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Egyptian Board Clinical Oncology study materials
Egyptian Board Clinical Oncology study resources

Egyptian Board Clinical Oncology: Breast Cancer

Egyptian Board Clinical Oncology · Work through your exam, one topic at a time.

All guide sections

Breast Cancer

What this domain tests

Breast cancer items test subtype-driven decision-making: when genomic assays change adjuvant chemotherapy, how nodal surgery has de-escalated, which patients need post-mastectomy radiotherapy, and how the HER2, triple-negative and hormone-receptor pathways dictate successive lines in metastatic disease.

Core rules

  • Subtypes by receptor: HR+/HER2−, HER2+, triple-negative. Staging in AJCC 8th edition uses the anatomic stage plus a prognostic stage incorporating grade, ER/PR, HER2 and genomic score.
  • Early breast conservation requires whole-breast radiotherapy; omission is reasonable only in selected older patients with low-risk, ER-positive tumors on endocrine therapy.
  • Sentinel node biopsy has replaced axillary dissection in clinically node-negative disease. ACOSOG Z0011 applies only to 1–2 positive sentinel nodes treated with breast conservation and whole-breast irradiation.
  • Genomic assays: Oncotype DX (TAILORx, RxPONDER), MammaPrint (MINDACT). In postmenopausal women with 1–3 positive nodes and a low recurrence score, RxPONDER showed no chemotherapy benefit; premenopausal women did benefit.
  • HER2 disease: trastuzumab for ≥1 cm or node-positive; pertuzumab added in high-risk node-positive disease; paclitaxel–trastuzumab for small node-negative tumors (APT). Residual disease after neoadjuvant therapy gets T-DM1 (KATHERINE); triple-negative residual disease gets capecitabine (CREATE-X).
  • Metastatic sequencing: CDK4/6 inhibitor plus endocrine therapy first line for HR+; alpelisib for PIK3CA-mutant; olaparib or talazoparib for germline BRCA; sacituzumab govitecan for triple-negative; trastuzumab deruxtecan for HER2-low and later-line HER2+.

Worked example

A 60-year-old postmenopausal woman has a 2.5 cm, ER-positive, HER2-negative tumor with one positive sentinel node. Oncotype recurrence score is 16. Under RxPONDER, a postmenopausal woman with 1–3 nodes and recurrence score ≤25 derives no chemotherapy benefit; she receives whole-breast radiotherapy plus an aromatase inhibitor. The same tumor in a premenopausal woman would justify chemotherapy plus ovarian suppression.

Traps

  • Applying Z0011 to mastectomy patients, to three or more positive nodes, or to partial-breast irradiation.
  • Treating HER2-low as a separate subtype requiring first-line trastuzumab deruxtecan.
  • Using Ki-67 alone to justify chemotherapy.
  • Forgetting bone-modifying agents and cardiac surveillance in long-term endocrine and trastuzumab therapy.