Keywords:
Biopsy, Ultrasound, MR, Mammography, Breast, Cancer
Authors:
T. Imschweiler1, H. Haueisen2, G. Kampmann3, L. Rageth4, B. Seifert5, C. Rageth4, B. K. Chilla1, R. A. Kubik-Huch1; 1Baden/CH, 2Aarau/CH, 3Gravesano-Lugano/CH, 4Zürich/CH, 5Zurich/CH
DOI:
10.1594/ecr2013/C-0554
Conclusion
The study showed that the total number of image-guided vacuum biopsies in Switzerland remained mostly constant throughout the study period with an overall growth rate of 2%,
whereby the number of MRI-guided VAB rose significantly by 97%. The growth rate for the procedure using a stereotaxis table was 14%.
The growth rates for the procedures using an “upright” device and sonography declined by 1% and 31% respectively.
The total complication rate for MRI-guided VAB (8%) showed no significant difference from the rates for the procedure using a stereotaxis table (6%) (p=0.08) and the procedure using an “upright” device (5%) (p=0.02).
The total complication rate for the MRI-guided procedure is significantly higher (p<0.001) compared to the sonographic procedure (4%).
The majority of the complications for MRI-guided VAB consisted of haemorrhages not requiring intervention (7%).
Non-medical complications occurred 1% of the cases.
The total complication rate of MRI-guided VAB lies within the range of complication rates published in the literature (2-14%) [4-8,12].
With regard to a positive family history,
there is no significant difference between the MRI-guided procedure and the stereotactic procedure (p=0.23).
The significantly higher difference (p<0.001) with regard to a positive family history in MRI-guided VAB compared to sonographic VAB can be explained by the fact that no distinction was made between a therapeutic and diagnostic approach to vacuum biopsy and that sonographic VAB is also performed as a treatment for confirmed benign lesions.
This results in a different composition of the patient population for these two methods.
The lack of a significant difference in family history between the MRI-guided and stereotactic procedure shows that MRI has as yet not been established in Switzerland as a screening method for high-risk patients as recommended in some of the literature [9].
The significantly larger difference in the positive personal carcinoma history for a breast carcinoma in MRI-guided procedures when compared to the stereotactic (p<0.001) or the sonographic (p<0.001) procedures can be explained by the indication of the diagnostic MRI,
as this examination is indicated,
among others,
as a screening method to assess additional ipsilateral carcinomas and contralateral extension in newly diagnosed breast carcinomas,
to determine the spread of the disease and for post-examination purposes and the resulting “selection bias” [9].
The malignancy rate after MRI-guided VAB was 26%;there was no significant difference (p=0.35) compared to that of stereotactic VAB (24%).
The malignancy rate of sonographically guided VAB was12% and was therefore significantly (p<0.001) lower compared with the MRI-guided procedure.
This is due to the lack of distinction between diagnostic and therapeutic sonographic vacuum biopsy as metioned above.
The malignancy rate of MRI-guided VAB corresponds with the malignancy rates of 22-33% from the literature [6,7,10-13].
A limiting factor of this study is that the data was recorded by the individual MIBB centres in Switzerland,
making errors in data input conceivable.
This was particularly conspicuous in the histological results,
as conflicting information was found.
Due to the anonymised data situation,
elimination of errors by viewing the original findings is not possible.
On the other hand,
the large number of participating centres resulted in the availability of a very large volume of data on which this study was based,
which provides an advantage over other studies with partly significantly smaller case numbers.
In summary MRI-guided VAB is a safe and specific procedure has the largest growth rate in Switzerland and is the method of choice for ambiguous breast findings which can only be defined by the use of MRI.