Breast cancer (core)
Encounter flow
12/12 authoredCanonical 12-phase frame with authored status for this dossier.
Frame
Determine scope: screening vs symptomatic workup vs confirmed disease; capture menopausal status and family-history axis for downstream genetic testing decisions (NCCN Breast 2026)
Clinical scope identified (screening, diagnostic workup, or confirmed disease) with menopausal axis (NCCN Breast 2026)
Patient inputs (16)
ER + PR + HER2 (IHC ± FISH if 2+) define subtype and therapy axis selection
Drives endocrine-therapy choice (tamoxifen vs AI), ovarian-suppression decision (SOFT/TEXT)
Tyrer-Cuzick risk assessment, BRCA testing criteria (NCCN germline 2024)
Performance status drives treatment eligibility, especially for cytotoxic/intensive regimens
BSA for chemotherapy dosing (Mosteller preferred)
BSA computation
Screening eligibility (USPSTF 2024), menopausal status assumptions, dose adjustment, comorbidity burden
Diagnostic mammography + targeted breast US for BI-RADS lesions; baseline staging
Image-guided core biopsy for BI-RADS 4-5; provides histology + receptor status
Baseline before chemotherapy; cytopenias affect dose intensity (NCCN Breast 2026)
Hepatic function for chemo + endocrine therapy dosing + irAE monitoring
Renal function for carboplatin AUC, contrast staging, anti-HER2 dosing
Germline panel per NCCN criteria; drives olaparib eligibility (OlympiA) + risk-reducing surgery counseling
Metastatic HR+/HER2- progressed disease — PIK3CA (alpelisib) and ESR1 (elacestrant) genotyping
Baseline LVEF before anthracycline/trastuzumab; on-treatment surveillance q3 mo on anti-HER2
21-gene recurrence score (Oncotype) drives adjuvant chemo decision in HR+/HER2- (TAILORx)
* = hard-required. Engine cannot meaningfully run until these are filled.
Severity triggers (5)
- informationallife_threateningmalignant_spinal_cord_compression_bone_metsBone metastases with new back pain + neurologic deficit (motor weakness, sensory level, bladder/bowel) — MRI within hoursTrigger could not be auto-evaluated — needs clinician judgement.
- informationalsevereinflammatory_breast_cancer_presentationErythema, peau d-orange, rapidly progressive skin change with biopsy showing dermal lymphatic invasion (T4d) — inflammatory breast cancer (IBC)Trigger could not be auto-evaluated — needs clinician judgement.
- informationalseverehypercalcaemia_of_malignancyCorrected Ca >12 mg/dL with metastatic breast cancer — symptomatic (confusion, AKI, arrhythmia)Trigger could not be auto-evaluated — needs clinician judgement.
- informationalseveretrastuzumab_lvef_drop_or_clinical_hfLVEF drop >=10% to <50% on anti-HER2, or symptomatic HFTrigger could not be auto-evaluated — needs clinician judgement.
- informationalseveresevere_irae_on_pembrolizumabGrade >=3 immune-related toxicity on pembrolizumab (pneumonitis, hepatitis, colitis, myocarditis, endocrinopathy with hospitalization, severe skin)Trigger could not be auto-evaluated — needs clinician judgement.
Workflow calculators
Run this disease's risk and dosing calculators inline.
Recommended regimen
HR+/HER2- adjuvant endocrine therapy ladder- tamoxifenfirst lineSERM20 mg • PO • once daily x 5-10 yearstriggers: premenopausal_low_to_intermediate_riskPremenopausal HR+ adjuvant standard; 10-year duration improves OS in higher-risk (ATLAS); also acceptable postmenopausal if AI intolerancerxcui 10324
- anastrozolefirst linearomatase_inhibitor1 mg • PO • once daily x 5 yearstriggers: postmenopausal_or_ovarian_suppressedPostmenopausal HR+ adjuvant first-line; superior to tamoxifen for DFS (ATAC); recommend bone-density surveillancerxcui 84857
- letrozolefirst linearomatase_inhibitor2.5 mg • PO • once daily x 5 yearstriggers: postmenopausal_or_ovarian_suppressed_alternative_aiAlternative postmenopausal AI; equally efficacious to anastrozole (BIG 1-98)rxcui 72965
- exemestanesecond linearomatase_inhibitor25 mg • PO • once dailytriggers: postmenopausal_ai_switch_for_intoleranceSteroidal AI option; switch strategy after 2-3 yr tamoxifen (TEAM)rxcui 258494
- abemaciclibadd onCDK4_6_inhibitor150 mg • PO • BID x 2 yearstriggers: high_risk_node_positive_hr_pos_her2_negmonarchE (Johnston JCO 2020 PMID 32954927) — 2-year adjuvant abemaciclib + ET improves iDFS in node-positive high-risk HR+/HER2- early breast cancerrxcui 1946825
Auto-drafted A&P note
Subjective
- Possible entry pathways: Screen-detected or diagnostic mammographic abnormality BI-RADS 4-5 (NCCN Breast 2026); Palpable breast mass, nipple discharge (bloody/unilateral), or skin change (NCCN Breast 2026); Biopsy-confirmed invasive breast cancer or DCIS (NCCN Breast 2026).
Objective
- No vitals, labs, or imaging entered for this encounter.
Assessment
**Breast cancer (core)** (onc.breast-cancer.core.v1). Phenotype framing: DCIS vs invasive ductal vs invasive lobular vs special histologies (mucinous, tubular, metaplastic, papillary); contralateral disease vs metastasis; rule out lymphoma, sarcoma in unusual presentations (NCCN Breast 2026) Scope: Determine scope: screening vs symptomatic workup vs confirmed disease; capture menopausal status and family-history axis for downstream genetic testing decisions (NCCN Breast 2026) No severity triggers fired against current inputs.
Plan
Regimen axis: **HR+/HER2- adjuvant endocrine therapy ladder**. 1. tamoxifen 20 mg PO once daily x 5-10 years (SERM, first line) — Premenopausal HR+ adjuvant standard; 10-year duration improves OS in higher-risk (ATLAS); also acceptable postmenopausal if AI intolerance 2. anastrozole 1 mg PO once daily x 5 years (aromatase_inhibitor, first line) — Postmenopausal HR+ adjuvant first-line; superior to tamoxifen for DFS (ATAC); recommend bone-density surveillance 3. letrozole 2.5 mg PO once daily x 5 years (aromatase_inhibitor, first line) — Alternative postmenopausal AI; equally efficacious to anastrozole (BIG 1-98) 4. exemestane 25 mg PO once daily (aromatase_inhibitor, second line) — Steroidal AI option; switch strategy after 2-3 yr tamoxifen (TEAM) 5. abemaciclib 150 mg PO BID x 2 years (CDK4_6_inhibitor, add on) — monarchE (Johnston JCO 2020 PMID 32954927) — 2-year adjuvant abemaciclib + ET improves iDFS in node-positive high-risk HR+/HER2- early breast cancer AVOID / contraindication checks: - Tamoxifen_avoid_active_vte_or_endometrial_hyperplasia - Ai_avoid_premenopausal_unless_ovarian_suppression (SOFT/TEXT framework) - Abemaciclib_hold_grade_3_4_diarrhea_or_neutropenia_or_ILD - Bone_density_baseline_q2y_on_AI
Monitoring
Regimen monitoring: - menstrual status and endometrial symptoms on tamoxifen - lipid panel q6 12mo on AI - bone mineral density baseline then q2y on AI - CBC LFT q2 4wk on abemaciclib first 2 months then monthly - CT chest for ILD if abemaciclib pulmonary symptoms Follow-up plan: NCCN survivorship intervals: H&P q3-6 mo x 5 yr then annual; annual mammogram; 5-10 yr endocrine therapy adherence; fertility preservation conversation if premenopausal at diagnosis; sexuality + lymphedema + psychosocial support; genetic counseling for cascade testing if BRCA+ (NCCN Breast 2026) - Close-out criterion: Survivorship plan documented with next scan + endocrine duration + cascade-testing plan (NCCN Breast 2026) Monitoring phase: Echo q3 mo on anti-HER2 (cardiotoxicity); CBC + LFT before each cycle; q2-4 wk TSH + LFT + glucose on pembrolizumab (irAE); bone density on AI (q2 yr); endocrine-therapy adherence checks; symptom monitoring for recurrence (NCCN Breast 2026)
Disposition
Disposition phase: Outpatient infusion centre for systemic therapy; inpatient for surgical resection (lumpectomy/mastectomy with SLNB/ALND), neutropenic fever, severe irAE, oncologic emergency; transition to palliative team when goals shift (NCCN Breast 2026) - Advance when: Care setting and treatment timeline established (NCCN Breast 2026)
Earlier-Return Triggers
Return-precaution thresholds (watch for): - [LIFE_THREATENING] Bone metastases with new back pain + neurologic deficit (motor weakness, sensory level, bladder/bowel) — MRI within hours - [SEVERE] Erythema, peau d-orange, rapidly progressive skin change with biopsy showing dermal lymphatic invasion (T4d) — inflammatory breast cancer (IBC) - [SEVERE] Corrected Ca >12 mg/dL with metastatic breast cancer — symptomatic (confusion, AKI, arrhythmia)
Citations
- NCCN Breast 2026 + St Gallen 2025 + USPSTF 2024 screening + ASCO 2022 metastatic + NCCN germline 2024 [PMID:32954927](https://pubmed.ncbi.nlm.nih.gov/32954927/) - Cited evidence (PMID 32101663) [PMID:32101663](https://pubmed.ncbi.nlm.nih.gov/32101663/) - Cited evidence (PMID 34081848) [PMID:34081848](https://pubmed.ncbi.nlm.nih.gov/34081848/) - Cited evidence (PMID 29860917) [PMID:29860917](https://pubmed.ncbi.nlm.nih.gov/29860917/) - Cited evidence (PMID 30516102) [PMID:30516102](https://pubmed.ncbi.nlm.nih.gov/30516102/) Last reconciled with current guidelines: 2026-05-26.
- NCCN Breast 2026 + St Gallen 2025 + USPSTF 2024 screening + ASCO 2022 metastatic + NCCN germline 2024 — PMID:32954927
- Cited evidence (PMID 32101663) — PMID:32101663
- Cited evidence (PMID 34081848) — PMID:34081848
- Cited evidence (PMID 29860917) — PMID:29860917
- Cited evidence (PMID 30516102) — PMID:30516102