Delayed treatment for CIN 2 did not raise three-year cancer risk
National Cancer Institute researchers found monitoring CIN 2 reduced cervical excisions without increasing three-year cervical cancer risk.
By Priya Raghavan · Science Reporter
2 min read
Women diagnosed with moderate precancerous cervical cell changes did not have a lower three-year cancer risk when treated quickly with excision, according to a study published in Annals of Internal Medicine. The finding matters because delaying treatment for cervical intraepithelial neoplasia grade 2, or CIN 2, could spare some patients procedures that the study classified as unnecessary.
The American College of Physicians said the study used a target trial emulation to compare two approaches: excision within six months of diagnosis and delayed management through continued surveillance or excision after six months. The researchers reported that early excision did not reduce the three-year risk of invasive cervical cancer compared with delayed management.
Researchers from the National Cancer Institute analyzed records from 12,012 women in Kaiser Permanente Northern California’s cervical cancer screening program, according to the American College of Physicians. All were diagnosed with CIN 2 on an initial biopsy between 2017 and 2023.
What the study compared
CIN 2 is a moderate form of precancerous cervical dysplasia, according to the American College of Physicians. Because some CIN 2 lesions do not develop into cervical cancer, the best timing for treatment has been debated, the group said.
The National Cancer Institute team estimated three-year risks for several outcomes, according to the study summary. Those included unnecessary excision, CIN grade 3 or more severe disease, and invasive cervical cancer.
The study found that immediate treatment was linked with more excisions, including procedures that yielded less serious findings, according to the American College of Physicians. Delayed management reduced unnecessary procedures when paired with careful follow-up, the group said.
Possible effect on care guidelines
The authors reported that excision within six months did not improve three-year cervical cancer outcomes compared with continued surveillance or later excision. The American College of Physicians said the observations suggest delayed treatment may be safe for CIN 2, particularly for lower-risk CIN 2.
The findings could help shape U.S. guidance on how clinicians manage CIN 2, according to the American College of Physicians. The study does not say that follow-up can be skipped; its delayed-management comparison included continued surveillance or treatment after the six-month mark.
The paper, titled “Benefits and Harms of Immediate Versus Delayed Treatment of Cervical Intraepithelial Neoplasia Grade 2: A Target Trial Emulation,” was published in Annals of Internal Medicine in 2026. The American College of Physicians listed the DOI as 10.7326/ANNALS-25-04053.
This story draws on original reporting from Medical Xpress.