Familial papillary carcinoma of the thyroid

Malignant tumors in families of thyroid cancer patients

A case-control study comprised 177 patients with various types of thyroid cancer and the same number of hospital controls individually matched by age, sex and place of residence. Malignant tumors were more frequent among first and second degree relatives of cases as compared to controls. The odds ratio (95% confidence interval) was 2.43 (1.33-4.44) and 5.33 (1.77-16.01) respectively. The most frequent were cancers of uterus and stomach with odds ratio of 6.00 (1.61-22.36) and 9.00 (1.64-49.35). Thyroid cancer was present only in first-degree relatives of two cases and none of controls.

Familial nonmedullary thyroid carcinoma: a meta-review of case series

Familial occurrence of nonmedullary thyroid carcinoma is extremely rare but this has been increasingly recognized over the recent years. Earlier reports of such occurrence were primarily confined to individuals with previous radiation exposure, history of familial adenomatous polyposis (Gardner's syndrome) or multiple hamartomas (Cowden's syndrome), or monozygotic twins. The author reviews 15 case reports/series of familial nonmedullary thyroid carcinoma available in the literature involving kindreds with no obvious associated pathogenetic factors as mentioned above. There were a total of 87 kindreds with 178 affected individuals available for analysis, with a male to female ratio of 1:2.2. The modal age group at diagnosis was 30-39 years in both gender groups. Papillary thyroid carcinoma constituted 91% of the cases, followed by follicular (6%) and anaplastic (2%) varieties. There was one case (0.5%) each of combined papillary and medullary thyroid carcinoma and Hurthle cell carcinoma, respectively. Six of the 15 series observed that patients with familial history generally have more aggressive tumour characteristics compared to the sporadic counterparts. The incidences of multifocality, local invasion, and distant metastases at diagnosis were 49, 32, and 5%, respectively. The incidences of locoregional recurrence, distant metastases, and deaths were 29, 10, and 5.4%, respectively, at a mean follow-up period of 11 years. The actual prognostic outcome of familial nonmedullary thyroid carcinoma is still unclear in view of the limited clinical data. Although several authors have advocated an aggressive approach in managing these patients, no conclusion can be reached on the basis of this review to support this position. The author recommends that patients with familial disease should be treated according to the disease stage and other risk factors, similar to those with spontaneously occurring well-differentiated papillary or follicular thyroid carcinomas. In addition, one might consider and perform follow-up of first-degree relatives with similar degree of caution as patients who have undergone head and neck irradiation in childhood.

Risk factors for thyroid cancer

The potential risk factors for thyroid carcinoma development include genetic predisposition, exposure to therapeutic or environmental ionizing radiation, residence in areas of iodine deficiency or excess, history of preexisting benign thyroid disease, as well as hormonal and reproductive factors. In this review, we analyze some of the epidemiological data, as well as the possible molecular mechanisms by which certain environmental and genetic factors might predispose to thyroid tumorigenesis. (c) 1997, Elsevier Science Inc. (Trends Endocrinol Metab 1997; 8:20-25).

Thyroid cancer: a review of treatment and follow-up

The importance of thyroid cancers far exceeds their frequency, since they are uncommon tumours accounting for only 1% of all malignancies and for even smaller proportion of cancer deaths (0.2%). A variety of distinct tumour types arise in the thyroid gland, with variable natural histories resulting from different rates of growth and biological aggressiveness. The long natural history of the majority of thyroid neoplasms imposes a commitment for long-term follow-up and stresses the importance of planning treatment so as to avoid delayed complications that impair the quality of life of patients. The management of thyroid cancer is multidisciplinary, requiring consultation and active intervention by surgeons, endocrinologists and radiotherapists. Surgery is of paramount importance in the successful eradication of the tumours while radioiodine offers a unique therapeutic approach. Treatment must be strongly influenced by consideration of prognostic variables.

Sisters with familial adenomatous polyposis affected with thyroid carcinoma, desmoid tumour and duodenal polyposis

After prophylactic surgery for colonic polyposis, upper gastrointestinal cancer and desmoid tumour are the main causes of death in patients with familial adenomatous polyposis (FAP). Two sisters with FAP who developed multicentric carcinoma of the thyroid, desmoid tumour and duodenal polyposis are presented.

Towards understanding the molecular basis of thyroid cancer

Cancer is a multistep phenomenon and multiple genetic lesions are involved in the emergence of the cancerous lesion. This has best been demonstrated in colonic cancer. The authors review their work and that of others highlighting what is known about thyroid cancer. They implicate ras mutations predominantly in follicular carcinoma, rearrangement of the ret proto-oncogene in papillary carcinoma and the tumor suppressor genes p53 and retinoblastoma gene product in all stages of thyroid carcinoma. They find a low rate of ret proto-oncogene rearrangement in the Saudi population (>5%) as compared to elsewhere in the world (20%). They find TSH receptor message abundance to be predictive of prognosis in thyroid cancer patients. Lastly, they examine whether the abundance of the anti-metastatic gene nm23 message abundance negatively correlated with the tendency of thyroid tumors to metastasize and find that not to be the case in thyroid carcinoma. The study of oncogenes and tumor suppressor genes in the pathogenesis of thyroid cancer is in its infancy; however, rapid progress is being made in identifying genes participating in malignant thyroid cell transformation.

Familial adenomatous polyposis associated thyroid carcinoma: a distinct type of follicular cell neoplasm

Thyroid carcinoma has been described as occurring more frequently than expected in association with familial adenomatous polyposis. The histology of these cases has not been described in detail, although the reported cases were usually diagnosed as papillary carcinoma. We now report the pathological features of four cases of thyroid carcinoma associated with familial adenomatous polyposis, and review the findings in the literature. The tumours in these four cases were all of follicular cell origin as shown by thyroglobulin immunohistochemistry. In three they were multifocal. The tumours showed some features of papillary carcinoma--grooved nuclei and papillary architecture, but these were not consistent. They also showed features that were unusual for papillary carcinoma--a cribriform pattern and solid areas with spindle cell component. Commonly the tumours combined both patterns. A review of the reported cases of thyroid cancer associated with familial adenomatous polyposis showed that they also were commonly multifocal and occurred predominantly in young women. When the histology was adequately reported or illustrated it was, in most instances, consistent with the findings in our own cases. We therefore suggest that these thyroid tumours form a distinct type with some unusual features. Clearly it is likely that the APC gene is associated with their pathogenesis, and that other factors contribute to the predominantly female incidence in this as in sporadic tumours. Six of 63 reported cases showed metastasis or died from thyroid carcinoma. In a number of cases the tumours presented before the familial adenomatous polyposis was recognized. The findings of these unusual histological features in a thyroid tumour, and particularly of multicentricity, should alert the pathologist to the possibility of familial adenomatous polyposis with its implications for family screening. The tumours are often well demarcated but, because of the multicentricity, total thyroidectomy should be advocated.

Evidence against involvement of APC mutation in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is one of several tumours associated with familial adenomatous polyposis (FAP), an inherited tumour syndrome which appears to result from germ-line mutation of the APC tumour suppressor gene. Here we investigate the possibility that somatic mutation of APC might play a role in sporadic PTC. 16 cases of PTC together with matched normal tissue were examined by single-strand conformation polymorphism (SSCP) analysis, concentrating on the mutation cluster region (MCR) of the APC gene (codons 1286-1513). No evidence of mutation was observed in any sample. We conclude that APC mutation, at least in the MCR, is not a significant causal mechanism in sporadic PTC.

Constitutional ring chromosomes and tumour suppressor genes

The types of malignancy reported in carriers of constitutional ring chromosomes r(11), r(13), and r(22) are concordant with the chromosomal assignment of tumour suppressor loci associated with Wilms' tumour, retinoblastoma, and meningioma. It is suggested that the somatic instability of ring chromosomes may play a role in this association and that constitutional ring chromosomes may be a source for mapping of tumour suppressor loci with the potential for covering most or all of the human genome. The hypothesis predicts the presence of a locus on chromosome 10 associated with follicular carcinoma of the thyroid, in line with previous cytogenetic findings of rearrangements involving chromosome 10 in thyroid tumours, and a locus on chromosome 22 associated with testicular cancer. Development of neurofibromatoses (NF) that do not fulfil the clinical criteria of neurofibromatosis type 2 (NF2) in carriers with r(22) suggests either the presence of an additional NF locus on chromosome 22 or that ring chromosome mediated predisposition to somatic mutation of a specific tumour suppressor may be associated with atypical development of features usually associated with germline mutations.

Second malignancies in thyroid cancer patients: a population-based survey of 3658 cases from Norway

In a population-based survey of 3658 thyroid cancer patients diagnosed in Norway during 1955-85, a total of 200 cases of second malignancies were observed (30,414 person-years, mean follow-up 8.4 years). Male patients had a significantly increased incidence of urogenital cancer [standardised incidence ratio (SIR) = 1.96, 95% confidence interval (CI) 1.4-2.7], including cancer of the testis (SIR = 11.8, 95% CI 3.2-30.1) and urinary bladder (SIR = 3.0, 95% CI 1.5-5.2). The occurrence of malignant melanoma was also increased among males (SIR = 4.2, 95% CI 1.4-9.7). This apparent association with urogenital cancers among males at the present time cannot be explained, although increased surveillance as well as specific aetiological factors should be considered.

Familial papillary carcinoma of the thyroid

A 38-year-old woman had bilateral papillary thyroid carcinoma. Her brother and mother also had papillary thyroid carcinoma. The literature on familial papillary thyroid carcinoma is reviewed briefly.

Evaluation of thyroid nodules

The first consideration in evaluating the thyroid nodule is whether it is functioning and causing hyperthyroidism. Autonomous nodules should be treated with either surgery or I-31, with surgery favored due to the possibility, although small, of malignancy. Thyroid scans are no longer recommended during the initial evaluation of the thyroid nodule. Ultrasound is useful in determining the size of the nodule and whether it is multinodular thyroid disease, but it cannot detect thyroid cancer. Fine needle aspiration biopsy is currently the procedure of choice for evaluating all thyroid nodules. For accuracy of the cytological analysis, it is important that adequate tissue samples be obtained. False negative findings are of most concern to the clinician and occur in 2-10% of reported fine needle aspiration biopsy series. Nodules thought to be benign will need continued follow-up.

Cytogenetic analyses of three papillary carcinomas and a follicular adenoma of the thyroid

Cytogenetic data of three papillary carcinomas and a follicular adenoma using direct preparations or cell cultures or both after 7 to 60 days in vitro are presented. Although karyotype of the follicular adenoma proved completely normal, in each of the three papillary carcinomas a modal chromosome number in the diploid range and a deleted 11q were observed. In case 1 the del(11)(q23) was associated with rearrangement of chromosome 1 and other marker chromosomes. Our results suggest that 11q deletion may be specific for papillary carcinoma of the thyroid.

Papillary carcinoma of the thyroid: additional evidence in support of a familial component

Although a higher incidence of medullary carcinoma of the thyroid is well known to occur in families with syndromes of multiple endocrine neoplasia (MEN II and III), an epidemiologic familial component has only very rarely been ascribed to papillary carcinoma. In this report we describe a mother and daughter presenting with neck masses at an early age and subsequently found to have metastatic papillary thyroid carcinoma documented on pathology following thyroidectomy. The occurrence of the neoplasm at an advanced stage in closely related individuals early in life suggests that underlying genetic factors may predispose to this malignancy. Familial papillary carcinoma of the thyroid may have a hereditary basis independent of its association with the syndromes of multiple polyposis and of multiple hamartomas, and thus may represent a new entity with characteristics which distinguish it as a distinct subset of the more common disease.

Papillary thyroid carcinoma in Iceland. A study of the occurrence in families and the coexistence of other primary tumours

This paper presents evidence from Iceland which indicates that papillary thyroid carcinoma occurs in certain families more often than expected. Thyroid carcinoma was also seen to coexist with some other cancer types more often than expected. We studied all families (n = 373) with papillary thyroid carcinoma diagnosed between 1955 and 1984 in Iceland. Familial papillary carcinoma occurred in 3.8% of these families. This frequency was higher than expected but not significantly increased. Second primaries in women, and especially the incidence of kidney and breast cancer, were significantly increased. Cancer of the kidney and CNS tumours were significantly increased in propositi when both sexes were taken together. No increase in the incidence of other malignancies was observed in first degree relatives of patients with papillary thyroid carcinoma.

Solitary thyroid nodule: diagnosis and management

Thyroid nodules are common. Most are benign lesions since clinically important thyroid carcinoma is a relatively rare disease. The most sensitive and specific test for the diagnosis of thyroid cancer is fine-needle aspiration biopsy, but its diagnostic accuracy depends upon whether or not one excises all suspicious nodules, thus including them as correctly diagnosed. Nevertheless, fine-needle aspiration biopsy is the most sensitive, specific, and cost-effective test for thyroid cancer. Therapy depends upon the cause of the thyroid nodule.

The human inactivated X chromosome folds in early metaphase, prometaphase, and prophase

The inactivated X chromosome has a site of unusually frequent folding in region Xq1, whereas a fold in Xq1 is uncommon on the active X. We investigated the pattern of X chromosome folding in high-resolution GTG- and RBG-stained preparations from four women. In early metaphase cells, slightly more than 50% of late-replicating Xs folded at Xq1----Xq21, compared with about 6% of early replicating Xs. The late-replicating X folded in about 80% of prometaphase cells; the early, in only about 14% of these cells. and the late-replicating X folded in 19 of 20 prophase cells. Occasionally, one X had an omega-shaped loop or apparent physical connection between Xq13 and Xq21.1. It is possible that a segment of Xq1 never completely uncoils and may help to provide continuity for the Barr body from one interphase to the next.