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Follicular Thyroid Carcinoma Clinical Presentation

  • Author: Luigi Santacroce, MD; Chief Editor: Jules E Harris, MD, FACP, FRCPC  more...
 
Updated: Jul 15, 2016
 

History

Many cases of follicular thyroid cancer (FTC) are subclinical. The most common presentation of thyroid cancer is an asymptomatic thyroid mass or nodule that can be felt in the neck. Pain seldom is an early warning sign of thyroid cancer.

Record a thorough medical history to identify any risk factors or symptoms. For any patient with a lump in the thyroid that has appeared recently, focus on obtaining history regarding every prior exposure to ionizing radiation, as well as the cumulative lifetime exposure. Consider family history of thyroid cancer.[11]

Some patients have persistent cough, difficulty breathing, or difficulty swallowing. Other symptoms (eg, pain, stridor, vocal cord paralysis, hemoptysis, rapid enlargement) are rare. These symptoms can be caused by less serious problems.

At diagnosis, 10-15% of patients have distant metastases to bone and lung and initially are evaluated for pulmonary or osteoarticular symptoms (eg, pathologic fracture, spontaneous fracture).

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Physical

Palpate the patient's neck to evaluate the size and firmness of the thyroid and to check for any thyroid nodules. The principal sign of thyroid carcinoma is a firm and nontender nodule in the thyroid area. This mass is painless.

Some patients have a tight or full feeling in the neck, hoarseness, or signs of tracheal or esophageal compression.

Palpable thyroid nodules are usually solitary, with a hard consistency, an average size of less than 5 cm, and ill-defined borders. This nodule is fixed in respect to surrounding tissues and moves with the trachea at swallowing.

Usually, signs of hyperthyroidism or hypothyroidism are not observed.

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Causes

The thyroid is particularly sensitive to the effects of ionizing radiation. Exposure to ionizing radiation results in a 30% risk for thyroid cancer.

A history of exposure of the head and neck to x-ray beams, especially during childhood, has been recognized as an important contributing factor to the development of thyroid cancer.

Seven percent of the individuals exposed to the atomic bomb blasts in Japan developed thyroid cancers. However, exposure to fallout from the Chernobyl nuclear accident was asssociated with increases in papillary rather than follicular thyroid carcinoma.[12, 13]

Therapeutic irradiation of body areas was used to treat tumors and benign conditions, such as acne, excessive facial hair, tuberculosis in the neck, fungal diseases of the scalp, sore throats, chronic coughs, and enlargement of the thymus, tonsils, and adenoids, from the 1920s to the 1960s. About 10% of these individuals who were treated with irradiation developed thyroid cancer after a latency period of 30 years.

Patients who need radiotherapy for certain types of cancer of the head and neck area also may have an increased risk of developing thyroid cancer.

Exposure to diagnostic x-rays does not increase the risk of developing thyroid cancer.

Although follicular cancer is frequently present in goitrous thyroids, the relationship between prolonged elevation of thyroid-stimulating hormone (TSH) and follicular carcinoma is not known.

Several reports have shown a relationship between iodine deficiency and the incidence of thyroid carcinoma.

Incidence of FTC has decreased in geographic areas of endemic goiter after iodized salt was introduced.

Some studies demonstrate that mutations of the ras oncogene could be implicated in the neoplastic transformation of thyrocytes in FTC. n-ras and h-ras mutations (in codon 61) should be the first events in the pathogenesis of FTC, followed by several further mutations (ie, deletions on chromosomes 3q, 11, and 13q).

Some molecules that physiologically regulate the growth of the thyrocytes, as interleukins (IL-1 and IL-8) or other cytokines (IGF1, TGF-beta, EGF) could play a role in the pathogenesis of FTC.

More recently, a histochemical study has shown that delta Np73 plays a role predominantly in the early phase of thyroid carcinoma progression.[14] As a consequence, this seems to be a new effective marker to differentiate follicular adenomas and carcinomas of the thyroid.

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Contributor Information and Disclosures
Author

Luigi Santacroce, MD Assistant Professor, Medical School, State University at Bari, Italy

Disclosure: Nothing to disclose.

Coauthor(s)

Lodovico Balducci, MD Professor, Oncology Fellowship Director, Department of Internal Medicine, Division of Adult Oncology, H Lee Moffitt Cancer Center and Research Institute, University of South Florida Morsani College of Medicine

Lodovico Balducci, MD is a member of the following medical societies: American Association for the Advancement of Science, American Association for Cancer Research, American College of Physicians, American Geriatrics Society, American Society of Hematology, New York Academy of Sciences, American Society of Clinical Oncology, Southern Society for Clinical Investigation, International Society for Experimental Hematology, American Federation for Clinical Research, American Society of Breast Disease

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Benjamin Movsas, MD 

Benjamin Movsas, MD is a member of the following medical societies: American College of Radiology, American Radium Society, American Society for Radiation Oncology

Disclosure: Nothing to disclose.

Chief Editor

Jules E Harris, MD, FACP, FRCPC Clinical Professor of Medicine, Section of Hematology/Oncology, University of Arizona College of Medicine, Arizona Cancer Center

Jules E Harris, MD, FACP, FRCPC is a member of the following medical societies: American Association for the Advancement of Science, American Society of Hematology, Central Society for Clinical and Translational Research, American Society of Clinical Oncology

Disclosure: Nothing to disclose.

Additional Contributors

Philip Schulman, MD Chief, Medical Oncology, Department of Medicine, Memorial Sloan-Kettering Cancer Center

Philip Schulman, MD is a member of the following medical societies: American Association for Cancer Research, American College of Physicians, American Society of Hematology, Medical Society of the State of New York

Disclosure: Nothing to disclose.

Acknowledgements

Silvia Gagliardi, MD Consulting Staff, Department of Surgery, Medical Center Vita, Italy

Disclosure: Nothing to disclose.

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Surgical specimen of a large goiter. Total thyroidectomy was performed because of the presence of a solid nodule in the right lobe (note the size of the thyroid lobe at left of the screen).
The right lobe of the thyroid was sectioned and reveals a large solid nodule with necrotic and hemorrhagic areas. Histologic diagnosis is follicular thyroid carcinoma.
Histologic pattern of a mildly differentiated follicular thyroid carcinoma (250 X). Image courtesy of Professor Pantaleo Bufo at University of Foggia, Italy.
Histologic pattern of a rare lymph node metastasis of follicular thyroid carcinoma (140 X). Image courtesy of Professor Pantaleo Bufo at University of Foggia, Italy.
Histologic pattern of a rare lymph node metastasis of follicular thyroid carcinoma (250 X). Image courtesy of Professor Pantaleo Bufo at University of Foggia, Italy.
 
 
 
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