PracticeUpdate: Haematology & Oncology

CONFERENCE COVERAGE 22

39th Annual San Antonio Breast Cancer

Symposium 6–10 DECEMBER 2016 • SAN ANTONIO, TEXAS PracticeUpdate ’s Dr Farzanna Haffizulla interviews Drs Timothy Pluard, Benjamin Anderson and Hope Rugo, who share their insights on precision medicine, anxillary nodes after neoadjuvant treatment, and new data on managing HER2+ disease from SABCS 2016. For our full coverage of SABCS 2016, including interviews with experts such as Drs Matthew Goetz and Minetta Liu, go to practiceupdate.com

© MedMeetingImages/Todd Buchanan 2016

Genomic sequencing of treatment-resistant metastatic breast cancer reveals clinically relevant genetic alterations G enomic sequencing of treatment- resistant, oestrogen receptor-positive metastatic breast cancer has revealed

In contrast to published studies of primary, treatment-naive breast tumours, Dr Wagle’s research focuses on metastatic tumour samples from patients with resistant disease. This represents a clinically important population of patients that is largely uncharacterised by comprehensive exome and transcriptome sequencing. Ofir Cohen, PhD, also of Dana-Farber Can- cer Institute, said, “Our research is part of a growing effort by many researchers to start closing the gap by better understanding the genomic underpinning of the metastatic and resistance states.” Drs Wagle and Cohen and colleagues ana- lysed treatment-resistant metastatic breast tumour samples collected from 130 patients treated at their centre. Pretreatment samples

of primary tumours were analysed from 34 of these patients. The investigators performed next-generation sequencing to sequence the entire exome (genes encoding all the proteins in the oncocyte) and transcriptome (all the genetic messages in the cell that direct protein expression) of these breast cancer samples. Dr Cohen said, “We found that the genomic landscape of drug-resistant oestrogen recep- tor-positive metastatic breast cancer differs significantly from that of primary oestrogen receptor-positive breast cancer. Moreover, we were able to identify multiple clinically relevant genomic and molecular alterations in the metastatic breast cancer biopsies, with implications for choice of next therapy, clin- ical trial eligibility, and novel drug targets.” Whole-exome sequencing demonstrated

multiple genomic and molecular alterations not present in the primary tumour samples. This finding carries implications for choice of next therapy, clinical trial eligibility, and novel drug targets. Nikhil Wagle, MD, of the Dana-Farber Cancer Institute, Boston, Massachusetts, ex- plained, “In spite of tremendous advances in the treatment of oestrogen receptor-positive breast cancer using therapies directed against the oestrogen receptor, patients frequently develop resistance to these therapies. These resistant tumours remain the most common cause of breast cancer death, yet mechanisms by which this resistance develops are poorly understood.”

PRACTICEUPDATE HAEMATOLOGY & ONCOLOGY