In an interview with <em>Targeted Oncology</em>, Dr. Miles, discussed the importance of early detection for patients with thyroid cancer. He also highlighted how the treatment options differ for patients with disease that is caught early on versus those with more advanced and aggressive diseases, such as anaplastic thyroid cancer.<br />
Brett A. Miles, DDS, MD
Primary treatment for patients with early-stage thyroid cancer is generally surgical resection. According to Brett A. Miles, DDS, MD, the 5-year survival rate for thyroid cancers that are caught and treated early with surgery is around 98%, demonstrating the importance of diagnosing patients in the early stages of the disease. Thyroid cancer is the cause of less than 1% of all cancer deaths, making this a very low-risk disease when caught early.
For patients that are diagnosed with advanced thyroid cancer, it is common for these cancers to spread to the lymph nodes or to other distant areas, such as the lungs. Surgical resection can still be an option for these patients, but surgical management can become more complicated after the disease has spread. Following upfront surgery, other treatment options in this setting include radioactive iodine or occasionally external radiation therapy or chemotherapy.
Thyroid cancer is most commonly diagnosed by ultrasound when a lump is found in the neck. However, other methods of diagnosis include MRI, CT scans, or biopsies. Because of the high cure rate in patients with thyroid cancer, it is emphasized that patients should be diagnosed immediately when any lumps arise on the neck or thyroid region, or if any thyroid masses are noted on routine scans which were obtained for other reasons.
Additionally, patients should be checked for a number of common mutations found in thyroid cancer, including theBRAFV600E mutation, as well asRAS,PTEN, andTERT. Patients harboring these genetic alterations may be at higher risk and in advanced cases treatment with any of the investigational targeted therapies or immunotherapies available in clinical trials or that are already FDA approved may be an option.
In an interview withTargeted Oncology, Miles, professor of otolaryngology head and neck surgery and co-chief of the Division Head and Neck Oncology at Mount Sinai, discussed the importance of early detection for patients with thyroid cancer. He also highlighted how the treatment options differ for patients with disease that is caught early on versus those with more advanced and aggressive diseases, such as anaplastic thyroid cancer (ATC).
TARGETED ONCOLOGY: How do treatment options for patients with thyroid cancer that are diagnosed earlier on versus later in the development of the disease?
Miles:The primary treatment for the majority of thyroid cancers, especially early, is surgery, to remove the thyroid cancer. I would note that there are several types of thyroid cancer, some of which are higher risk, but the majority of thyroid cancers, called well-differentiated thyroid cancers, have a very excellent prognosis when caught early and treated. Treatment is surgical removal of the thyroid gland and any associated lymph nodes that are involved with the thyroid cancer. The 5-year survival rate for those types of cancer is around 98%. If treated early with surgery, the majority of thyroid cancers have an excellent survival. Out of about 52,000 new cases, the number of deaths is very low, probably less than 1% of all cancer deaths are related to thyroid cancer, so there is a very low risk of dying from this disease, with the exception of a few rare types of thyroid cancer.
In terms of advanced thyroid cancers, depending on the type, these cancers often spread to lymph nodes in the neck or spread distantly, most commonly to the lungs, but certainly many of them can be treated effectively. The more aggressive types can also invade structures in the neck, and if they’re caught at later stages, it may complicate the surgical management. Occasionally, those patients will need additional treatment, such as radiation and chemotherapy.
TARGETED ONCOLOGY: What other treatment options are available for patients with more advanced disease?
Miles:For advanced thyroid cancers, it depends on the type of thyroid cancer as far as what the treatment options are. Generally, surgery will be recommended upfront if the thyroid cancer is resectable. After surgery, a variety of treatments may be indicated. One of these treatments is called radioactive iodine therapy, which is a single-dose radioactive iodine pill that is designed to kill any remaining thyroid cancer cells in the body after surgery. Second, for more aggressive cancers, we occasionally use external radiation treatment. Occasionally, some other types of therapy such as chemotherapy, targeted therapy, or immunotherapy are used for very advanced thyroid cancers; however, those are the rare types. The majority of thyroid cancers are treated upfront with surgery and do quite well and do not require any other systemic therapy.
TARGETED ONCOLOGY: Can you speak more to the importance of diagnosing thyroid cancer early?
Miles:Because many of these patients will be cured with surgery, it’s important that if any new lumps or bumps are found in the neck that patients should have them evaluated as soon as possible. Delaying diagnosis increases the risk of local invasion, most notably to the nerve that supplies the vocal cord on that side of the cancer. If you have surgery and tumor is involving the vocal cords, you may lose some voice function, but you’re probably going to survive the disease, so the earlier you catch it, the less likely you are to have issues such as long-term vocal cord paralysis, swallowing issues, and coughing issues. Thyroid cancers that are left untreated or diagnosed late can often invade other structures in the neck, such as blood vessels, nerves, the trachea, windpipe, or the esophagus. That can affect the ability to swallow and can require extensive surgery when they are found late, so the sooner they are diagnosed and treated the better.
The primary method of diagnosing those patients is with either ultrasound of the neck when there is a suspicious lump that is not going away or in some cases other types of scans, such as an MRI or CT. Generally, an ultrasound is the best way to detect early thyroid cancers. To determine the diagnosis we often use ultrasound guided needle biopsy which is a relatively straightforward office procedure.
TARGETED ONCOLOGY: What individuals are at a higher risk of developing thyroid cancer?
Miles:For thyroid cancers, there are certainly some patients who have a family history of thyroid cancer, and anyone who has thyroid cancer in their family may have some type of genetic abnormality which predisposes them. The inherited types are actually quite rare, but there are several thyroid cancers associated with genetic abnormalities that we can detect with genetic testing of the nodules and the thyroid, so we would perform a biopsy of the thyroid nodules and look specifically at genetic profiles that we can test, which would help us determine the patient’s risk for cancer.
Anyone who has been exposed to radiation in the past, and I’m talking about significant exposures to radiation, is at risk for thyroid cancers. Certainly, the risk in women is slightly higher than the risk in men, especially in younger women, so those are the populations where we tend to see thyroid cancers.
TARGETED ONCOLOGY: What is important for community oncologists to know now about treating patients with thyroid cancer?
Miles:Essentially, when community oncologists are diagnosing and treating patients with thyroid cancer, there are a couple of issues that they need to be aware of. The first is that the underlying primary modality for treatment of these cancers would be high-quality surgery. They need to see a surgeon for evaluation to see if the cancer can be removed safely. If that’s the case, that should always be done. The second thing is to be aware of the molecular testing technology in order to test the cancer for genetic abnormalities. There are two reasons for this: One, it can help us determine the risk factors for recurrence and the risk for the patient, but it also may provide information later if the patient were to have a recurrence, then we would know the original molecular status of the tumor if they became candidates for targeted therapies. We now have new molecular testing and there are several platforms for this that can be used, but that should be performed routinely on the majority of these thyroid cancers in order to determine what the underlying genetic mutation or fusion is that is causing the cancer, when possible.
Anyone that is higher risk, such as females, Asians, those with a history of thyroid cancer in their family, family history of thyroid disease, or exposure to significant radiation, would be somebody that they would need to have a heightened awareness for any thyroid masses or lumps in the neck that are persistent, and should have their physician evaluate them if they notice something abnormal.
TARGETED ONCOLOGY: What genetic abnormalities are tested for in thyroid cancer?
Miles:There are several platforms that have been used to test thyroids. Essentially, these are looking for a variety of genetic patterns, including the most common genetic abnormality which would be important to document, namely theBRAFV600E mutation which portends a higher risk for a thyroid nodule being malignant. We will frequently see a patient with a thyroid nodule and a needle biopsy will be performed, where that needle biopsy will show some atypical cells. The question is, however, what does that atypical cell mean?
The ability to test for those genetic abnormalities such as theBRAFV600E gene, theRASgene, or thePTENmutations as well as others allows us to really counsel the patient on what their risk is that this may be a malignant nodule and may require removal versus observation with ultrasound in order to just follow them along. That’s the most recent development compared to the way we have historically managed these patients. As I stated, theBRAFV600E,RAS,PTEN, and also theTERTmutations, are the most common. There are several others, but those are the most common.
There is another side issue for medical oncologists in that there is a very specific subtype of very aggressive thyroid cancer called ATC. These are very rare cancers, and historically, the prognosis has been so poor that the patients were treated with palliative therapy and often were not treated with curative intent. In many cases, they present with rapid growth and invasion. They are quite a challenge to treat, and we have not had a lot of excellent options for those patients in the past. Recently, there has been some data using MEK inhibitors, which have shown a lot of promise in ATC. For any new patient that presents with a rapidly growing thyroid mass and the biopsy is consistent with ATC, they should have a MEK mutational analysis to see if they are a candidate for a MEK inhibitor as part of their treatment. That is a relatively recent development that community oncologists should be aware of and refer for the appropriate molecular testing in these situations.