The Birmingham Formula is not a Reliable Instrument for Preoperative Prediction of Thyroid Malignancy (Prospective Study)

Objective: Thyroid nodules are very common in population all around the world. Preopoerative anticipation of malignancy in a thyroid nodule is crucial for optimum management. There are limitations for all available tests especially in follicular tumors. The Birmingham formula was described to predict the malignancy risk in each individual with a thyroid nodule depending on phenotyping association. We tried to explore prospectively the predictivity of this formula in comparison with the postoperative pathological report. Methods: Data for 512 patients with a thyroid nodular disease, planned for surgery, were collected 399 of which were included in the study. Malignancy risk was calculated for each patient and compared to postoperative pathology report. Results: Statistical analysis showed a low sensitivity and a positive predictive value of around 50%, the performance of the formula did not improve when we excluded microcarcinoma. Conclusions: Data did not support the efficacy of Birmingham formula as a reliable instrument in predicting malignancy in thyroid nodules.