Hashimotos Thyroiditis and Thyroid Cancer
Condition: Thyroid Cancer; Hashimotos Thyroiditis
MeSH terms: Thyroid Neoplasms; Thyroid Diseases; Thyroiditis; Hashimoto Disease
Study type: Observational

Summary: 
      Thyroid cancer (TC) is the most common endocrine malignancy. The association between
      inflammation and cancer is well established but the association between thyroiditis
      (inflammation of thyroid gland) especially Hashimoto's thyroiditis (HT) and thyroid cancer
      remains controversial. Chronic inflammation leads to a repeated cycle of cellular damage and
      subsequent healing which contributes to inappropriate cell proliferation and subsequent
      neoplastic transformation. One of the most common forms of Thyroiditis is Hashimoto's
      thyroiditis which is a chronic autoimmune inflammatory disease affects almost 5% of the
      population and is more common in women. For the first time, Dailey and Lindsay reported in
      1955 an increased association between Hashimoto's Thyroiditis (HT) and thyroid cancer. They
      reported 35 thyroid cancers in 278 patients with Hashimoto's Thyroiditis, a prevalence of
      17.7% which they considered higher than the general population . Since then, various studies
      have been done, some studies have reported an increased risk of malignancy in Hashimoto's
      thyroiditis; others have failed to find an association. Most of the studies that have been
      done to identify the association between Hashimoto's thyroiditis and thyroid cancer are
      retrospective. The purpose of this pilot case-control study is to identify the association of
      Hashimoto's thyroiditis and thyroid cancer, to determine if the presence of Hashimoto's
      thyroiditis has any affect on the complication of thyroidectomy and prognostic factors of
      thyroid cancer.
    

Detailed description: 
      AIM1: To identify the association between Hashimoto's Thyroiditis and thyroid cancer by
      comparing the prevalence of thyroid cancer in patients with Hashimoto's Thyroiditis and
      patients without Hashimoto's Thyroiditis who undergoing Thyroidectomy for a variety of
      indications in UTMB in 12 months period of the study.

      AIM2: Compare Ultrasound (US) characteristics preoperatively in two groups of patients with
      thyroid cancer and Hashimoto's thyroiditis and patients with thyroid cancer but without
      Hashimoto's thyroiditis.

      AIM3: compare prognostic factors including tumor diameter, vascular and capsular invasion,
      extra thyroid invasion, lymph node metastasis, distant metastasis in two groups of patients
      including patients with thyroid cancer and Hashimoto's thyroiditis and patients with thyroid
      cancer but without Hashimoto's thyroiditis.

      AIM4: Compare the complication of surgery in patients with thyroid cancer and Hashimoto's
      Thyroiditis and patients with thyroid cancer but without Hashimoto's thyroiditis.

      AIM5: Compare inflammatory factors in two group of patient with thyroid cancer and
      Hashimoto's Thyroiditis and patients with thyroid cancer but without Hashimoto's thyroiditis.

      Coordinator in the ear, nose and throat (ENT) clinic will notify the assigned investigator
      about any patient admitted to UTMB for thyroidectomy. The investigator will meet and
      interview the patient to obtain the consent and fill out a data collection sheet which will
      include demographic data, history of thyroid disease, history of thyroid medications, history
      of radiotherapy of head and neck or radioactive iodine therapy, family history of thyroid
      disease or thyroid cancer. Patients meeting the inclusion criteria will be given the
      opportunity to participate in the study. All patients will have blood drawn. Blood samples
      will be stored in Endocrinology lab to measure Anti-TPO, Ca, PTH and inflammatory factors at
      the end of study. A chart review of all enrolled patients will be performed to obtain details
      of the preoperative thyroid U/S characteristics including echogenicity, texture,
      calcification, vascularity and TSH and Free T4 level. Postoperative histopathology evaluation
      will be done by a pathologist experienced in thyroid pathology. The diagnosis of Hashimoto's
      thyroiditis (HT ) will be made based on histopathology finding and AntiTPO level. The
      histopathology criteria for Hashimoto's thyroiditis (HT) must be seen in a normal region of
      the thyroid gland, distinct from the site of thyroid cancer. UTMB Subjects will be divided to
      two groups, subjects with Hashimoto's Thyroiditis and subjects without Hashimoto's
      Thyroiditis (control group).The prevalence of thyroid cancer will be compared in these two
      groups.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All patients undergoing thyroidectomy for a variety of indications at University of Texas
        Medical Branch in Galveston between June 2011-May 2012
      
Biospecimen description: 
      Plasma samples with be stored to measure anti inflammatory factors.
    
Keywords: Thyroid cancer; Hashimotos thyroiditis; Thyroidectomy; Anti-inflammatory factors