From the Guidelines
The next steps for a marked enlargement of the left thyroid lobe with contour irregularity should include a referral to an endocrinologist and a fine-needle aspiration biopsy (FNAB) of the enlarged left lobe, as recommended by the most recent guidelines 1.
Key Considerations
- The significant size discrepancy between the lobes (left lobe 4.2 x 8.1 x 3.8 cm versus right lobe 1.8 x 4.5 x 2.8 cm) along with heterogeneity and contour irregularity raises concern for potential malignancy, even without a discrete nodule.
- Blood tests should be ordered to assess thyroid function, including TSH, free T4, free T3, thyroid antibodies (anti-TPO and anti-thyroglobulin), and calcitonin levels, as suggested by the guidelines 1.
- Additional imaging with a radioiodine scan may help determine if the enlargement is functioning or non-functioning tissue, as mentioned in the guidelines 1.
- The patient should be monitored for compressive symptoms such as difficulty swallowing, voice changes, or breathing problems that might indicate a need for more urgent intervention.
Diagnostic Approach
- Thyroid ultrasound (US) supplemented by fine needle aspiration cytology (FNAC) should be used as a first-line diagnostic procedure for detecting and characterizing nodular thyroid disease, as recommended by the guidelines 1.
- Serum calcitonin (CT) is a reliable tool for the diagnosis of medullary thyroid cancer and its measurement should be an integral part of the diagnostic evaluation of thyroid nodules, as suggested by the guidelines 1.
Treatment and Follow-up
- The treatment and follow-up of thyroid cancer should be based on the guidelines, which recommend total or near-total thyroidectomy as the initial treatment, followed by radioiodine ablation and TSH suppressive therapy with L-T4, as mentioned in the guidelines 1.
- The patient should be followed up regularly with physical examination, neck US, and basal and rhTSH-stimulated serum thyroglobulin measurement to check for recurrence or metastasis, as recommended by the guidelines 1.
From the Research
Next Steps for Patient with Enlarged Left Thyroid Lobe
The patient's condition, characterized by marked enlargement of the left thyroid lobe, heterogeneous texture, and contour irregularity, but no dominant thyroid nodule, requires further evaluation. The left lobe measures 4.2 x 8.1 x 3.8 cm and the right lobe measures 1.8 x 4.5 x 2.8 cm.
Diagnostic Approach
- Fine-needle aspiration biopsy (FNA) is the most reliable and cost-effective method for distinguishing benign from suspicious or malignant thyroid nodules 2, 3, 4.
- The approach to the management of patients with thyroid nodules should include FNA biopsy, as it has the greatest diagnostic accuracy, approaching 95% 2, 4.
- Ultrasound-guided FNA biopsy is recommended, especially in cases where the nodule is nonpalpable or part of a multinodular goiter, as it improves the accuracy of the biopsy 5.
Interpretation of FNA Biopsy Results
- The Bethesda System for Reporting Thyroid Cytopathology categorizes thyroid cytology findings into six groups, with each group assigned a putative malignancy risk 6.
- A working knowledge of the Bethesda System permits accurate, evidence-based risk stratification of patients with thyroid nodules and facilitates their management 6.
- The results of the FNA biopsy will guide further management, including the possibility of surgical excision if malignant cells are detected 2, 3, 4.
Considerations
- The patient's clinical features, such as the size and characteristics of the thyroid lobes, should be taken into account when interpreting the FNA biopsy results 2, 3.
- The presence of a heterogeneous texture and contour irregularity in the left thyroid lobe may increase the likelihood of malignant involvement, but the absence of these features does not exclude the possibility of cancer 2, 3.