Annals of Surgical Oncology

, Volume 25, Issue 13, pp 3913–3918 | Cite as

Both Ultrasound Features and Nuclear Atypia are Associated with Malignancy in Thyroid Nodules with Atypia of Undetermined Significance

  • Naseem Eisa
  • Ahsan Khan
  • Mutaal Akhter
  • Molly Fensterwald
  • Saba Saleem
  • Ghaneh Fananapazir
  • Michael J. CampbellEmail author
Endocrine Tumors



The optimal management of thyroid nodules that undergo fine-needle aspiration (FNA) with findings of atypia of undetermined significance (AUS) is unclear. Categorizing nodules by AUS subtype and ultrasound characteristics may improve risk stratification. Therefore, the purpose of this study is to evaluate the association between AUS subtype and ultrasound features on risk of malignancy (ROM).


We performed a review of all patients with a thyroid nodule who underwent an FNA at our institution between January 2010 and November 2015. Patients with AUS were divided into groups with (1) nuclear atypia, (2) architectural atypia, or (3) Hurthle cell atypia. Their ultrasound features were assessed using the American Thyroid Association (ATA) thyroid nodule sonographic patterns. We conducted a univariate and multivariable analysis to determine the association between AUS subtype and other variables of interest with ROM.


Of the 3428 thyroid nodules that underwent FNA, 237 (6.9%) had AUS. Of the 97 surgically resected nodules, 67 (69%) were benign and 30 (31%) were malignant. On univariate analysis nuclear atypia (p < 0.01) was associated with a thyroid malignancy. On multivariable analysis, both ATA high-risk ultrasound features (p = 0.04, odds ratio [OR] 3.68) and nuclear atypia (p < 0.01, OR 11.8) were independently associated with a final diagnosis of thyroid carcinoma.


Nuclear atypia and ATA high-risk ultrasound features are useful in identifying patients with AUS that are at a higher risk of thyroid malignancy. Surgeons should take these factors into consideration when evaluating patients with AUS.



The authors thank Dr. Alison Semrad and Dr. Kent Ishihara for their help reviewing and providing critical feedback on this manuscript. We would also like to thank Dr. Sandra Taylor for statistical assistance.


Department funds were used for incidental expenses.


The authors have no conflicts of interest to disclose.


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Copyright information

© Society of Surgical Oncology 2018

Authors and Affiliations

  • Naseem Eisa
    • 1
  • Ahsan Khan
    • 2
  • Mutaal Akhter
    • 2
  • Molly Fensterwald
    • 2
  • Saba Saleem
    • 2
  • Ghaneh Fananapazir
    • 3
  • Michael J. Campbell
    • 4
    • 5
    Email author
  1. 1.Department of Internal MedicineUniversity of California, Davis Medical CenterSacramentoUSA
  2. 2.School of MedicineUniversity of California, Davis Medical CenterSacramentoUSA
  3. 3.Department of RadiologyUniversity of California, Davis Medical CenterSacramentoUSA
  4. 4.Department of SurgeryUniversity of California, Davis Medical CenterSacramentoUSA
  5. 5.University of California, Davis, Comprehensive Cancer CenterSacramentoUSA

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