Can papillary thyroid cancer be
treated by hemithyroidectomy alone?
Dr Tuttle presented the latest revision of the American Thyroid Association (ATA) guidelines for thyroid cancer to the Noosa Thyroid meeting. The guidelines cover all aspects of the investigation and management of thyroid cancer in over 400 pages. One of the more controversial changes relates to the question of whether thyroid cancer can be treated by hemithyroidectomy (or lobectomy) alone. Recommendation 35 of the guidelines states that large tumours >4cm still require total thyroidectomy, small tumours <1cm are adequately treated by hemithyroidectomy, and for intermediate sized cancers the best procedure is a matter of judgement and informed discussion between patient and surgeon. The advantages of a hemithyroidectomy are a reduced exposure to potential complications and the avoidance of lifelong thyroxine therapy, whereas the advantages of total thyroidectomy are a reduced risk of local recurrence of the cancer and an assurance of disease-free status by testing for thyroglobulin levels. The evidence is clear that there is no difference in long term survival in this situation between total thyroidectomy and hemithyroidectomy, however significantly more patients having a hemithyroidectomy will require further follow-up surgery to deal with locally recurrent disease.
A) For patients with thyroid cancer >4 cm, or with gross extrathyroidal extension
(clinical T4), or clinically apparent metastatic disease to nodes (clinical N1) or distant sites
(clinical M1), the initial surgical procedure should include a near-total or total thyroidectomy and
gross removal of all primary tumor unless there are contraindications to this procedure. (Strong
Recommendation, Moderate-quality evidence)
B) For patients with thyroid cancer >1 cm and <4 cm without extrathyroidal extension,
and without clinical evidence of any lymph node metastases (cN0), the initial surgical procedure
can be either a bilateral procedure (near-total or total thyroidectomy) or a unilateral procedure
(lobectomy). Thyroid lobectomy alone may be sufficient initial treatment for low risk papillary
and follicular carcinomas; however, the treatment team may choose total thyroidectomy to
enable RAI therapy or to enhance follow-up based upon disease features and/or patient
preferences. (Strong Recommendation, Moderate-quality evidence)
C) If surgery is chosen for patients with thyroid cancer <1 cm without extrathyroidal
extension and cN0, the initial surgical procedure should be a thyroid lobectomy unless there are
clear indications to remove the contralateral lobe. Thyroid lobectomy alone is sufficient
treatment for small, unifocal, intrathyroidal carcinomas in the absence of prior head and neck
irradiation, familial thyroid carcinoma, or clinically detectable cervical nodal metastases.
(Strong Recommendation, Moderate-quality evidence)