{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T03:09:42Z","timestamp":1769656182724,"version":"3.49.0"},"reference-count":23,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Colorectal cancer (CRC) is the third most common cancer worldwide. Accordingly, we aimed to investigate the frequency, types, and timelines of other cancers in patients diagnosed with CRC. Methods: Patients diagnosed with CRC between 1999 and 2023 were retrospectively included. We collected data on the demographics and diagnosis of any additional cancer, either prior to or following the CRC diagnosis. Data were retrieved from the Clalit database using the MDClone platform. Results: A total of 65,774 CRC patients were identified between 1999 and 2023. A second primary malignancy (SPM) was diagnosed in 13,679 patients (21%). Being female, smoking, and having chronic obstructive pulmonary disease were more frequent among patients with a SPM. Breast, prostate, and lung cancers were the most prevalent SPMs. The risk of developing SPM was highest during the first three years after CRC diagnosis, especially with respect to lung cancer, whereas the majority of breast and prostate cancers were diagnosed during the three years before CRC; the cumulative standardized incidence ratio was calculated to be 4.1 for any cancer. Conclusions: CRC patients have an increased second primary cancer. Patients diagnosed with CRC should be encouraged to undergo screening for other cancers, and those with Lynch-related cancers should be investigated for the syndrome. Patients with a diagnosis of breast or prostate cancer should be considered for colonoscopy screening.<\/jats:p>","DOI":"10.3390\/jcm15031053","type":"journal-article","created":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T15:04:46Z","timestamp":1769612686000},"page":"1053","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Second Primary Malignancies in Patients with Colorectal Cancer: The Frequency, Types, and Timeline"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-8231-8400","authenticated-orcid":false,"given":"Zlata","family":"Lerner","sequence":"first","affiliation":[{"name":"The Institute of Gastroenterology and Hepatology, Soroka University Medical Center, P.O. Box 151, Beer-Sheva 84101, Israel"},{"name":"Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah","family":"Weissmann","sequence":"additional","affiliation":[{"name":"Medical School for International Health, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heba","family":"Abu-Kaf","sequence":"additional","affiliation":[{"name":"The Institute of Gastroenterology and Hepatology, Soroka University Medical Center, P.O. Box 151, Beer-Sheva 84101, Israel"},{"name":"Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1015-6164","authenticated-orcid":false,"given":"Ali","family":"Abu-Juma","sequence":"additional","affiliation":[{"name":"The Institute of Gastroenterology and Hepatology, Soroka University Medical Center, P.O. Box 151, Beer-Sheva 84101, Israel"},{"name":"Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-6094-7757","authenticated-orcid":false,"given":"Barah","family":"Abu Gnim","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4844-3308","authenticated-orcid":false,"given":"Naim","family":"Abu-Freha","sequence":"additional","affiliation":[{"name":"The Institute of Gastroenterology and Hepatology, Soroka University Medical Center, P.O. Box 151, Beer-Sheva 84101, Israel"},{"name":"Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"998","DOI":"10.2174\/18735592MTEx9NTk2y","article-title":"Colorectal Cancer Epidemiology: Recent Trends and Impact on Outcomes","volume":"22","author":"Baidoun","year":"2021","journal-title":"Curr. Drug Targets"},{"key":"ref_2","first-page":"7","article-title":"Cancer statistics, 2018","volume":"68","author":"Siegel","year":"2018","journal-title":"CA Cancer J. Clin."},{"key":"ref_3","unstructured":"American Cancer Society (2020). Colorectal Cancer Facts & Figures 2020\u20132022, American Cancer Society. Available online: https:\/\/www.cancer.org\/content\/dam\/cancer-org\/research\/cancer-facts-and-statistics\/colorectal-cancer-facts-and-figures\/colorectal-cancer-facts-and-figures-2020-2022.pdf."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1637","DOI":"10.1136\/gutjnl-2014-309086","article-title":"Colorectal cancer screening: A global overview of existing programmes","volume":"64","author":"Schreuders","year":"2015","journal-title":"Gut"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1007\/978-1-59745-416-2_5","article-title":"Epidemiology of multiple primary cancers","volume":"471","author":"Soerjomataram","year":"2009","journal-title":"Methods Mol. Biol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"11","DOI":"10.14735\/amko201411","article-title":"Second primary cancers\u2014Causes, incidence and the future","volume":"27","author":"Hrstka","year":"2014","journal-title":"Klin. Onkol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e651","DOI":"10.1634\/theoncologist.2019-0266","article-title":"Second Primary Malignancies in Patients with Colorectal Cancer: A Population-Based Analysis","volume":"25","author":"Jia","year":"2020","journal-title":"Oncologist"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2097","DOI":"10.1007\/s11095-008-9661-9","article-title":"Cancer is a preventable disease that requires major lifestyle changes","volume":"25","author":"Anand","year":"2008","journal-title":"Pharm. Res."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Chen, Q., Zhao, S., Song, Y., Gao, P., Sun, J., Chen, X., Sun, Y., and Wang, Z. (2018). Do patients with second primary colorectal cancer hold the similar prognosis and therapeutic benefits as those with initial primary colorectal cancer?. BioMed Res. Int., 2018.","DOI":"10.1155\/2018\/6172670"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"6756","DOI":"10.18632\/aging.204250","article-title":"The risk of developing second primary malignancies among colorectal cancer patients","volume":"14","author":"Du","year":"2022","journal-title":"Aging"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Halamkova, J., Kazda, T., Pehalova, L., Gonec, R., Kozakova, S., Bohovicova, L., Krakorova, D.A., Slaby, O., Demlova, R., and Svoboda, M. (2021). Second primary malignancies in colorectal cancer patients. Sci. Rep., 11.","DOI":"10.1038\/s41598-021-82248-7"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1093\/jjco\/hyv137","article-title":"Young patients with colorectal cancer have increased risk of second primary cancers","volume":"45","author":"Liang","year":"2015","journal-title":"Jpn. J. Clin. Oncol."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Ramin, C., Veiga, L.H.S., Vo, J.B., Curtis, R.E., Bodelon, C., Aiello Bowles, E.J., Buist, D.S.M., Weinmann, S., Feigelson, H.S., and Gierach, G.L. (2023). Risk of second primary cancer among women in the Kaiser Permanente Breast Cancer Survivors Cohort. Breast Cancer Res., 25.","DOI":"10.1186\/s13058-023-01647-y"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Saltus, C.W., Vassilev, Z.P., Zong, J., Calingaert, B., Andrews, E.B., Soriano-Gabarr\u00f3, M., and Kaye, J.A. (2019). Incidence of second primary malignancies in patients with castration-resistant prostate cancer: An observational retrospective cohort study in the United States. Prostate Cancer, 2019.","DOI":"10.1155\/2019\/4387415"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"5752","DOI":"10.1002\/cam4.1764","article-title":"Prostate cancer survivors: Risk and mortality in second primary cancers","volume":"7","author":"Chattopadhyay","year":"2018","journal-title":"Cancer Med."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1076","DOI":"10.1002\/ijc.33685","article-title":"Cancer incidence and cancer death in relation to tobacco smoking in a population-based Australian cohort study","volume":"149","author":"Weber","year":"2021","journal-title":"Int. J. Cancer"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"733","DOI":"10.1038\/nrc1190","article-title":"Tobacco carcinogens, their biomarkers and tobacco-induced cancer","volume":"3","author":"Hecht","year":"2003","journal-title":"Nat. Rev. Cancer"},{"key":"ref_18","first-page":"337","article-title":"The impact of comorbidity on cancer and its treatment","volume":"66","author":"Sarfati","year":"2016","journal-title":"CA Cancer J. Clin."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1674","DOI":"10.2337\/dc10-0666","article-title":"Diabetes and cancer: A consensus report","volume":"33","author":"Giovannucci","year":"2010","journal-title":"Diabetes Care"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Rasmussen, L.A., Jensen, H., Virgilsen, L.F., Falborg, A.Z., M\u00f8ller, H., and Vedsted, P. (2019). Time from incident primary cancer until recurrence or second primary cancer: Risk factors and impact in general practice. Eur. J. Cancer Care, 28.","DOI":"10.1111\/ecc.13123"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1093\/jnci\/djh034","article-title":"Revised Bethesda Guidelines for hereditary nonpolyposis colorectal cancer (Lynch syndrome) and microsatellite instability","volume":"96","author":"Umar","year":"2004","journal-title":"J. Natl. Cancer Inst."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"971","DOI":"10.1016\/j.gim.2022.01.014","article-title":"Worldwide prevalence of Lynch syndrome in patients with colorectal cancer: Systematic review and meta-analysis","volume":"24","author":"Kaushik","year":"2022","journal-title":"Genet. Med."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"564","DOI":"10.1111\/jgh.16881","article-title":"Lynch syndrome: Similarities and differences of recommendations in published guidelines","volume":"40","author":"Hozaeel","year":"2025","journal-title":"J. Gastroenterol. Hepatol."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/3\/1053\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T15:31:58Z","timestamp":1769614318000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/3\/1053"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,28]]},"references-count":23,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["jcm15031053"],"URL":"https:\/\/doi.org\/10.3390\/jcm15031053","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,28]]}}}