[[Molecular pathology of endocrine tumors] [Spanish]

Endocrine neoplasms exhibit the same general type described abnormalities in most of malignant tumors. Many of these changes were initially described hereditary syndromes associated with tumors, and have been confirmed also in sporadic tumors.<br>Like most epithelial neoplasms, malignant transformation is the result of the accumulation of multiple genetic defects that determine the malignant cells do not respond and are independent of normal growth signals. Genetic alterations affecting oncogenes, tumor suppressor genes and gene repair. The molecular characterization of these defects has allowed to identify specific molecular mechanisms in these tissues and, in some cases, provide diagnostic and prognostic information very useful. The identification of germline mutations associated with multiple endocrine neoplasia syndromes types 1 and 2 has allowed the development of DNA tests to assess individuals at risk. In patients with medullary thyroid carcinoma, early thyroidectomy can be performed on the foundation provided by the analysis of DNA mutations (oncogene RET) when the tumor is still hidden and is curable.<br>The most frequent alterations have been associated with endocrine neoplasms are:<br>1. Genetic alterations associated with tumor initiation:<br>a. RET, RAS, fusion genes in thyroid neoplasms (RET / number in papillary carcinoma, PAX8/PPARg in follicular neoplasms).<br>b. Enzymes of the mitochondrial respiratory chain (SDHB/SDHD in paragangliomas, pheochromocytomas).<br>c. Enzymes for DNA replication and repair (Carney triad).<br>2. Genes associated with tumor progression: TP53, RB1.<br>3. Cell immortalization: reactivation of telomerase.