Research question:

The aim of this investigation is to

– present and assess any correlation between the volume of services (VoS) and the quality of the treatment outcome in the surgical treatment of primary mammary carcinoma (research question 1) and

– present studies which investigate the effects of a minimum number of cases introduced into the healthcare system on the quality of the treatment outcome in the surgical treatment of primary mammary carcinoma (research question 2).

If this process reveals data on a correlation between VoS and quality of treatment outcome in palliative surgery, they will be presented as supplementary information.

Conclusion:

For the investigation of any correlation between VoS and treatment quality in the surgical treatment of breast cancer, a total of 10 studies were included. One of the 10 included studies was assessed as having a high informative value of results.

For the outcome of all-cause mortality, based on a high informative value of results, a correlation between both hospital and doctor VoS and treatment quality was derived. Hence, a higher VoS is associated with lower mortality rates. For other mortality outcomes (breast cancer mortality and other-cause mortality), based on a low informative value of results, a correlation was found either only on the hospital level or only on the doctor level. Again, the results showed lower mortality for these levels.

With respect to performing a reoperation, based on a low informative value of results, it was possible to derive a correlation between both doctor and hospital VoS and treatment quality. At the hospital level, a correlation between VoS and treatment quality was apparent even in comparison with the intermediate VoS category. The results show lower reoperation rates in higher VoS categories.

No studies of meaningful interpretive value were found which investigated any correlation between VoS and treatment quality reflected by other outcomes, such as adverse effects of therapy, local recurrence, disease-free survival, or health-related quality of life. Further, it was not possible to include studies of meaningful interpretive value investigating any effects of specifically introduced minimum case numbers.

Publisher

Institute for Quality and Efficiency in Health Care

Topic

Relationship between volume of services and quality of treatment outcome in the surgical treatment of breast cancer - rapid report

Commissioning agency

Federal Joint Committee

Commission awarded on

20 December 2018

Internal Commission No.

V18-05

Address of publisher

This report was prepared in collaboration with external experts.

The responsibility for the contents of the report lies solely with IQWiG.

According to §139b (3) No. 2 of Social Code Book (SGB) V, Statutory Health Insurance, external experts who are involved in the Institute’s research commissions must disclose “all connections to interest groups and contract organizations, particularly in the pharmaceutical and medical devices industries, including details on the type and amount of any remuneration received”. The Institute received the completed Form for disclosure of potential conflicts of interest from each external expert. The information provided was reviewed by a Committee of the Institute specifically established to assess conflicts of interests. The information on conflicts of interest provided by the external experts and external reviewers is presented in Chapter C of the full report. No conflicts of interest were detected that could endanger professional independence with regard to the work on the present commission.

External expert

• Elmar Stickeler, Clinic for Gynaecology and Obstetrics, University Hospital Aachen, Germany

External review of the rapid report

• Bernd Gerber, University Women's Clinic and Polyclinic at the Südstadt Hospital of the Hanseatic City of Rostock, Germany

IQWiG thanks the external experts for their collaboration in the project.

IQWiG employees

• Franziska Vosseberg
• Eva Höfer
• Lutz Altenhofen
• Ralf Bender
• Mandy Kromp
• Matthias Maiworm
• Claudia Mischke
• Dorothea Sow