Adjuvante Endokrine Therapie des Mammakarzinoms – Standards und neue Daten

Das Hormonrezeptor-positive Mammakarzinom macht den größten Anteil aller frühen Mammkarzinome aus. Bei prämenopausalen Patientinnen ist Tamoxifen Therapie der Wahl, Aromataseinhibitoren sind aufgrund der ovariellen Aktivität kontraindiziert. In der postmenopausalen Situation werden neben Tamoxifen auch Aromataseinhibitoren eingesetzt. Diese können als initiale Therapie für 5 Jahre, als Sequenztherapie nach 2–3 Jahren Tamoxifen oder als erweiterte Endokrine Therapie nach 5 Jahren Tamoxifen eingesetzt werden. Aktuell ist allerdings die Frage nach der optimalen Therapie der prämenopausalen Patientin im Fokus des Interesses. Welche Patientin sollte eine 10-jährige Tamoxifentherapie und welche eine Therapie mit einem Aromataseinhibitor in Kombination mit einem Gonadotropin Releasing Hormon(GnRH)-Analogon erhalten? Neue Daten, die in den vergangenen 2–3 Jahren publiziert wurden, zeigen einen Benefit durch die Kombination eines Aromataseinhibitors mit GnRH-Analogon und durch die Erweiterung einer Tamoxifentherapie auf 10 Jahre. Dieser Artikel soll zum einen die Standards in der endokrinen Therapie beschreiben, zum anderen aber auch die neuen Daten in einen aktuellen Kontext bringen.

Hormone receptor-positive breast cancers represent the vast majority of early breast cancers. In premenopausal patients tamoxifen is the treatment of choice as aromatase inhibitors are contraindicated due to the endocrine activity of premenopausal patients. In postmenopausal patients aromatase inhibitors are included in the endocrine treatment. Aromatase inhibitors can be used as an initial treatment for 5 years, as sequential treatment after 2–3 years of tamoxifen or as an extended endocrine treatment after 5 years of tamoxifen. However, the optimal treatment of premenopausal patients is currently in the focus of interest. Which patient should undergo a 10-year treatment with tamoxifen and which patient should be treated with a combination of an aromatase inhibitor and a luteinizing hormone-relaesing hormone (LHRH) agonist? New data that had been published in the last 2-3 years presented beneficial results by using a combination of an aromatase inhibitor and a luteinizing hormone-releasing hormone (LHRH) agonist, moreover by utilizing a tamoxifen treatment of 10 years. The aim of this article is to describe the standard of care in endocrine treatment and to put the new data in the right context.

Key words

Breast cancer - endocrine treatment - aromatase inhibitor - tamoxifen - LHRH agonist

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