In prep.

This is a CIHR funded project. It is a collaboration with Eileen Rakowitz at the Sunnybrook Hospital in Toronto, Canada.

Eileen is a radiotherapist who had great foresight and energy to build a cohort tumor banking of many DCIS cases in Ontario from 1993 until present.

This cohort is very well annotated with patient, clinical and pathological information regardin the lesion and patient.

Ductal in situ carcinoma (DCIS) is a very common form of breast lesions background.

DCIS is a non-obligate precursor to invasive "life-threatening" breast cancer invasive ductal carcinoma, IDC.

That is, no all DCIS will become invasive if left untreated (or at least not within the natural lifetime of an individual).

In constrast to such indolent DCIS, some such lesions do progress, escaping from the mammary duct, into the surrounding breast tissue and, if left untreated, to other tissues and organs metastases.

A woman with an indolent DCIS might decide in consultation with her health care practioners towards a milder form of therapy involving on breast conserving surgery BCS

If they suspect she has a more agressive DCIS, then treatment might include BCS with radiotherapy.

The problem is that we have no way currently to decide whether a woman with DCIS benefits from the additional radiotherapy.

Therefore current clinical practice is cautious and leans towards the inclusion of radiotherapy.

We are interested in identifying a molecular signature that can predict whether a woman with DCIS would benefit from a regime with only BCS or BCS + raditiotherapy.

To do this, we are profiling Eileen's Ontario cohorts using next generation sequencing and analysis methods from computational biology.

This data and analyses allow us to glimpse how each such lesion evolved, somatic DNA events and changes in the regulation and expression of specific pathways.

From this data, we are developing molecular signatures that have the ability to predict at time of diagnosis the benefit from the inclusion of radiotherapy to assist clinical decision making.