Funding for this research was provided by:
Folke Hermansen Foundation (2013, 2014)
Helse Vest Regionalt Helseføretak (911790)
Helse Sør-Øst RHF (2014021)
Dansk Kræftforsknings Fond
Received: 26 September 2019
Accepted: 13 April 2020
First Online: 5 May 2020
Ethics approval and consent to participate
: This study was approved by the Regional Committees for Medical and Health Research Ethics (REC), part of the Norwegian National Research Ethics Committees. The Stavanger cohort was approved by REC Region West, approval number 2010/2014. As this is a retrospective study, approval was given without written consent from the patients. All insights in a patient’s journal were monitored electronically, and all except the treating physician were required to state the reason why they needed to read that patient’s journal. This log was always open for the patient to view. The Oslo2 cohort was approved by REC Region South East, approval number 2016/433 and 429–04148. These patients were included at the time of primary surgery after giving written informed consent.
: Not applicable.
: None of the authors have any financial or other relationships with entities that have investment, licensing, or other commercial interests in the subject matter under consideration in this article.