Comparison of ABVS and HHUS
for detection and characterization of breast lesions

Breast cancer is the most common malignancy in Dutch women with a life
prevalence of 10%. A nation wide screeningsprogram *Bevolkins Onderzoek naar
Borstkanker* (in short BOB) is designed to screen in early phase to detect
breast cancer. Next to this program, breast cancer may be detected by the
finding of a palbaple breast mass. A palpable breast mass in women older than
30 years requires mammography (XMG) and ultrasound (Hand Held Ultra Sound or
HHUS). In women younger than 30 years the first diagnostic step is ultrasound
imaging. The reason therefore is that mammograms are summation images and
younger women have relatively dense breast tissue, which hampers proper
interpretation of the mammography. This makes ultrasound the first diagnostic
tool in patients <30 years. Thus, ultrasound plays an important role in the
diagnostic imaging of breast masses.

Next to this ultrasonography is also of major importance when an abnormality is
found on mammography in older women. When a mammographic abnormality is
detected, it can be difficult to precisely define and characterize, and at this
time ultrasound is used to assess the nature of a lesion, extent of disease and
it can indentify additional invasive lesions. The next advantage of ultrasound
is that it can easily be used as guidance for punctions and biopsies to acquire
histology of a lesion. The disadvantage of HHUS is that quality of imaging is
highly operator dependent and thus moderate reproducible and reliable.

Recently a new technique has been introduced, semi-automated 3-dimensional
utrasonography also called Automated Breast Volume Scan (ABVS). Using this
technique the physician assistant will set up the 3D ultrasound and automated
images of the whole breast are acquired, thus resulting in a standardized image
data set. This makes the technique operator independent and facilitates image
analysis. Previous studies are promising but small and have shown that more
relevant lesions may be detected with improved reproducibility to HHUS, however
significant conclusions could thusfare not be drawn.

1. To evaluate wether ABVS could replace HHUS in women <30 year with focal
breast signs
2. To evaluate the performance of ABVS in comparison to HHUS in patients with
high suspicion of breast cancer
3. To start a pilot study to compare ABVS with breast MRI in patients with
known breast cancer

Prospective diagnostic monocenter study.
For the 3 objectives we discriminate 3 cohorts.

A. Women < 30 year with a palpable mass. Women < 30 years who have a palbable
mass, have a low chance of having a malignancy. The general practicioner will
refer these women to the radiologist for ultrasound examination. The most
common causes of a palpable breast mass in these young patients are cystic
lesions, solid lesions and dense glandular tissue. When a solid lesion is
detected, a choice can be made between expectative policy with 6 months
follow-up or immediate biopsy. In other cases, no further follow-up is
required. HHUS will be performed by one of the staff radiologists or resident
under supervision of a staff member, such as is common in daily practice. We
strive to perform ABVS immediatly after the HHUS, but certainly within 5 days.

B. Women with a high suspicion of breast cancer. These women may have a
palpable breast mass or an abnormality was found during screening and are
usually older than 30 year. In these patients first a standard XMG is done.
However, by XMG only, it can be difficult to determine the nature of a detected
abnormality. XMG cannot certainly discriminate between a cystic or solid nature
of lesion, and also the exact extent and borderlines may be difficult to
define. Therefore ultrasound is indicated. According to the guidelines all
patients with high risk lesions require pathology-analysis by means of
histologic biopsy. Most of these biopsies are ultrasound guided. The patients
will first be send to the mammacare department for clinical examination
followed by XMG and HHUS imaging. ABVS will be performed after this
conventional imaging is performed, but always within 5 days.

C. Women with proven malignancy who require breast MRI. These patients have
already had biopsy, but pathology, clinical presentation and imaging are
incorcordant or have a suspected multifocal tumor. MRI is planned before the
proper treatment can be defined and ABVS will be performed after or before MRI,
but always within 5 days.

In all cohorts, images will be independently analysed by one the four dedicated
breast radiologists. Reporting will be perfomed according to the BIRADS
classification system, inlcuding number, characterization, classification and
location.

Both the presence of a palpable breast lesions of unknown origin as well as a
known breast tumour, carry severe distress and anxiety for most women. Next to
that patients are very worried about the required additional imaging studies
and possible biopsy. Ultrasound gives no radiation harm and has no other known
side effects. Although this study implies some extra time for the patient, the
women are ensured that both breasts are fully examined. If no lesion is found
this could be very satisfying and reassuring. On the other hand, if extra
lesions are found, immediate action will be undertaken to analyse this and make
a final decision. Finally this may results in improved diagnostics and thus
better treatment. If this is true, in future ABVS could be used to replace HHUS
and provide a better standard imaging technique.