Prognosis of FTC compared to PTC and FVPTC: findings based on SEER database using propensity score matching analysis

Abstract

The significance of prognosis of follicular thyroid cancer (FTC) compared to other subtypes of thyroid cancer, based on large cohort data has only been addressed in a few studies, and the results remain controversial. In this study, we investigated the prognosis of FTC compared to papillary thyroid carcinoma (PTC) and follicular variant PTC (FVPTC) based on Surveillance, Epidemiology, and End Results database (SEER) Program data using propensity score matching. We evaluated data from 128,703 patients with thyroid cancer who were included in the SEER database between 2004 and 2013. Patient mortality was evaluated using Cox proportional hazards regression analyses and Kaplan-Meier analyses with log-rank tests. The average prognosis of FTC was poorer than both PTC and FVPTC. The multivariate Cox regression analysis revealed that the cancer-specific survival rate for FTC was lower than that for PTC and FVPTC without adjusting for risk factors. Furthermore, after propensity score matching analysis for relevant factors, the cancer-specific mortality rate for FTC was higher than that for PTC and FVPTC. These results based on a large population cohort database provide a benefit reference for individual and precise treatment and management of patients with FTC.

Keywords: Prognosis; SEER; cancer-specific survival; follicular thyroid cancer; propensity score matching.

Figure 1

Kaplan Meier curves among patients stratified by subtype for cancer-specific mortality (A-C) and all cause mortality (D-F).

Figure 2

Kaplan Meier curves of cancer-specific mortality for matched subtype pairs. Age, sex and race matching between FTC and PTC (A), FTC and FVPTC (B).

Figure 3

Kaplan Meier curves of cancer-specific mortality for matched subtype pairs. Age, sex, race, T/N/M stage, multifocality, extension matched between FTC and PTC (A), FTC and FVPTC (B).

Figure 4

Kaplan Meier curves of cancer-specific mortality for matched subtype pairs. Age, sex, race, T/N/M stage, multifocality, extension, surgery and radiation treatment matched between FTC and PTC (A), FTC and FVPTC (B).

Figure 5

Kaplan Meier curves of all cause mortality for matched subtype pairs. Age, sex and race matching between FTC and PTC (A), FTC and FVPTC (B).

Figure 6

Kaplan Meier curves of all cause mortality for matched subtype pairs. Age, sex, race, T/N/M stage, multifocality, extension matching between FTC and PTC (A), FTC and FVPTC (B).

Figure 7

Kaplan Meier curves of all cause mortality for matched subtype pairs. Age, sex, race, T/N/M stage, multifocality, extension, surgery and radiation treatment matching between FTC and PTC (A), FTC and FVPTC (B).