The development of nomogram for predicting thyroid cancer in subject with single thyroid nodule in Bali, Indonesia

Background: There were many cases of thyroid cancer proven from histopathology test after lobectomy from single thyroid nodules, which were not being predicted in advanced. The challenge for the clinician is thus to predict the malignancy preoperative to prevent unnecessary second completion thyroidectomy. Objective: This study aimed to determine the cancer probability risk of a single thyroid nodule by using preoperative parameters. Methods: This cohort study was conducted in Sanglah General Hospital, from 2016 to 2021. All data was obtained by Cancer Registry and electronic medical records. There were nine variables that being analyzed in this study, such as age, gender, side, size, consistency, vascularization, node, and cytology. The data was pooled and analyzed in SPSS and R studio. Smart phone application was developed using Android studio. Data were analyzed by logistic regression multivariate analysis. Results: From 2016-2021, there were 198 subjects with single thyroid nodules underwent surgeries in Sanglah General Hospital, Denpasar, Bali, Indonesia. As many as 98 subjects were histopathology proven cancer (follicular, papillary) after surgery. From multivariate analysis, the only left significant variables were vascularization, calcification, age, consistency, and cytology. Further, nomogram was developed to plot the probability of cancer from significant variables. By using only cytology parameter, the cancer predictive value was only less than 10%. Even age and consistency parameter by physical examination gave a higher value of 30% predictive value. The ultrasound parameters, combining the presence of calcification and vascularization, had a good predictive value of 60%. Conclusion: The combination of the ultrasound characteristics, age and physical examination able to accurately predict thyroid cancer.