Association of ultrasonographically determined anatomical location of Bethesda 3 thyroid nodules with differentiated thyroid cancer

Emre Gezer; Halil Demirkan; Zeynep Cantürk; Alev Selek; Berrin Çetinarslan; Mehmet Sözen; Mustafa Çalis Kan; Alper Çağrı Karci; Tevhide Bilgen Özcan; Ömercan Topaloğlu; Büs Ra Yaprak Bayrak; Özge Demirkol

doi:10.5339/qmj.2022.51

Association of ultrasonographically determined anatomical location of Bethesda 3 thyroid nodules with differentiated thyroid cancer

Qatar Med J. 2022 Nov 14;2022(4):51. doi: 10.5339/qmj.2022.51. eCollection 2022.

Affiliations

¹ Faculty of Medicine, Kocaeli University, Department of Endocrinology and Metabolism, Kocaeli, Turkey Email & ORCID ID: gezer_emre@hotmail.com & https://orcid.org/0000-0002-5340-6106.
² Adatip Hospitals, Division of Endocrinology and Metabolism, Sakarya, Turkey.
³ Duzce Ataturk State Hospital, Division of Endocrinology and Metabolism, Duzce, Turkey.
⁴ Bağcılar Training and Research Hospital, Department of Endocrinology and Metabolism, Istanbul, Turkey.
⁵ Bağcılar Training and Research Hospital, Department of Pathology, Istanbul, Turkey.
⁶ Zonguldak Bulent Ecevit University, Department of Endocrinology and Metabolism, Zonguldak, Turkey.
⁷ Faculty of Medicine, Kocaeli University, Department of Pathology, Kocaeli, Turkey.

Abstract

Background: The size of a thyroid nodule and certain sonographic features, such as marked hypoechogenicity, microcalcifications, taller-than-wide shape, microlobulated, or irregular margins, indicate the greater malignancy risk. The frequency of the atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) category among cytology reports from thyroid fine-needle aspirations ranges from 0.8% to 28%, whereas the risk of malignancy of these nodules varies from 6% to 97%. This retrospective analysis investigated whether the preoperative ultrasonographic location of Bethesda 3 thyroid nodules is a predictive risk factor for differentiated thyroid cancer (DTC).

Methods: A total of 387 patients who underwent total thyroidectomy for a nodule with AUS/FLUS cytology and diagnosed with a DTC at five tertiary referral centers between 2010 and 2020 were retrospectively analyzed. The location of the thyroid nodule with AUS/FLUS cytology was categorized into two groups: one group was composed of the isthmus, upper lobe, middle lobe, and lower lobe, whereas the latter consisted of right lobe, left lobe, and isthmus.

Results: DTC was diagnosed in 40.6% (n = 157) of the operated nodules. Multiple logistic regression analysis has revealed that hypoechogenicity of the nodule (odds ratio [OR] = 2.929, p < 0.001) was the only independent predictive factor for the malignancy of the nodules with AUS/FLUS, whereas the location of the nodule, age, and sex were not significantly independent risk factors. Multifocality and contralateral benign nodules were independent predictive factors for multicentricity (OR = 3.5, p = 0.002; OR = 5.5, p = 0.001, respectively).

Conclusion: As the first study investigating the association between a Bethesda 3 nodule location and the risk of malignancy by evaluating postoperative cytology reports, the results showed that nodule location with AUS/FLUS on fine-needle aspiration biopsy was not a predictive risk factor for the diagnosis of DTC.

Keywords: Aspiration biopsy; cytopathology; fine-needle; location; papillary thyroid carcinoma; thyroid nodule; ultrasonographic imaging; undetermined significance.