Imaging the Patterns of Breast Cancer Early Metastases

Overview

Currently, once a distant breast metastasis has been diagnosed, 65% of patients will succumb to their cancer within 2 years, and 80% will succumb by 5 years. The current National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines for Breast Cancer do not recommend surveillance imaging for earlier detection of distant metastases, even for high-risk breast cancer patients. Whereas, the standard-of-care treatment of the small isolated (few in number) breast cancer metastases is to perform surgical resection or locally ablative radiation therapy, however, the follow-up of breast cancer patients (including those with a \>= 30% risk of developing metastases) is to wait for clinical symptoms to appear before using a dual positron emission tomography (PET) and diagnostic quality computed tomography (CT) PET/CT scan, magnetic resonance imaging (MRI), computed tomography (CT) or a bone scan to identify the site and extent of spread. Unfortunately, once metastases become symptomatic they are often too large and/or numerous to treat with curative intent. The current national care guidelines that advocate against intensive surveillance for distant metastases are based on two studies performed in Italy from 1985-1993 that concluded that the available imaging and treatment tools of the day did not prolong 5-year survival. Since then, however, there have been major improvements in imaging and treatment technology. To be treatable the metastases must be limited in number and limited in size, typically 6 or fewer metastases, each of size 5 centimeter or less. This state of metastatic presentation is called oligometastases. Numerous pilot studies have achieved dramatically improved overall and disease-free survival when oligometastases are treated using a combined systemic plus locally-ablative therapy of each oligometastasis. A scientific concern with the aforementioned research studies involving ablation of isolated oligometastases, was that they were not carried out with consistent use of surveillance imaging. Instead, these studies effectively preselected patients for enrollment based upon having an existing oligometastatic presentation. The primary objectives of the research study are to: (1) determine the feasibility of the stated interventions in a multi-institutional setting; (2) document the patterns of early metastatic spread of breast cancer; (3) document the proportion of high-risk breast cancer patients that have an oligometastatic presentation within this proactive imaging protocol, and (4) provide a basis to determine how to optimize future surveillance imaging protocols with respect to the time to progression, rate of tumor growth and organs that are affected.

All enrolled subjects will undergo a single whole-body dual positron emission tomography (PET) and diagnostic quality computed tomography (CT) PET/CT scan and a CT scan with contrast acquired in the same imaging session; and a single brain magnetic resonance imaging (MRI) scan with contrast to be completed in separate imaging session but within 2 weeks of the PET/CT scan. Imaging will take place within 7 months after enrollment. In addition, the medical records related to the breast cancer and care, obtained and maintained as per standard-of-care, will be monitored for up to 5 years. In this research study the investigators will acquire a PET/CT image of the body (neck to mid-thigh) using best-practice diagnostic imaging protocols, typically involving 64-slice CT systems, 1x1x3 mm voxel dimensions, use of non-ionic contrast agents, and breath-holding for motion correction. Subjects will also receive a single MRI with injected contrast of the brain using best-practice diagnostic imaging protocols, typically involving a 3-Tesla clinical MRI system.