Ultrasound guidelines developed by the American College of Radiology (ACR) can be trusted to accurately identify pediatric patients who should be biopsied for thyroid cancer, according to research presented on May 18 at the Society for Pediatric Radiology (SPR) meeting in Nashville, TN.
In addition to confirming the guidelines, the study shows that ultrasound is an effective tool for avoiding unnecessary biopsies in this patient population, said lead author Dr. Jennifer Lim-Dunham of Loyola University in Chicago in a statement released by the university.
Thyroid cancer is common in teenagers, and its occurrence is increasing -- although the reason why remains unclear. Adolescents have a tenfold greater incidence of the disease than younger children, and girls are diagnosed more often than boys.
Thyroid cancer is typically found during routine physical exams or on imaging tests such as CT that are conducted for other reasons. For a definitive diagnosis, the patient must undergo percutaneous fine-needle aspiration biopsy. However, because most nodules are benign, not all require biopsy, and ultrasound is a good way to determine whether a biopsy is really necessary.
Last year, the ACR published a grading system for thyroid nodules based on a 1 to 5 scale, with 1 being benign and 5 being highly suspicious of cancer. The scale takes into account ultrasound features of the thyroid nodule, such as its echogenicity, the quality of its edges (jagged or smooth), and whether it contains echogenic foci.
The researchers used this ACR system to grade 74 thyroid nodules in 62 pediatric patients. They found the system to be accurate and reproducible; in fact, for every one-unit increase in the scale, nodules were 2.63 times more likely to have a malignant diagnosis confirmed by biopsy or surgery.
The findings should provide reassurance of the ACR system's ability to differentiate between pediatric thyroid nodules that require biopsy and those that do not, Lim-Dunham concluded.
In a previous study, Lim-Dunham and colleagues found that a different set of thyroid nodule ultrasound guidelines from the American Thyroid Association are also trustworthy for evaluating the need for thyroid biopsy in children, the university said.
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
