Abstract P2-02-06: Breast cancer in the elderly: Is MRI helpful?
Authors: Pilewskie M , Hirsch A , Eaton AA , Stempel M , Morris E , Gemignani ML 
Published: August 2014

Background: Guidelines support screening MRI in select high-risk groups; however, MRI is frequently obtained perioperatively and for breast cancer (BC) follow-up. Appropriate use of MRI in elderly patients remains unclear; we sought to identify the indications and implications of MRI use in our elderly BC population.

Methods: Women 70 years of age or older at first BC diagnosis with an MRI performed at our institution either perioperatively or in follow-up were included from a prospectively maintained database from 2000-2010. Univariate logistic regression was used to test associations with upgrade (additional ipsilateral, contralateral, new cancer, or recurrence) following perioperative MRI. Kaplan-Meier and competing risks methods were used to estimate survival and cumulative incidence.

Results: 305 breast cancers were identified in 286 patients. 133 patients were imaged with an MRI in the perioperative setting alone, 88 had only follow-up MRIs after BC treatment, and 65 had both. Patient, tumor, and treatment data are summarized in Table 1.

TableFactorN = 305Age, yearsMedian: 73 (range, 70-90)Means of Diagnosis Imaging189 (62%)Physical abnormality109 (36%)Other/incidental7 (2%)Mammographic density* Fatty21 (7%)Mild96 (32%)Moderate166 (55%)Extreme18 (6%)Tumor size*Median: 1.2cm (range 0.1-7.0)Histology DCIS +/- microinvasion44 (14%)Invasive ductal181 (59%)Invasive lobular68 (22%)Other12 (4%)ER positive*225 (86%)PR positive*159 (61%)HER2/neu positive*17 (7%)Final surgery* Lumpectomy217 (71%)Mastectomy87 (29%)Radiation following lumpectomy*169 (80%)Adjuvant chemotherapy*81 (27%)Adjuvant endocrine therapy*200 (69%)*for patients with information available 

Indications for perioperative MRI include: extent of disease evaluation for known cancer (155;78%); abnormal imaging (13;7%); protocol (13;7%); occult primary (10;5%); high-risk screening (5;3%); and abnormal physical exam (2;1%). MRI upgrade for occult primary cases was 4/10 (40%; 95% confidence interval (CI), 12.2-73.8%) and 21/188 (11.2%; 95% CI, 7.1-16.6%) for the remainder of perioperative cases; comprised of 9 contralateral and 5 additional ipsilateral cancers in women undergoing MRI for extent of disease evaluation, and 7 new cancers identified on MRIs for high-risk screening or abnormal imaging/physical exam. These lesions consisted of 10 DCIS and 11 node-negative invasive cancers (median size, 7mm; range, &lt;1-18mm). Analysis of imaging and tumor characteristics failed to find significant predictors of upgrade. 369 postoperative follow-up MRIs were performed in 153 patients with a median of 2 MRIs per patient (range, 1-8), and identified 7 upgrades (1.9%; 95% CI, 0.8-3.9%), for an overall patient upgrade rate of 4.6% (7/153). Median follow-up was 5.3 years. Five-year incidence of local, regional, and distant recurrence, and contralateral BC was 3.3%, 1.3%, 4%, and 3.7%, respectively. Five-year overall and recurrence-free survival (RFS) was 92% and 85.7%, respectively.

Conclusion: Our elderly patients had an excellent overall and RFS. MRI had the greatest benefit in women presenting with an occult primary. 11% of perioperative MRIs identified additional or new disease, while only 2% of follow-up MRIs resulted in an upgrade, calling into question the benefit of follow-up MRI imaging in elderly BC patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-02-06.