Olaparib in Metastatic Breast Cancer: BRCA Diagnostics from the Germ Line as Indication Criterion
According to the scientific literature, before therapy with Olaparib (Lynparza®/PARP inhibitor) in patients with advanced HER2-negative breast carcinoma (TNBC and HR+/HER2-), proof of a BRCA mutation of the germ line is required
It states: "Lynparza is indicated as monotherapy for the treatment of adult patients with germline BRCA1/2-mutations, who have HER2-negative locally advanced or metastatic breast cancer". This means that, unlike the approval of Olaparib for ovarian cancer, only the detection of a BRCA mutation from blood is the valid indication criterion for treatment. Detection of a BRCA mutation in tumour tissue is not an indication criterion.
Nevertheless, parallel analysis of the tumour tissue is indicated in order to detect further biomarkers relevant for therapy, such as PIK3A. Ideally, both the human genetic and the pathological results are available at the same time, so that a quick therapy decision can be made in the interest of the patients concerned.
The germ line analysis of BRCA1 and BRCA2, among others, requires a considerably higher technical analysis quality than the analysis of tumor tissue according to the guidelines (S1 guideline for NGS diagnostics), thus a higher diagnosis rate can be assumed.
The following gene panel(s) can be requested for genetic testing of the BRCA mutation:
Gene Panel ID 109.00 - Genes included: BRCA1, BRCA2
Gene Panel ID 360.00 - Genes included: BRCA1, BRCA2, CHEK2, PALB2, RAD51C
For questions about genetic testing for Olaparib, and its suitability for your patients, send an email to firstname.lastname@example.org.