Abstract P3-02-04: Is breast magnetic resonance imaging (MRI) useful for diagnosis of additional sites of disease in patients recently diagnosed with ductal carcinoma in situ (DCIS)?

Purpose: To determine if breast MRI is useful for detecting additional sites of disease in patients initially diagnosed with pure DCIS. Materials and Methods: A retrospective review of women diagnosed with pure DCIS who underwent a breast MRI for evaluation of extent of disease was performed at a single institution from January 2013 to April 2015. Data analysis included imaging (mammography, ultrasound and MRI) and pathology characteristics (histology and biomarker status) of the primary DCIS as well as descriptors for the additional sites of disease incidentally found by breast MRI. Results: A total of 94 patients were diagnosed with pure DCIS during this time period, ages ranging from 38 to 79 years old (median, 58.5 years); sizes ranging from 0.6 to 16 cm (mean, 4.5 cm). A total of 28 patients (30%) had other MRI findings suspicious for additional sites of disease in either breast. From this group of patients, 23 (82%) patients underwent MRI-guided biopsy. The 5 patients who did not have the MRI guided-biopsy either underwent total mastectomies or declined biopsy. Five out of the twenty-three patients (22%) were diagnosed with an additional site of cancer. Three of these patients were Hispanic, one was Asian/Pacific and one was Caucasian. Of the five patients, five had contralateral disease (100%) and none had a second site of disease in the ipsilateral breast. The size of the additional sites of disease ranged from 0.4 to 7.2 cm (mean, 2.1 cm) and the size of the primary lesion in this selected group ranged from 0.4 to 9 cm (mean, 3.4 cm). Ages ranged from 47 to 63 years old (median, 55 years). Four out of five patients (80%) presented with the first site of disease as pure DCIS with estrogen (ER) and progesterone (PR) receptors positive and one case (20%) was pure DCIS ER/PR- negative. The second incidental lesion found on MRI demonstrated 3 cases of contralateral pure DCIS. From this group, all the biomarkers status for the first and second site were concordant. From the 5 cases of second disease, 2 (40%) presented with invasive component in the contralateral side of the initially biopsy-proven pure DCIS and, one of these cases had discordant biomarkers compared with the first site of disease, the first site of pure DCIS was ER/PR-negative and the second site of invasive ductal carcinoma (IDC) presented with ER/PR-positive status. Conclusion: From a total of 94 patients with recent diagnosis of pure DCIS who underwent breast MRI examination for diagnosis of additional sites of disease, approximately 5% were diagnosed with an additional site of cancer and 2% of the total cases had invasive disease in the additional sites with different biomarker status; changing their management and prognosis. Breast MRI plays a role in the setting of staging patients initially diagnosed with pure DCIS. Citation Format: Ortiz-Perez T, Benveniste AP, Ebuoma LO, Sepulveda KA, Severs FJ, Kapoor M, Sedgwick EL. Is breast magnetic resonance imaging (MRI) useful for diagnosis of additional sites of disease in patients recently diagnosed with ductal carcinoma in situ (DCIS)? [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-02-04.