Identifying a risk profile for thyroid cancer

Abstract

The large use of simple and effective diagnostic tools has significantly contributed to the increase in diagnosis of thyroid cancer over the past years. However, there is compelling evidence that most micropapillary carcinomas have an indolent behavior and may never evolve into clinical cancers. Therefore, there is an urgent need for new tools able to predict which thyroid cancers will remain silent, and which thyroid cancers will present an aggressive behavior. There are a number of well-established clinical predictors of malignancy and recent studies have suggested that some of the patient's laboratory data and image methods may be useful. Molecular markers have also been increasingly tested and some of them appear to be very promising, such as BRAF, a few GST genes and p53 polymorphisms. In addition, modern tools, such as immunocytochemical markers, and the measure of the fractal nature of chromatin organization may increase the specificity of the pathological diagnosis of malignancy and help ascertain the prognosis. Guidelines designed to select nodules for further evaluation, as well as new methods aimed at distinguishing carcinomas of higher aggressiveness among the usually indolent thyroid tumors are an utmost necessity. O uso cada vez mais freqüente de métodos diagnósticos simples e efetivos tem contribuído significativamente para um aumento no diagnóstico de câncer da tiróide nos últimos anos. Entretanto, existem importantes evidências de que muitos dos microcarcinomas papilíferos têm um comportamento indolente e podem nunca evoluir para cânceres clínicos. Existe, portanto, uma necessidade urgente de desenvolver novas ferramentas capazes de predizer quais os tumores tiroidianos que permanecerão silenciosos e quais desenvolverão comportamento agressivo. Há uma série de marcadores clínicos de evolução bem estabelecidos e alguns estudos recentes sugerem que dados laboratoriais e métodos de imagem podem ser úteis. Marcadores moleculares também vêm sendo ativamente investigados e alguns, como BRAF, os genes GST e polimorfismos de p53, parecem promissores. Além disso, marcadores imunocitoquímicos e a medida da natureza fractal da cromatina podem aumentar a especificidade do diagnóstico anatomopatológico e ajudar a predizer o prognóstico. Existe uma necessidade imperiosa de elaborarmos diretrizes destinadas a selecionar os nódulos que merecem prosseguimento em sua avaliação, assim como novos métodos capazes de identificar lesões mais agressivas entre os geralmente indolentes tumores tiroidianos.

Evolution of thyroid cancer mortality in adults in Brazil

“…Indeed, mortality is higher in the group of women, which corroborates findings reported nationally and internationally (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40). This does not mean that thyroid cancer among men is presented as a problem of lower order.…”

“…In the United States, differentiated thyroid cancer (DTC) is a tumor whose incidence has grown over the years between 1992 and 2002, and it is currently the eighth most common cancer among women. This increase reached levels of 6.3% per year between 1997 and 2003 [Surveillance, Epidemiology, and End Results Program (SEER) -available on the website of the American Cancer Society] (25)(26)(27).…”

Evidence that polymorphisms in detoxification genes modulate the susceptibility for sporadic medullary thyroid carcinoma

“…In addition, polymorphisms of relevant xenobiotic metabolizing enzymes may be used as toxicological susceptibility markers, as our group and others have demonstrated in differentiated thyroid carcinomas and many other human tumors (12).…”

Molecular Markers: From Diagnosis to Prognosis in 2013

“…Some variables are associated with a worse prognosis including advanced age, male gender, tumor size, extrathyroidal extension, race, lymph node metastasis, distant metastasis, impaired iodine uptake by the tumor/ metastasis, vascular invasion, familial history of WDTC, incomplete surgical excision and others [61][62][63]. Neck recurrence, usually in the form of regional lymph node metastases, occurs in up to 20 % of patients with low-risk PTC and 59 % of high-risk cases [64].…”