Controversies in oncology: are genomic tests quantifying homologous recombination repair deficiency (HRD) useful for treatment decision making?

Mechanisms that protect DNA are crucial to preserve the genome integrity from injuries produced by environmental agents or those spontaneously generated during DNA metabolism.1 DNA single-strand breaks (SSBs) are repaired by mismatch repair (MMR), base excision repair (BER) and nucleotide excision repair (NER).1 Non-homologous end joining (NHEJ) or homologous recombination repair (HRR) processes double-strand breaks (DSBs).1 While NHEJ solves DSBs in a potentially inaccurate way, HRR is an error-free pathway that restores the genomic sequence of the broken DNA ends by using the sister chromatid as template for repair.