?
    • Node-negative, small tumour: endocrine therapy alone
    • Node-positive or high-risk features: add abemaciclib (2 years) or ribociclib (3 years)
  7. 7. CDK4/6 inhibitor (high-risk node-positive)
    weeks 18-174 (alongside the previous phase)

    Abemaciclib for 2 years (monarchE) or ribociclib for 3 years (NATALEE) alongside endocrine therapy in higher-risk disease.

    Source
  8. 8. Surveillance
    from week 278, continues for years

    Clinic visits every 3-6 months for 3 years then yearly, with annual mammography; bone density monitoring on aromatase inhibitors.

    Source

Sources