Cancer Genetics and Epigenetics 2017, Vol.5, No.3, 11-16
12
2 Accessory Examination and Biopsy
2.1 Imaging examination
2.1.1 Molybdenum target
X-ray mammography is the golden standard for imaging diagnosis of breast related diseases. X-ray
mammography can detect tiny nodules of 2-3 mm, and can show abnormal calcification. The main X-ray features
were clusters of small calcifications, small nodules, irregular boundaries, structural disorders of the breast,
enlarged axillary lymph nodes and abundant blood flow. Spicule sign is also an important sign of occult breast
cancer. In addition, sediment like, needle like, clubbing calcification in X-ray examination also suggest breast
cancer. Generally, 15 calcifications per square centimeter can be the standard, and more than 15 can be suspected
as breast cancer.
2.1.2 Ultrasound
Ultrasound make up for gaps and omission of mammography, which can detect the edge of breast dysplasia, small
breast or chest wall tumor and other blind spots. Ultrasound and mammography is complementary, which improve
the sensitivity of detecting breast cancer lesions. Ultrasound has stronger ability to identify soft tissue, and it is
better than mammography in distinguishing low echo mass and understanding lymph node metastasis. It can
effectively observe the enlargement of axillary lymph nodes. Doppler showed that the axillary lymph nodes of
OBC were very rich in blood flow, and the structures of the cortex and medulla were separated, and the lymph
node hilus were not clear.
2.1.3 MRI
The sensitivity of breast MRI to breast cancer was 85%-100%, and the specificity was 37%-97%. MRI plays an
important role in the search for primary lesions. The advantages of MRI include non-ionizing-radiation,
noninvasive, high sensibility, high accuracy, and high localization. MRI is good for soft tissue, especially for deep
breast lesions. The number, range and size of lesions can also be evaluated by MRI.
2.1.4 PET-CT
PET can detect tumor growth from molecular level, and help to find metastases from other parts of body. It is
reported that PET can detect the abnormal metabolism of mammary gland without abnormal anatomical structure
(Ramírez et al., 2014), the sensitivity is 62%-100%, the specificity is 96%-100% (Cenzano et al., 2012). But the
price is too expensive, and PET technology successful detecting OBC cases was rarely, bringing about detection
space is still limited.
2.1.5 Breast-specific gamma imaging (BSGI)
BSGI as a high resolution imaging type, can detect sub centimeter level occult breast cancer, whose sensitivity
and specificity is better than MRI. BSGI can detect tiny cancer foci in dense breast (Brem et al., 2016).
2.2 Needle biopsy
2.2.1 Fine needle aspiration cytology (FNAC)
The technique is suitable for the puncture of enlarged axillary lymph nodes, and the suction cells are examined by
liquid based cytology, which can detect whether there are tumor cells.
2.2.2 Core needle biopsy (CNB)
This examination is a pathological biopsy of histology, and it is a common method to detect the primary breast
cancer before operation. Axillary lymph node puncture should be performed under ultrasound guidance so as not
to damage axillary vein.
2.2.3 Breast MRI localization biopsy
MRI found occult breast cancer suspicious malignant lesions, which need further MRI positioning biopsy, MRI
showed OBC lesions characterized by mass like irregular ring enhancement, or non mass like irregular
heterogeneous enhancement (Tandon et al., 2016). MRI is more accurate and safe for location of tiny lesions (Gao
et al., 2016).
