The prognosis of<unk>  is related to the type of cancer and the stage at the time of diagnosis. For the most common form of<unk> , papillary, the overall prognosis is excellent. Indeed, the increased incidence of papillary thyroid carcinoma in recent years is likely related to increased and earlier diagnosis. One can look at the trend to earlier diagnosis in two ways. The first is that many of these cancers are small and not likely to develop into aggressive malignancies. A second perspective is that earlier diagnosis removes these cancers at a time when they are not likely to have spread beyond the thyroid gland, thereby improving the long-term outcome for the patient. No consensus exists at present on whether this trend toward earlier diagnosis is beneficial or unnecessary. The argument against early diagnosis and treatment is based on the logic that many small<unk> s (mostly papillary) will not grow or metastasize. This view holds the overwhelming majority of<unk> s are overdiagnosed that is, will never cause any symptoms, illness, or death for the patient, even if nothing is ever done about the cancer. Including these overdiagnosed cases skews the statistics by lumping clinically significant cases in with apparently harmless cancers.<unk>  is incredibly common, with autopsy studies of people dying from other causes showing that more than one-third of older adults technically have<unk> , which is causing them no harm. Detecting nodules that might be cancerous is easy, simply by feeling the throat, which contributes to the level of overdiagnosis. Benign (noncancerous) nodules frequently co-exist with<unk> ; sometimes, a benign nodule is discovered, but surgery uncovers an incidental small<unk> . Increasingly, small thyroid nodules are discovered as incidental findings on imaging (CT scan, MRI, ultrasound) performed for another purpose; very few of these people with accidentally discovered, symptom-free<unk> s will ever have any symptoms, and treatment in such patients has the potential to cause harm to them, not to help them.<unk>  is three times more common in women than in men, but according to European statistics, the overall relative 5-year survival rate for<unk>  is 85% for females and 74% for males. The table below highlights some of the challenges with decision making and prognostication in<unk> . While general agreement exists that stage I or II papillary, follicular, or medullary cancer have good prognoses, when evaluating a small<unk>  to determine which ones will grow and metastasize and which will not is not possible. As a result, once a diagnosis of<unk>  has been established (most commonly by a fine needle aspiration), a total thyroidectomy likely will be performed. This drive to earlier diagnosis has also manifested itself on the European continent by the use of serum calcitonin measurements in patients with goiter to identify patients with early abnormalities of the parafollicular or calcitonin-producing cells within the thyroid gland. As multiple studies have demonstrated, the finding of an elevated serum calcitonin is associated with the finding of a medullary thyroid carcinoma in as high as 20% of cases. In Europe where the threshold for thyroid surgery is lower than in the United States, an elaborate strategy that incorporates serum calcitonin measurements and stimulatory tests for calcitonin has been incorporated into the decision to perform a thyroidectomy; thyroid experts in the United States, looking at the same data, have for the most part not incorporated calcitonin testing as a routine part of their evaluations, thereby eliminating a large number of thyroidectomies and the consequent morbidity. The European thyroid community has focused on prevention of metastasis from small medullary thyroid carcinomas; the North American thyroid community has focused more on prevention of complications associated with thyroidectomy (see American Thyroid Association guidelines below). As demonstrated in the table below, individuals with stage III and IV disease have a significant risk of dying from<unk> . While many present with widely metastatic disease, an equal number evolve over years and decades from stage I or II disease. Physicians who manage<unk>  of any stage recognize that a small percentage of patients with low-risk<unk>  will progress to metastatic disease. Improvements have been made in<unk>  treatment during recent years. The identification of some of the molecular or DNA abnormalities has led to the development of therapies that target these molecular defects. The first of these agents to negotiate the approval process is vandetanib, a tyrosine kinase inhibitor that targets the RET proto-oncogene, two subtypes of the vascular endothelial growth factor receptor, and the epidermal growth factor receptor. More of these compounds are under investigation and are likely to make it through the approval process. For differentiated thyroid carcinoma, strategies are evolving to use selected types of targeted therapy to increase radioactive iodine uptake in papillary thyroid carcinomas that have lost the ability to concentrate iodide. This strategy would make possible the use of radioactive iodine therapy to treat "resistant"<unk> s. Other targeted therapies are being evaluated, making life extension possible over the next 5–10 years for those with stage III and IV<unk> . Prognosis is better in younger people than older ones. Prognosis depends mainly on the type of cancer and cancer stage.<unk>  type 5-year survival 10-year survival Stage I Stage II Stage III Stage IV Overall Overall Papillary 100% 100% 93% 51%51% 96% or 97% 93% Follicular 100% 100% 71% 50% 91% 85% Medullary 100% 98% 81% 28% 80%, 83% or 86% 75% Anaplastic (always stage IV) 7% 7% or 14% (no data)
Thyroid cancer
Metastasis
Papillary thyroid cancer
Thyroid nodule
Thyroid lymphoma
Medullary thyroid cancer
Thyroid neoplasm
Follicular thyroid cancer