Cancer Cell: Mapping the molecules of ductal carcinoma in situ (DCIS).

A team of researchers mapping ductal carcinoma in situ (DCIS) has made significant progress in distinguishing whether early precancerous breasts will progress
to invasive cancer or remain stable.

By analyzing patient samples from patients who had surgically removed the DCIS region, the team found 812 genes
associated with cancer progression.
Using this gene classifier, they were able to predict the risk of
cancer cells coming back or progressing.

The study, published this week in the journal Cancer Cell, was published by E.
Bu of the Duke Cancer Institute.
Led by Shelley Hwang, MD, and Rob West, MD, Stanford University Medical Center
.
Their work is part of
the Human Tumor Atlas network under the National Cancer Institute-funded Moonshot Initiative.

Professor Hwang said: "There has been a long
debate about whether DCIS is a cancer or a high-risk disease.
"In the absence of a way to be sure, we currently treat all patients
with surgery, radiotherapy, or both.

"More than 50,000 women are diagnosed with DCIS each year, and about a third of them undergo mastectomy, so we are increasingly concerned that we may be overtreating
many women.
" "We need to better understand the biology of DCIS, which is the purpose of
our study.
"

Hwang, West and colleagues analyzed 774 DCIS samples from 542 patients with a median time after treatment of 7.
4 years
.
They identified 812 genes
associated with relapse within 5 years of treatment.

Gene classifiers are able to predict cancer recurrence and aggressive progression, which appears to rely on interactions between aggressive DCIS cells and unique features
of the tumor environment.

Most DCIS cancers analyzed in the study were determined to be at low risk of cancer progression or recurrence, a factor that underscores the need for an accurate predictive model that can be used to guide treatment
at clinical visits, Hwang said.

"We've made great strides in our understanding of DCIS, and this work gives us a real path to personalize care
by scaling treatments based on the risk of cancer progression.
" "The real goal is to reduce treatment-related harm without compromising outcomes, and we're excited to get closer to that goal
for DCIS patients.
"

In addition to Hwang and West, the study's authors included co-principal investigator Carlo Maley, Ph.
D.
, from the Arizona State College of Life Sciences, and Graham Colditz, Ph.
D.
, from the Center for Pre-Breast Cancer Atlas at Washington University in St.
Louis, and collaborators
from 12 other institutions in the Translational Breast Cancer Alliance.