CA-125 is Less Accurate in Black and American Indian People

TOPLINE:

Cancer Antigen 125 (CA-125) testing shows 23% lower odds of elevated levels in American Indian and Black patients with ovarian cancer compared with White patients. Patients with false-negative CA-125 findings experienced 9.38 days longer time to chemotherapy initiation.

METHODOLOGY:

• Current guidelines use CA-125 thresholds to recommend which patients with pelvic masses should undergo evaluation by gynecologic oncologists for ovarian cancer. Studies have shown CA-125 levels to be 10%-37% lower in healthy Black women and up to 20% lower in Native American women compared with non-Hispanic White women.
• A retrospective cohort study analyzed 250,749 patients with ovarian cancer diagnosed between January 2004 and December 2020 using the United States National Cancer Database, with a median age of 62.0 years.
• Patient demographics included 0.4% American Indian individuals, 3.7% Asian individuals, 8.6% Black individuals, 85.2% White individuals, and 2.0% individuals of other or unknown race. Additionally, 6.7% of patients were of Hispanic ethnicity, 88.8% were of non-Hispanic ethnicity, and ethnicity was unknown for 4.6% of them.
• Researchers examined CA-125 levels at diagnosis, defining them as elevated/borderline or negative/normal, with analysis adjusted for stage, comorbidities, and menopausal status.
• Analysis included multivariable logistic regression models to examine associations between patient race/ethnicity and CA-125 levels, whereas generalized linear models assessed the relationship between CA-125 levels and time to chemotherapy initiation.

TAKEAWAY:

• Among 212,477 patients with measured CA-125 levels, 88.2% had elevated levels at diagnosis, with Black patients showing lower odds of elevation (adjusted odds ratio [AOR], 0.77; 95% CI, 0.74-0.81) than White patients.
• American Indian patients demonstrated similarly reduced odds of elevated CA-125 levels (AOR, 0.77; 95% CI, 0.62-0.94), whereas Asian patients with high-grade serous cancer showed increased odds (AOR, 1.32; 95% CI, 1.10-1.57).
• Black patients specifically showed lower odds of elevated CA-125 levels in high-grade serous ovarian cancer (AOR, 0.81; 95% CI, 0.73-0.91).
• Patients with false-negative CA-125 findings experienced 9.38 days longer time to chemotherapy initiation (95% CI, 8.43-10.34 days) than those with elevated levels.

IN PRACTICE:

“Current CA-125 thresholds may miss racially and ethnically diverse patients with ovarian cancer…Work is needed to develop inclusive CA-125 thresholds and diagnostic guidelines and not compound disparities in ovarian cancer diagnosis and treatment,” the authors of the study wrote.

SOURCE:

This study was led by Anna Jo Bodurtha Smith, MD, MPH, Perelman School of Medicine, University of Pennsylvania in Philadelphia. It was published online on March 20 in JAMA Network Open.

LIMITATIONS:

The National Cancer Database includes 80% of new ovarian cancer diagnoses in the United States but excludes patients in Puerto Rico, those treated by the Veterans Health Administration, and those in small, non–National Cancer Institute–designated cancer centers. The study population may be less ethnically diverse than the full population of patients with ovarian cancer in the United States and worldwide, potentially biasing findings toward the null.

DISCLOSURES:

This study was supported by career enhancement grant 2P50CA228991-06A1 from the National Cancer Institute Ovarian Cancer Specialized Programs of Research Excellence and Paul Calabresi Career Development for Clinical Oncology award 5K12CA076931-25 from the National Cancer Institute. Bodurtha Smith disclosed receiving grants from GlaxoSmithKline, the National Cancer Institute, American Society of Clinical Oncology, Ovarian Cancer Research Alliance, and Foundation for Women’s Cancer and an honorarium from Total Health outside the submitted work.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.