The Power of Annotation
The Importance of Detecting Small Lesions:
The 5-year survival rate for a breast cancer diagnosis, when detected in a lesion that is less than 10 millimeters, is 93%. The 5-year survival rate falls to 71% if cancer is detected in a 30 to 39-millimeter lesion (1).
Tens of millions of breast ultrasound procedures are performed each year globally of which millions are estimated to result in the detection of small lesions, many smaller than one centimeter. These tiny lesions need to be precisely mapped to enable re identification at follow-up or at time of biopsy and to ensure the target of interest is found and not mistaken for other abnormality with a similar appearance.Millions of small breast lesions are also detected with mammograms and MRI; theses multiple imaging modalities used in cancer diagnosis and screening depend on inter-modality correlation with breast ultrasound to decrease false-positive results, which lead to additional exams and unnecessary biopsies. Of the millions of small lesions, hundreds of thousands are expected to be breast cancers ready to be diagnosed at an early stage, upon biopsy. Multi-modality correlation is also needed to perform ultrasound-guided biopsies of targets initially found in mammograms or MRI exams, and which are generally preferred by physicians and patients.
The data from ACRIN 6666, the NIH sponsored landmark study on breast ultrasound screening, shows that 38.7% of probably benign lesions requiring follow up are classified as “no longer present” at the time of a subsequent exam (2). This is most likely because many small lesions are very difficult to find with current technology. Overall, more than 50% of lesions less than 9 mm are missed during whole breast ultrasound exams (3).
Only 50-60% of MRI lesions are found with subsequent ultrasound exams (5) and only approximately 46% of detectable ultrasound lesions are found and correctly matched with mammograms(6).
The national expenditure for false-positive mammograms and breast cancer over-diagnoses is estimated at $4 billion a year (4)
Accurate and precise mapping (position annotations) of small breast lesions is essential to perform the re identification of lesions or multimodality correlation. Today’s medical ultrasound equipment is simply inadequate in this regard due to the unresolved effect of breast deformation and tissue motion.
Existing annotation technology provides little more than input fields, into which the operator types in the (estimated) distance of a lesion to the nipple as well as the clock-face-position of the lesion, with respect to the nipple. However, millimeter 3-D positional precision is needed to reliably correlate with other breast imaging modalities for precise diagnosis or re-identification of small lesions.
The MetriTrack BVN™ G-1000 is designed to record the three-dimensional millimeter-resolution annotation of any breast lesion seen in ultrasound images with the simple touch of the BVN™ screen. The BVN™ G-1000 is compatible with most existing installed medical ultrasound equipment.
1. CANCER: Volume 104: Number 6-- September 2005.
2. Radiology: Volume 269: Number 3—December 2013.
3. Radiology: Volume 241: Number 2—November 2006
4. Health Affairs April 2015 vol. 34 no. 4576-583
5. MR-Directed (“Second-Look”) Ultrasound Examination for Breast Lesions Detected Initially on MRI: MR and Sonographic Findings, Hiroyuki Abe et al, AJR:194, February 2010
6. Occult breast masses: use of a mammographic localizing grid for US evaluation. W F Conway, C W Hayes, and W H Brewer, Radiology, vol.181, 1991.