Thyroid Cancer Detected by Mass Screening Over a Period of 16 Years at a Health Care Center in Japan

Abstract

Manipulation is adequate as an initial screening method for thyroid examination, and ultrasonography may not always be required. Moreover, it is necessary to consider gender when referring a patient to a specialist and when deciding on the indications for surgery to remove a thyroid tumor.

Prognostic parameters for recurrence of papillary thyroid microcarcinoma

“…A smaller proportion of these tumors is detected during imaging of the neck for other purposes, such as parathyroid evaluation, using (for example) carotid Doppler, CT, and FDG-PET. In Korea and Japan, however, many health care centers perform ultrasonography during initial examination of the thyroid [ 5 - 7 ], and impalpable nodules have increasingly been discovered. Korea is a country without iodine deficiency [ 17 ] and many thyroids have only one nodule, making ultrasound an excellent method to detect PTMCs.…”

“…Most PTMCs are incidentally detected by histological analysis of thyroid glands removed for preoperatively diagnosed benign diseases, or are indirectly diagnosed because of the presence of enlarged metastatic cervical lymph nodes or distant metastases [ 3 , 4 ]. In Korea and Japan, however, where ultrasonography is frequently used in the initial examination of thyroid glands [ 5 - 7 ], the incidence of PTMC has increased explosively [ 8 ].…”

Introducing the reporting system for thyroid fine-needle aspiration cytology according to the new guidelines of the Japan Thyroid Association [Review]

“…It includes cases with equivocal features of PTC (Fig. 3), features suggestive of chronic thyroiditis and malig- ciently select patients with thyroid nodules for surgery because the risk of malignancy of follicular neoplasm was within the range of baseline risk of malignancy, which was estimated to be about 10-20% in Western countries and 12.4-15.9% in Japan [6,7,[37][38][39][40]. Among a series of 1044 surgically treated patients at Kuma Hospital, Kobe, Japan, in 2000, Mori et al reported that the risk of FTC was 7.9% (22/279) in cases with nodular thyroid diseases (other types of malignancy were excluded) and incidental PTC was found in 7.2% (20/277) of patients with benign nodular disease, with the total risk of malignancy (risk of FTC in index nodule and risk of incidental PTC) in patients with a thyroid nodule (other types of malignancy were excluded) being 14.0% (42/299) [39].…”

Quantitative Assessment of Thyroid Nodules Using Dual-Energy Computed Tomography: Iodine Concentration Measurement and Multiparametric Texture Analysis for Differentiating between Malignant and Benign Lesions

“…ROIs were drawn to include as much of the lesions, whilst avoiding cysts and overt calcifications. e following quantitative parameters were measured: [1] iodine concentration (mg/mL) at 120 kVp and [2] CT attenuation curve slope, plotted from 40 keV to 190 keV ( Figure 1).…”

“…yroid nodules are found with increasing frequency, likely due to the widespread use of imaging modalities including ultrasonography (US) and computed tomography (CT). Although more than 95% of the detected nodules are clinically insignificant benign lesions, thyroid nodules are clinically important as they may represent thyroid malignant tumor [1,2]. Despite an increase in the prevalence of malignant thyroid nodules and invasive examinations, the mortality rate has remained unchanged from 1973; this observation is attributed to overdiagnosis of subclinical thyroid nodules [3,4].…”