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result(s) for
"Chappuis, Pierre O"
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Machine learning techniques for personalized breast cancer risk prediction: comparison with the BCRAT and BOADICEA models
2019
Background
Comprehensive breast cancer risk prediction models enable identifying and targeting women at high-risk, while reducing interventions in those at low-risk. Breast cancer risk prediction models used in clinical practice have low discriminatory accuracy (0.53–0.64). Machine learning (ML) offers an alternative approach to standard prediction modeling that may address current limitations and improve accuracy of those tools. The purpose of this study was to compare the discriminatory accuracy of ML-based estimates against a pair of established methods—the Breast Cancer Risk Assessment Tool (BCRAT) and Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) models.
Methods
We quantified and compared the performance of eight different ML methods to the performance of BCRAT and BOADICEA using eight simulated datasets and two retrospective samples: a random population-based sample of U.S. breast cancer patients and their cancer-free female relatives (
N
= 1143), and a clinical sample of Swiss breast cancer patients and cancer-free women seeking genetic evaluation and/or testing (
N
= 2481).
Results
Predictive accuracy (AU-ROC curve) reached 88.28% using ML-Adaptive Boosting and 88.89% using ML-random forest versus 62.40% with BCRAT for the U.S. population-based sample. Predictive accuracy reached 90.17% using ML-adaptive boosting and 89.32% using ML-Markov chain Monte Carlo generalized linear mixed model versus 59.31% with BOADICEA for the Swiss clinic-based sample.
Conclusions
There was a striking improvement in the accuracy of classification of women with and without breast cancer achieved with ML algorithms compared to the state-of-the-art model-based approaches. High-accuracy prediction techniques are important in personalized medicine because they facilitate stratification of prevention strategies and individualized clinical management.
Journal Article
Clinical outcome of breast cancer in carriers of BRCA1 and BRCA2 mutations according to molecular subtypes
by
Labidi-Galy, S.Intidhar
,
Peron, Julien
,
Bodmer, Alexandre
in
38/23
,
692/4028/67/1347
,
692/4028/67/68
2020
BRCA1/BRCA2
genes play a central role in DNA repair and their mutations increase sensitivity to DNA-damaging agents. There are conflicting data regarding the prognostic value of
BRCA
germline mutations in breast cancer (BC) patients. We collected clinical, pathological and genetic data of a cohort 925 BC patients preselected for genetic screening and treated with neoadjuvant or adjuvant chemotherapy, of whom 266 were
BRCA
carriers. Overall, 171 women carried a
BRCA1
mutation, 95 carried a
BRCA2
mutation, and 659 were non-carriers. In the entire cohort, there was a prolonged disease-free survival (DFS) for
BRCA
carriers (hazard ratio (HR) = 0.63; 95% confidence interval (CI), 0.44–0.90 for
BRCA1;
HR = 0.72; 95%CI, 0.47–1.1 for
BRCA2
;
p
= 0.020) and a trend toward prolonged disease-specific survival (DSS; HR = 0.65; 95%CI, 0.40–1.1 for
BRCA1
; HR = 0.78; 95%CI, 0.44–1.38 for
BRCA2
;
p
= 0.19) though not statistically significant. In the TNBC group,
BRCA
carriers had prolonged DFS (adjusted HR = 0.50; 95%CI, 0.28–0.89
for BRCA1;
adjusted HR = 0.37; 95%CI, 0.11–1.25,
for BRCA2; p
= 0.034) and DSS (adjusted HR = 0.42; 95%CI, 0.21–0.82 for
BRCA1;
adjusted HR = 0.45; 95%CI, 0.11–1.9 for
BRCA2; p
= 0.023). In the non-TNBC group, the
BRCA1
or
BRCA2
mutations did not have any impact on survival. These results suggest that
BRCA1/BRCA2
germline mutations are associated with prolonged survival only if women were diagnosed with TNBC.
Journal Article
Physicians communicating with women at genetic risk of breast and ovarian cancer: Are we in the middle of the ford between contradictory messages and unshared decision making?
by
Fadda, Marta
,
Katapodi, Maria C.
,
Monnerat, Christian
in
Adult
,
Biology and Life Sciences
,
BRCA1 protein
2020
BRCA1/2 genetic testing offers tremendous opportunities for prevention, diagnosis and treatment of breast and ovarian cancer. Women acquire valuable information that can help them to make informed decisions about their health. However, knowing one's susceptibility to developing cancer may be burdensome for several women, as this risk needs to be managed over time through a continuous dialogue with multiple healthcare professionals. We explored how communication between physicians and unaffected women carrying BRCA1/2 germline pathogenic variants was experienced by women in relation to their genetic risk. Data came from qualitative interviews conducted in Switzerland with 32 unaffected women carrying BRCA1/2 pathogenic variants and aware of their genetic status for at least 3 years. We identified three different types of message as conveyed by physicians to women: (1) a normative message, (2) an over-empowering message, and (3) a minimizing message. On one hand, we found that women are exposed to contradictory messages, often simultaneously, in their interactions with healthcare professionals during their post-genetic testing journey. On the other hand, women's reports highlighted the absence of shared decision-making in such interactions. The combination of these two findings resulted in a strong sense of disorientation, frustration, and powerlessness among participants. Healthcare professionals interacting with high cancer risk women are urged to align in favor of a both concerted and shared decision-making approach when discussing options for managing genetic risk.
Journal Article
Letter to the editor: Response to Giardiello D, Antoniou AC, Mariani L, Easton DF, Steyerberg EW
by
Probst-Hensch, Nicole
,
Katapodi, Maria C.
,
Viassolo, Valeria
in
Biomedical and Life Sciences
,
Biomedicine
,
Breast cancer
2020
The interpretation and usefulness of these estimates for each risk factor is limited without reference values from BCRAT/BOADICEA. [...]better/worse calibration does not lead to better/worse class-based or probability-based predictions [6]. Wang X, Huang Y, Li L, Dai H, Song F, Chen K. Assessment of performance of the Gail model for predicting breast cancer risk: a systematic review and meta-analysis with trial sequential analysis. Internal validation of predictive models: efficiency of some procedures for logistic regression analysis.
Journal Article
Risk of first recurrence after treatment in a population-based cohort of young women with breast cancer
2024
Purpose
Breast cancer (BC) in women under 45 is rare yet often aggressive. We aim to analyze loco-regional recurrences (LR), distant recurrences (DR), second breast cancers, and mortality in young BC patients.
Methods
We enrolled 776 women with non-metastatic BC ≤45 years diagnosed from 1970 to 2012. Variables included age, family history, tumor stage/grade, and treatment. We used multivariate Cox regression and competing risk models.
Results
Among the participants, 37.0% were diagnosed before the age of 40. Most had stage I or II, grade II, ER- and PR-positive, HER2-negative tumors. Over a median follow-up of 8.7 years, 10.1% experienced LR, 13.7% developed DR, and 10.8% died, primarily due to BC. The majority of recurrences occurred within the first five years. Older age (>40) significantly reduced the risk of LR and DR. Advanced disease stage, certain surgical strategies, and positive margins increased DR risk. In the cohort diagnosed between 2001 and 2012, recent diagnosis, triple-negative cancer, and hormonal therapy were associated with reduced LR risk. Breast-conserving surgery appeared to offer protective effects against DR.
Conclusion
This study highlights that BC in young women carries a significant risk of early recurrence, with age, tumor characteristics, and treatment modalities influencing outcomes. The findings emphasize the need for tailored treatment strategies for young BC patients, focusing on surgical precision and aggressive adjuvant therapy for high-risk cases. This research contributes valuable insights into managing BC in younger patients, aiding in improving long-term outcomes.
Journal Article
A new bioinformatics tool to help assess the significance of BRCA1 variants
2018
Background
Germline pathogenic variants in the breast cancer type 1 susceptibility gene
BRCA1
are associated with a 60% lifetime risk for breast and ovarian cancer. This overall risk estimate is for all
BRCA1
variants; obviously, not all variants confer the same risk of developing a disease. In cancer patients, loss of BRCA1 function in tumor tissue has been associated with an increased sensitivity to platinum agents and to poly-(ADP-ribose) polymerase (PARP) inhibitors. For clinical management of both at-risk individuals and cancer patients, it would be important that each identified genetic variant be associated with clinical significance. Unfortunately for the vast majority of variants, the clinical impact is unknown. The availability of results from studies assessing the impact of variants on protein function may provide insight of crucial importance.
Results and conclusion
We have collected, curated, and structured the molecular and cellular phenotypic impact of 3654 distinct
BRCA1
variants. The data was modeled in triple format, using the variant as a subject, the studied function as the object, and a predicate describing the relation between the two. Each annotation is supported by a fully traceable evidence. The data was captured using standard ontologies to ensure consistency, and enhance searchability and interoperability. We have assessed the extent to which functional defects at the molecular and cellular levels correlate with the clinical interpretation of variants by ClinVar submitters. Approximately 30% of the ClinVar
BRCA1
missense variants have some molecular or cellular assay available in the literature. Pathogenic variants (as assigned by ClinVar) have at least some significant functional defect in 94% of testable cases. For benign variants, 77% of ClinVar benign variants, for which neXtProt Cancer variant portal has data, shows either no or mild experimental functional defects. While this does not provide evidence for clinical interpretation of variants, it may provide some guidance for variants of unknown significance, in the absence of more reliable data.
The neXtProt Cancer variant portal (
https://www.nextprot.org/portals/breast-cancer
) contains over 6300 observations at the molecular and/or cellular level for BRCA1 variants.
Journal Article
Machine learning-based lifetime breast cancer risk reclassification compared with the BOADICEA model: impact on screening recommendations
by
Probst-Hensch, Nicole
,
Katapodi, Maria C.
,
Viassolo, Valeria
in
692/4028/67/2322
,
692/700/478/2772
,
Adult
2020
Background
The clinical utility of machine-learning (ML) algorithms for breast cancer risk prediction and screening practices is unknown. We compared classification of lifetime breast cancer risk based on ML and the BOADICEA model. We explored the differences in risk classification and their clinical impact on screening practices.
Methods
We used three different ML algorithms and the BOADICEA model to estimate lifetime breast cancer risk in a sample of 112,587 individuals from 2481 families from the Oncogenetic Unit, Geneva University Hospitals. Performance of algorithms was evaluated using the area under the receiver operating characteristic (AU-ROC) curve. Risk reclassification was compared for 36,146 breast cancer-free women of ages 20–80. The impact on recommendations for mammography surveillance was based on the Swiss Surveillance Protocol.
Results
The predictive accuracy of ML-based algorithms (0.843 ≤ AU-ROC ≤ 0.889) was superior to BOADICEA (AU-ROC = 0.639) and reclassified 35.3% of women in different risk categories. The largest reclassification (20.8%) was observed in women characterised as ‘near population’ risk by BOADICEA. Reclassification had the largest impact on screening practices of women younger than 50.
Conclusion
ML-based reclassification of lifetime breast cancer risk occurred in approximately one in three women. Reclassification is important for younger women because it impacts clinical decision- making for the initiation of screening.
Journal Article
Challenges and Opportunities for Cancer Predisposition Cascade Screening for Hereditary Breast and Ovarian Cancer and Lynch Syndrome in Switzerland
by
Monnerat, Christian
,
Heinzelmann-Schwarz, Viola
,
Nikolaidis, Christos
in
Breast Neoplasms - genetics
,
Carcinoma, Ovarian Epithelial
,
Colorectal Neoplasms, Hereditary Nonpolyposis - genetics
2018
Background: An international workshop on cancer predisposition cascade genetic screening for hereditary breast and ovarian cancer (HBOC) and Lynch syndrome (LS) took place in Switzerland, with leading researchers and clinicians in cascade screening and hereditary cancer from different disciplines. The purpose of the workshop was to enhance the implementation of cascade genetic screening in Switzerland. Participants discussed the challenges and opportunities associated with cascade screening for HBOC and LS in Switzerland (CASCADE study); family implications and the need for family-based interventions; the need to evaluate the cost-effectiveness of cascade genetic screening; and interprofessional collaboration needed to lead this initiative. Methods: The workshop aims were achieved through exchange of data and experiences from successful cascade screening programs in the Netherlands, Australia, and the state of Ohio, USA; Swiss-based studies and scientific experience that support cancer cascade screening in Switzerland; programs of research in psychosocial oncology and family-based studies; data from previous cost-effectiveness analyses of cascade genetic screening in the Netherlands and in Australia; and organizational experience from a large interprofessional collaborative. Scientific presentations were recorded and discussions were synthesized to present the workshop findings. Results: The key elements of successful implementation of cascade genetic screening are a supportive network of stakeholders and connection to complementary initiatives; sample size and recruitment of relatives; centralized organization of services; data-based cost-effectiveness analyses; transparent organization of the initiative; and continuous funding. Conclusions: This paper describes the processes and key findings of an international workshop on cancer predisposition cascade screening, which will guide the CASCADE study in Switzerland.
Journal Article
BRCA1/BRCA2 germline mutations and chemotherapy-related hematological toxicity in breast cancer patients
by
Tredan, Olivier
,
Gauchat-Bouchardy, Isabelle
,
Peron, Julien
in
BRCA1 protein
,
BRCA2 protein
,
Breast cancer
2019
PurposeBRCA1 and BRCA2 proteins are central to DNA repair process through homologous recombination. We hypothesize that BRCA1/BRCA2 mutation carriers may exhibit increased hematological toxicity when receiving genotoxic chemotherapy.MethodsWe included women with primary breast cancers screened for BRCA1/BRCA2 germline mutations and treated with (neo)adjuvant chemotherapy in Geneva (Swiss cohort). The primary endpoint was the incidence of febrile neutropenia following the first chemotherapy cycle (C1). Secondary endpoints were the incidence of grade 3–4 neutropenia, grade 4 neutropenia and hospitalization during C1, G-CSF use and chemotherapy dose reduction during the entire chemotherapy regimen. Long-term toxicities (hematological, cardiac and neuropathy) were assessed in the Swiss cohort and a second cohort of patients from Lyon (French cohort).ResultsOverall, 221 patients were assessed for acute hematological toxicity, including 23 BRCA1 and 22 BRCA2 carriers. Following the C1, febrile neutropenia had an incidence of 35% (p = 0.002), 14% (p = 0.562) and 10% among BRCA1, BRCA2 and non-carriers, respectively. Grade 4 neutropenia was found in 57% of BRCA1 (p < 0.001), 14% of BRCA2 (p = 0.861) and 18% of non-carriers. G-CSF support was necessary in 86% of BRCA1 (p = 0.005), 64% of BRCA2 (p = 0.285) and 51% of non-carriers. For long-term toxicity analysis, 898 patients were included (167 BRCA1-, 91 BRCA2- and 640 non-carriers). There was no difference between the 3 groups.ConclusionsBRCA1 germline mutations is associated with greater acute hematological toxicity in breast cancer patients. These observations could have implication for primary prophylaxis with G-CSF.
Journal Article
Hematologic toxicities of chemotherapy in breast and ovarian cancer patients carrying BRCA1/BRCA2 germline pathogenic variants. A single center experience and review of the literature
by
Hu-Heimgartner, Ketty
,
Vazquez, Carla
,
Vuilleumier, Aurélie
in
BRCA1 protein
,
BRCA2 protein
,
Breast
2023
BRCA1 and BRCA2 play a central role in DNA repair and their germline pathogenic variants (gBRCA) confer a high risk for developing breast and ovarian cancer. Standard chemotherapy regimens for these cancers include DNA-damaging agents. We hypothesized that gBRCA carriers might be at higher risk of developing chemotherapy-related hematologic toxicity and therapy-related myeloid neoplasms (t-MN). We conducted a retrospective study of women newly diagnosed with invasive breast or ovarian cancer who were screened for gBRCA1/gBRCA2 at Geneva University Hospitals. All patients were treated with (neo-)adjuvant chemotherapy. We evaluated acute hematologic toxicities by analyzing the occurrence of febrile neutropenia and severe neutropenia (grade 4) at day 7–14 of the first cycle of chemotherapy and G-CSF use during the entire chemotherapy regimen. Characteristics of t-MN were collected. We reviewed medical records from 447 patients: 58 gBRCA1 and 40 gBRCA2 carriers and 349 non-carriers. gBRCA1 carriers were at higher risk of developing severe neutropenia (32% vs. 14.5%, p = 0.007; OR = 3.3, 95% CI [1.6-7], p = 0.001) and of requiring G-CSF for secondary prophylaxis (58.3% vs. 38.2%, p = 0.011; OR = 2.5, 95% CI [1.4–4.8], p = 0.004). gBRCA2 carriers did not show increased acute hematologic toxicities. t-MN were observed in 2 patients (1 gBRCA1 and one non-carrier). Our results suggested an increased acute hematologic toxicity upon exposure to chemotherapy for breast and ovarian cancer among gBRCA1 but not gBRCA2 carriers. A deeper characterization of t-MN is warranted with the recent development of PARP inhibitors in frontline therapy in gBRCA breast and ovarian cancer.
Journal Article