Nomogram for the Prediction of Biochemical Incomplete Response in Papillary Thyroid Cancer Patients

Abstract

Purpose

To develop a nomogram for predicting biochemical incomplete response (BIR) in the dynamic risk stratification (DRS) of papillary thyroid carcinoma (PTC) patients without structural recurrence, and to investigate its validity.

Patients and Methods

Overall, 1705 (1005 and 700 in the training and validation cohorts, respectively) PTC patients treated with total thyroidectomy without structural recurrence were included. multivariate logistic regression analyses were performed to determine the significant predictors of BIR in the training cohort. A nomogram was subsequently constructed for BIR risk prediction. Assessments for the predictive accuracy, discrimination, and calibration of the nomogram were performed. Subsequently, internal and external validations were conducted.

Results

In the multivariate analysis, age, sex, lymph node metastasis site, extrathyroidal extension, and lymphovascular invasion showed significant predictive value; using these predictive factors and tumor size, a nomogram for BIR risk prediction was constructed. In the training cohort, the nomogram showed good predictive performance and discrimination in the receiver operating characteristic (ROC) curve analysis, with an area under the curve (AUC) of 0.765. In internal validation, the bootstrap-corrected AUC was 0.76. The calibration plot showed good agreement between the predicted and actual observation. The Hosmer–Lemeshow (HL) test did not suggest a lack of fit (p=0.1613). In the external validation, the AUC was 0.828 in the ROC curve analysis; the calibration plot showed good quality, and the HL test did not suggest a lack of fit (p=0.2161).

Conclusion

The constructed nomogram may effectively predict the risk of BIR in DRS in PTC patients without structural recurrence.

Level of Evidence

Level 4.

Keywords:

• papillary thyroid carcinoma
• dynamic risk stratification
• nomogram
• biochemical incomplete response

Ethics Approval and Informed Consent

This study was approved by the Institutional Review Board (IRB) of St. Vincent’s Hospital (IRB No. XC20RADE0141). All procedures involving human participants were in accordance with the ethical standards of the institutional research committee and the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. All participants provided written informed consent for storing medical information in the hospital database and use of this information for research purposes.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas, took part in drafting, revising or critically reviewing the article, gave final approval of the version to be published, have agreed on the journal to which the article has been submitted, and agree to be accountable for all aspects of the work.

Disclosure

The authors have no conflicts of interest for this work to declare.