.jpg)
Doctors newspaper online, 05.07.2019
risk patients
Magnetic resonance imaging (MRI) is at the heart of risk-adapted early breast cancer detection. Tomosynthesis is on the way to improving mammography screening in the overall population. The details are discussed.
By Beate Fessler
BERLIN. While population-based mammography screening focuses on reducing mortality in the overall population, minimizing individual mortality is the goal of risk-adapted early detection.
"We have a high responsibility for a small number of pre-loaded patients," said Professor Ulrich Bick from the Department of Radiology at the Charité Berlin at the 39th Annual Meeting of the German Society of Senology in Berlin at the end of June.
According to Bick, these women need a procedure that finds as many carcinomas as possible. Only MRI is able to do this: By comparing 40 carcinomas from 1356 screening rounds in 559 high-risk patients, MRI left behind mammography and ultrasound with a specificity of 88.9 percent and a sensitivity of 90 percent.
Mammography alone had a sensitivity of 37.5 percent with a specificity of 97.1 percent, in combination with ultrasound a sensitivity of 50 percent with unchanged specificity.
MRI yes, but not at low incidence
According to Bick, annual contrast-enhanced breast MRI is the core building block of any intensified breast cancer screening in high-risk patients. "In BRCA1 / 2-negative patients, advanced tumor stages can be virtually completely prevented."
In BRCA1 / 2-positive patients, intensified early detection often only serves to bridge the time to perform risk-reducing surgeries. However, MRI-based early detection is only useful if the breast cancer incidence is sufficiently high.
"At low incidence, MRI-based screening does not make sense," said Bick. This applies, for example, to patients with a positive family history (BRCA1 / 2 negative) between the ages of 30 and 39 years.
Gadolinium: "no problem" in breast MRI
Contrast enhancement on MRI is achieved with gadolinium-containing contrast agents – also on MRI of the breast. Gadolinium is discussed controversially, among other things because of possible deposits in the brain.
Professor Matthias Dietzel, radiologist at the University of Erlangen, however, sees "no problem" in the use of gadolinium in the risk-adapted early detection of breast cancer.
He referred to the extremely large experience with gadolinium-containing contrast agents, which show little general side effects. Serious side effects are extremely rare. The risk of a fatal outcome is about 1 per 1,700,000, explained Dietzel in Berlin.
An association of gadolinium-containing contrast agents and NFS (nephrogenic systemic fibrosis) is known. It is dose-dependent, occurs in association with renal insufficiency, and is more common in linear than in macrocyclic contrast media. Accordingly, it is important to clarify renal insufficiency and to use a minimal dose and macrocyclic contrast media.
The risks should be weighed and alternatives considered. However, according to Dietzel, the risk for an NCCR is easily delimited and effectively controlled.
Least amounts deposited
Gadolinium deposits can be found "with extreme techniques" in the organism in certain constellations, depending on the type and dose of the contrast agent or also on an existing CNS disease. According to Dietzel, however, the amounts are "lowest" and deposited outside the brain parenchyma.
A first prospective study on gadolinium deposits in the risk-adapted early detection of breast cancer comes to the conclusion: After many MRI and very high doses of a macrocyclic contrast agent, no changes in the brain can be detected.
Tomosynthesis is already being used in the diagnostic evaluation. Their role in primary diagnostics is currently under intense scrutiny, for example in the TosyMa study and the Oslo Tomosynthesis Screening Trial, whose data were published in February ( Radiology 2019; 291 (1): 23-30 ).
What you can say so far, Dr. Heike Preibsch, radiologist at the University Hospital Tübingen: Tomosynthesis can increase sensitivity and specificity in screening, with an increased clarification rate, especially in dense breasts.
More invasive and nodal-negative carcinomas are detected, as well as more G1 carcinomas. Still unclear is the effect on the reinstatement rate. An influence on the interval carcinoma rate was not observed.
More articles from this topic
No comments:
Post a Comment