Core needle biopsy: an efficacious adjunct to cytological diagnosis in thyroid tumours suspected of anaplastic carcinoma - single-centre experience

Introduction: Ultrasound-guided fine- needle aspiration biopsy (FNAB) remains the primary method for diagnosing thyroid nodules, providing adequate information for definitive diagnosis and treatment decisions in most cases. However, cytological examinations sometimes yield inconclusive or non-diagnostic results. For rapidly growing tumours with suspected malignancy, a swift and accurate diagnosis is crucial to initiate timely treatment. Cases suggestive of anaplastic thyroid cancer (ATC) or poorly differentiated cancer present unique challenges in obtaining satisfactory diagnostic material through FNAB, due to advanced necrosis or extensive inflammatory components. In these instances, core needle biopsy (CNB) emerges as a complementary diagnostic tool when FNAB results are ambiguous. This study aimed to evaluate the effectiveness of CNB in diagnosing rapidly growing thyroid tumours with clinical indication of ATC.

Material and methods: Between 2019-2023, 31 CNBs were performed on large, rapidly expanding thyroid tumours.

Results: All cases exhibited clinical signs of malignancy, with previous FNAB outcomes being either equivocal or inconclusive. The subsequent CNBs demonstrated accurate results with minimal complications among the patients. While reservations about CNB for thyroid nodules persist, it offers a valuable diagnostic alternative, potentially preventing unwarranted surgical biopsy or removal of the thyroid.

Conclusions: Core needle biopsy deployment should be judicious, reserved for select cases, and carried out in a hospital environment to ensure diagnostic precision with the least risk of complications.