Preoperative Serum Lipids as Novel Predictors of Survival in 3575 Patients With Papillary Thyroid Cancer.

Context: Papillary thyroid cancer (PTC) is an endocrine malignancy with rapidly increased rate. The relationship between lipids and PTC recurrence need further investigate.

Objective: The objective of this study is to investigate the association between preoperative serum lipids levels and the outcomes of PTC patients.

Methods: A retrospective cohort study including 3575 patients with PTC from 2012 to 2016 with follow-ups in our institute were enrolled. Preoperative serum lipids were divided into categorical variables by receiver operating curves. Univariable and multivariable Cox regression models were developed and independent risk factors were used to construct a nomogram to predict disease-free survival (DFS) rate.

Results: Among the 3575 patients, the mean follow-up time was 56.7 months. Comparing with the patients with high levels of triglyceride (TAG ≥ 0.605 mmol/L) and high-density lipoprotein (HDL ≥ 0.935 mmol/L), those with low levels of TAG (hazard ratio [HR] 2.20, 95% CI 1.30-3.72) and HDL (HR 1.60, 1.00-2.57) had a significantly higher risk of recurrence in PTCs. The 5-year DFS rate of patients with low levels of TAG was 94.4%, which was much lower than that in the high-level group (97.2%, P < .001). While cholesterol (P = .13), low-density lipoprotein (P = .07), and very low-density lipoprotein (P = .15) were not statistically correlated with recurrence of PTCs. The nomogram model showed clinical predictive value with a c-index of 0.80 (95% CI 0.73-0.87) and 0.82 (95% CI 0.73-0.90) for 3- and 4-year DFS in the training cohorts.

Conclusion: In the present study, we provide initial evidence that low levels of TAG and HDL were independently associated with the recurrence of PTC, indicating that preoperative serum concentrations of lipids are helpful in predicting the prognosis for patients with PTC in clinical practice.