Shipra Agarwal1, Andrey Bychkov2, Chan Kwon Jung3, Mitsuyoshi Hirokawa4, Chiung-Ru Lai5, SoonWon Hong6, Hyeong Ju Kwon6, Samreung Rangdaeng7, Zhiyan Liu8,9, Peng Su9, Kennichi Kakudo10, Deepali Jain1. 1. Department of Pathology, All India Institute of Medical Sciences, New Delhi, India. 2. Department of Pathology, Kameda Medical Center, Kamogawa, Chiba, Japan. 3. Department of Hospital Pathology, College of Medicine, The Catholic University of Korea, Seoul, South Korea. 4. Department of Diagnostic Pathology and Cytology, Kuma Hospital, Kobe, Japan. 5. Department of Pathology, Taipei Veterans General Hospital, Taipei, Taiwan. 6. Department of Pathology, Yonsei University, College of Medicine, Seoul, South Korea. 7. Department of Pathology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand. 8. Department of Pathology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Shandong, China. 9. Department of Pathology, Qilu Hospital of Shandong University, Shandong, China. 10. Department of Pathology, Nara Hospital, Kindai University Faculty of Medicine, Nara, Japan.
Abstract
BACKGROUND: Hürthle cell-rich nodules (HCNs) encompass non-neoplastic to malignant lesions. There is paucity of literature on the frequency distribution of HCNs among Bethesda categories, histologic follow-up, risk of malignancy (ROM), and risk of neoplasia (RON). The objective of this retrospective, multi-institutional study was to determine the prevalence of the cytologic diagnostic category and surgical outcomes of patients with HCN. METHODS: Nine tertiary health centers representing 6 Asian countries participated. Cases were retrieved from respective databases. The Bethesda System for Reporting Thyroid Cytopathology was used. Cytology results were correlated with surgical diagnoses. RESULTS: Of 42,190 thyroid aspirates retrieved, 760 (1.8%) had a Hürthle cell predominance. Most (61%) were categorized as atypia of undetermined significance/follicular lesion of undetermined significance, Hürthle cell type" (AUS-H); 35% were categorized as follicular neoplasm, Hürthle cell type (FN-H); and 4% were categorized as suspicious for malignancy (SFM). Histologic follow-up was available for 288 aspirates (38%). Most were benign on resection (66%), and the most common histologic diagnosis was Hürthle cell adenoma (28.5%). The ROM for AUS-H, FN-H, and SFM, as calculated on resected nodules, was 32%, 31%, and 71%, respectively; and the RON was 47%, 81%, and 77%, respectively. The 5 institutions that had an AUS-H:HCN ratio below 0.5 diagnosed HCN less frequently as AUS-H than as FN-H. CONCLUSIONS: This is the largest, contemporary, multi-institutional series of HCNs with surgical follow-up. Although there was wide interinstitutional variation in prevalence and surgical outcomes, there was no significant difference in the ROM among institutions. The categories AUS-H and FN-H had a similar ROM for resected nodules.
BACKGROUND: Hürthle cell-rich nodules (HCNs) encompass non-neoplastic to malignant lesions. There is paucity of literature on the frequency distribution of HCNs among Bethesda categories, histologic follow-up, risk of malignancy (ROM), and risk of neoplasia (RON). The objective of this retrospective, multi-institutional study was to determine the prevalence of the cytologic diagnostic category and surgical outcomes of patients with HCN. METHODS: Nine tertiary health centers representing 6 Asian countries participated. Cases were retrieved from respective databases. The Bethesda System for Reporting Thyroid Cytopathology was used. Cytology results were correlated with surgical diagnoses. RESULTS: Of 42,190 thyroid aspirates retrieved, 760 (1.8%) had a Hürthle cell predominance. Most (61%) were categorized as atypia of undetermined significance/follicular lesion of undetermined significance, Hürthle cell type" (AUS-H); 35% were categorized as follicular neoplasm, Hürthle cell type (FN-H); and 4% were categorized as suspicious for malignancy (SFM). Histologic follow-up was available for 288 aspirates (38%). Most were benign on resection (66%), and the most common histologic diagnosis was Hürthle cell adenoma (28.5%). The ROM for AUS-H, FN-H, and SFM, as calculated on resected nodules, was 32%, 31%, and 71%, respectively; and the RON was 47%, 81%, and 77%, respectively. The 5 institutions that had an AUS-H:HCN ratio below 0.5 diagnosed HCN less frequently as AUS-H than as FN-H. CONCLUSIONS: This is the largest, contemporary, multi-institutional series of HCNs with surgical follow-up. Although there was wide interinstitutional variation in prevalence and surgical outcomes, there was no significant difference in the ROM among institutions. The categories AUS-H and FN-H had a similar ROM for resected nodules.