Breast Cancer Research and Treatment最新文献

{"title":"Interstitial lung disease in metastatic breast cancer: a landscape review using SEER-Medicare.","authors":"Laura C Pinheiro, Anjile An, Chrystal A Landry, Emily Tonorezos, Kerri I Aronson","doi":"10.1007/s10549-026-08043-y","DOIUrl":"10.1007/s10549-026-08043-y","url":null,"abstract":"<p><strong>Introduction: </strong>Interstitial lung disease (ILD) is a serious side effect of certain mBC treatments, but our understanding of its prevalence outside of clinical trials and treatment-specific studies is limited. We sought to characterize the incidence of ILD among a large, population-based cohort of adults with mBC in the United States.</p><p><strong>Methods: </strong>We included females and males aged 66 + years who were diagnosed with Stage IV breast cancer (as their first cancer) between January 1, 2002-December 31, 2017, using the SEER-Medicare linked. Our primary outcome was an incident ILD diagnosis after their mBC diagnosis, which was operationalized as a binary outcome. We examined demographic and clinical factors associated with incident ILD using logistic regression models.</p><p><strong>Results: </strong>Among the 14,343 patients with mBC and no evidence of ILD at baseline, the median age at diagnosis was 76 (IQR 70, 82) years and 98% were female. Overall, 1,806 (12.6%) had an ILD diagnosis after mBC diagnosis. There was no significant difference in proportion of patients who received a pharmacologic treatment that carries the potential risk of ILD between patients who received an ILD diagnosis and those who did not (14% vs. 12%).</p><p><strong>Conclusions: </strong>ILD is prevalent in 12.6% of adults with mBC, yet oncology guidelines for monitoring for this intrusive and potentially fatal complication are sparse and non-specific. Patient education raising awareness of ILD symptoms and engaging primary care and pulmonary medicine in may improve patient outcomes and quality of life.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13457256/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of tumor Schwann cells with epithelial-mesenchymal transition and immune-suppressive microenvironment in triple-negative breast cancer.","authors":"Kei Kawashima, Eslam A Elsaedy, Masanori Oshi, Akimitsu Yamada, Kazutaka Narui, Shipara Gandhi, Elizabeth Repasky, Takashi Ishikawa, Itaru Endo, Kazuaki Takabe","doi":"10.1007/s10549-026-08050-z","DOIUrl":"10.1007/s10549-026-08050-z","url":null,"abstract":"<p><strong>Purpose: </strong>Tumor-associated nerves have recently emerged as an understudied key regulator of cancer biology. However, its quantification using histological or transcriptomic approaches is challenging because their small diameters hinder reliable detection and their cell bodies that hold most mRNA reside outside the tumor. This study evaluated a Schwann cell (SC)-related transcriptomic score as a surrogate for tumor-associated nerves in tumors from triple-negative breast cancer (TNBC) patients.</p><p><strong>Methods: </strong>Transcriptomic and clinical data from three independent TNBC cohorts, TCGA (n = 170), METABRIC (n = 335), and SCAN-B (n = 174) were analyzed. An SC score was calculated from SC-related gene signatures, and spatial transcriptomics was used to validate SC localization. In addition, seven independent neoadjuvant chemotherapy (NAC) cohorts were analyzed to evaluate the association between SC score and treatment response. Associations between the SC score and clinical features, genomic features, proliferation, treatment response, and the tumor microenvironment (TME) were evaluated.</p><p><strong>Results: </strong>SC signature genes spatially localized to intratumoral nerve regions, confirming that the SC score reflects their presence within tumors. SC-high tumors were associated with lower mutation burden and with less cell proliferation in the TCGA, METABRIC, and SCAN-B cohorts. SC-high tumors were also associated with low immune activity and fewer infiltrating immune cells, along with enrichment of epithelial-mesenchymal transition (EMT), TGF-beta signaling and stromal remodeling pathways.</p><p><strong>Conclusions: </strong>The SC score-high TNBC is associated with lower cell proliferation, enhanced stromal remodeling and EMT and suppressed immune activity, suggesting a role of neural-associated TME features in shaping TNBC biology.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13457385/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patient-reported outcomes in clinical trials leading to breast cancer drug approvals: are we making them count?","authors":"Samuel Margolis, Andre Naguib Guirguis, Catherine Lee, Saiya Smith, Alexis LeVee, Marla D Lipsyc-Sharf, Aditya Bardia, Mina S Sedrak","doi":"10.1007/s10549-026-08051-y","DOIUrl":"10.1007/s10549-026-08051-y","url":null,"abstract":"<p><strong>Purpose: </strong>Patient-reported outcomes (PROs) inform benefit-risk tradeoffs in breast cancer treatment, yet reporting quality across registration trials remains incompletely characterized.</p><p><strong>Methods: </strong>We conducted a scoping review of PRO reporting in randomized trials supporting FDA breast cancer drug approvals (January 2011-December 2024), identified via the FDA Oncology Approval Notifications database. Associated manuscripts were retrieved through systematic PubMed and EBSCO searches using trial-specific NCT identifiers. We assessed PRO endpoint prespecification status, instruments used, PRO publication delay (defined as the interval in months between the primary trial manuscript and corresponding PRO-dedicated manuscript publication date), and missing data reporting across eligible primary trial, PRO-dedicated, and subpopulation-specific PRO manuscripts.</p><p><strong>Results: </strong>We identified 34 FDA breast cancer drug approvals supported by 36 unique randomized trials, yielding 45 eligible manuscripts. No trial designated PROs as a primary or co-primary endpoint; nine (25%) did not explicitly prespecify them. Median PRO publication delay was 18 months, with eight trials experiencing a delay of two or more years. Missing data handling methods were described in 33% of manuscripts and reasons for missingness in 11%.</p><p><strong>Conclusion: </strong>In this scoping review, PROs were commonly collected but inconsistently prespecified, often delayed, and incompletely reported. Registration trials should strengthen PRO prespecification, reduce publication delay, and adhere to missing data reporting standards.</p><p><strong>Clinical trial number: </strong>Not applicable.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13457446/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-reported racial and ethnic discrimination in patient-provider interactions and the initiation of adjuvant therapies for breast cancer in the pathways study.","authors":"Kevin R Bitsie, Thomas A Pearson, Marilyn L Kwan, Lusine Yaghjyan, Lisa Scarton, Salma Shariff-Marco, Therese Y Andraos, Lia L D'Addario, Lawrence H Kushi, Ting-Yuan David Cheng","doi":"10.1007/s10549-026-08037-w","DOIUrl":"10.1007/s10549-026-08037-w","url":null,"abstract":"<p><strong>Purpose: </strong>Despite advancements in breast cancer adjuvant therapies, some patients with indications may not receive treatment. We examined the association of self-reported racial/ethnic discrimination in patient-provider interactions and the receipt of clinically indicated therapies.</p><p><strong>Methods: </strong>The Pathways Study is a prospective cohort of women diagnosed with invasive breast cancer from 2005 to 2013 at Kaiser Permanente Northern California. Racial/ethnic discrimination in patient-provider interactions was assessed from the Interpersonal Processes of Care survey at baseline, 6 months, and 24 months post-diagnosis. Logistic regression compared women who did not initiate clinically-indicated adjuvant therapy with those who did overall, and by race and ethnicity. Covariates included race and ethnicity, age at diagnosis, country of birth, education level, income, marital status, and American Joint Committee on Cancer staging.</p><p><strong>Results: </strong>Overall, 3,610 women had indication for hormonal therapy, 2,450 for chemotherapy, and 3,258 for radiation therapy. In multivariable analyses, women reporting discrimination were at increased odds of not initiating hormonal therapy (adjusted odds ratio [aOR] = 1.43, 95% CI = 1.05-1.93) than those who did not self-report discrimination, regardless of their race/ethnicity. An increased odds of non-initiation for reported discrimination was found for radiation therapy (aOR = 1.26, 95% CI = 0.99-1.61), although it was not statistically significant. There was no association for chemotherapy initiation (aOR = 0.96, 95% CI = 0.69-1.33).</p><p><strong>Conclusion: </strong>Self-reported racial/ethnic discrimination in patient-provider interactions was associated with the non-initiation of hormonal therapy in women with breast cancer. Further studies are needed to explore the impact of this association on breast cancer prognosis.</p><p><strong>Clinical trial registration: </strong>Not applicable.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13457354/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Locoregional recurrence and mortality after breast cancer surgery in patients aged 85 and older.","authors":"David Foulad, Jacqueline Tsai, Ingrid Luo, Adele Xu, Mina Satoyoshi, Su-Ying Liang, Pragati Kenkare, Summer Han, Allison W Kurian, Irene L Wapnir","doi":"10.1007/s10549-026-08044-x","DOIUrl":"10.1007/s10549-026-08044-x","url":null,"abstract":"<p><strong>Purpose: </strong>Life expectancy is increasing and the number of patients age ≥ 85 with breast cancer (BC) may be on the rise. We report descriptive statistics regarding surgical management and outcomes in this cohort.</p><p><strong>Methods: </strong>Patients ≥ 85 years surgically treated for a primary or in-breast tumor recurrence (IBTR) were identified through Oncoshare, a database that links Stanford Healthcare and Sutter Health electronic medical records with the California Cancer Registry.</p><p><strong>Results: </strong>From 2010 to 2019, 91 patients, 65 (71%) aged 85-89 and 26 (29%) ≥ 90 + years were identified. 29.2% were screen-detected compared to 57.7% with a prior BC. Lumpectomy was performed in 70% of 96 cancers, nodal staging in 36% of lumpectomies and 91% of mastectomies. Locoregional recurrences (LRR) occurred in 18 patients, 17 after lumpectomy and two BC-related deaths. BC-specific survival was 100.0% at 3 years and 98.0% (95%CI: 94.3%-100.0%) at 5 years. Overall survival (OS) was 77.9% (95% CI: 68.8%-88.1%) at 3 years and 59.9% (95% CI: 49.3%-72.6%) at 5 years. Five-year OS was 71.9% (95% CI: 60.4%-85.6%) for those 85-89 years vs. 28.3% (95% CI: 13.6%-58.6%) for those ≥ 90 years, (p < 0.001). Life expectancy, estimated as median OS, was 7.6 (85-89)and 3.5 (> 90) years. The cumulative incidence of LRR was 4.6%(95% CI: 2.2-9.0%) at 3 years and 13.4%(95% CI: 5.9-20.8%) at 5 years, factoring death as a competing risk using the Aalen-Johansen estimator.</p><p><strong>Conclusion: </strong>Surgery achieves satisfactory local control of disease in patients ≥ 85 years with a new BC or IBTR.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148677003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimising screening intervals and BI-RADS management pathways in ultrasound-based breast cancer screening: real-world evidence from Shenzhen (2018-2023).","authors":"Wanyi Sun, Huan Li, Xuelian Zhao, Shangying Hu, Haifeng Qi, Shuyan Jin, Wenxia Zhang, Fanghui Zhao","doi":"10.1007/s10549-026-08045-w","DOIUrl":"10.1007/s10549-026-08045-w","url":null,"abstract":"<p><strong>Purpose: </strong>To identify screening intervals and BI-RADS-specific management pathways that balance cancer detection yield against recall burden in ultrasound-based breast cancer screening in China.</p><p><strong>Methods: </strong>We analysed 1,694,838 ultrasound examinations reported with BI-RADS (2018-2023). For BI-RADS 1/2, inter-screen intervals were evaluated by recall rate, cancer detection rate (CDR), positive predictive value (PPV), and early-stage proportion. For BI-RADS 0/3/4/5, we assessed associations between biopsy waiting time and PPV/early-stage proportion, and examined imaging follow-up outcomes for BI-RADS 4A.</p><p><strong>Results: </strong>Among 337,497 screening intervals following BI-RADS 1/2, longer intervals were associated with higher CDR (0.13-0.54 per 1,000) but higher recall (17.4%-22.1%) and lower PPV (61.1%-31.0%), while early-stage proportion remained stable. The interval that best balanced yield and downstream burden was 13-24 months for women aged ≥ 40 years and 25-36 months for women aged < 40 years, achieving higher detection yield and PPV without a material increase in recall. Among 1,949 BI-RADS 4/5 biopsies, PPV was low for 4A (12.3%-25.0%), declined markedly with biopsy delay for 4B (60.5% to 25.0%), and remained consistently high for 4C/5 (> 60%/>93%). Among BI-RADS 4A lesions 64.7% (10,909/16,871) showed imaging downgrading during follow-up. In 487 BI-RADS 3 cases undergoing biopsy, delayed biopsy increased PPV without changing early-stage proportion.</p><p><strong>Conclusion: </strong>A 2-year screening interval is recommended for women aged 40-64 years, extendable to 3 years for those aged < 40. Prompt biopsy is warranted for BI-RADS 4B/4C/5. The high image downgrade rate of BI-RADS 4A suggests overestimation and supports imaging-based triage, requiring further validation. Imaging surveillance is preferable for BI-RADS 3 lesions.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13447344/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148677085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Invasive lobular breast cancer in young patients without adjuvant systemic treatment: 15-year survival outcomes.","authors":"R A B Voorthuis, M Opdam, N D Ter Hoeve, M da Silva, M Christgen, G Dackus, P V Diest, P W B Derksen, F S Hilbers, S C Linn","doi":"10.1007/s10549-026-08024-1","DOIUrl":"10.1007/s10549-026-08024-1","url":null,"abstract":"<p><strong>Purpose: </strong>Invasive lobular carcinoma (ILC) of the breast typically affects older women. As a result, there is limited research on prognosis and prognostic factors in young women with ILC. Here we set out to determine the long-term outcome and prognostic factors of women under 40 years of age with lymph node-negative (N0), hormone-receptor positive (HR+)/human epidermal growth-factor receptor 2 negative (HER2-) ILC who did not receive adjuvant systemic treatment (chemo- and/or endocrine therapy).</p><p><strong>Methods: </strong>Through the Netherlands Cancer Registry we selected all systemically untreated patients younger than 40 years with HR+/HER2-, N0, early breast cancer diagnosed in the Netherlands from 1989-2000. At the time, node-negativity was considered a favorable prognostic marker and guidelines recommended no adjuvant systemic therapy for this subgroup. Distant recurrence-free survival (DRFS), recurrence-free survival (RFS) and overall survival (OS) were assessed according to the STEEP criteria. Uni- and multivariable Cox proportional hazard models were used to assess prognosis, calculating hazard ratios (HR) with confidence interval (CI).</p><p><strong>Results: </strong>Of the n = 1138 selected patients, n = 95 were histologically classified as ILC and n = 805 as invasive breast cancer of no special type (BC-NST), n = 238 were classified as other breast cancer subtype. In ILC, tumor grade was not associated with DRFS/RFS or OS (HR for DRFS 1.40, 95%CI 0.42-4.63). However, the presence of lymphovascular invasion (LVI) (adjusted HR DRFS 2.81, 95%CI 1.14-6.94, p < 0.05) and multifocality (adjusted HR DRFS 3.28, 95%CI 1.49-7.22, p < 0.01) were. When comparing DRFS, RFS and OS in matched low-risk luminal A-like ILC vs. BC-NST, we observed a trend for worse 15-year survival in ILC (15-year DRFS 63% in ILC vs. 74% in BC-NST; HR 1.50, 95%CI 0.98-2.29, p = 0.06).</p><p><strong>Conclusion: </strong>In these young patients with systemically untreated N0 ILC we show that grade was not prognostic at 15 years follow-up, whereas LVI and multifocality were. Furthermore, ILC had a numerically worse 15-year survival than matched luminal A-like BC-NST.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13447550/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148676995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First-line treatment patterns and real-world survival outcomes in PD-L1-negative locally recurrent inoperable or metastatic triple-negative breast cancer in the United States.","authors":"Tiffany A Traina, Elizabeth Serra, Jerome Bedard, Mohira Levesque-Leroux, Patrick Gagnon-Sanschagrin, Annie Guérin, Silke Guenther, George Joseph, Victoria Guan, Jonathan Salcedo","doi":"10.1007/s10549-026-08040-1","DOIUrl":"10.1007/s10549-026-08040-1","url":null,"abstract":"<p><strong>Purpose: </strong>Contemporary real-world data on treatment patterns and clinical outcomes in patients with programmed death ligand 1 (PD-L1)-negative locally recurrent inoperable or metastatic triple-negative breast cancer (lr/mTNBC) are sparse. We describe first-line (1L) systemic therapies and real-world survival outcomes in this population in the United States (US).</p><p><strong>Methods: </strong>Adults with PD-L1-negative lr/mTNBC initiating 1L systemic treatment in the US were identified using the Komodo Research Data (KRD+; 1/1/2016-12/31/2023). Treatment patterns, including treatment durations and sequences from 1L through three lines of therapy, real-world overall survival (rwOS) and progression-free survival (rwPFS) from 1L, were analyzed. rwOS and rwPFS were summarized using Kaplan-Meier methods in subgroups of patients with ≥ 18 months and ≥ 6 months of potential follow-up, respectively.</p><p><strong>Results: </strong>Overall, 929 patients were included (median age 59.0 years, 60.1% White, 26.4% Black or African American, 64.9% commercially insured). Most common 1L treatments included cyclophosphamide + doxorubicin-based regimens (28.1%), capecitabine (12.7%), and paclitaxel (10.4%); 44.5% were observed to receive a second-line treatment, and 16.0% a third-line treatment. Treatment sequences were heterogeneous, with 329 unique sequences captured. Median rwOS and rwPFS (95% confidence interval) were 12.2 (10.7, 14.4) months and 4.7 (4.5, 5.2) months, respectively.</p><p><strong>Conclusion: </strong>In this large real-world US cohort of patients with PD-L1-negative lr/mTNBC, 1L treatment regimens were highly heterogeneous and often diverged from guideline recommendations. Despite treatment, survival outcomes remain poor within this patient population. These findings highlight the need for more effective therapeutic options for this population.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13442314/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148676970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodological considerations on the predictive value of tumor-infiltrating lymphocytes for pathological complete response in early triple-negative breast cancer.","authors":"Malaha Ali","doi":"10.1007/s10549-026-08048-7","DOIUrl":"10.1007/s10549-026-08048-7","url":null,"abstract":"","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148668362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Birth cohort differences in reproductive and lifestyle breast cancer risk factors among women in the Nigerian breast cancer study.","authors":"Gideon T Dosunmu, Olasubomi Omoleye, Dezheng Huo, Mihai Giurcanu, Yonglan Zheng, Toshio F Yoshimatsu, Olufunmilayo I Olopade","doi":"10.1007/s10549-026-08046-9","DOIUrl":"10.1007/s10549-026-08046-9","url":null,"abstract":"<p><strong>Background: </strong>Breast cancer (BC) is the leading cause of cancer in women worldwide with rising incidence in low- and middle-income countries (LMIC). We examined trends in reproductive and lifestyle factors for breast cancer across birth cohorts of Nigerian women.</p><p><strong>Methods: </strong>We conducted a cross-sectional analysis of 2,309 female control participants (mean age, 42.5 ± 13.0 years) recruited between 1998 and 2017 as part of the Nigerian Breast Cancer Study (NBCS), an ongoing case-control study. Birth cohort was modeled as an ordinal predictor to evaluate temporal trends. Reproductive and lifestyle factors were analyzed across six birth cohorts (< 1940, 1940-1949, 1950-1959, 1960-1969, 1970-1979, and ≥ 1980). Analyses of reproductive variables were repeated among women aged ≥ 40 years, and hormonal contraceptive use was additionally evaluated among women aged ≥ 30 years.</p><p><strong>Results: </strong>Among all women, mean age at menarche declined from 16.0 years among women born before 1940 to 15.1 years among those born in or after 1980 (P for trend = 0.001), whereas age at thelarche remained stable across birth cohorts. Among women aged ≥ 40 years, mean parity declined from 6.1 to 4.1 live births, and cumulative lifetime breastfeeding duration decreased from 114 to 75 months (both P for trend < 0.001). Mean breastfeeding duration per live birth showed only a modest decline. Among women aged ≥ 30 years, the prevalence of ever hormonal contraceptive use increased from 7.2% to 55.8% across birth cohorts (P for trend < 0.001). Among all women, alcohol consumption remained low throughout (≤ 9% in every birth cohort).</p><p><strong>Conclusions: </strong>Modest generational changes were observed in several reproductive and lifestyle factors traditionally associated with breast cancer risk among Nigerian women. These findings describe temporal changes in breast cancer risk factor profiles across successive birth cohorts. Future studies should examine environmental and other contextual exposures that may contribute to the evolving epidemiology of breast cancer in Nigeria and other low- and middle-income countries.</p>","PeriodicalId":9133,"journal":{"name":"Breast Cancer Research and Treatment","volume":"218 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13667898/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148668390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}