{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:57:26Z","timestamp":1760144246142,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,2]],"date-time":"2024-04-02T00:00:00Z","timestamp":1712016000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>Introduction: Bilateral breast cancers (BBC) diagnosed at an interval apart are uncommon. While metastatic staging guidelines are established in patients with unilateral breast cancer, its role in BBC diagnosed at an interval apart is unclear. We aim to identify the subgroup who would benefit from metastatic staging at contralateral cancer diagnosis. Methods: Eligible patients were divided into three categories: (A) ipsilateral invasive cancer and contralateral ductal carcinoma in situ (DCIS), (B) bilateral invasive cancers and (C) ipsilateral DCIS and contralateral invasive cancer and reviewed retrospectively. We excluded patients with bilateral DCIS, synchronous BBC diagnosed within 6 months from first cancer, patients who were stage IV at first cancer diagnosis and patients with recurrence prior to contralateral cancer. Results: Of 4516 newly diagnosed breast cancer patients, 79 patients were included. Systemic metastasis occurred in 15.6% of patients in Group B. Having nodal positivity of either cancer which were diagnosed \u226430 months apart and nodal positivity of only the contralateral cancer when diagnosed &gt;30 months apart was significantly associated with systemic metastasis (p = 0.0322). Conclusions: Both the nodal status and a 30 months cut-off time interval between the two cancers can be used to identify patients who will benefit from metastatic staging. This finding requires validation in larger studies.<\/jats:p>","DOI":"10.3390\/curroncol31040145","type":"journal-article","created":{"date-parts":[[2024,4,3]],"date-time":"2024-04-03T03:37:21Z","timestamp":1712115441000},"page":"1936-1946","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Determining the Need for Metastatic Staging in Patients with Bilateral Breast Cancers"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1514-6841","authenticated-orcid":false,"given":"Veronica Siton","family":"Alcantara","sequence":"first","affiliation":[{"name":"Breast Department, KK Women\u2019s and Children\u2019s Hospital, Singapore 229899, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6102-9016","authenticated-orcid":false,"given":"Sut Mo Zachary","family":"Chan","sequence":"additional","affiliation":[{"name":"Breast Department, KK Women\u2019s and Children\u2019s Hospital, Singapore 229899, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fuh Yong","family":"Wong","sequence":"additional","affiliation":[{"name":"Division of Radiation Oncology, National Cancer Centre, Singapore 168583, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John Carson","family":"Allen","sequence":"additional","affiliation":[{"name":"Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5296-3437","authenticated-orcid":false,"given":"Geok Hoon","family":"Lim","sequence":"additional","affiliation":[{"name":"Breast Department, KK Women\u2019s and Children\u2019s Hospital, Singapore 229899, Singapore"},{"name":"Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.humpath.2019.07.008","article-title":"Synchronous and metachronous bilateral breast cancer: Clinicopathologic characteristics and prognostic outcomes","volume":"92","author":"Mruthyunjayappa","year":"2019","journal-title":"Hum. Pathol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1362","DOI":"10.1002\/(SICI)1097-0142(19970401)79:7<1362::AID-CNCR14>3.0.CO;2-Y","article-title":"Breast-conserving therapy for stage I-II synchronous bilateral breast carcinoma","volume":"79","author":"Gollamudi","year":"1997","journal-title":"Cancer"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1111\/j.1524-4741.2010.00976.x","article-title":"Bilateral breast carcinoma: Clinical characteristics and its impact on survival","volume":"16","author":"Vuoto","year":"2010","journal-title":"Breast J."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4210","DOI":"10.1200\/JCO.2006.10.5056","article-title":"Incidence and prognosis of synchronous and metachronous bilateral breast cancer","volume":"25","author":"Hartman","year":"2007","journal-title":"J. Clin. Oncol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1038\/bjc.2012.273","article-title":"Patterns of metastasis in women with metachronous contralateral breast cancer","volume":"107","author":"Vichapat","year":"2012","journal-title":"Br. J. Cancer"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"742","DOI":"10.21037\/atm-21-5400","article-title":"Clinicopathological features and prognosis of bilateral breast cancer: A single-center cohort study based on Chinese data","volume":"10","author":"Hong","year":"2022","journal-title":"Ann. Transl. Med."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1007\/s10549-015-3403-6","article-title":"Exome sequencing of contralateral breast cancer identifies metastatic disease","volume":"151","author":"Klevebring","year":"2015","journal-title":"Breast Cancer Res. Treat."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1186\/s13058-015-0608-x","article-title":"Contralateral breast cancer can represent a metastatic spread of the first primary tumor: Determination of clonal relationship between contralateral breast cancers using next-generation whole genome sequencing","volume":"17","author":"Alkner","year":"2015","journal-title":"Breast Cancer Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3289","DOI":"10.1245\/s10434-019-07543-0","article-title":"Overuse of Preoperative Staging of Patients Undergoing Neoadjuvant Chemotherapy for Breast Cancer","volume":"26","author":"Srour","year":"2019","journal-title":"Ann. Surg. Oncol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1016\/j.crad.2009.05.006","article-title":"CT staging of loco-regional breast cancer recurrence. A worthwhile practice?","volume":"64","author":"Tennant","year":"2009","journal-title":"Clin. Radiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.1002\/cam4.5021","article-title":"Breast cancer brain metastasis: Current evidence and future directions","volume":"12","author":"Sun","year":"2023","journal-title":"Cancer Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"252","DOI":"10.4274\/ejbh.galenos.2022.2022-1-2","article-title":"Clinical Significance of Radiologically Detected Small Indeterminate Extra-Mammary Lesions in Breast Cancer Patients","volume":"18","author":"Chen","year":"2022","journal-title":"Eur. J. Breast Health"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1564","DOI":"10.1200\/JCO.2010.32.7395","article-title":"Declining incidence of contralateral breast cancer in the United States from 1975 to 2006","volume":"29","author":"Nichols","year":"2011","journal-title":"J. Clin. Oncol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2908","DOI":"10.1002\/cam4.2198","article-title":"The prognostic comparison among unilateral, bilateral, synchronous bilateral, and metachronous bilateral breast cancer: A meta-analysis of studies from recent decade (2008\u20132018)","volume":"8","author":"Pan","year":"2019","journal-title":"Cancer Med."},{"key":"ref_15","first-page":"353","article-title":"Are synchronous and metachronous bilateral breast cancers different? An immunohistochemical analysis aimed at intrinsic tumor phenotype","volume":"7","author":"Senkus","year":"2013","journal-title":"Int. J. Clin. Exp. Pathol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.7314\/APJCP.2015.16.3.1007","article-title":"Impact of bilateral breast cancer on prognosis: Synchronous versus metachronous tumors","volume":"16","author":"Ibrahim","year":"2015","journal-title":"Asian Pac. J. Cancer Prev."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Londero, A.P., Bernardi, S., Bertozzi, S., Angione, V., Gentile, G., Dri, C., Minucci, A., Caponnetto, F., and Petri, R. (2014). Synchronous and metachronous breast malignancies: A cross-sectional retrospective study and review of the literature. BioMed Res. Int., 2014.","DOI":"10.1155\/2014\/250727"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1007\/s10549-022-06772-4","article-title":"Patterns of breast cancer second recurrences in patients after mastectomy","volume":"196","author":"Lim","year":"2022","journal-title":"Breast Cancer Res. Treat."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1038\/sj.bjc.6605434","article-title":"Relation of risk of contralateral breast cancer to the interval since the first primary tumour","volume":"102","author":"Rubino","year":"2010","journal-title":"Br. J. Cancer"},{"key":"ref_20","first-page":"srep02590","article-title":"The molecular and clinicopathologic characteristics of bilateral breast cancer","volume":"3","author":"Chen","year":"2013","journal-title":"Sci. Rep."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1186\/1477-7819-11-179","article-title":"H Breast ductal carcinoma in situ presenting as recurrent non-puerperal mastitis: Case report and literature review","volume":"11","author":"Liong","year":"2013","journal-title":"World J. Surg. Oncol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"521","DOI":"10.1016\/j.clbc.2021.08.006","article-title":"Usefulness of supplementary ultrasound surveillance in the detection of a second breast cancer in patients with ductal carcinoma in situ","volume":"21","author":"Almalki","year":"2021","journal-title":"Clin. Breast Cancer"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Pang, J., Yan, Z., Tan, Q.T., Allen, J.C., Wang, M., and Lim, G.H. (2024). Feasibility of Omitting Sentinel Lymph Node Biopsy in an Under-screened Cohort of Breast Cancer Patients with a Premastectomy Diagnosis of Ductal Carcinoma In Situ. Clin. Breast Cancer.","DOI":"10.1016\/j.clbc.2024.02.002"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1007\/s10549-015-3352-0","article-title":"Retrospective analysis of metastatic behaviour of breast cancer subtypes","volume":"150","author":"Halfwerk","year":"2015","journal-title":"Breast Cancer Res. Treat."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Alkner, S., Bendahl, P.O., Fern\u00f6, M., Manjer, J., and Ryd\u00e9n, L. (2011). Prediction of outcome after diagnosis of metachronous contralateral breast cancer. BMC Cancer, 11.","DOI":"10.1186\/1471-2407-11-114"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3396","DOI":"10.1245\/s10434-009-0659-2","article-title":"The role of lymph node metastasis in the systemic dissemination of breast cancer","volume":"16","author":"Nathanson","year":"2009","journal-title":"Ann. Surg. Oncol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1002\/jso.24559","article-title":"Incidence and prognosis of non-metastatic triple negative breast cancer (TNBC) among different races in Southeast Asia","volume":"115","author":"Alcantara","year":"2017","journal-title":"J. Surg. Oncol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1111\/tbj.13635","article-title":"Evaluating the preoperative breast cancer characteristics affecting the accuracy of axillary ultrasound staging","volume":"26","author":"Upadhyaya","year":"2020","journal-title":"Breast J."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1111\/tbj.12732","article-title":"Prognostic Factors for Metachronous Contralateral Breast Cancer: Implications for Management of the Contralateral Breast","volume":"23","author":"Marmor","year":"2017","journal-title":"Breast J."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Lim, G.H., Hoo, J.X., Shin, Y.C., Choo, R.Z.T., Wong, F.Y., and Allen, J.C. (2023). Is Metastatic Staging Needed for All Patients with Synchronous Bilateral Breast Cancers?. Cancers, 16.","DOI":"10.3390\/cancers16010017"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"35","DOI":"10.21037\/gs.2016.11.05","article-title":"Evaluating the performance of National Comprehensive Cancer Network (NCCN) breast and ovarian genetic\/familial high risk assessment referral criteria for breast cancer women in an Asian surgical breast clinic","volume":"6","author":"Lim","year":"2017","journal-title":"Gland Surg."}],"container-title":["Current Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/4\/145\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:22:31Z","timestamp":1760106151000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/4\/145"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,4,2]]},"references-count":31,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2024,4]]}},"alternative-id":["curroncol31040145"],"URL":"https:\/\/doi.org\/10.3390\/curroncol31040145","relation":{},"ISSN":["1718-7729"],"issn-type":[{"type":"electronic","value":"1718-7729"}],"subject":[],"published":{"date-parts":[[2024,4,2]]}}}