Cancers of the breast are the second most common type of breast cancers (after invasive ductal carcinoma, IDC) and account for 10-15% of all breast cancers. More than any other breast cancer, lobular cancers present as multifocal, multicentric and bilateral disease. Among histological types, re- excision rates are highest (28.3%) for invasive lobular carcinoma and substantially more than invasive ductal carcinoma (19.1%). For subjects diagnosed with lobular carcinoma, breast MRI is currently the preferred modality for evaluating disease extent as ultrasound and mammography have been shown to be inferior in accurately estimating tumor size. Meta-analysis of pooled data have shown that breast MRI has a sensitivity of 93.3% for detecting lobular carcinoma with additional lesions detected in 32% and 7% of patients in the ipsilateral and contralateral breasts, respectively. However, for approximately 25% to 35% of tumors, the size estimated from breast MRI differs from pathology by more than 1 cm. The use of pre-operative breast MRI for evaluating disease extent has been associated with increased odds for mastectomy. A recent study analyzing 243 patients with invasive lobular carcinoma (ILC) concluded that ILC can be safely treated with conservative surgery but a more accurate preoperative evaluation of tumor size and multifocality is needed to reduce re-excision rate. We hypothesize the high spatial resolution 3D imaging provided by dedicated breast CT that is capable of resolving features in the 200 to 250 microns range would improve the proportion of tumors that are concordant in size with histopathology and hence would increase the likelihood of subjects being treated with breast conserving surgery. Dedicated breast CT does not require physical compression of the breast and takes 10 seconds for a scan. This prospective clinical study is designed to address if all foci observed with contrast-enhanced breast MRI are also visible with contrast-enhanced breast CT (sensitivity) and if the tumor size determined from breast CT is more concordant with pathology than breast MRI. The study will also investigate two automated segmentation and tumor size quantification methods to determine, which quantitative algorithm is more accurate, with tumor size from surgical pathology serving as reference standard. Thus, the proposed study challenges existing paradigms on the accuracy of tumor size measurements and paves for the way for reducing mastectomy rates.

Public Health Relevance

Lobular cancers of the breast are the second most common type of breast cancers. More than any other breast cancer, lobular breast cancers occur in both breasts and at multiple locations. Currently, breast MRI is considered the best imaging modality for evaluating if lobular breast cancer is present in both breasts and its location(s), and determining the size or extent of the cancer. However for 26% of the tumors, the size estimated by MRI differs from pathology after surgery by more than 1 cm. Improving the accuracy of tumor size estimate is important to determine if the patient is eligible for treatment that conserves the non-cancerous breast tissue. Dedicated breast computed tomography (CT) provides much higher spatial resolution than MRI. It does not require breast compression and each scan takes 10 seconds. Hence in this research, the ability of contrast-enhanced breast CT to provide more accurate estimate of tumor size than contrast-enhanced breast MRI will be investigated.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA195512-02
Application #
9036962
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Henderson, Lori A
Project Start
2015-04-01
Project End
2017-03-31
Budget Start
2016-04-01
Budget End
2017-03-31
Support Year
2
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Massachusetts Medical School Worcester
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
603847393
City
Worcester
State
MA
Country
United States
Zip Code
01655
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Vijayaraghavan, Gopal R; Vedantham, Srinivasan; Kataoka, Milliam et al. (2017) The Relevance of Ultrasound Imaging of Suspicious Axillary Lymph Nodes and Fine-needle Aspiration Biopsy in the Post-ACOSOG Z11 Era in Early Breast Cancer. Acad Radiol 24:308-315
Shi, Linxi; Vedantham, Srinivasan; Karellas, Andrew et al. (2017) X-ray scatter correction for dedicated cone beam breast CT using a forward-projection model. Med Phys 44:2312-2320
Shi, Linxi; Vedantham, Srinivasan; Karellas, Andrew et al. (2016) Library based x-ray scatter correction for dedicated cone beam breast CT. Med Phys 43:4529
Vedantham, Srinivasan; Shrestha, Suman; Karellas, Andrew et al. (2016) Photon-counting hexagonal pixel array CdTe detector: Spatial resolution characteristics for image-guided interventional applications. Med Phys 43:2118