Incidental radiologic findings at breast cancer diagnosis and likelihood of disease recurrence

Joel M. Brothers, Kelley M. Kidwell, Richard K. J. Brown, N. Lynn Henry

Despite guidelines recommending against its routine use, perioperative imaging for distant metastases is frequently performed in newly diagnosed breast cancer patients, uncovering incidental findings of uncertain significance. We assessed the clinical significance of incidental findings by determining if their presence is associated with disease recurrence. A retrospective review of staging imaging was performed in patients with stage II or III invasive breast cancer diagnosed during 2008-2009 at a large academic medical center. Data related to perioperative imaging and disease recurrence were abstracted from the medical record. Kaplan-Meier curves and Cox proportional hazards models were used to assess the association between incidental findings and time to disease recurrence. A total of 169 of 340 patients (49.7 %) underwent staging evaluation for distant metastases (CT chest, abdomen, pelvis, bone scan, and/or PET-CT). Of these, 146 (86.4 %) had at least one suspicious or indeterminate finding. Follow-up studies were performed in 73 (43.2 %) patients. Nineteen patients were diagnosed with metastatic disease at diagnosis, 18 of whom had stage III disease. In patients without metastatic disease at diagnosis, 32 later developed recurrence. Non-calcified pulmonary nodules were associated with shorter time to disease recurrence (hazard ratio 2.51, 95 % CI 1.13-5.57, p = 0.02). Imaging for distant metastases frequently reveals indeterminate findings, most of which are not associated with disease recurrence. The association between pulmonary nodules and recurrence warrants validation in an independent cohort. Overall, these findings support current guidelines recommending against routine extent of disease evaluation in patients with newly diagnosed stage II breast cancer.