Preoperative Diagnosis of Thyroid Follicular Tumor

doi:10.37015/AUDT.2024.240014

Abstract

Abstract:

The incidence rate of follicular thyroid carcinoma ranks second among thyroid malignancies. Compared to papillary thyroid carcinoma, it has higher rates of recurrence and metastasis, making it a threat to a patient's health. Unfortunately, accurately diagnosing follicular tumors before surgery remains an unresolved issue, as this type of disease is a gray area of fine-needle aspiration biopsy and can be challenging to differentiate clinically from benign thyroid follicular tumors. There are many studies have focused on the preoperative diagnosis of follicular tumors, and much progress has been made. However, according to current research, postoperative biopsies are still the only definitive ways to diagnose follicular thyroid carcinoma, providing evidence of capsule and vascular infiltration. We must emphasize the importance of early detection and diagnosis of follicular thyroid carcinoma to ensure effective treatment and recovery. This review provides a comprehensive summary of the literature on follicular thyroid carcinoma, including its epidemiology, clinical features, imaging diagnosis, genetic and molecular testing of thyroid follicular carcinoma, and a detailed description of the preoperative diagnosis of follicular thyroid carcinoma. We urge medical professionals to use this information to improve their understanding of this disease and enhance their ability to accurately diagnose and treat it.

Key words: Thyroid follicular tumor; Preoperative diagnosis; Fine-needle aspiration biopsy; Molecular diagnosis; Ultrasound

Ye Beibei, Zhang Yifeng. Preoperative Diagnosis of Thyroid Follicular Tumor. Advanced Ultrasound in Diagnosis and Therapy, 2025, 9(2): 127-137.

Figures/Tables 6

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References 100

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Characteristic	Follicular thyroid carcinoma	Follicular thyroid adenoma
Composition	Predominantly solid [30]	Solid or mixed cystic and solid [23]
Echogenicity	Predominantly Hypoechoic [23,24]	Iso or Hypoechoic [23]
Echo texture	Heterogeneous [30]	Predominantly homogeneous [23]
Margin	Irregular or extra thyroidal extension [24]	Smooth [25]
Peripheral halo	Incomplete/unevenly thick [23]	Present and thin [23]
Vascularity	Rich internal flow [35,36]	Peripheral flow [35]
Metastasis	Hematogenous/lymphatic metastasis [15,25]	No metastasis [25]
Vascular and capsule	Invasion [4]	No invasion [26]

Characteristic	Follicular thyroid carcinoma	Papillary thyroid carcinoma
Maximum diameter	Large diameter, mostly > 4 cm [21,26]	Small diameter, mostly < 2 cm, predominantly in PTMC [19]
Composition	Predominantly solid [30]	Predominantly solid [30]
Echogenicity	Predominantly Hypoechoic [24]	Hypo or markedly Hypoechoic [19]
Shape	Wider than tall [24]	Taller than wide [19]
Margin	Irregular or extra thyroidal extension [24]	Lobulated or irregular or extra thyroidal extension [24]
Calcification	Macrocalcifications [27,34]	Punctate echogenic foci [32,33]
Peripheral halo	Incomplete/unevenly thick [23]	No peripheral halo [96]
Vascularity	Rich internal flow [35,36]	Atypical flow presentation [95]
Metastasis	Hematogenous/lymphatic metastasis [15]	Cervical lymphatic metastasis [94]
BRAF V600E tests	Negative [93]	Positive (60%~80%) [92,100]
Pathology	Vascular and capsule invasion [74]	Papillary features, glass changes in nucleus, psammoma bodies [74]

Characteristic	Follicular thyroid carcinoma	Follicular thyroid adenoma	Papillary thyroid carcin oma
Boundary of the enhanced lesions	Ill-defined [45]	Well-defined, ring-enhancement [100]	Ill-defined [100]
Enhancement homogeneity	Heterogeneous [45]	Heterogeneous/Homogeneous [98]	Heterogeneous [98]
Size of the enhanced lesions	Lager than grey scale image [46]	Similar to grey scale image size [97]	Smaller than grey scale image [95]
Enhancement degree	Hyper-/iso-enhancement [46]	Hyperenhancement [100]	Hypo/iso-enhancement [99]
Enhancment direction	Centrifugal [45]	Centripetal [98]	Centripetal [84]