Diagnostic accuracy of preoperative palpation- versus ultrasound-guided thyroid fine needle aspiration cytology: an observational study

Relationship of age and gender with cytopathological findings of thyroid nodules diagnosed by FNAC: a retrospective study

In Afghanistan, there are no reliable epidemiological data available about thyroid cytopathology and its possible relationship with the age and gender of patients. Therefore, we conducted this study to outline this relationship and the importance of fine needle aspiration cytology in this regard. A retrospective review study was conducted including 686 consecutive medical records of thyroid nodules diagnosed by fine needle aspiration cytology in a span of five years. Out of 686 consecutive patients with thyroid nodules included in this study, 566 were females and 120 were males. Most of the thyroid nodules diagnosed were benign lesions with female predominance. These nodules were commonly arising in between 3rd and 6th decades of life in both the genders with mean age of 42 ± 13 years in females and 52 ± 15 years in males. Thyroid malignancy was commonly diagnosed in middle-age females, however in males, it was frequently diagnosed in older age with a peak at 7th decade. Most of the malignant nodules were solid and complex with no purely cystic nature. In both the genders, thyroid nodules were commonly arising in the right thyroid lobe (52.3%), followed by left (35.7%), isthmus (8.7%) and bilateral (3.2%). Fine needle aspiration cytology remains the modality of choice for the diagnostic evaluation of nodular lesions of thyroid. In contrast to the data reported around the world, thyroid malignancies, in our study, were diagnosed in relatively older age groups with peak incidence in the 5th decade of life for females and 7th decade for males.

Risk of malignancy in thyroid nodules with indeterminate (THY3f) cytology

BACKGROUND

Fine-needle aspiration cytology (FNAC) is an integral part of thyroid nodule assessment. Nodules with an indeterminate cytology (THY3a-f) require formal histological assessment to confirm benign or malignant pathology. This study aimed to provide data for an evidence-based approach for management of patients with THY3f nodules.

METHODS

Retrospective review of patients who had a thyroid FNAC reported as suspicious of follicular neoplasm (THY3f) or showing atypia (THY3a) were identified, and clinical, operative and outcomes data were analysed.

RESULTS

Between 2018 and 2020, 200 patients (167F:33M, median age 51 years (range:18-86 years)) had a THY3f cytology. Most presented with a palpable nodule (n=104; 68.4%). Overall, 152 (76.0%;130F:23M) underwent surgery and 31 (20.4%) were found to have a thyroid carcinoma (22 follicular carcinomas, 7 papillary carcinomas, 1 medullary thyroid carcinoma and 1 metastatic renal carcinoma). An additional incidental carcinoma (size: 0.7-13mm) was found in seven (4.6%). Among those with cancer, a completion thyroidectomy and radioactive iodine treatment was indicated in nine (<6% of the entire cohort). Previously suggested risk factors for malignancy, eg male gender, large tumour size (>4cm) or age, were not found to be associated with increased risk. During the same period, THY3a cytology was reported in 53 patients, of whom 29 underwent diagnostic surgery and 4 patients were found to have a thyroid cancer (follicular, n=3 and medullary, n=1).

CONCLUSION

One in five patients with features suspicious of a follicular neoplasm (THY3f) has a thyroid carcinoma. This risk is much lower for THY3a. This study reinforces the current recommendation for thyroid surgery in all patients with a reliable THY3f cytology, as no further stratifying risk factors could be identified.

Diagnostic accuracy of palpation versus ultrasound-guided fine needle aspiration biopsy for diagnosis of malignancy in thyroid nodules: a systematic review and meta-analysis

Thyroid nodule is a common health problem in endocrinology. Thyroid fine-needle aspiration biopsy (FNAB) cytology performed by palpation guided FNAB (PGFNAB) and ultrasound-guided FNAB (USGFNAB) are the preferred examinations for the diagnosis of thyroid cancer and part of the integration of the current thyroid nodule assessment. Although studies have shown USGFNAB to be more accurate than PGFNAB, inconsistencies from several studies and clinical guidelines still exist.The purpose of this study is to compare the diagnostic accuracy of Palpation versus Ultrasound-Guided Fine Needle Aspiration Biopsy in diagnosing malignancy of thyroid nodules.The systematic review and meta-analysis were prepared based on the PRISMA standards. Literature searches were carried out on three online databases (Pubmed/MEDLINE, Embase, and Proquest) and grey literatures. Data extraction was carried out manually from various studies that met the eligibility, followed by analysis to obtain pooled data on sensitivity, specificity, Diagnostic Odds Ratio (DOR) and Area Under Curve (AUC), and the comparison of the two methods.Total of 2517 articles were obtained, with 11 studies were included in this systematic review. The total sample was 2382, including 1128 subjects using PGFNAB and 1254 subjects using USGFNAB. The risk of bias was assessed using QUADAS-2 with mild-moderate results. The results of sensitivity, specificity, AUC and DOR in diagnosing thyroid nodules using PGFNAB were 76% (95% CI, 49-89%), 77% (95% CI, 56-95%), 0.827 and 11.6 (95% CI, 6-21) respectively. The results of sensitivity, specificity, AUC and DOR in diagnosing thyroid nodules using USGFNAB were 90% (95% CI, 81-95%), 80% (95% CI, 66-89%), 0.92 and 40 (95% CI, 23-69), respectively the results of the comparison test between PGFNAB and USGFNAB; Tsens USGFNAB of 0.99 (p = 0.023), AUC difference test of 0.093 (p = 0.000023).The diagnostic accuracy of USGFNAB is higher than PGFNAB in diagnosing malignancy of thyroid nodules. If it is accessible, the author recommends using USGFNAB as a diagnostic tool for thyroid nodules.

Comparison of diagnostic value of SWE, FNA and BRAF gene detection in ACR TI-RADS 4 and 5 thyroid nodules

OBJECTIVES: To compare the diagnostic value of shear wave elastography (SWE), fine needle aspiration (FNA) and BRAF gene detection (BRAFV600E gene mutation detection) in ACR TI-RADS 4 and 5 thyroid nodules. METHODS: SWE images, FNA cytological results and BRAF detection results of ACR TI-RADS 4 and 5 thyroid nodules confirmed by pathology were analyzed retrospectively. The receiver operating characteristic (ROC) curve was drawn to determine the best cutoff value of SWE Emax. In the combined diagnosis of SWE, FNA and BRAF, firstly, the nodules with BRAF gene mutation were included in the positive ones, secondly, the nodules with benign and malignant FNA were included in the FNA + SWE or FNA + SWE + BRAF negative and positive ones respectively, finally, for FNA uncertain nodules: those whose SWE Emax were less than or equal to the cutoff value were included in FNA + SWE or FNA + SWE + BRAF negative ones, and those whose SWE Emax were greater than the cutoff value were included in positive ones. The diagnostic efficacy of SWE, FNA, SWE + FNA, FNA + BRAF and their combination in ACR TI-RADS 4 and 5 thyroid nodules were compared. RESULTS: The ROC curve showed that the best cutoff value of SWE Emax was 40.9 kpa, and the area under ROC curve (AUC) was 0.842 (0.800∼0.885). The sensitivity, specificity and accuracy of SWE were 76.3% (270/354), 75.5% (80/106) and 76.1% (350/460), respectively. The sensitivity, specificity and accuracy of FNA were 58.2% (206/354), 88.7% (94/106) and 65.2(300/460), respectively. The sensitivity, specificity and accuracy of FNA + BRAF were 95.5% (338/354), 88.7% (94/106) and 93.9% (432/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA were 85.9% (304/354), 98.1% (104/106) and 88.7% (408/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA + BRAF were 98.3% (348/354), 98.1% (104/106) and 98.3% (452/460), respectively. For the diagnostic accuracy, SWE + FNA + BRAF >  FNA + BRAF >  FNA + SWE >  SWE >  FNA, the difference was statistically significant (all P >  0.05). CONCLUSIONS: For ACR TI-RADS 4 and 5 thyroid nodules, SWE and FNA have high diagnostic efficiency. For the diagnostic accuracy, FNA + BRAF is better than FNA + SWE. FNA combination with BRAF gene detection further improves the diagnostic sensitivity and accuracy of FNA. The combined application of the three is the best.

Increased diagnostic sensitivity of palpation-guided thyroid nodule fine-needle aspiration cytology by BRAF V600E-mutation analysis

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer and its incidence is increasing. Preoperative diagnosis is warranted in order to avoid 'two-stage' procedures that are associated with additional costs and higher radioactive iodine remnant uptake. In the setting of thyroid cancer, somatic BRAF V600E-mutations are highly specific for PTC and can be analyzed in aspirates from fine-needle aspiration cytology (FNAC). The 'gold standard' to perform FNAC is ultrasound guidance. Here, we analyze whether adding BRAF V600E-mutation analysis could be of value in palpation-guided FNACs. A total of 430 consecutive patients were included. Ultrasound-guided FNACs were performed in 251 patients and 179 patients underwent palpation-guided FNACs. BRAF V600E-mutation analysis was performed using two methods, an allele-specific polymerase chain reaction (PCR) analyzed by capillary gel electrophoresis (PCR/Qiaxcel), and a droplet digital PCR (ddPCR) assay. A total of 80 patients underwent surgery, and histology revealed 25 patients to have PTC. Of the 25 PTCs, 23 (92%) showed a BRAF V600E-mutation. Both mutation analysis methods (PCR/Qiaxcel and ddPCR) produced concordant results. In the ultrasound-guided group, the preoperative diagnostic sensitivity of FNAC using the Bethesda classification alone was very high and additional BRAF V600E-mutation analysis added little to the preoperative diagnostic sensitivity. By contrast, in the palpation-guided group, by adding BRAF V600E-mutation analysis, eight instead of four patients were diagnosed of having PTC. This increase in the diagnostic sensitivity was statistically significant (p < 0.05). The costs per sample were as low as 62 USD (PCR/Qiaxcel and ddPCR) and 35 USD (PCR/Qiaxcel only). Ultrasound-guided FNAC should be aimed for when dealing with thyroid nodules. However, if palpation-guided FNAC cannot be avoided or may be required due to resource utilization, adding BRAF V600E-mutation analysis using the methods described in this study might significantly increase the proportion of preoperatively diagnosed PTCs. The additional costs can be considered very reasonable.