Familial Thyroid Carcinoma

Abstract

Thyroid carcinomas derived from follicular cells are the most common endocrine malignancies, and papillary thyroid carcinoma (PTC) is the most common type. Although, the majority of papillary and follicular thyroid carcinomas (FTCs) are sporadic, familial forms have been described in recent years. Familial syndromes are classified into familial medullary thyroid carcinoma and familial nonmedullary thyroid carcinoma. Multifocal papillary carcinoma is the most frequent presentation of familial nonmedullary thyroid carcinoma, and based on clinico-pathologic findings it is divided into 2 groups. The first includes familial syndromes characterized by a predominance of nonthyroidal tumors, such as familial adenomatous polyposis, PTEN-hamartoma tumor syndrome, Carney complex type 1, and Werner syndrome. The second group includes familial syndromes characterized by a predominance of NMTC, such as pure familial (f) PTC with or without oxyphilia, fPTC with papillary renal cell carcinoma, and fPTC with multinodular goiter. Medullary thyroid carcinoma is derived from calcitonin-producing C cells. The familial form accounts for 20% to 25% of cases, and is usually a component of multiple endocrine neoplasia (MEN) IIA or IIB, or presents as pure familial medullary thyroid carcinoma syndrome. C-cell hyperplasia is the precursor lesion of these heritable syndromes. Some characteristic morphologic findings should alert the pathologist of a possible familial cancer syndrome, which may lead to further molecular genetic evaluation.

Familial Papillary Thyroid Carcinoma: A Retrospective Analysis

“…It had been reported that the familial form of the disease has a greater incidence of cervical nodal metastases [3, 20–22], but we did not find any such increase. The multifocal nature of the disease was a very common finding in all of our cases (present in 52.2 to 65.5%), as was the presence of bilateral disease in all groups, but there were no significant differences seen between the familial and sporadic cases; a higher incidence of multifocality has been reported in certain series [6, 7, 14, 20, 27]. We did not see a trend to a larger size of the primary tumour in the familial cases nor, somewhat surprisingly, any difference in the finding of vascular or lymphatic invasion by tumour.…”

“…Hence the term familial papillary thyroid cancer (FPTC) is used in this paper. None of the established FPTC families had any evidence of additional tumours or clinical features to suggest the presence of a familial syndrome [18, 27, 28] characterized by a predominance of nonthyroidal tumours, for example, familial adenomatous polyposis, PTEN-hamartoma syndrome, Carney complex, and so forth. This study was approved by the Ethics Review Board for Human Research at the University of Western Ontario.…”

Familial Follicular Cell-Derived Thyroid Carcinoma

“…Multiple adenomatous nodules in a background of lymphocytic thyroiditis and/or C-cell hyperplasia are distinctive findings in this syndrome. Pathologists should notify clinicians of the possibility of PHTS (Dotto and Nosé, 2008). …”

“…These include familial adenomatous polyposis (FAP), Cowden syndrome (CS), Werner syndrome, Carney complex (CNC), and Pendred syndrome (Dotto and Nosé, 2008; Nosé, 2008; Vriens et al, 2009). …”

“…A classification of familial follicular cell thyroid cancer associated with hereditary syndromes (Dotto and Nosé, 2008; Nosé, 2008) is shown in Table 1. The inheritance, gene involved, and risks of familial cancer syndromes for developing thyroid cancer are also shown in Table 1.…”