The DCISionRT Registry

This is a prospective cohort study conducted within the medical network of the participating
investigators and institutions. Patients meeting the eligibility criteria outlined above will
be eligible for participation and the investigators will obtain written informed consent. A
central Institutional Review Board (IRB) will approve the protocol and each participating
institution.

After diagnosis of DCIS, the most representative tissue block (or 10 sections mounted on
charged slides cut at 3 microns) will be sent to PreludeDx for DCISionRT. The most
representative specimen should be selected from tissue collected via direct tumor biopsy
(either FNA, core needle or excisional biopsy) as part of routine patient care. Patients must
be enrolled in the study and the enrollment and pre-testing data forms must be completed and
submitted before the DCISionRT results are reported. Then, after review of the DCISionRT
results, the investigators complete and submit the post-testing data form. The patient may
then be followed for up to 10 years (or until death) with completion of a yearly follow-up
form.

All study data will be stored in an encrypted, HIPAA-compliant database maintained by the
coordinating center. Each consented patient will be assigned a unique Study ID number. Study
personnel at each institution will maintain an electronic key to link the Study IDs of its
own patients to the patients' local medical record number. All personal health information
(PHI) will remain at the local institution and only de-identified data will be uploaded to
the national registry. No genetic test results that may be used to identify the patient will
be included in the database.

This study anticipates the participation of 25 to 100 sites within the United States with
each site enrolling between 10 and 100 patients. The study is designed to collect information
for up to 2,500 patients.

The purpose of this study is to create a de-identified database of patients, test results,
treatment decisions and outcomes that can be queried to determine the clinical utility of the
DCISionRT™ Test in the management of DCIS, as it is broadly incorporated into clinical
practice. The primary objective is to identify a statistically significant difference in
physician treatment recommendations for patients diagnosed with DCIS and treated with breast
conserving surgery based on availability of the DCISionRT test results. The primary endpoints
are treatment recommendations according to standard procedure at each clinical site both pre-
and post-DCISionRT results.

Secondary endpoints include the percent of patients for which the recommended treatment
before DCISionRT results and after DCISionRT results differ as a function of clinical
factors, such as age groups (<40, 40-50 and >50), grade (I, II, III), and tumor size (>1cm,
>2.5cm, >4cm). Other analyses involve the identification of key driver(s) of treatment
recommendation, such as age, ethnicity, race, family history, presentation
(screening/clinical), grade, architecture, necrosis, tumor size, palpability, number of
excisions, surgical margin, hormone receptor status, HER2 status; distribution of DCISionRT
scores across the cohort; and identification of key driver(s) of treatment recommendation
based on geographic region of the investigator.

The study population will be selected from the clinical practices of the participating
investigators and institutions. Patients who have been recently diagnosed with DCIS and are
being evaluated for the need for further therapy will be screened for eligibility per the
following eligibility criteria.

Inclusion criteria

- Patient must have histologically confirmed ductal carcinoma in situ (DCIS) in a single
breast (presence of lobular carcinoma in situ (LCIS) or other benign breast disease in
addition to DCIS is acceptable)

- Patient must have the DCISionRT™ Test ordered during routine patient care

- Patient must be planning to undergo breast conserving surgery

- Patient must be eligible to receive radiation and/or systemic treatment

- Patient must be greater than 25 years old

- Patient must have been diagnosed with DCIS within 120 days of consent

- Patient must be able to provide informed consent

Exclusion criteria

- Patient tissue is insufficient to generate DCISionRT test results or required
DCISionRT inputs (age, tumor size, margin status, palpability) are missing

- Patient has evidence of invasive breast cancer, including microinvasion, lymph node
involvement, or Paget's disease of the nipple or suspicious mammogram findings in the
lymph nodes or contralateral breast

- Patient has been surgically treated with a mastectomy for primary DCIS

- Patient has prior in situ or invasive breast cancer

- Patient is pregnant

- Patient was previously enrolled onto this registry