What is the recurrence rate of thyroid cancer after hemisection?

The recurrence rate after a hemithyroidectomy for thyroid cancer cannot be generalized, as it varies among different pathological types of thyroid cancer patients. Clinically, thyroid cancer primarily includes papillary thyroid carcinoma, follicular thyroid carcinoma, medullary thyroid carcinoma, and anaplastic thyroid carcinoma.

1. Papillary Thyroid Carcinoma: This is the most common type of thyroid cancer with a relatively low malignancy. The 10-year disease-free survival rate for most patients is 98%, and the 10-year overall survival rate is 75%. This means that 80% of patients are unlikely to experience a recurrence after a hemithyroidectomy, resulting in a relatively low recurrence rate.
2. Follicular Thyroid Carcinoma: Prognosis is worse compared to papillary thyroid carcinoma, but the recurrence rate on the contralateral side and within the remaining thyroid tissue is still relatively low. About 20% of patients may experience recurrence within 10 years, and some may develop lymph node metastasis.
3. Medullary Thyroid Carcinoma: This malignancy arises from parafollicular cells of the thyroid and is relatively common. Cancer cells can secrete various amines and hormones, causing persistent diarrhea in some patients. The 5-year survival rate after surgical treatment for early-stage medullary thyroid carcinoma is 50%, and the 10-year survival rate is 20%.
4. Anaplastic Thyroid Carcinoma: This rare malignancy originates from thyroid follicular epithelium or parafollicular cells. Cancer cells can secrete various amines and hormones, leading to persistent diarrhea. In advanced stages, patients may experience metastasis to the lungs, bones, and other sites. Due to its rapid progression and poor prognosis, the recurrence rate after a hemithyroidectomy for anaplastic thyroid carcinoma is relatively high.

It is recommended that patients diagnosed with thyroid cancer undergo timely surgical treatment. Postoperatively, the need for adjuvant therapies such as radiation or chemotherapy should be determined based on pathological examination results to reduce the recurrence rate.