Thyroid Cancer

Abstract

Thyroid tumors include those that originate from follicular cells and those that arise from parafollicular cells (C cells). Differentiated thyroid cancer, which originates from follicular cells, includes papillary carcinoma, follicular carcinoma, oncocytic cell carcinoma (Hürthle), poorly differentiated carcinoma, and anaplastic carcinoma. The incidence of thyroid cancer has been increasing significantly, with an estimated incidence in the United States of America of 53,990 cases by the year 2018. This neoplasm is listed as the most common endocrine tumor and represents approximately 3% of all malignant tumors in humans, with 75% of cases occurring in women, and two-thirds of cases occurring in people under 55 years. The increase in the prevalence/incidence of low-risk thyroid cancer over the last 10 to 20 years has required a re-appraisal of the standard one-size-fits-all approach to differentiated thyroid cancer. This adaptation to a more individualized management of the patient with thyroid cancer has led to a much more risk-adapted approach to the diagnosis, initial therapy, adjuvant therapy, and follow-up of patients with differentiated thyroid cancer. This paper with review the current understanding of the clinical presentation, diagnostic workup, and management of thyroid cancer centered on evidence-based and personalized medicine.

Current Understanding of Papillary Thyroid Carcinoma

“…In PTC its nuclear characteristics differentiate it from other thyroid neoplasms, permitting it to be diagnosed on fine-needle aspiration (FNA) [56]. Furthermore, PTC is depicted by having branching papillae with a central fibrovascular stalk (Figure 1) [5] [57]. The branching papillae are covered by cells with eosinophilic cytoplasm [57] [58].…”

“…The Psammoma bodies are concentric, lamellated, calcified spheres composed in part of thyroglobulin are seen in roughly 50% of the cases [8] [57] [59] [60]. Some tumors may also contain multinucleated giant cells [5] [57]. Classical PTC, is typically unencapsulated with invasive and ill-defined margins [5] [61].…”

“…Some tumors may also contain multinucleated giant cells [5] [57]. Classical PTC, is typically unencapsulated with invasive and ill-defined margins [5] [61]. All the same, this common pathologic variant generally has an excellent prognosis [1] [5].…”

“…The macroscopic appearance of PTC can be very variable. Most PTC tend to be distinctly well circumscribed, solid, firm, and white in color, but a significant percentage of tumors can be cystic [5] [57]. A relatively common presentation of PTC is cystic metastases to region lymph nodes and the presence of a solid primary tumor [62].…”

“…Nevertheless, this entity has a broad range of biological and clinical behavior that can result in disease recurrence and death, depending on patient and tumor characteristics and the initial management approach. PTC is the most common form of well-differentiated thyroid cancer (WDTC) and based on the most recent statistics, accounts for approximately 89.4% of all thyroid malignancies, and is the predominant histology observed in patients exposed to radiation [1] [2] [3] [4] [5]. The average age of diagnosis of PTC is between 30 and 40 years, women are affected more frequently than men at a 2:1 ratio [6] [7] [8].…”