Contralateral breast cancer risk in patients with breast cancer and a germline-BRCA1/2 pathogenic variant undergoing radiation.

Background: Radiation-induced secondary breast cancer (BC) may be a concern after radiation therapy (RT) for primary breast cancer (PBC), especially in young patients with germline (g)BRCA-associated BC who already have high contralateral BC (CBC) risk and potentially increased genetic susceptibility to radiation. We sought to investigate whether adjuvant RT for PBC increases the risk of CBC in patients with gBRCA1/2-associated BC.

Methods: The gBRCA1/2 pathogenic variant carriers diagnosed with PBC were selected from the prospective International BRCA1/2 Carrier Cohort Study.

Risk of metachronous contralateral breast cancer in patients with primary invasive lobular breast cancer: Results from a nationwide cohort.

Lobular primary breast cancer (PBC) histology has been proposed as a risk factor for contralateral breast cancer (CBC), but results have been inconsistent. We investigated CBC risk and the impact of systemic therapy in lobular versus ductal PBC. Further, CBC characteristics following these histologic subtypes were explored.

Effects of chemotherapy on contralateral breast cancer risk in BRCA1 and BRCA2 mutation carriers: A nationwide cohort study.

Aim: BRCA1/2 mutation carriers with primary breast cancer (PBC) are at high risk of contralateral breast cancer (CBC). In a nationwide cohort, we investigated the effects of chemotherapeutic agents given for PBC on CBC risk separately in BRCA1 and BRCA2 mutation carriers.

Patients And Methods: BRCA1 or BRCA2 mutation carriers with an invasive PBC diagnosis from 1990 to 2017 were selected from a Dutch cohort.

Prediction of contralateral breast cancer: external validation of risk calculators in 20 international cohorts.

Background: Three tools are currently available to predict the risk of contralateral breast cancer (CBC). We aimed to compare the performance of the Manchester formula, CBCrisk, and PredictCBC in patients with invasive breast cancer (BC).

Methods: We analyzed data of 132,756 patients (4682 CBC) from 20 international studies with a median follow-up of 8.

The impact of lifestyle and reproductive factors on the risk of a second new primary cancer in the contralateral breast: a systematic review and meta-analysis.

Purpose: The risk of being diagnosed with contralateral breast cancer (CBC) is an important health issue among breast cancer survivors. There is an increasing interest in the effect of lifestyle and reproductive factors on CBC risk, since these factors may partly be modifiable. We performed a systematic review and meta-analysis and aimed to evaluate the impact of lifestyle and reproductive factors on CBC risk in population-based breast cancer studies.

Prediction and clinical utility of a contralateral breast cancer risk model.

Background: Breast cancer survivors are at risk for contralateral breast cancer (CBC), with the consequent burden of further treatment and potentially less favorable prognosis. We aimed to develop and validate a CBC risk prediction model and evaluate its applicability for clinical decision-making.

Methods: We included data of 132,756 invasive non-metastatic breast cancer patients from 20 studies with 4682 CBC events and a median follow-up of 8.

Risk factors for metachronous contralateral breast cancer: A systematic review and meta-analysis.

Background: The risk of developing metachronous contralateral breast cancer (CBC) is a recurrent topic at the outpatient clinic. We aimed to provide CBC risk estimates of published patient, pathological, and primary breast cancer (PBC) treatment-related factors.

Methods: PubMed was searched for publications on factors associated with CBC risk.

Adjuvant radiotherapy for primary breast cancer in BRCA1 and BRCA2 mutation carriers and risk of contralateral breast cancer with special attention to patients irradiated at younger age.

The purpose of this study was to estimate the influence of adjuvant radiotherapy for primary breast cancer (BC) on the risk of contralateral BC (CBC) in BRCA1 or BRCA2 (BRCA1/2) mutation carriers, with special attention to patients irradiated at age younger than 40 years. Additionally, tendencies in locoregional treatments and rates of contralateral risk-reducing mastectomy over time were explored. In this retrospective cohort study, 691 BRCA1/2-associated BC patients treated between 1980 and 2013 were followed from diagnosis until CBC or censoring event including ipsilateral BC recurrence, distant metastasis, contralateral risk-reducing mastectomy, other invasive cancer diagnosis, death, or loss to follow up.