{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T23:05:00Z","timestamp":1784675100015,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,17]],"date-time":"2023-03-17T00:00:00Z","timestamp":1679011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"miteinander gegen Krebs e.V.","award":["W\/2-LFFP 21\/13"],"award-info":[{"award-number":["W\/2-LFFP 21\/13"]}]},{"name":"federal state of Saarland","award":["W\/2-LFFP 21\/13"],"award-info":[{"award-number":["W\/2-LFFP 21\/13"]}]},{"name":"intramural funds of the Saarland University Medical Center","award":["W\/2-LFFP 21\/13"],"award-info":[{"award-number":["W\/2-LFFP 21\/13"]}]},{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)","award":["W\/2-LFFP 21\/13"],"award-info":[{"award-number":["W\/2-LFFP 21\/13"]}]},{"name":"Saarland University within the \u201aOpen Access Publication Funding\u2018 program","award":["W\/2-LFFP 21\/13"],"award-info":[{"award-number":["W\/2-LFFP 21\/13"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>(1) Background: Vitamin D plays an important role in many types of cancer. It was the aim of this study to analyze serum 25-hydroxyvitamin D (25(OH)D) levels in newly diagnosed breast cancer patients, and the association with prognostic and lifestyle factors. (2) Methods: 110 non-metastatic breast cancer patients were included in the prospective observational \u201cBEGYN\u201d study at Saarland University Medical Center between September 2019 and January 2021. At the initiation visit, serum 25(OH)D levels were measured. Clinicopathological data on prognosis, nutrition, and lifestyle were extracted from data files and obtained using a questionnaire. (3) Results: Median serum 25(OH)D in breast cancer patients was 24 ng\/mL (range 5\u201365 ng\/mL), with 64.8% of patients being vitamin D deficient. 25(OH)D was higher among patients that reported the use of vitamin D supplements (43 ng\/mL versus 22 ng\/mL; p &lt; 0.001), and in summer compared to other seasons (p = 0.03). Patients with moderate vitamin D deficiency were less likely to have triple negative breast cancer (p = 0.047). (4) Conclusions: Routinely measured vitamin D deficiency is common in breast cancer patients and needs to be detected and treated. However, our results do not support the hypothesis that vitamin D deficiency may be a main prognostic factor for breast cancer.<\/jats:p>","DOI":"10.3390\/nu15061450","type":"journal-article","created":{"date-parts":[[2023,3,17]],"date-time":"2023-03-17T02:59:26Z","timestamp":1679021966000},"page":"1450","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Prevalence and Relevance of Vitamin D Deficiency in Newly Diagnosed Breast Cancer Patients: A Pilot Study"],"prefix":"10.3390","volume":"15","author":[{"given":"Cosima","family":"Zemlin","sequence":"first","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Altmayer","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline","family":"Stuhlert","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia Theresa","family":"Schleicher","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carolin","family":"W\u00f6rmann","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Lang","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura-Sophie","family":"Scherer","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ida Clara","family":"Thul","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lisanne Sophie","family":"Spenner","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jana Alisa","family":"Simon","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alina","family":"Wind","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1771-8479","authenticated-orcid":false,"given":"Elisabeth","family":"Kaiser","sequence":"additional","affiliation":[{"name":"Department of General Pediatrics and Neonatology, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7620-2432","authenticated-orcid":false,"given":"Regine","family":"Weber","sequence":"additional","affiliation":[{"name":"Department of General Pediatrics and Neonatology, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1005-4873","authenticated-orcid":false,"given":"Sybelle","family":"Goedicke-Fritz","sequence":"additional","affiliation":[{"name":"Department of General Pediatrics and Neonatology, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gudrun","family":"Wagenpfeil","sequence":"additional","affiliation":[{"name":"Institute for Medical Biometry, Epidemiology and Medical Informatics (IMBEI), Saarland University, Campus Homburg, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9528-7419","authenticated-orcid":false,"given":"Michael","family":"Zemlin","sequence":"additional","affiliation":[{"name":"Department of General Pediatrics and Neonatology, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erich-Franz","family":"Solomayer","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00f6rg","family":"Reichrath","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Venereology and Allergology, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3488-5073","authenticated-orcid":false,"given":"Carolin","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Department of Gynecology, Obstetrics & Reproductive Medicine, Saarland University Medical Center, 66421 Homburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Gr\u00f6ber, U., Holzhauer, P., Kisters, K., Holick, M.F., and Adamietz, I.A. 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