The McGill Thyroid Nodule Score’s (MTNS+) role in the investigation of thyroid nodules with benign ultrasound guided fine needle aspiration biopsies: a retrospective review

Abstract

BackgroundUltrasound guided fine needle aspiration (USFNA) biopsies of thyroid nodules sometimes create a decision-making dilemma for surgeons as they may yield falsely benign results. The McGill Thyroid Nodule Score + (MTNS+) was developed to aid in clinical guidance regarding the management of patients with these USFNA results. The aim of this study was to assess the MTNS+ as a clinical tool in patients with benign preoperative thyroid nodule USFNAs and to analyze the relationship between nodule size and malignancy in these patients.MethodsWe conducted a retrospective chart review of 1312 patients who underwent thyroidectomies between 2010 and 2015 at the McGill University Teaching Hospitals. Patients with Bethesda II (benign) USFNA results, calculated MTNS+, and nodule size evaluated on ultrasound were included in the study. The false-negative rate was calculated, and MTNS+ and nodule size were each compared to final pathology results. Binary logistic regression was used for statistical analysis.ResultsOf the 1312 patients, 101 met the inclusion criteria and together had an average MTNS+ score of 6.83, which corresponds to a predicted malignancy rate between 25 and 33 %. Final pathology revealed malignancy in 16 (15.8 %) subjects. The average MTNS+ of patients with malignant nodules on surgical pathology was 8.25, while that of patients with benign nodules was 6.56.Patients with nodule size 1–1.9 cm (a) and 2–2.9 cm (b) each had an equal rate of malignancy of 2.97 % (n = 3), nodule size 3–3.9 cm (c) had a rate of 1.98 % (n = 2), and nodule size ≥4 cm (d) a rate of 7.92 % (n = 8).ConclusionThe rate of malignancy (15.8 %) is higher than expected when reviewing the risk of malignancy in nodules considered as Bethesda class 2. On the other hand, the rate is lower than the 25–33 % predicted by the MTNS+. We also found a higher malignancy rate for nodules above 4 cm in size, but size was a poor predictor of malignancy when used alone. Therefore, while the MTNS+ may be helpful at helping to identify USFNAs that are incorrectly classified as benign, the percentage risk of malignancy is lower than expected.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

“…A retrospective study including 3297 patients with proven PTC found the highest odds ratio for malignancy (41-53) in patients with malignant and suspicious for malignancy FNA results, compared with 9 for high risk ultrasound features and 13 for the BRAF mutation. A nomogram that incorporates these variables into a more precise cancer estimate was proposed; similar models are available 113182183184185186187188. A study using the K-TIRADS classification and the FNA cytology result confirmed the expected relation between pre-test probability of malignancy based on ultrasound and FNA result.…”

Increased Chromosomal and Oxidative DNA Damage in Patients with Multinodular Goiter and Their Association with Cancer

“…However, it is clear that thyroid nodule size on ultrasound is a poor predictor of malignancy when used alone for the assessment and management of thyroid nodules [37]. …”

Malignancy Rate and Reliability of Cytology in Operated Giant Thyroid Nodules

“…Bizim çalışmamızda opere edilen dev nodüllerde malignite oranı %14,40 bulunmuştur. Çalışmaların büyük bir kısmında dev nodüllerde malignite oranı daha küçük çaptaki nodüllere benzer bulunurken, [12][13][14] bir kısmında daha düşük 15,16 bir kısmında ise daha fazla olarak raporlanmıştır. 17,18 Yakın zamanda yapılmış 14 çalışmanın ele alındığı bir meta analizde <4 cm 16778 hastada malignite oranı ≥ 4 cm 4660 hasta ile karşılaştırıldığında anlamlı farklılık saptanmamıştır (%19'a karşılık 20,9 p =0,87 %5 CI 0,62-1,22 Bizim çalışmamızda ultrasonografik özellikler benign ve malignnodüllerde benzer çıkmıştır.…”