Hurthle cell thyroid cancer is a rare cancer that affects the thyroid gland. About 3% to 4% of thyroid cancers are diagnosed as hurthle cell cancer. Considered to be a variant of follicular cell cancer, it is also called hurthle cell carcinoma or oxyphilic cell carcinoma.
The butterfly-shaped thyroid gland has two types of cells:
- follicular cells, which secrete the thyroid hormone that is important for metabolism along with many other functions, and
- parafollicular cells, which secrete calcitonin that is responsible for regulating calcium levels in the blood (by decreasing them).
The hurthle cell neoplasms — the mass of tissue formed when the cells divide abnormally (more than they should) — originate from the follicular cells of the thyroid gland.
“The name hurthle cell comes from the microscopic finding of large cells with a few typical features like abundant eosinophilic cytoplasm and a large hyperchromatic nucleus with prominent nucleoli,” says Dr Soumya Somasekar, a surgical oncologist at Bengaluru’s Ramaiah Hospital.
Hurthle cell thyroid cancer symptoms and prognosis
According to a recent review article, there is no specific cause for this type of cancer. But if the individual has been exposed to radiation in the head, neck and chest region, or if there is a family history of thyroid cancer, then the risk of getting it is high.
“The individual feels a lump — which is usually painless — in front of the neck at the region of the thyroid gland (midline),” says Dr Somasekar. “In advanced cases, there might be a change in the person’s voice or difficulty in breathing or swallowing and pain due to the presence of the large tumor.”
The tumors can be both benign and malignant. If they are benign, they don’t spread to other parts of the body.
“If the hurthle cell tumor is malignant or cancerous, it can spread by the lymphatic vessels to the lymph nodes and through blood vessels to the lungs, bones or liver,” adds Dr Somasekar.
The tumors can create a lot of complications if they invade the larynx, vocal cords, trachea or esophagus, since this can lead to compression of major nerves and vessels in the neck.
Hurthle cell thyroid cancer prognosis has a higher rate of metastases (the spread of the cancer cells to the other parts). The overall survival rate is also lower compared to follicular thyroid carcinoma. Hence it is considered to be more aggressive.
Hurthle cell thyroid cancer: diagnosis and treatment
This type of thyroid cancer is more common in women (almost four times more common than in men) in ages 50 to 60 years. At times, it is chanced upon when undergoing an ultrasound or CT scan for a different purpose.
“The diagnosis before the surgery is difficult, but FNAC (fine needle aspiration cytology) or FNAB (fine needle aspiration biopsy) tests — which use a small needle to take sample of neck swelling — can suggest a possibility of this type of tumor,” says Dr Somasekar.
Confirmatory diagnosis is done by removing the full tumor by surgery and examining it.
The hurthle cell carcinoma treatment is done by total thyroidectomy (surgical removal of the thyroid gland), the most common surgery. The lymph nodes in the neck are removed if they are involved.
“After surgery, radio-iodine treatment can be given in instances where the risk of a relapse is high, or if there is evidence of the spread of cancer outside the gland,” she adds.
After thyroidectomy, the natural supply of thyroid hormone to the body is no longer available, hence thyroxine pills are to be taken.
Takeaways
- Hurthle cell thyroid cancer is a rare type of thyroid cancer, representing 3% to 4% of all thyroid cancer cases.
- The tumors can be both benign and malignant.
- One of the major symptoms of hurthle cell thyroid cancer is a swelling or lump in the neck. The swelling is initially painless but can cause immense pain in the advance stages.
- The most common treatment involves total thyroidectomy.
