Invasive recurrence after breast conserving treatment of ductal carcinoma in situ of the breast in the Netherlands: time trends and the association with tumour grade.

Background: The first aim of this study was to examine trends in the risk of ipsilateral invasive breast cancer (iIBC) after breast-conserving surgery (BCS) of ductal carcinoma in situ (DCIS). A second aim was to analyse the association between DCIS grade and the risk of iIBC following BCS.

Patients And Methods: In this population-based, retrospective cohort study, the Netherlands Cancer Registry collected information on 25,719 women with DCIS diagnosed in the period 1989-2021 who underwent BCS.

Long-term trends in incidence, characteristics and prognosis of screen-detected and interval cancers in women participating in the Dutch breast cancer screening programme.

Background: No studies are available in which changes over time in characteristics and prognosis of patients with interval breast cancers (ICs) and screen-detected breast cancers (SDCs) have been compared. The aim was to study these trends between 1995 and 2018.

Methods: All women with invasive SDCs (N = 4290) and ICs (N = 1352), diagnosed in a southern mammography screening region in the Netherlands, were included and followed until date of death or 31 December 2022.

Non-visualized sentinel nodes in breast cancer patients; prevalence, risk factors, and prognosis.

Background: Evidence and consensus is lacking in international guidelines regarding axillary treatment recommendations for patients in whom a sentinel lymph node (SLN) cannot be visualized (non-vSLN) during the sentinel node procedure. In this study we aimed to determine the prevalence of non-vSLNs in a Dutch population of breast cancer patients and to examine predictors and survival rate for non-vSLN.

Methods: A nationwide, retrospective, population-based study was performed including 116,920 patients with invasive breast cancer who underwent a SLN procedure in the Netherlands between January 2005 and December 2013.

Estrogen and progesterone receptor expression levels do not differ between lobular and ductal carcinoma in patients with hormone receptor-positive tumors.

Background: Differences in estrogen (ER) and progesterone (PR) expression between invasive lobular carcinoma (ILC) and invasive ductal carcinoma (IDC) could be an underlying reason for the difference in chemo-sensitivity and response to hormonal therapy between ILC and IDC. The aim of this study was to investigate the differences in ER and PR expression levels between postmenopausal patients with hormonal receptor-positive ILC and IDC.

Methods: We included all ER and/or PR receptor-positive ILC and IDC, diagnosed between January 2011 and December 2013 from the population-based Netherlands Cancer Registry.

The impact of mammography screening on breast cancer incidence.

Evaluation of: Bleyer A, Welch HG. Effect of three decades of screening mammography on breast-cancer incidence. N.