Among the ninety thousand people who ran Sydney’s City2Surf fun run, Robyn Smith was impossible to miss.

She ran topless - not for shock value, but to make visible something that is usually unseen.

Robyn had a preventative mastectomy after learning she'd inherited the BRCA2 gene variant which increases the risk of breast and ovarian cancers. 

Up to 10 per cent of cancers are linked to inherited gene variants, but Robyn says affected families are largely invisible in public health policy, underfunded in support services, and absent from the mainstream cancer conversation.