Clinical Report on the First Prototype of a Photoacoustic Tomography System with Dual Illumination for Breast Cancer Imaging.
Photoacoustic tomography is a recently developed imaging modality that can provide high spatial-resolution images of hemoglobin distribution in tissues such as the breast. Because breast cancer is an angiogenesis-dependent type of malignancy, we evaluated the clinical acceptability of breast tissue images produced using our first prototype photoacoustic mammography (PAM) system in patients with known cancer. Post-excisionally, histological sections of the tumors were stained immunohistochemically (IHC) for CD31 (an endothelial marker) and carbonic anhydrase IX (CAIX) (a marker of hypoxia). Whole-slide scanning and image analyses were used to evaluate the tumor microvessel distribution pattern and to calculate the total vascular perimeter (TVP)/area for each lesion. In this clinical study, 42 lesions were primarily scanned using PAM preoperatively, three of which were reported to be benign and were excluded from statistical analysis. Images were produced for 29 out of 39 cancers (visibility rate = 74.4%) at the median depth of 26.5 (3.25-51.2) mm. Age, menopausal status, body mass index, history of neoadjuvant treatment, clinical stage and histological tumor angiogenesis markers did not seem to affect the visibility. The oxygen saturation level in all of the measured lesions was lower than in the subcutaneous counterpart vessels (Wilcoxon test, p value<0.001), as well as in the counterpart contralateral normal breast region of interest (ROI) (Wilcoxon test, p value = 0.001). Although the oxygen saturation level was not statistically significant between CAIX-positive vs. -negative cases, lesional TVP/area showed a positive correlation with the oxygen saturation level only in the group that had received therapy before PAM. In conclusion, the vascular and oxygenation data obtained by PAM have great potential for identifying functional features of breast tumors.
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Elham
E
Fakhrejahani
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Masae
M
Torii
Department of Surgery, Kishiwada City Hospital, Osaka, Japan.
Toshiyuki
T
Kitai
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Shotaro
S
Kanao
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Canon Inc., Tokyo, Japan.
Yasufumi
Y
Asao
Canon Inc., Tokyo, Japan.
Yohei
Y
Hashizume
Department of Diagnostic Pathology, Kumamoto University Hospital, Kumamoto, Japan.
Yoshiki
Y
Mikami
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Iku
I
Yamaga
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Masako
M
Kataoka
Department of Surgery, Kansai Medical University, Osaka, Japan.
Tomoharu
T
Sugie
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Masahiro
M
Takada
Department of Diagnostic Pathology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Hironori
H
Haga
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Kaori
K
Togashi
Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Tsuyoshi
T
Shiina
Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Masakazu
M
Toi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D003952:Diagnostic Imaging; D005260:Female; D006454:Hemoglobins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D015674:Mammary Neoplasms, Animal; D008327:Mammography / Q000379:methods; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000473:pathology; D061088:Photoacoustic Techniques; D014057:Tomography, X-Ray Computed
D006454:Hemoglobins