Application Of Competing Risk Model In The Prognostic Prediction Study Of Patients With Follicular Thyroid Carcinoma

Objective: To analyze the survival status and prognostic risk factors of patients with thyroid follicular carcinoma throuth a competitive risk model,and draw a nomogram to provide data support for the prevention,treatment and prognosis of thyroid follicular carcinoma.Methods: Survival data from patients diagnosed with primary thyroid follicular carcinoma between January 1,1988 and December 31,2015 of Surveillance,Epodemiology and End Results(SEER)program were identified and extracted for the study.Tumor-specific death was the interesting event,while death of other causes(e.g.cardiovascular disease,respiratory disease,etc.)were competing risks.Mean and median were recorded for continuous variables,while counts and percentages were calculated for categorical variables.With the help of packages such as cmprsk,survival of R software,cumulative incidence function was utilized to calculate the likelihood of death resulting from thyroid cancer and other causes,respectively.Gray’s test was conducted to examine the difference in the cumulative incidence of death between groups.A proportional subdistribution hazard model was constructed and a nomogram was built based on factors including age,gender,tumor size,pathological subtype,tumor invasion,lymph node involvement,distant metastasis,and treatment.A 10-fold cross-validation procedure was adopted to assessed discrimination and calibration of the model.Results: A total of 9,210 patients diagnosed with primary thyroid follicular carcinoma were included.The average age of the patients was 49 years,ranging from 5 to 95 years.Most patients were female(72.5%)and white(79.6%).The tumors were mostly located within the thyroid gland(56.2%),while lymph node metastases(3.7%)or distant metastases(3.0%)were less frequent.The median follow-up time was 92 months(1-347months).During the follow-up,11% of patients died,of which 4.6% died from thyroid causes and 6.4% died from other causes.The 5 ‐ year,10 ‐ year,and 20 ‐ year probabilities of death from thyroid follicular carcinoma were 02.84%,5.23%,and8.61%,respectively;The age at diagnosis,gender,tumor size,pathological subtypes,tumor extension,lymph node involvement,surgical and radiotherapy methods were related to the cumulative incidence of death,while race had no significant effect on that.Multivariate analysis indicated that aging,tumors greater than 4 cm,trabecular follicular carcinoma,extra-glandular tumor invasion,lymph node involvement,distant metastasis were risk factors for patient survival.The performance of the model was good.A nomogram was built based on the model to predict the likelihood of death in patients with thyroid follicular carcinoma.Conclusions: The prognosis of thyroid follicular carcinoma is excellent.The likelihood of death caused by thyroid cancer increases with age.Male and tumors larger than 4 cm,Invasion,extrathyroidal extension,lymph node involvement,and distant metastasis increase the risk of dying from thyroid carcinoma.A nomogram constructed based on the well-performed competing risks model is helpful for both patients and clinicians.