{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T15:56:35Z","timestamp":1781538995252,"version":"3.54.5"},"reference-count":37,"publisher":"American Medical Association (AMA)","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"\n Importance<\/jats:title>\n More than half of Medicare beneficiaries are now enrolled in Medicare Advantage (MA) plans. These plans offer lower premiums and additional benefits compared with Traditional Medicare (TM) but commonly restrict organization and clinician networks, potentially limiting access to specialists, including oncologists. Little is known about the use of oncology networks in MA plans.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To evaluate effective oncology network breadth under MA plans based on realized health care utilization.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n This cross-sectional study used linked 2016-2019 Surveillance, Epidemiology, and End Results (SEER)\u2013Medicare data to characterize effective oncology networks among beneficiaries diagnosed with 8 common cancers. Network trends were examined separately for regular MA plans and special needs plans (SNPs) within SEER counties, and network breadth was compared by metropolitan status and plan type (health maintenance organization [HMO], local or regional preferred provider organization [PPO], point-of-service [POS] plan, or other). Data were analyzed between March 1, 2025, and April 1, 2026.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n Effective oncology network breadth was defined at the plan-county-year level as the share of oncology organizations and oncologists accessed by MA beneficiaries relative to oncology organizations and oncologists accessed by TM beneficiaries in the same county-year, measured separately for oncology organizations, medical or surgical oncologists, and radiation oncologists and more than 1 MA-recorded visit to a National Cancer Institute (NCI)\u2013designated comprehensive cancer center.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n A total of 807\u202f580 MA beneficiaries (mean [SD] age, 70.4 [9.0] years; 420 662 males [52.1%]) were identified, representing 23\u202f255 plan-year observations for regular MA plans and 17\u202f716 for SNPs from 2016 through 2019. Across regular MA plans, beneficiaries accessed a mean (SD) of 12.0% (12.7%) of oncology organizations, 6.8% (9.6%) of medical or surgical oncologists, and 11.6% (13.8%) of radiation oncologists; across SNPs, beneficiaries accessed 12.4% (12.6%) of oncology organizations, 7.2% (8.6%) of medical or surgical oncologists, and 12.7% (15.5%) of radiation oncologists. MA-recorded visits to NCI-designated comprehensive cancer centers were observed in 25.7% (n\u2009=\u20095983 of 23255) of regular MA plans and 20.5% (n\u2009=\u20093624 of 17716) of SNPs. Effective oncology network breadth was narrower for HMOs; nonmetropolitan (vs metropolitan) counties and regional PPOs (vs other plan types) had lower likelihood of MA-recorded visits to NCI-designated comprehensive cancer centers.<\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n In this cross-sectional study of MA plans in SEER regions from 2016 to 2019, effective oncology organization and oncologist networks were constrained. Restricted access to NCI-designated comprehensive cancer centers might limit access to innovative treatments and cancer outcomes, which warrants future research.<\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2026.18507","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T15:30:45Z","timestamp":1781537445000},"page":"e2618507","source":"Crossref","is-referenced-by-count":0,"title":["Oncology Organization and Oncologist Networks Under Medicare Advantage Plans"],"prefix":"10.1001","volume":"9","author":[{"given":"Xin","family":"Hu","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology, School of Medicine, Emory University, Atlanta, Georgia"},{"name":"Winship Cancer Institute, Emory University, Atlanta, Georgia"},{"name":"Department of Health Policy and Management, Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youngmin","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Health Policy, Vanderbilt University Medical Center, Nashville, Tennessee"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qinjin","family":"Fan","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kewei Sylvia","family":"Shi","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhiyuan","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingxuan","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joan L.","family":"Warren","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K. Robin","family":"Yabroff","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhanji","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, School of Medicine, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuesong","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Surveillance, Prevention, & Health Services Research, American Cancer Society, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changchuan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"issue":"9","key":"zoi260516r2","doi-asserted-by":"publisher","DOI":"10.1093\/haschl\/qxaf177","article-title":"Zero-premium Medicare Advantage plans: trends in areas with socioeconomic vulnerability and health needs.","volume":"3","author":"Jiang","year":"2025","journal-title":"Health Aff Sch"},{"issue":"18","key":"zoi260516r5","doi-asserted-by":"publisher","first-page":"3304","DOI":"10.1200\/JCO.22.02212","article-title":"Evolving landscape of metastatic cancer survivorship: reconsidering clinical care, policy, and research priorities for the modern era.","volume":"41","author":"Lai-Kwon","year":"2023","journal-title":"J Clin Oncol"},{"issue":"4","key":"zoi260516r6","doi-asserted-by":"publisher","first-page":"489","DOI":"10.1093\/jnci\/djab223","article-title":"Survivorship for individuals living with advanced and metastatic cancers: National 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