2.3.4. Case 13179: Right Prostate Tumour Core Biopsy

This *TMPRSS2-ERG* positive tumour is characterised by a high PGA at 26%, pathogenic somatic SNV in *TP53* (rs28934575, c.733G > A; p.Gly245Ser), as well as copy number loss of *PTEN*. Additional losses in *MAP3K1, PIK3R1* and *TP53* were observed, along with somatic alterations in the MAPK and PI3K pathways (Figure 5).

Co-loss of *TP53* and *PTEN* is associated with more aggressive disease, which is consistent with this patient's clinical course. Knowledge of these molecular features may have triggered more aggressive treatment upfront. Within current treatment paradigms, this may have included radiotherapy with ADT and docetaxel [5,71]. Additionally, the number of alterations in multiple targetable pathways, particularly PI3K (PI3K/AKT inhibitors) and MAPK/ERK (BRAF/MEK inhibitors), highlights the need to contextualise genomic events rather than viewing them in isolation. It is likely that this patient's treatment regimen would need to involve a tailored combination strategy if a targeted, precision-medicine approach was to be considered.
