Significant racial differences in the incidence and behavior of the follicular variant of papillary thyroid carcinoma

Racial and Ethnic Disparities in the Diagnosis and Treatment of Thyroid Disease

CONTEXT

There are differences in diagnosis, treatment, and outcomes for thyroid between racial and ethnic groups that contribute to disparities. Identifying these differences and their causes are the key to understanding and reducing disparities in presentation and outcomes in endocrine disorders.

EVIDENCE ACQUISITION

The present study reviews original studies identifying and exploring differences between benign and malignant thyroid diseases. A PubMed, Web of Science, and Scopus search was conducted for English-language studies using the terms "thyroid," "thyroid disease," "thyroid cancer," "race," "ethnicity," and "disparities" from inception to December 31, 2022.

EVIDENCE SYNTHESIS

Many racial and ethnic disparities in the diagnosis, presentation, treatment, and outcomes of thyroid disease were found. Non-White patients are more likely to have a later time to referral, to present with more advanced disease, to have more aggressive forms of thyroid cancer, and are less likely to receive the appropriate treatment than White patients. Overall and disease-specific survival rates are lower in Black and Hispanic populations when compared to White patients.

CONCLUSIONS

Extensive disparities exist in thyroid disease diagnosis, treatment, and outcomes that may have been overlooked. Further work is needed to identify the causes of these disparities to begin to work toward equity in the care of thyroid disease.

Disparities in the impact of the AJCC 8th edition staging system on differentiated thyroid cancer outcomes

BACKGROUND

The impact of AJCC8 among self-reported racial/ethnic groups on differentiated thyroid cancer (DTC) outcomes is unknown.

METHODS

Multivariate-regression evaluated the association between AJCC7 to AJCC8 stage change and race/ethnicity in patients with DTC in the NCDB. Cox-proportional-regression evaluated whether AJCC7 to AJCC8 stage change affects overall survival (OS) differently based on reported race/ethnicity.

RESULTS

After adjusting for confounders, Hispanics and Asian-Pacific-Islanders (APIs) were 27% and 12% less likely to be down-staged compared to white-non-Hispanics (WNHs) (p < 0.001); black-non-Hispanics (BNHs) had no significant down-staging difference. Down-staged patients had an increased risk of death compared to patients with unchanged staging, regardless of race/ethnicity. However, based on two-way interaction, the magnitude of this negative change on survival from down-staging was only different between WNHs (HR = 2.64) and BNHs (HR = 1.77), (p = 0.04).

CONCLUSIONS

Outcome disparities persist among self-reported racial/ethnic groups with AJCC8. Down-staged patients across all racial/ethnic groups had decreased survival compared to those with unchanged stage, with the least impact in BNHs.

Thyroid nodules of indeterminate cytology in Hispanic/Latinx patients

BACKGROUND

Behavior of differentiated thyroid cancer (DTC) varies among ethnic groups. Recommended management of thyroid nodules with indeterminate cytology (TN-IC) is based on molecular analysis from predominantly non-Hispanic white patients. We hypothesized that TN-IC in Hispanic/Latinx patients would have different features, management, and outcomes and that molecular testing might perform differently in Hispanic/Latinx patients.

METHODS

Retrospective chart review was performed on 127 TN-IC analyzed with Afirma. Patient characteristics were compared using linear model ANOVA and Fisher's exact test.

RESULTS

Out of 127 TN-IC, 71 (56%) were Hispanic/Latinx. Hispanic/Latinx had a greater prevalence of diabetes, but Afirma results (benign or suspicious) were similar between ethnic groups. Fourteen patients had malignant pathology. Their management and outcomes were similar across groups. The negative predictive value for our cohort (97.9%) was similar to published data.

CONCLUSIONS

Data from our predominantly-Hispanic/Latinx cohort suggest that Afirma performs similarly in Hispanic/Latinx and non-Hispanic white patients with TN-IC.

Genetic variation in POT1 and risk of thyroid subsequent malignant neoplasm: A report from the Childhood Cancer Survivor Study

BACKGROUND

Telomere length is associated with risk for thyroid subsequent malignant neoplasm in survivors of childhood cancer. Here, we investigated associations between thyroid subsequent malignant neoplasm and inherited variation in telomere maintenance genes.

METHODS

We used RegulomeDB to annotate the functional impact of variants mapping to 14 telomere maintenance genes among 5,066 five-or-more year survivors who participate in the Childhood Cancer Survivor Study (CCSS) and who are longitudinally followed for incidence of subsequent cancers. Hazard ratios for thyroid subsequent malignant neoplasm were calculated for 60 putatively functional variants with minor allele frequency ≥1% in or near telomere maintenance genes. Functional impact was further assessed by measuring telomere length in leukocyte subsets.

RESULTS

The minor allele at Protection of Telomeres-1 (POT1) rs58722976 was associated with increased risk for thyroid subsequent malignant neoplasm (adjusted HR = 6.1, 95% CI: 2.4, 15.5, P = 0.0001; Fisher's exact P = 0.001). This imputed SNP was present in three out of 110 survivors who developed thyroid cancer vs. 14 out of 4,956 survivors who did not develop thyroid cancer. In a subset of 83 survivors with leukocyte telomere length data available, this variant was associated with longer telomeres in B lymphocytes (P = 0.004).

CONCLUSIONS

Using a functional variant approach, we identified and confirmed an association between a low frequency intronic regulatory POT1 variant and thyroid subsequent malignant neoplasm in survivors of childhood cancer. These results suggest that intronic variation in POT1 may affect key protein binding interactions that impact telomere maintenance and genomic integrity.