Thyroid Cancer - Research Paper Example

Overall prevalence of cancer in nodule is 5-15% with reportedly higher occurrence rates in female (representing ratio of 3:1) and older patients. National Cancer Institute reports about 56,000 cases of thyroid cancer in U.S each year (Norman, 2009). Thyroid carcinomas represent less than 1% of all human cancers with global incidence rates from 0.5-10% per 100,000 populations (IAEA, 2009) Risk Factors: Studies indicate that exposure to radiation, iodine intake, family history of thyroid cancer, chronic goiter etc are suspected a risk factors for thyroid cancer (IAEA, 2009).

Clinical Presentation: Thyroid gland is actively involved in metabolic functions of the body and therefore, patients with thyroid malfunction present with wide range of symptoms. Generally the enlargements of gland either diffuse or asymptomatic hard rapidly growing nodule is major sign of thyroid cancer. However, the evaluation of these nodules as malignant or benign is major concern (IAEA, 2009). Other symptoms may include cough, difficulty in swallowing, swelling in neck region, hoarsened voice, thyroid gland enlargement, morphological abnormality or calcification of thyroid etc.

History and physical examination: On physical examination, a hard rapidly growing nodule with swollen lymph nodes is observed. . Radiological imaging of thyroid can be done through high resolution ultrasound, thin section CT scan or MRI. Yet, the initial evaluation should be focused on clinical history, physical examination, serum hormone levels further supported by FNA (IAEA, 2009). Thyroid ultrasound is widely used technique in diagnostics and reveals characteristics such as micro-calcifications, hypoechogenicity, irregular borders and intranodal blood flow etc.

These patterns increase the suspicion of malignancy; however, fine needle aspiration cytology (FNAC) should be utilized to confirm diagnosis. FNAC is suggestively performed on thyroid nodule of 1 cm on clinical presentation and family history (Pacini et al., 2010). Other tests to evaluate and classify thyroid cancer include thyroid biopsy and laryngoscopy. Types of Thyroid cancer: Thyroid cancers can be classified into epithelial or non-epithelial. Epithelial malignant neoplasms originate from follicular or parafollicular C-cells, whereas, sarcomas and malignant lymphomas constitute non-epithelial tumors. 1. Follicular carcinoma is malignant tumors of epithelial cells that exhibit follicular cell differentiation.

These represent about 25-40% of thyroid cancers. Follicular carcinomas can be classified into a. minimally invasive carcinomas: excellent prognosis with 95% recovery rate. b. Widely invasive carcinomas present excessive invasion of neoplasm of surrounding tissue. Prognosis is good with 20% reported mortality rate (IAEA, 2009). 2. Insular or poorly differentiated carcinomas arise from follicular cells rapidly converting into aggressive neoplasm which later metastasizes to local and distant lymph nodes.

Poor prognosis and higher mortality