Thyroid cancer

Source: Wikipedia, the free encyclopedia.

Thyroid cancer
Five year survival rates 98% (US)[5]
Frequency3.2 million (2015)[6]
Deaths31,900 (2015)[7]

Thyroid cancer is

spread to other parts of the body.[8][9] Symptoms can include swelling or a lump in the neck.[1] Cancer can also occur in the thyroid after spread from other locations, in which case it is not classified as thyroid cancer.[4]

Risk factors include

fine needle aspiration.[1] Screening people without symptoms and at normal risk for the disease is not recommended as of 2017.[10]

Treatment options may include

Five-year survival rates are 98% in the United States.[5]

Globally as of 2015, 3.2 million people have thyroid cancer.

Filipino females.[12] Rates have increased in the last few decades, which is believed to be due to better detection.[11] In 2015, it resulted in 31,900 deaths.[7]

Signs and symptoms

Most often, the first symptom of thyroid cancer is a nodule in the thyroid region of the neck.[13] However, up to 65% of adults have small nodules in their thyroids, but typically under 10% of these nodules are found to be cancerous.[14] Sometimes, the first sign is an enlarged lymph node. Later symptoms that can be present are pain in the anterior region of the neck and changes in voice due to an involvement of the recurrent laryngeal nerve.[15]

Thyroid cancer is usually found in a

Thyroid nodules are of particular concern when they are found in those under the age of 20. The presentation of benign nodules at this age is less likely, thus the potential for malignancy is far greater.[citation needed
]

Causes

Thyroid cancers are thought to be related to a number of environmental and genetic predisposing factors, but significant uncertainty remains regarding their causes.[16]

Environmental exposure to

Fukushima, Kyshtym, and Windscale[18] nuclear disasters.[19] Thyroiditis and other thyroid diseases also predispose to thyroid cancer.[18][20]

Genetic causes include multiple endocrine neoplasia type 2, which markedly increases rates, particularly of the rarer medullary form of the disease.[21]

Diagnosis

papillary thyroid carcinoma

After a

Bethesda system.[26]

After diagnosis, to understand potential for spread of disease, or for follow up monitoring after surgery, a whole body I-131 or I-123 radioactive iodine scan may be performed.[27]

In adults without symptoms, screening for thyroid cancer is not recommended.[28]

Classification

Pie chart of thyroid cancer types by incidence.[29]

Thyroid cancers can be classified according to their

histopathological characteristics.[30][31]
These variants can be distinguished (distribution over various subtypes may show regional variation):

The follicular and papillary types together can be classified as "differentiated thyroid cancer".[37] These types have a more favorable prognosis than the medullary and undifferentiated types.[38]

  • Papillary microcarcinoma is a subset of papillary thyroid cancer defined as a nodule measuring less than or equal to 1 cm.[39] 43% of all thyroid cancers and 50% of new cases of papillary thyroid carcinoma are papillary microcarcinoma.[40][41] Management strategies for incidental papillary microcarcinoma on ultrasound (and confirmed on FNAB) range from total thyroidectomy with radioactive iodine ablation to lobectomy or observation alone. Harach et al. suggest using the term "occult papillary tumor" to avoid giving patients distress over having cancer. Woolner et al. first arbitrarily coined the term "occult papillary carcinoma", in 1960, to describe papillary carcinomas ≤ 1.5 cm in diameter.[42]

Staging

Cancer staging is the process of determining the extent of the development of a cancer. The TNM staging system is usually used to classify stages of cancers, but not of the brain.[43]

  • Stage M1 thyroid cancer
    Stage M1 thyroid cancer
  • Stage N1a thyroid cancer
    Stage N1a thyroid cancer
  • Stage N1b thyroid cancer
    Stage N1b thyroid cancer
  • Stage T1a thyroid cancer
    Stage T1a thyroid cancer
  • Stage T1b thyroid cancer
    Stage T1b thyroid cancer
  • Stage T2 thyroid cancer
    Stage T2 thyroid cancer
  • Stage T3 thyroid cancer
    Stage T3 thyroid cancer
  • Stage T4a thyroid cancer
    Stage T4a thyroid cancer
  • Stage T4b thyroid cancer
    Stage T4b thyroid cancer

Metastases

Detection of differentiated thyroid cancer metastases may be detected by performing a full-body scintigraphy using iodine-131.[44][45]

Spread

Thyroid cancer can spread directly, via lymphatics or blood. Direct spread occurs through infiltration of the surrounding tissues. The tumor infiltrates into

Cervical lymph nodes become palpable in papillary carcinoma even when the primary tumor is unpalpable. Deep cervical nodes, pretracheal, prelaryngeal, and paratracheal groups of lymph nodes are often affected. The lymph node affected is usually the same side as that of the location of the tumor. Blood spread is also possible in thyroid cancers, especially in follicular and anaplastic carcinoma. The tumor emboli do angioinvasion of lungs; end of long bones, skull, and vertebrae are affected. Pulsating metastases occur because of their increased vascularity.[46]

Treatment

Thyroidectomy and dissection of central neck compartment is the initial step in treatment of thyroid cancer in the majority of cases.[13] Thyroid-preserving operations may be applied in cases, when thyroid cancer exhibits low biological aggressiveness (e.g. well-differentiated cancer, no evidence of lymph-node metastases, low MIB-1 index, no major genetic alterations like BRAF mutations, RET/PTC rearrangements, p53 mutations etc.) in patients younger than 45 years.[47] If the diagnosis of well-differentiated thyroid cancer (e.g. papillary thyroid cancer) is established or suspected by

overtreatment of thyroid cancer among old patients.[49]

Radioactive iodine-131 is used in people with papillary or follicular thyroid cancer for ablation of residual thyroid tissue after surgery and for the treatment of thyroid cancer.[50] Patients with medullary, anaplastic, and most Hurthle-cell cancers do not benefit from this therapy.[13]

External irradiation may be used when the cancer is unresectable, when it recurs after resection, or to relieve pain from bone metastasis.[13]

Sorafenib and lenvatinib are approved for advanced metastatic thyroid cancer.[51] Numerous agents are in phase II and III clinical trials.[51]

Post surgical monitoring for recurrence or metastasis may include routine ultrasound, CT scans, FDG-PET/CT, radioactive iodine whole body scans, and routine laboratory blood tests for changes in thyrogolubin, thyroglobuilin antibodies, or calcitonin, depending on the variant of thyroid cancer.[52][53][54]

Prognosis

The prognosis of thyroid cancer is related to the type of cancer and the stage at the time of diagnosis. For the most common form of thyroid cancer, 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 thyroid cancers (mostly papillary) will not grow or metastasize. This view holds the overwhelming majority of thyroid cancers 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.[55] Thyroid cancer is incredibly common, with autopsy studies of people dying from other causes showing that more than one-third of older adults technically have thyroid cancer, which is causing them no harm.[55] 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 thyroid cancer; sometimes, a benign nodule is discovered, but surgery uncovers an incidental small thyroid cancer. 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 thyroid cancers will ever have any symptoms, and treatment in such patients has the potential to cause harm to them, not to help them.[55][56]

Thyroid cancer is three times more common in women than in men, but according to European statistics,

5-year survival rate for thyroid cancer is 85% for females and 74% for males.[58]

The table below highlights some of the challenges with decision making and prognostication in thyroid cancer. While general agreement exists that stage I or II papillary, follicular, or medullary cancer have good prognoses, when evaluating a small thyroid cancer to determine which ones will grow and metastasize and which will not is not possible. As a result, once a diagnosis of thyroid cancer 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 thyroid cancer. While many present with widely metastatic disease, an equal number evolve over years and decades from stage I or II disease. Physicians who manage thyroid cancer of any stage recognize that a small percentage of patients with low-risk thyroid cancer will progress to metastatic disease.

Improvements have been made in thyroid cancer 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

vascular endothelial growth factor receptor, and the epidermal growth factor receptor.[59]
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" thyroid cancers. Other targeted therapies are being evaluated, making life extension possible over the next 5–10 years for those with stage III and IV thyroid cancer.

Prognosis is better in younger people than older ones.[58]

Prognosis depends mainly on the type of cancer and

cancer stage
.

 
Thyroid cancer type
5-year survival 10-year survival
Stage I Stage II Stage III Stage IV Overall Overall
Papillary 100%[60] 100%[60] 93%[60] 51%51%[60] 96%[61] or 97%[62] 93%[61]
Follicular 100%[60] 100%[60] 71%[60] 50%[60] 91%[61] 85%[61]
Medullary 100%[60] 98%[60] 81%[60] 28%[60] 80%,[61] 83%[63] or 86%[64] 75%[61]
Anaplastic (always stage IV)[60] 7%[60] 7%[60] or 14%[61] (no data)

Epidemiology

Thyroid cancer, in 2010, resulted in 36,000 deaths globally up from 24,000 in 1990.[65] Obesity may be associated with a higher incidence of thyroid cancer, but this relationship remains the subject of much debate.[66]

Thyroid cancer accounts for less than 1% of cancer cases and deaths in the UK. Around 2,700 people were diagnosed with thyroid cancer in the UK in 2011, and around 370 people died from the disease in 2012.[67]

However, in South Korea, thyroid cancer was the 5th most prevalent cancer, which accounted for 7.7% of new cancer cases in 2020.[68]

Notable cases

References

  1. ^ a b c d e f g h i j "Thyroid Cancer Treatment". National Cancer Institute. 27 April 2017. Archived from the original on 15 July 2017. Retrieved 18 July 2017.
  2. ^
    PMID 24274180
    .
  3. ^ .
  4. ^ a b c d e f "Thyroid Cancer Treatment". National Cancer Institute. 12 May 2017. Archived from the original on 16 July 2017. Retrieved 18 July 2017.
  5. ^ a b c d "Cancer of the Thyroid - Cancer Stat Facts". seer.cancer.gov. Archived from the original on 15 July 2017. Retrieved 18 July 2017.
  6. ^
    PMID 27733282
    .
  7. ^ .
  8. ^ "Cancer Fact sheet N°297". World Health Organization. February 2014. Archived from the original on 29 December 2010. Retrieved 10 June 2014.
  9. ^ "Defining Cancer". National Cancer Institute. 17 September 2007. Archived from the original on 25 June 2014. Retrieved 10 June 2014.
  10. S2CID 205091526
    .
  11. ^ .
  12. .
  13. ^ on 28 February 2010.
  14. .
  15. ^ "Thyroid Cancer". Herbert Irving Comprehensive Cancer Center (HICCC) - New York. 1 February 2021. Archived from the original on 5 February 2023. Retrieved 5 February 2023.
  16. ^ "Thyroid Cancer Overview - Signaling Pathway. Diagnosis. Targeted Therapy - Creative Biolabs". www.creativebiolabs.net. Archived from the original on 5 February 2023. Retrieved 5 February 2023.
  17. ^ "Radioactive I-131 from Fallout". National Cancer Institute. Archived from the original on 19 May 2014. Retrieved 9 June 2014.
  18. ^
    PMID 8431362
    .
  19. ^ "Experts link higher incidence of children's cancer to Fukushima radiation". ScienceAlert. 12 October 2015. Archived from the original on 19 January 2016. Retrieved 15 January 2016.
  20. PMID 20555084
    .
  21. ^ "Genetics of Endocrine and Neuroendocrine Neoplasias". National Cancer Institute. 1 January 1980. Archived from the original on 4 July 2014. Retrieved 9 June 2014.
  22. PMID 31559190
    .
  23. .
  24. ^ "Thyroid scan: MedlinePlus Medical Encyclopedia". medlineplus.gov. Archived from the original on 27 January 2021. Retrieved 5 February 2021.
  25. ^ "Vol 7 Issue 6 p.3-4". American Thyroid Association. Archived from the original on 4 December 2020. Retrieved 5 February 2021.
  26. PMID 24294568
    .
  27. .
  28. .
  29. .
  30. ^ "Thyroid Cancer Treatment". National Cancer Institute. 1 January 1980. Archived from the original on 21 April 2008. Retrieved 22 December 2007.
  31. ^ "Thyroid cancer". National Cancer Institute. Archived from the original on 20 December 2007. Retrieved 22 December 2007.
  32. ^ . 8th edition.
  33. .
  34. .
  35. .
  36. ^ "Anaplastic Thyroid Cancer". Columbia Thyroid Center. Archived from the original on 23 December 2019. Retrieved 30 March 2020.
  37. from the original on 20 May 2013.
  38. .
  39. .
  40. .
  41. .
  42. .
  43. ^ "Cancer Staging - NCI". www.cancer.gov. 9 March 2015. Archived from the original on 19 March 2015. Retrieved 5 February 2023.
  44. PMID 17914109
    .
  45. .
  46. .
  47. ^ .
  48. (PDF) on 26 December 2011. Retrieved 12 July 2013.
  49. . Retrieved 7 October 2012.
  50. .
  51. ^ .
  52. .
  53. .
  54. .
  55. ^ .
  56. .
  57. ^ "Thyroid Cancer". MedicineNet.com. Archived from the original on 20 October 2011. Retrieved 26 October 2011.
  58. ^ .
  59. ^ "FDA approves new treatment for rare form of thyroid cancer" (Press release). U.S. Food and Drug Administration. 6 April 2011. Archived from the original on 10 April 2011. Retrieved 7 April 2011.
  60. ^ a b c d e f g h i j k l m n o cancer.org Thyroid Cancer Archived 18 October 2013 at the Wayback Machine By the American Cancer Society. In turn citing: AJCC Cancer Staging Manual (7th ed).
  61. ^ . (Note:Book also states that the 14% 10-year survival for anaplastic thyroid cancer was overestimated)
  62. ^ Rounded up to nearest natural number from 96.7% as given by Santacroce L, Gagliardi S, Kennedy AS (28 September 2010). "Thyroid, Papillary Carcinoma". eMedicine. Archived from the original on 28 July 2010.
  63. PMID 16091497
    .
  64. ^ "Medullary Thyroid Cancer". National Cancer Institute. 4 February 2016. Archived from the original on 30 May 2016. Retrieved 11 May 2016.
  65. S2CID 1541253
    .
  66. from the original on 11 November 2014.
  67. ^ "Thyroid cancer statistics". Cancer Research UK. Archived from the original on 17 October 2014. Retrieved 28 October 2014.
  68. ^ "Republic of Korea Cancer Rates" (PDF). Global Cancer Observatory (GCO). World Health Organization. 2020. Archived (PDF) from the original on 11 November 2022. Retrieved 5 February 2022.
  69. ^ "Callum Ainley: Grimsby Town midfielder diagnosed with thyroid cancer". BBC Sport. 16 January 2024. Retrieved 17 January 2024.
  70. ^ Hunsley, James (27 January 2023). "'I am so grateful' - ex-Liverpool midfielder Emre Can opens up on battle with cancer". Goal.com. Archived from the original on 28 January 2023. Retrieved 29 January 2023.
  71. ^ Bamberger, Michael (27 May 2002). "Survivors". Sports Illustrated. Archived from the original on 1 March 2014. Retrieved 11 August 2013.
  72. ^ "Uhm Jung-hwa had Thyroid cancer op". The Korean Herald. 20 October 2010. Archived from the original on 5 February 2022. Retrieved 5 February 2022.
  73. ^ "Lee Moon-se risks cancer relapse to keep singing". The Korean Herald. 31 March 2015.
  74. ^ "Thyroid surgeon Dr. Gary Clayman teaches Danny about his cancer diagnosis". WFLA. 25 January 2021. Archived from the original on 20 February 2021. Retrieved 6 February 2021.
  75. ^ "Danny shares he has thyroid cancer, advocates for awareness". WFLA. 25 January 2021. Archived from the original on 1 February 2021. Retrieved 6 February 2021.
  76. ^ "Danny New is heading back to the Sunshine State". WWLP. 3 December 2019. Archived from the original on 8 August 2020. Retrieved 6 February 2021.
  77. ^ Jacobs E (3 April 2022). "Putin under care of cancer doctor, bathing in deer antler blood: Report". Washington Examiner. Archived from the original on 3 April 2022. Retrieved 3 April 2022.
  78. ^ Lane C (8 September 2005). "Rehnquist Eulogies Look Beyond Bench". The Washington Post. Archived from the original on 4 March 2016. Retrieved 11 May 2016.
  79. ^ "Celebrities with Thyroid problems". Alexander Shifrin. Archived from the original on 26 August 2013. Retrieved 11 August 2013.

External links