Thyroideakræft

Thyroideakræft, also known as thyroid cancer, is a malignant neoplasm arising from the follicular cells of the thyroid gland. It constitutes a small proportion of all cancers worldwide, yet it is the most common endocrine malignancy. Incidence rates vary geographically; high prevalence is reported in iodine‑deficient regions and among populations with increased exposure to radiation of the neck. In Denmark, the annual incidence is around 3 to 4 per 100 000, with a slight female predominance.

The disease is classified into several histological subtypes. Papillary carcinoma represents the majority and is generally indolent with excellent long‑term survival. Follicular carcinoma, medullary carcinoma, and anaplastic carcinoma are less common and have more variable prognoses. Risk factors include age, gender, family history, genetic syndromes such as Multiple Endocrine Neoplasia type 2, and a history of ionising radiation, particularly during childhood.

Clinical presentation often includes a painless neck mass, compressive symptoms such as dysphagia or hoarseness, and occasionally dysphonia. Radio‑active iodine uptake, thyroid ultrasound, fine‑needle aspiration biopsy, and laboratory evaluation of thyroid function and calcitonin are standard diagnostic tools. Staging incorporates the TNM classification based on tumour size, local invasion, lymph node involvement, and distant metastasis.

Therapeutic approaches depend on subtype, stage and patient factors. Standard treatment for papillary and follicular tumours generally involves total or near‑total thyroidectomy, followed by radioactive iodine ablation in selected cases. Medullary carcinoma is typically managed surgically with lymph node dissection, while anaplastic carcinoma often requires multimodal care including surgery, external beam radiotherapy and chemotherapy, though prognosis remains poor. Endocrine therapy with levothyroxine suppressive therapy and TSH monitoring is standard after surgery for differentiated thyroid cancer. Prognosis is highly favourable in well‑differentiated disease, with 5‑year survival rates exceeding 90 % in early stages, whereas anaplastic carcinoma has a median survival of a few months. Ongoing research focuses on targeted therapies, genetic profiling and improved surveillance protocols.