Table 1.

Endocrine treatment of early breast cancer

Menopausal status at time of diagnosis	Type of endocrine therapy	Reasons for therapy selection	Extended therapy: considerations	Type of extended therapy
Postmenopausal	AI (5 years)	High risk of early relapse History of thromboembolic disease Depression	No significant OS benefit Shared decision making if N2, N3, and AI well tolerated	AI (2 years)
	AI (2–3 years) -> Tam (2–3 years)	Higher risk Relevant cardiovascular disease	High risk, e.g., N2, N3, and treatment well tolerated	AI (2–5 years) or Tam (2–5 years)
	Tam (2–3 years) -> AI (2–3 years)	Intermediate risk Osteopenia/osteoporosis Relevant cardiovascular disease	High risk, e.g., N2, N3, and treatment well tolerated	AI (2–5 years) or Tam (2–5 years)
	Tam (5 years)	Low risk	Higher risk	AI (2–5 years) or Tam (5 years)
Peri- and Premenopausal	Tam (5 years)	Low and intermediate risk	Intermediate risk	Tam (5 years) or AI (2–5 years) if postmenopausala
	Tam (5 years) + OFS (2–5 years)	<35 years or becoming premenopausal during the 2 years following chemotherapy	High risk	Tam (5 years) or AI (5 years) if postmenopausala
	OFS (up to 5 years)	Tam contraindicated and low risk	-	-
	AI + OFS (5 years)	Tam contraindicated and intermediate or high risk	-	-

AI, aromatase inhibitor; Tam, tamoxifen; OFS, ovarian function suppression; COF, chemotherapy-induced ovarian failure.

^aTesting of E2/FSH after COF repeatedly before and during treatment. Treat osteopenia and osteoporosis according to guidelines; consider bisphosphonate oral or intravenous in osteoprotective dosage for patients (1) more than 5 years after menopause or (2) during therapy with AI or OFS.