TY - JOUR AU - Miyauchi, Akira AB - Background: There is little information regarding the natural course of hypoechoic thyroid lesions that are probable or possible thyroid lymphoma based on fine needle aspiration cytology (FNAC) results. Methods: Sixty-five patients who were diagnosed as probable or possible thyroid lymphoma by ultrasonography (US) and FNAC were investigated. Forty-three patients with strong suspicion underwent thyroid surgery for the diagnosis at our hospital, and 22 patients were followed up with periodic US examination. Thyroid lymphoma was definitely diagnosed in 41 out of 43 patients who underwent thyroid surgery, and such patients were defined as Group A. The outcomes of 22 patients who were followed up without an immediate therapy were analyzed. Their hypoechoic lesions decreased in size (n = 10) or disappeared (n = 2) in 12 of 22 patients, and such patients were defined as Group B. Patients in Group A and B were compared using the Kuma Hospital-US classification (USC), the diagnostic categories of the Bethesda System for Reporting Thyroid Cytopathology, and the κ/λ deviation of the immunoglobulin light chain in the FNAC specimens. Mann-Whitney U-test and chi-squared test (with Yate’s continuity correction) were used to compare the two groups. Results: The USC of < 3.5 [9/12 (75.0%) in TI - Characteristics and natural course of hypoechoic thyroid lesions diagnosed as possible thyroid lymphomas by fine needle aspiration cytology JF - Thyroid Research DO - 10.1186/s13044-018-0051-z DA - 2018-05-30 UR - https://www.deepdyve.com/lp/springer-journals/characteristics-and-natural-course-of-hypoechoic-thyroid-lesions-AbTryJUJLR SP - 1 EP - 8 VL - 11 IS - 1 DP - DeepDyve ER -