Thyroid Cancer in Primary Care: What's New from the 2025 ATA Guidelines
20 May 2026 · 3 min read · Last reviewed by Dr Jingyi Cao
Thyroid nodules are one of the most common findings in general practice - detectable by ultrasound in up to one in two adults. The vast majority are benign, but identifying the small proportion that represent thyroid cancer is essential. This article summarises the practical points from Dr Cao’s CPD session on thyroid cancer in primary care, including relevant updates from the 2025 ATA guidelines for differentiated thyroid cancer.
The numbers that matter
- Up to 1 in 2 adults has a thyroid nodule detectable on ultrasound - most are benign (American Thyroid Association)
- About 1 in 20 nodules is cancerous, and most thyroid cancers are highly treatable (American Thyroid Association)
- More than 3,000 Australians are diagnosed with thyroid cancer each year (Cancer Australia)
The clinical task in primary care is therefore not to find every nodule - it is to identify the small minority that deserve investigation.
Assessment in general practice
A focused history and examination comes first:
- History: voice change, swallowing difficulty, neck pressure or rapid swelling; growth of a known nodule over 6-12 months; family history of thyroid cancer
- Examination: nodule size and consistency, fixation, and cervical lymph nodes
- Bloods: thyroid function tests - a low TSH raises the possibility of a “hot” (functioning) nodule
- Ultrasound with structured reporting: suspicious features include microcalcifications, irregular margins, and a taller-than-wide shape
When to biopsy (FNA)
Fine-needle aspiration is the key diagnostic step. In line with ATA guidance, biopsy is typically considered for nodules around 1-1.5 cm or larger with suspicious ultrasound features - and for any nodule with concerning features regardless of size. If in doubt, early referral for assessment is always appropriate.
When to refer
Refer for specialist assessment when:
- Ultrasound or FNA features are suspicious
- A nodule is growing, or causes voice change, dysphagia or neck pressure
- The patient is younger, male, or has a family history of thyroid cancer
- There is any diagnostic uncertainty - a normal-feeling neck does not exclude deeper disease
What’s new from the 2025 ATA guidelines
The 2025 guidelines reinforce a risk-adapted approach to differentiated thyroid cancer:
- Surgery tailored to risk - hemithyroidectomy versus total thyroidectomy is now more clearly matched to tumour features and patient factors
- Active surveillance - for selected low-risk microcarcinomas, structured monitoring is a recognised alternative to immediate surgery
- Multidisciplinary decision-making remains central, with patients actively involved in the choice
The message for patients: many thyroid cancers are managed with a single, well-planned operation - and an increasing number of very low-risk tumours can be safely monitored rather than operated on at all.
What happens after referral
- We review the imaging and arrange ultrasound + FNA where indicated
- Consultation within 1-2 weeks at The SAN Clinic, Wahroonga
- A clear plan: surveillance with defined intervals, or surgery (hemi vs total thyroidectomy) - and written feedback to the referring GP
This article is based on Dr Cao’s session in the CPD course Emerging Oncology Insights for General Practice, presented with Sydney Adventist Hospital. The advice here is of a general nature and is not a substitute for individual medical advice.