Question

Is screening by ultrasound a viable way of determining breast cancer?

Recommendation

Screening by ultrasound is not recommended in the general population.

 

Screening by ultrasound for women with an elevated risk is only recommended when other forms of screening cannot be used.

Conclusions

The added cancer detection yield from screening with ultrasound added to mammography is on average 4.2 cancers for every 1,000 women with an elevated breast cancer risk and dense glandular tissue, but also leads to a substantial increase in false positives.

Level 1: A2 Berg 2008, Berg 2009

 

If mammography screening is combined with MRI screening, ultrasound screening has no added value.

Level 3: A2 Berg 2009

 

Ultrasound screening in women with a lifetime risk of <15% who do not have dense glandular tissue has no added value.

Level 3: A2 Berg 2009

Literature summary

Results of the 14-centre study [ACRIN 6666 trial; Berg, 2008] were published in 2008, comparing cancer detection by means of screening mammography with that of screening mammography plus screening by ultrasound. The study population consisted of 2,809 women who had heterogeneously dense glandular tissue in at least one quadrant. Almost all the women had an elevated risk of breast cancer with an RR of 2.5 or more. Using mammography, cancer detection was 7.6 per 1,000. By adding ultrasound to the screening, this figure rose by 4.2, reaching 11.8 per 1,000 (95% CI 1.1-7.2). The average size of the tumours detected by ultrasound was 10 mm, 92% were invasive, 89% were lymph node negative. The positive predictive value (PPV) of the mammography was 22.6%; after adding ultrasound this fell to 11.2%. The average duration of the ultrasound examination was 19 minutes, not including time for comparison with earlier examinations, contact and discussions with the patients, or reporting time. A follow-up study into the cost-effectiveness is in progress. In a single-centre study, 6 cancers were found in 1,862 women who underwent an ultrasound screening performed by radiology technicians.

The results may be compared with 6 previously published single-centre studies. In these studies a total of 42,838 ultrasound screening exams were performed, from which a total of 150 cancers were found in 126 women. Ninety-four percent (94%) were invasive and 70% were less than 1 cm [Kolb, 2002; Buchberger, 2000; Crystal, 2003; Gordon, 1995; Kaplan, 2001; Leconte 2003]. In these studies, as well, there were women with an elevated risk and dense glandular tissue. In 5 studies, women with an elevated risk underwent mammography, ultrasound, and MRI. The combined sensitivity of mammography and ultrasound was 52%, the combined sensitivity of mammography and MRI was 92.7%. The percentage of false positives was higher than with MRI [Kuhl, 2005; Lehman, 2007; Sardanelli, 2007; Warner, 2004; Berg, 2009].

Considerations

Just as in the 14-centre trial, in the Netherlands a radiologist performs the ultrasound examination of the breast, preferably the same radiologist who supervises and interprets the mammogram. Screening by a medical specialist, including the increase in the number of biopsies, is probably not cost-effective. There are developments in progress, for example in the area of automated ultrasound systems, to handle the practical application problems, but the image resolution with these systems is not yet state of the art. Training of special staff can also be considered. It must also be realised that the results of studies always give a somewhat flattering picture compared to daily practice, in which there is no controlled or standardised way of working. The study population consisted only of women with an elevated risk of breast cancer and dense glandular tissue in at least one quadrant. Nevertheless, based on this study ultrasound screening could be considered in individual cases, if other imaging techniques are not possible.

Digitisation has increased the interpretability of dense glandular tissue, and its sensitivity is also increased by the presence of earlier images [Barlow, 2002]. The results of the cost-effectiveness study that will comprise the final part of the 14-centre trial are important in helping to define the subgroup of patients who are eligible for this form of screening, for lack of better modalities.

Authorization date and validity

Last review : 13-02-2012

Last authorization : 13-02-2012

The national Breast Cancer guideline 2012 is a living guideline, in other words there is no standard term of revision. NABON continually watches at new developments and clinical problems in the areas of screening, diagnostics, treatment and aftercare, and whether this requires an update.

Initiative and authorization

Initiative : Nationaal Borstkanker Overleg Nederland

Authorized by:
  • Nederlandse Internisten Vereniging
  • Nederlandse Vereniging voor Heelkunde
  • Nederlandse Vereniging voor Psychiatrie
  • Nederlandse Vereniging voor Radiologie
  • Nederlandse Vereniging voor Radiotherapie en Oncologie

General details

Approximately 14,000 women (and 100 men) are diagnosed with invasive breast cancer each year in the Netherlands, and about 1,900 have an in situ carcinoma. A woman's risk of having breast cancer over the course of her life is 12-13%. This means that breast cancer is the most common form of cancer in women in the Netherlands. Early detection, particularly via national breast cancer screening, combined with adjuvant therapy followed by locoregional treatment, improves the prognosis in women with breast cancer

The guideline on Breast Cancer Screening and Diagnostics, published in 2000, was updated in 2007. In 2002, the first multidisciplinary National Breast Cancer Guideline was published, it was revised in 2004, 2005 and 2006. In 2008 both guidelines were combined to Breast Cancer Guideline, which 2012 revision is now effected.

Scope and target group

This guideline is written for all the members of the professional groups that have contributed to its development.

 

This guideline is a document with recommendations and instructions to support daily practice. The guideline is based on the results of scientific research and expert opinion, with the aim of establishing good medical practice. It specifies the best general care for women with (suspected) breast cancer and for those who are eligible for screening. The guideline aims to serve as a guide for the daily practice of breast cancer screening, diagnostics, treatment and aftercare. This guideline is also used in the creation of informational materials for patients, in cooperation with the KWF (Dutch Cancer Society).

Member of workgroup

A core group consisting of a radiologist, surgeon, pathologist, medical oncologist and radiation therapist began preparing for the revision of the breast cancer practice guidelines in 2009. A multidisciplinary guideline development group was formed in early 2010 to implement the revision. This group consisted of mandated representatives from all of the relevant specialisations concerned with breast cancer, plus two delegates from the BVN (Dutch Breast Cancer Society) (see list of guideline development group members). The benefits of such a multidisciplinary approach are obvious: not only does it best reflect the care, but it offers the greatest possible expertise for the guideline. In composing the development group, geographic distribution of the members, balanced representation of the various organisations and agencies concerned, and a fair distribution in academic background were taken into account as much as possible.

 

The guideline development group received procedural and administrative support from IKNL (Comprehensive Cancer Centre for the Netherlands) and support on methodology from Bureau ME-TA. Partial funding was obtained from SKMS (Quality Funds Foundation of Dutch Medical Specialists). This subsidy would not have been possible without the extensive assistance provided by the NVvR (Radiological Society of the Netherlands).

Declaration of interest

Partial funding for the guideline revision was obtained from the Society of Dutch Medical Specialists in the framework of the SKMS. IKNL sponsored some of the cost. On two occasions, as well as at the beginning and end of the process, all of the members of the guideline development group were asked to fill out a statement of potential conflicts of interest, in which they stated their relationship with the pharmaceutical industry. A list of these statements of interest can be found in the appendices.

Patient involvement

In developing this guideline, four clinical questions were formulated. These questions emerge from an inventory of clinical problems collected in the field from professionals, patients and patient representatives.

 

Also, A multidisciplinary guideline development group was formed in early 2010 to create and implement the revision. This group consisted of mandated representatives from all of the relevant specialisations concerned with breast cancer, plus two delegates from the BVN (Dutch Breast Cancer Society).

 

Method of development

Evidence based

Implementation

Feasibility has been taken into account in developing the guideline. This included attention to factors that could promote or hinder putting the advice into practice. Examples include the implementation of an analysis of problems, the multidisciplinary composition of the guideline development group, and making active use of support from the guideline development group members. Presenting the draft guideline to the field and communicating what, if anything, is being done with the responses, also promotes implementation. In this manner, a guideline has been developed that answers current questions in the field.

The guideline is distributed widely and is available in digital form on the Dutch Guideline Database. The guideline may also be brought to the attention of a wider audience in other periodicals or continuing education sessions, for example. To promote use of the guideline, we recommend that the regional tumour working groups and group practices, as well as scientific and professional organisations, repeatedly bring the guideline to the attention of their members. Any problems that may arise in using the guidelines can then be discussed and, when appropriate, submitted to the national guideline development group, as it is a "living" guideline. If desirable, parts of the guideline can be made more explicit by formulating regional additions or translation to the local situation in departmental and/or hospital protocols.

In principle, indicators are determined during development of the guideline that can be used to monitor implementation of the recommendations. Via a documentation project, these indicators can then be used to determine the extent of compliance with the guideline. The information from the documentation project becomes input for the revision of the guideline.

Methods and proces

This module has been evidence-based revised in 2008 and consensus based updated in 2012.

 

A revision of an existing guideline consists of revised and updated text. Revised text is new text based on an evidence-based review of the medical literature; updated text is the old guideline text which has been edited by the experts without performing a review of medical literature. Each section of the guideline states what type of revision has taken place. Each chapter of the guideline is structured according to a set format, given below. The purpose of this is to make the guideline transparent, so that each user can see on what literature and considerations the recommendations are based on.

 

Description of the literature

To the greatest extent possible, the answers to the fundamental questions (and therefore the recommendations in this guideline) were based on published scientific research. The articles selected were evaluated by an expert in methodology for their research quality, and graded in proportion to evidence using the following classification system:

 

Classification of research results based on level of evidence

A1

Research   on the effects of diagnostics on clinical outcomes in a prospectively   monitored, well-defined patient group, with a predefined policy based on the   test outcomes to be investigated, or decision analysis research into the   effects of diagnostics on clinical outcomes based on results of a study of   A2-level and sufficient consideration is given to the interdependency of   diagnostic tests.

A2

Research   relative to a reference test, where criteria for the test to be investigated   and for a reference test are predefined, with a good description of the test   and the clinical population to be investigated; this must involve a large   enough series of consecutive patients; predefined upper limits must be used,   and the results of the test and the "gold standard" must be   assessed independently. Interdependence is normally a feature of situations   involving multiple diagnostic tests, and their analysis must be adjusted   accordingly, for example using logistic regression.

B

Comparison   with a reference test, description of the test and population researched, but   without the other features mentioned in level A.

C

Non-comparative   trials

D

Opinions   of experts, such as guideline development group members

 

Conclusions

Based on the medical literature, one or more relevant conclusions are made for each section. The most important literature is listed according to the level of evidential strength, allowing conclusions to be drawn based on the level of
evidence. All the medical literature included in the conclusion is described in the bibliography.

 

Classification of conclusions based on literature analysis

1

Based   on 1 systematic review (A1) or at least 2 independent A2 reviews.

2

Based   on at least 2 independent B reviews

3

Based   on 1 level A2 of B research, or any level C research

4

Opinions   of experts, such as guideline development group members

 

Other considerations

Based on the conclusion(s), recommendations are made. However, there are other considerations that contribute to formulation of the recommendation besides literature evidence, such as safety, the patients' preferences, professional expertise, cost-effectiveness, organisational aspects and social consequences. The other considerations are mentioned separately. In this manner, it is clear how the guideline development group arrived at a particular recommendation.

 

Recommendations

The final wording of the recommendation is the result of the scientific conclusion, taking into account the other considerations. The purpose of following this procedure and drawing up the guidelines  in this format is to increase transparency.

 

References

An alphabetical list of literature references can be found at the end of the guideline.

 

All draft texts have been discussed by the guideline development group.

Search strategy

Searches are available upon request. Please contact the Richtlijnendatabase.