Papillary Thyroid Cancer: Genetic Alterations and Molecular Biomarker Investigations

Abstract

Papillary thyroid cancer (PTC) is the most prevalent form of malignancy among all cancers of the thyroid. It is also one of the few cancers with a rapidly increasing incidence. PTC is usually contained within the thyroid gland and generally biologically indolent. Prognosis of the cancer is excellent, with less than 2% mortality at 5 years. However, more than 25% of patients with PTC developed a recurrence during a long term follow-up. The present article provides an updated condensed overview of PTC, which focuses mainly on the molecular alterations involved and recent biomarker investigations.

Keywords: biomarker; diagnostics; genetic signature; molecular alteration; papillary thyroid cancer.

Figure 1

Classification of thyroid tumours. *There are 15 variants of papillary thyroid carcinoma but only the top 6 listed variants are included in this illustration ; FT-UMP, Follicular tumour of uncertain malignant potential; WDT-UMP, Well-differentiated tumour of uncertain malignant potential; NIFTP, Non-invasive follicular thyroid neoplasm with papillary nuclear features; CASTLE, Carcinoma showing thymus-like differentiation/intrathyroid epithelial thymoma; PNSTs, Peripheral nerve sheath tumour.

Figure 2

Oncogenic activation of MAPK pathway. The pathway is triggered by binding of growth factor (GF) to a receptor tyrosine kinase (RTK), which activates the RAS, BRAF, MEK and ERK phosphorylation cascade. MEK: MAPK kinase; ERK: extracellular-signal-regulated kinase.