{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T12:51:58Z","timestamp":1765889518458,"version":"3.41.2"},"reference-count":58,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2025,7,18]],"date-time":"2025-07-18T00:00:00Z","timestamp":1752796800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004755","name":"EMD Serono","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004755","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Objective<\/jats:title>\n<jats:p>This study examined the prevalence of pre-existing chronic conditions and their association with the receipt of specific cancer-directed treatments among older adults with incident primary Merkel Cell Carcinoma (MCC) using novel predictive and interpretable machine learning methods.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>We adopted a retrospective cohort study design with data from linked Surveillance, Epidemiology, and End Results (SEER) registry and Medicare Fee-For-Service claims databases of older adults (\u2265 66 years) diagnosed with primary incident MCC between 2008 and 2017. The study cohort consisted of 1,668 older adults with incident MCC and continuous fee-for-service Medicare enrollment for 24 months. Chronic conditions were identified during 12 months before cancer diagnosis date. Type of any MCC treatment (surgery-SRx, radiotherapy-RTx, chemotherapy-CTx, immunotherapy-ITx, and hormonal therapy-HTx) were derived for 12 months following cancer diagnosis. Receipt of any of these treatments and their associations with pre-existing chronic conditions were analyzed using separate eXtreme Gradient Boosting (XGBoost) predictive models and SHapley Additive exPlanations (SHAP) methods.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>High cholesterol (75.5%), HIV (71.5%), hypertension (67.7%), arthritis (54.9%), coronary artery disease (47.1%), diabetes (43.5%), and hepatitis (37.1%) were some of the highly prevalent pre-existing chronic conditions. MCC treatment varied by type of chronic conditions and treatment modality. For example, a lower percentage of those with hypertension received ITx compared to those without hypertension (5.7% vs. 17.1%). A higher percentage of those with high cholesterol (13.9% vs 10.8%) received HTx compared to those without high cholesterol. XGBoost predictions revealed high predictive accuracy (area under the curve ranged from 0.72 (CTx) to 0.99 (ITx)). Hypertension (ITx), diabetes and thyroid disorders (HTx), congestive heart failure (RTx), and high cholesterol (CTx) were among the top ten predictors of MCC treatment. Congestive heart failure (RTx), hypertension (CTx), heart disease (ITx), thyroid disorders (HTx), and osteoporosis (HTx) positively predicted treatment, whereas high cholesterol (CTx), hypertension (ITx, HTx) and diabetes (ITx, HTx) negatively predicted treatment.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Pre-existing conditions were highly prevalent among older MCC adults. Cardiovascular and metabolic diseases were the top 10 leading predictors of cancer treatment. However, the associations varied by type of treatment. In spite of the good performance of the model, especially for ITx and HTx, there is a need to replicate these findings using other data sources that provide access to larger population subgroups.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0327964","type":"journal-article","created":{"date-parts":[[2025,7,18]],"date-time":"2025-07-18T17:45:52Z","timestamp":1752860752000},"page":"e0327964","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Type of pre-existing chronic conditions and their associations with Merkel cell carcinoma (MCC) treatment: Prediction and interpretation using machine learning methods"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6642-1073","authenticated-orcid":true,"given":"Yves Paul Vincent","family":"Mbous","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zasim Azhar","family":"Siddiqui","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Murtuza","family":"Bharmal","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Traci","family":"LeMasters","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joanna","family":"Kolodney","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0595-4148","authenticated-orcid":true,"given":"George A.","family":"Kelley","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khalid","family":"Kamal","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Usha","family":"Sambamoorthi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,7,18]]},"reference":[{"key":"pone.0327964.ref001","article-title":"Merkel Cell Carcinoma Review","author":"Y Xue","year":"2019","journal-title":"Hematology\/Oncology Clinics of North America"},{"key":"pone.0327964.ref002","article-title":"Merkel cell carcinoma: changing incidence trends","author":"NC Hodgson","year":"2005","journal-title":"J Surg Oncol"},{"key":"pone.0327964.ref003","article-title":"A Comparative study of merkel cell carcinoma and melanoma incidence and survival in the United States, 2000\u20132021","author":"JT Tribble","year":"2025","journal-title":"J Invest Dermatol"},{"issue":"6","key":"pone.0327964.ref004","doi-asserted-by":"crossref","first-page":"782","DOI":"10.6004\/jnccn.2018.7049","article-title":"Advances in immunotherapy for metastatic merkel cell carcinoma: a clinician\u2019s guide","volume":"16","author":"KG Paulson","year":"2018","journal-title":"J Natl Compr Canc Netw"},{"key":"pone.0327964.ref005","article-title":"Merkel cell carcinoma: current US incidence and projected increases based on changing demographics","author":"KG Paulson","year":"2018","journal-title":"J Am Acad Dermatol"},{"key":"pone.0327964.ref006","article-title":"Cancer treatments: past, present, and future","author":"D Sonkin","year":"2024","journal-title":"Cancer Genet"},{"key":"pone.0327964.ref007","unstructured":"National Comprehensive Cancer Network. 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Keating","year":"2008","journal-title":"J Clin Oncol"},{"issue":"2","key":"pone.0327964.ref017","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1016\/j.jamcollsurg.2008.10.016","article-title":"Impact of patient age and comorbidity on surgeon versus oncologist preferences for adjuvant chemotherapy for stage III colon cancer","volume":"208","author":"MK Krzyzanowska","year":"2009","journal-title":"J Am Coll Surg"},{"issue":"2","key":"pone.0327964.ref018","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.critrevonc.2010.01.002","article-title":"The influences of age and co-morbidities on treatment decisions for patients with HER2-positive early breast cancer","volume":"76","author":"A Ring","year":"2010","journal-title":"Crit Rev Oncol Hematol"},{"issue":"7","key":"pone.0327964.ref019","doi-asserted-by":"crossref","first-page":"1325","DOI":"10.1093\/annonc\/mdv025","article-title":"Consideration of comorbidity in treatment decision making in multidisciplinary cancer team meetings: a systematic review","volume":"26","author":"J Stairmand","year":"2015","journal-title":"Ann Oncol"},{"issue":"7","key":"pone.0327964.ref020","doi-asserted-by":"crossref","first-page":"1147","DOI":"10.1158\/0008-5472.CAN-22-1336","article-title":"A systematic review and multilevel regression analysis reveals the comorbidity prevalence in cancer","volume":"83","author":"CEJ Vrinzen","year":"2023","journal-title":"Cancer Res"},{"key":"pone.0327964.ref021","article-title":"Defining and measuring chronic conditions: imperatives for research, policy, program, and practice","author":"RA Goodman","year":"2013","journal-title":"Prev Chronic Dis"},{"key":"pone.0327964.ref022","author":"NIH National Cancer Institute","year":"2023"},{"key":"pone.0327964.ref023","author":"NIH National Cancer Institute","year":"2023"},{"issue":"1","key":"pone.0327964.ref024","doi-asserted-by":"crossref","DOI":"10.13008\/2151-2957.1297","article-title":"Addressing the social determinants of health: \u201cvulnerable\u201d populations and the presentation of Healthy People 2020","volume":"15","author":"E Rodriguez","year":"2020","journal-title":"Poroi"},{"key":"pone.0327964.ref025","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1186\/1472-6963-13-176","article-title":"Measuring fragmentation of ambulatory care in a tripartite healthcare system","volume":"13","author":"S Liu","year":"2013","journal-title":"BMC Health Serv Res"},{"key":"pone.0327964.ref026","unstructured":"XGBoost Documentation \u2014 xgboost 1.5.2 documentation. 2021."},{"key":"pone.0327964.ref027","article-title":"A unified approach to interpreting model predictions","author":"SM Lundberg","year":"2017","journal-title":"Adv Neural Inf Process Syst"},{"issue":"2","key":"pone.0327964.ref028","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1016\/j.cjca.2021.09.004","article-title":"Opening the black box: the promise and limitations of explainable machine learning in cardiology","volume":"38","author":"J Petch","year":"2022","journal-title":"Can J Cardiol"},{"key":"pone.0327964.ref029","unstructured":"Pant A. 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Towards Data Science. 2019."},{"issue":"4","key":"pone.0327964.ref030","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1145\/3343440","article-title":"A systematic review on imbalanced data challenges in machine learning: Applications and solutions","volume":"52","author":"H Kaur","year":"2019","journal-title":"ACM Computing Surveys"},{"issue":"1","key":"pone.0327964.ref031","doi-asserted-by":"crossref","DOI":"10.1186\/s40537-019-0192-5","article-title":"Survey on deep learning with class imbalance","volume":"6","author":"JM Johnson","year":"2019","journal-title":"J Big Data"},{"key":"pone.0327964.ref032","doi-asserted-by":"crossref","first-page":"737842","DOI":"10.3389\/fonc.2021.737842","article-title":"Merkel cell carcinoma: evaluation of the clinico-pathological characteristics, treatment strategies and prognostic factors in a monocentric retrospective series (n=143)","volume":"11","author":"M Rastrelli","year":"2021","journal-title":"Front 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Cheraghlou","year":"2023","journal-title":"J Am Acad Dermatol"},{"issue":"5","key":"pone.0327964.ref039","doi-asserted-by":"crossref","first-page":"540","DOI":"10.1001\/jamadermatol.2021.0247","article-title":"Association between surgical margins larger than 1\u2009cm and overall survival in patients with merkel cell carcinoma","volume":"157","author":"N Andruska","year":"2021","journal-title":"JAMA Dermatol"},{"issue":"2","key":"pone.0327964.ref040","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1002\/jso.25931","article-title":"The association between facility volume and overall survival in patients with Merkel cell carcinoma","volume":"122","author":"EJ Yoshida","year":"2020","journal-title":"J Surg Oncol"},{"issue":"7","key":"pone.0327964.ref041","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1001\/jamadermatol.2013.8116","article-title":"Effect of host, tumor, diagnostic, and treatment variables on outcomes in a large cohort with Merkel cell 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NCCN Guidelines Version 1.2023 Merkel Cell Carcinoma. 2023."},{"issue":"19","key":"pone.0327964.ref046","doi-asserted-by":"crossref","first-page":"3428","DOI":"10.1002\/cncr.32336","article-title":"Effect of fragmentation of cancer care on treatment use and survival in hepatocellular carcinoma","volume":"125","author":"CA Hester","year":"2019","journal-title":"Cancer"},{"issue":"11","key":"pone.0327964.ref047","doi-asserted-by":"crossref","first-page":"2837","DOI":"10.1002\/cncr.26601","article-title":"Understanding fragmentation of prostate cancer survivorship care: implications for cost and quality","volume":"118","author":"TA Skolarus","year":"2012","journal-title":"Cancer"},{"issue":"2","key":"pone.0327964.ref048","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1080\/20476965.2018.1436909","article-title":"Multi-disciplinary planning in health care: a review","volume":"9","author":"AG Leeftink","year":"2020","journal-title":"Health Systems"},{"key":"pone.0327964.ref049","article-title":"Time and effort in care coordination for patients with complex health and social needs: lessons from a community-based intervention","volume":"15","author":"Z Martinez","year":"2019","journal-title":"J Interprof Educ Pract"},{"key":"pone.0327964.ref050","first-page":"3","volume-title":"Simplifying care for complex patients","author":"EA Bayliss","year":"2012"},{"issue":"13","key":"pone.0327964.ref051","doi-asserted-by":"crossref","DOI":"10.1056\/NEJMra2212850","article-title":"Where medical statistics meets artificial intelligence","volume":"389","author":"DJ Hunter","year":"2023","journal-title":"N Engl J Med"},{"key":"pone.0327964.ref052","doi-asserted-by":"crossref","first-page":"9363","DOI":"10.2147\/CMAR.S220976","article-title":"Benefits and limitations of a multidisciplinary approach in cancer patient management","volume":"12","author":"R Berardi","year":"2020","journal-title":"Cancer Manag Res"},{"issue":"1","key":"pone.0327964.ref053","doi-asserted-by":"crossref","first-page":"572","DOI":"10.1186\/s12913-017-2504-9","article-title":"Comparing chronic condition rates using ICD-9 and ICD-10 in VA patients FY2014-2016","volume":"17","author":"J Yoon","year":"2017","journal-title":"BMC Health Serv Res"},{"key":"pone.0327964.ref054","doi-asserted-by":"crossref","first-page":"1129","DOI":"10.2147\/CLEP.S269400","article-title":"Impact of the transition from ICD-9-CM to ICD-10-CM on the identification of pregnancy episodes in US Health Insurance Claims Data","volume":"12","author":"A Sarayani","year":"2020","journal-title":"Clin Epidemiol"},{"issue":"120","key":"pone.0327964.ref055","first-page":"1","article-title":"Evaluation of transition from ICD-9-CM to ICD-10-CM diagnosis coding system in the National Ambulatory Medical Care Survey","author":"DT Lau","year":"2018","journal-title":"Natl Health Stat Report"},{"issue":"1","key":"pone.0327964.ref056","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1186\/s40621-021-00298-x","article-title":"Impact of ICD-9-CM to ICD-10-CM coding transition on trauma hospitalization trends among young adults in 12 states","volume":"8","author":"YV Sebasti\u00e3o","year":"2021","journal-title":"Inj Epidemiol"},{"issue":"4","key":"pone.0327964.ref057","doi-asserted-by":"crossref","DOI":"10.1016\/j.ajog.2021.03.036","article-title":"Impact of the ICD-9-CM to ICD-10-CM transition on the incidence of severe maternal morbidity among delivery hospitalizations in the United States","volume":"225","author":"A Metcalfe","year":"2021","journal-title":"Am J Obstet Gynecol"},{"issue":"3","key":"pone.0327964.ref058","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1177\/1077558706287042","article-title":"Hospital inpatient costs for adults with multiple chronic conditions","volume":"63","author":"B Friedman","year":"2006","journal-title":"Med Care Res Rev"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0327964","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,7,18]],"date-time":"2025-07-18T17:45:59Z","timestamp":1752860759000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0327964"}},"subtitle":[],"editor":[{"given":"Xiaoen","family":"Wei","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2025,7,18]]},"references-count":58,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2025,7,18]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0327964","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,18]]}}}