Breast cancer is the most common cancer in women and a leading cause of cancer death worldwide. The management of breast cancer depends on clinical and pathologic prognostic factors that help guide patient treatment. Ductal carcinoma in situ (DCIS) is a noninvasive form of breast cancer with an unpredictable risk of either progression to invasive disease or recurrence. To evaluate the utilization of the DCIS score in a large single-institution population and understand reasons for avoidance in eligible patients.Methods
A retrospective chart review of eligible patients with pure DCIS treated by lumpectomy (January 2011–May 2015) was performed. Patients were considered eligible for the assay if they met the Eastern Cooperative Oncology Group E5194 pathology criteria. All of the patients underwent breast-conserving surgery and were estrogen receptor positive.Results
Of 182 estrogen receptor–positive patients with DCIS who underwent breast-conserving surgery, 31 (17%) had a DCIS assay performed; however, most of the patients did not have a DCIS score assay performed, yet 47.9% of this cohort would have met the pathologic eligibility criteria. Conversely, 82.5% of the patients having the DCIS score evaluated actually met these criteria.Conclusions
Tumor size, grade, ER status, and calcifications were drivers of patient selection for 12-gene assay use. E5194 eligibility criteria selected for low risk population. Although a large proportion of patients met eligibility criteria, DCIS Score was infrequently considered for recurrence risk estimation. When performed, assay scores supported omission of radiation for over 75% of cases.