BOSTON – Access to and acceptance of thyroid cancer surgery varies by race, with black patients in particular appearing to be disadvantaged, compared with whites, investigators reported.
A review of data on nearly 138,000 patients diagnosed with thyroid cancer showed that blacks were significantly less likely than were whites to be offered surgery – despite its generally excellent outcomes and low rates of morbidity and mortality, reported Dr. Herbert Castillo Valladares and his colleagues from the department of surgery at the Yale University in New Haven, Conn.
American Indians/Alaskan natives and Asian/Pacific Islanders were significantly more likely to refuse surgery than were whites, the investigators also reported in a poster session at the Society of Surgical Oncology annual cancer symposium.
“In this project, we wanted to focus on the provider-level factors that might be perpetuating these racial disparities, and it appears that we need to educate some providers about the recommendation of surgery or how to educate patients who refuse thyroid cancer surgery,” Dr. Valladares said in an interview.
The investigators noted that although incidence and prevalence rates of thyroid cancer are similar among various racial groups, survival differs by race, and they wanted to find out why. To do so, they polled the Surveillance, Epidemiology, and End Results (SEER) registry to identify 137,483 patients diagnosed with thyroid cancer during 1988-2012. Results were stratified by thyroid cancer type, either papillary, medullary, follicular, or anaplastic.
In all, 82% of the sample were white, 75% were female, 87% had a diagnosis of papillary thyroid cancer, and 95% underwent thyroid cancer surgery.
In logistic regression analysis that controlled for race, the investigators found that blacks, Asian/Pacific Islanders, and persons of unknown race were significantly less likely than whites were to have thyroid cancer surgery (odds ratios, 0.7, 0.82, and 0.34, respectively; P for each less than .0001).
Similarly, surgery was more frequently not recommended for blacks (OR, 1.34; P less than .0001), Asian/Pacific Islanders (OR, 1.2; P = .004) and those of unknown race (OR, 3.06; P less than .0001).
American Indians/Alaskan natives and Asian/Pacific Islanders were also significantly more likely than were whites to refuse surgery (OR, 4.45; P = .0001; OR, 2.96; P less than .0001, respectively).
Compared with whites, blacks – but not other races – had significantly worse 5-year survival (hazard ratio, 1.14; P = .0002).
In an analysis by cancer type, the investigators saw that race was not a predictor for surgery recommendation or refusal of surgery by patients with medullary or anaplastic cancer. However, among patients with papillary thyroid cancer, the most common type, surgery was recommended less often for blacks (OR, 1.2), Asian/Pacific Islanders (OR, 1.3), and patients of unknown race (OR, 3.1; all comparisons significant by 95% confidence interval).
Among patients with follicular histology, patients of unknown race were significantly less likely than were whites to have the surgery recommended (OR, 2.7; significant by 95% CI).
Dr. Valladares explained that the SEER data set does not include information about provider type, such as those in community based versus academic settings, so the next step will be to find a method for analyzing factors at both the patient level and the provider level that might influence recommendations for surgery or patient refusals to accept surgery.
The study was supported by the Paul H. Lavietes, M.D., Summer Research Fellowship of Yale University. The investigators reported no relevant conflicts of interest.