From the Guidelines
The biopsy results of your thyroid nodule are reassuring, indicating a benign follicular nodule with a very low risk of malignancy, estimated to be between 0-3%. The findings show a cellular sample consisting of benign follicular cells with a macrofollicular arrangement of colloid, and no nuclear features of papillary thyroid carcinoma are identified. According to the report, nodules classified as benign have a low chance of being malignant. No immediate treatment is typically needed for benign thyroid nodules, but your doctor will likely recommend periodic monitoring with ultrasound examinations to ensure the nodule doesn't change over time, as suggested by the guidelines for diagnosis, treatment, and follow-up of thyroid cancer 1. This follow-up is important because, although rare, some initially benign-appearing nodules can change. If you experience symptoms like difficulty swallowing, voice changes, or if the nodule grows significantly, you should contact your doctor promptly. The most recent guidelines from 2019 suggest active surveillance as a first-line management option for low-risk papillary microcarcinoma 1, but this does not directly apply to your case since your nodule is benign. Overall, these results are favorable and should provide reassurance about your thyroid health. It is essential to continue monitoring the nodule as recommended by your doctor to ensure it does not change or grow, which would prompt a reevaluation of the nodule's nature. Given the low risk of malignancy and the benign nature of the nodule, periodic ultrasound monitoring is the most appropriate course of action at this time.
From the Research
Thyroid Nodule Biopsy Results
The patient's fine needle guided biopsy of her thyroid showed findings consistent with a benign, follicular nodule. The sample was cellular, consisting of benign follicular cells, and a macro follicular arrangement of colloid nuclear features of papillary thyroid carcinoma were not identified.
Malignancy Risk
- The risk of malignancy in benign thyroid nodules is estimated to be between 0-3% 2, 3.
- A study published in 2020 found that the overall rate of diagnosis of malignancy after a nondiagnostic FNAB was 8.1% 2.
- Another study published in 2012 found that before the routine use of FNA, approximately 14% of resected thyroid nodules were malignant, whereas with the current widespread use of thyroid nodule FNA, >50% of resected thyroid nodules are malignant 3.
Biopsy Methods
- Fine-needle aspiration biopsy (FNA) is the standard test to determine whether surgical removal of a detected nodule is recommended 3, 4.
- Core-needle biopsy (CNB) is an alternative method that can be used when FNA has poor performance, and it has a low rate of non-diagnostic and indeterminate diagnoses 5.
- Ultrasound-guided fine-needle aspiration biopsy is not necessarily required for all patients, and palpation-guided fine-needle aspiration biopsy can be used selectively for nonpalpable, predominantly cystic, or previously nondiagnostic nodules 6.
Diagnostic Accuracy
- The sensitivity of CNB for malignancy was 96% and the specificity was 93.7% 5.
- The predictive positive value for a follicular lesion diagnosis was 12.2% and for a malignancy diagnosis, 98.6% 5.
- FNA has an essential role in the evaluation of patients with thyroid nodules to reduce the rate of unnecessary thyroid surgery for patients with benign nodules and triage patients with thyroid cancer to appropriate surgery 3, 4.