Visualizing typical features of breast fibroadenomas using phase-contrast CT: an ex-vivo study.
BACKGROUND
Fibroadenoma is the most common benign solid breast lesion type and a very common cause for histologic assessment. To justify a conservative therapy, a highly specific discrimination between fibroadenomas and other breast lesions is crucial. Phase-contrast imaging offers improved soft-tissue contrast and differentiability of fine structures combined with the potential of 3-dimensional imaging. In this study we assessed the potential of grating-based phase-contrast CT imaging for visualizing diagnostically relevant features of fibroadenomas.


METHODS
Grating-based phase-contrast CT was performed on six ex-vivo formalin-fixed breast specimens containing a fibroadenoma and three samples containing benign changes that resemble fibroadenomas using Talbot Lau interferometry and a polychromatic X-ray source. Phase-contrast and simultaneously acquired absorption-based 3D-datasets were manually matched with corresponding histological slices. The visibility of diagnostically valuable features was assessed in comparison with histology as the gold-standard.


RESULTS
In all cases, matching of grating-based phase-contrast CT images and histology was successfully completed. Grating-based phase-contrast CT showed greatly improved differentiation of fine structures and provided accurate depiction of strands of fibrous tissue within the fibroadenomas as well as of the diagnostically valuable dilated, branched ductuli of the fibroadenomas. A clear demarcation of tumor boundaries in all cases was provided by phase- but not absorption-contrast CT.


CONCLUSIONS
Pending successful translation of the technology to a clinical setting and considerable reduction of the required dose, the data presented here suggest that grating-based phase-contrast CT may be used as a supplementary non-invasive diagnostic tool in breast diagnostics. Phase-contrast CT may thus contribute to the reduction of false positive findings and reduce the recall and core biopsy rate in population-based screening. Phase-contrast CT may further be used to assist during histopathological workup, offering a 3D view of the tumor and helping to identify diagnostically valuable tissue sections within large tumors.
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Susanne
S
Grandl
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany.
Marian
M
Willner
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany; Institute for Materials Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany.
Julia
J
Herzen
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Anikó
A
Sztrókay-Gaul
Institute of Pathology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany.
Doris
D
Mayr
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Sigrid D
SD
Auweter
Institute for Materials Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany.
Alexander
A
Hipp
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany.
Lorenz
L
Birnbacher
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany.
Mathias
M
Marschner
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany.
Michael
M
Chabior
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Maximilian
M
Reiser
Department of Physics and Institute of Medical Engineering, Technical University of Munich, Munich, Germany.
Franz
F
Pfeiffer
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Fabian
F
Bamberg
Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Karin
K
Hellerhoff
D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D018226:Fibroadenoma / Q000000981:diagnostic imaging*; D006801:Humans; D007368:Interferometry / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*