Histological Types Of Thyroid Carcinoma Research Articles

Histopathological Characteristics and Incidence of Thyroid Carcinoma in a Tertiary Care Hospital of Pakistan - A retrospective study

Background: Thyroid cancer is the most frequently occurring cancer of endocrine organs. From the past few decades, the prevalence of thyroid carcinoma is increasing generally and this has aroused the great public concern.Papillary thyroid carcinoma is primarily responsible for this high prevalence.The cases of other types of thyroid malignancies have remained stable over time. Aim: To analyze our institution-based trends in histopathological characteristics and incidence of thyroid carcinoma. Study Design: Retrospective study Place and duration: Pathology Department of Rai Medical College, Sargodha, from July 2017 to June 2022. Methodology: This study comprised of 56 cases of thyroid neoplasm diagnosed on biopsy. The main histologic types of thyroid carcinoma include papillary, follicular, medullary and anaplastic. Results: Of 374 thyroid lesions reviewed, 56 cases were malignant. Among these, PTC constituted about 43(76.78%) cases. There were 6(10.71%) cases of follicular ca followed by 5(8.92%) cases of medullary and 1(1.78%) case of anaplastic carcinoma. Practical implication: Unfortunately, the frequency of thyroid cancer in Pakistan is on the increaseandthe incidence of thyroid cancer in our country is difficult to measure due to the limitations of epidemiological statistics. Information regarding the geographic distribution of thyroid cancer is of great value for formulating epidemiologic hypothesis and for understanding the concepts of its risk factors. Such info is also valuable for making worldwide comparisons. Conclusion: Thyroid cancer was six times more frequent in females (female-to-male ratio 6:1). Most cases of PTC, follicular carcinoma and medullary carcinoma were in patients in the fourth decade of life then in third and fifth decade. However, anaplastic carcinoma was seen between 60 to 69 years of age. Keywords: Thyroid Neoplasms, Thyroid Cancer, Papillary, Thyroid Carcinoma, Anaplastic

Association of Programmed Death-Ligand 1 Expression with Aggressive Histological Types of Thyroid Carcinoma.

Immunohistochemical expression of programmed death-ligand 1 (PD-L1) has become a biomarker to predict the usefulness of cancer immunotherapy using PD-1/PD-L1 blockade in a variety of advanced-stage tumours. This emerging biomarker may serve to generate novel therapies for aggressive thyroid carcinoma (TC), which has not shown optimal results with existing treatments. The present study investigated the relevance of PD-L1 expression in aggressive histological types of TC compared with that found in less aggressive types. Surgically resected specimens were investigated, including 52 cases of TC consisting of 26 cases of aggressive histological types and 26 cases of less aggressive histological types. Immunohistochemical examinations were carried out on paraffin blocks of both groups using a mouse monoclonal primary antibody against PD-L1 (clone 22C3). PD-L1 expression was evaluated by calculating the tumour proportion score (TPS) in both groups. The results revealed a significant difference in the median TPS value of PD-L1 expression between the two groups. The TPS values were found to be higher in the group of aggressive histological types of TC compared with those in the group of less aggressive histological types. A significant difference in TPS value was also found for the extrathyroidal extension variable. In conclusion, the present study found a significant association between PD-L1 expression and the aggressive histological type of TC. In addition, a potential association between PD-L1 expression and the presence of extrathyroidal extension of TC was observed. These findings provide novel approaches for immunotherapy as a potential new treatment modality in patients with aggressive histological types of TC.

Predictive role of leptin and cyclin D1 in papillary thyroid carcinoma

IntroductionThyroid carcinoma is one of the most common malignancies originating from endocrine organs. Among various histological types of thyroid carcinoma, papillary thyroid cancer (PTC) is the most common. Obesity has long been recognized as a risk factor for tumorigenesis. Compelling evidence s

Candidate microRNAs as biomarkers of thyroid carcinoma: a systematic review, meta-analysis, and experimental validation.

Thyroid cancer is one of the most common carcinomas of the endocrine system with an increasing incidence. A growing number of studies have focused on the diagnostic and prognostic values of dysregulated microRNAs (miRNAs) in thyroid carcinoma. However, differences in the measurement platforms, variations in lab protocols, and small sample sizes can make gene profiling data incomparable. A meta‐review of the published studies that compared miRNA expression data of thyroid carcinoma and paired normal tissues was performed to identify potential miRNA biomarkers of thyroid carcinoma with the vote‐counting strategy. Two hundred and thirty‐six aberrantly expressed miRNAs were reported in 19 microRNA expression profiling studies. Among them, 138 miRNAs were reported in at least two studies. We also provided a meta‐signature of differentially expressed miRNAs between individual histological types of thyroid carcinoma and normal tissues. The experimental validation with qRT‐PCR analysis verified that the profiles identified with the meta‐review approach could effectively discriminate papillary thyroid carcinoma tissues from paired noncancer tissues. The meta‐review of miRNA expression profiling studies of thyroid carcinoma would provide information on candidate miRNAs that could potentially be used as biomarkers in thyroid carcinoma.

Serum Adiponectin And Insulin-Like Growth Factor 1 In Predominantly Female Patients With Thyroid Cancer: Association With The Histologic Characteristics Of The Tumor

Objective: Insulin-like growth factor (IGF)-1 and adiponectin have been proposed to contribute to the pathogenesis of different malignancies. However, data regarding their association with histologic characteristics of thyroid cancer are scarce. The main aims of the present study were the comparative evaluation of IGF-1, IGF-binding protein 3 (BP3), and adiponectin serum levels between different histologic types of thyroid cancer, as well as within specific histologic characteristics of the tumors.Methods: A total of 179 thyroid cancer patients (126 [70.4%] women) were recruited. A total of 129 (72.1%) had papillary thyroid carcinoma (including variants), 26 had follicular thyroid carcinoma (14.5%), and 24 had medullary thyroid carcinoma (13.4%). Parameters from history, physical examination, and thyroid histology were selected. Serum adiponectin, IGF-1, and IGF-BP3 were measured in fasting morning samples.Results: IGF-1, IGF-BP3, and adiponectin levels were similar among different histologic types of thyroid carcinoma, with a trend towards higher IGF-1 and IGF-BP3 levels in patients with intrathyroid invasion, compared to those without. In addition, ratios of IGF-1 to adiponectin (P = .012) and IGF-1 to (adiponectin × IGF-BP3) (P = .003), as well as type 2 diabetes (P = .001), were positively associated with tumor size.Conclusion: Although IGF-1, IGF-BP3, and adiponectin were not separately different between groups or within specific histologic lesions, when they were combined to produce IGF-1 to adiponectin and IGF-1 to (adiponectin × IGF-BP3) ratios, they were independently associated with tumor size. Future prospective studies are needed to evaluate whether these ratios could serve as prognostic markers of thyroid tumor aggressiveness.Abbreviations:CI = confidence intervalIGF-1 = insulin-like growth factor-1IGF-1R = insulin-like growth factor 1 receptorIGF-BP3 = insulin-like growth factor binding protein 3MTC = medullary thyroid carcinomaOR = odds ratioPTC = papillary thyroid carcinomaPTC-fv = papillary thyroid carcinoma-follicular variantT2DM = type 2 diabetes mellitus

BRAF mutations in thyroid tumors from an ethnically diverse group

BackgroundThe molecular etiology of thyroid carcinoma (TC) and other thyroid diseases which may present malignant precursor lesions is not fully explored yet. The purpose of this study was to estimate frequency, type and clinicopathological value of BRAF exon 15 mutations in different types of cancerous and non-cancerous thyroid lesions originating in an ethnically diverse population.MethodsBRAF exon 15 was sequenced in 381 cases of thyroid lesions including Hashimoto´s thyroiditis, nodular goiters, hyperplastic nodules, follicular adenomas (FA), papillary TC (PTC), follicular variant PTC (FVPTC), microcarcinomas of PTC (micro PTC; tumor size ≤ 1 cm), follicular TC (FTC), and non-well differentiated TC (non-WDTC).ResultsWe identified BRAF mutations in one of 69 FA, 72 of 115 (63%) PTC, seven of 42 (17%) FVPTC, 10 of 56 (18%) micro PTC, one of 17 (6%) FTC, and one of eight (13%) non-WDTC. Most of the cases showed the common V600E mutation. One case each of PTC, FVPTC, and FTC harbored a K601E mutation. A novel BRAF mutation was identified in a FA leading to deletion of threonine at codon 599 (p.T599del). A rare 3-base pair insertion was detected in a stage III PTC resulting in duplication of threonine at codon 599 (p.T599dup). Patients with PTC harboring no BRAF mutation (BRAFwt) were on average younger than those with a BRAF mutation (BRAFmut) in the PTC (36.6 years vs. 43.8 years). Older age (≥ 45 years) in patients with PTC was significantly associated with tumor size ≥ 4 cm (P = 0.018), vessel invasion (P = 0.004), and distant metastasis (P = 0.001). Lymph node (LN) involvement in PTC significantly correlated with tumor size (P = 0.044), and vessel invasion (P = 0.013). Of notice, taken the whole TC group, family history of thyroid disease positively correlated with capsular invasion (P = 0.025).ConclusionsOlder age is manifold associated with unfavorable tumor markers in our series. The K601E identified in a PTC, FVPTC, and FTC seems to be more distributed among different histological types of TC than previously thought. The T599del is a yet undescribed mutation and the rare T599dup has not been reported as a mutation in PTC so far.

Merged histological types of malignant thyroid tumor: experience and controversy

Malignant tumors of the thyroid that consist of merged histological types are a rare clinical entity, with an obscure pathogenesis and no consensus of opinion on nomenclature. Eight patients with merged histological types of thyroid malignant tumor at a single medical center were enrolled between January 1977 and December 2009. These patients were surgically treated and were followed postoperatively from 1 month to 34 years. Preoperative patient characteristics, B-type ultrasonography, computed tomography scan, thyroid function tests, postoperative pathology, immunohistochemistry, and prognosis data were collected. Merged histological types of thyroid malignant tumor accounted for 0.12% of all thyroid malignant tumors treated during this period. Preoperative imageology and laboratory data have no specific value toward diagnosis of merged histological types of thyroid malignant tumor. Merged histological types of thyroid carcinoma that had undergone radical resection in combination with hormonal therapy and I(131) radiotherapy achieved a satisfactory outcome, while other merged thyroid malignant tumors were usually associated with a poor prognosis. Prognosis depended on the highest grade among an individual group of malignant tumors.

Diffuse Sclerosing Variant Is a Major Subtype of Papillary Thyroid Carcinoma in the Young

Pediatric thyroid cancer differs from adult thyroid cancer in presentation and outcome. Pediatric thyroid cancer has a higher recurrence rate and greater percentage of lymph node and pulmonary metastasis. The clinicopathologic characteristics of pediatric thyroid cancer according to the histologic subtype have not been reported, however. In this study, we determined the histological subtypes of pediatric thyroid cancer and analyzed other clinicopathologic characteristics. All patients with thyroid cancer who were admitted to Severance Hospital, Seoul, South Korea, were retrospectively reviewed; their age was <20 years at diagnosis, and they were seen between January 1995 and August 2008. Sixty-eight patients were identified. The histologic types of thyroid carcinoma were papillary thyroid carcinoma (PTC) in 57 (83.8%), follicular carcinoma in 8 (11.8%), and poorly differentiated carcinoma in 3 (4.4%). There were 28 (41.2%) cases of diffuse sclerosing variant of papillary carcinoma (DSVPC), 26 (38.2%) of conventional PTC, 2 (2.9%) of follicular PTC, and 1 (1.5%) cribriform-morular PTC. In patients with PTC, there was a higher incidence of bilateral thyroid involvement (p = 0.003), extrathyroidal extension (p = 0.009), and lymph node involvement (p = 0.018), and lower recurrence-free survival (p = 0.032) in DSVPC than in non-DSVPC. Univariate regression analysis revealed that extrathyroidal extension (p = 0.025) and tumor size (p = 0.001) were positively associated with a shorter time to recurrence. DSVPC is a major subtype of PTC in the young.

Prognostic Factors in Papillary and Follicular Thyroid Carcinoma: Their Implications for Cancer Staging

Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) are two distinct histological types of thyroid carcinoma but have often been studied and staged as a collective group, known as differentiated thyroid carcinoma (DTC). However, this may not be an optimal approach to cancer staging. A total of 760 patients with DTC, comprising 589 (77.5%) with PTC and 171 with (22.5%) FTC, being managed at our institution from 1961 to 2001 were retrospectively reviewed. Their clinicopathological features, treatment modalities received, and postoperative outcome were analyzed. Both univariate and multivariate analyses were performed to identify prognostic factors related to cancer-specific survival (CSS) for PTC and FTC. There were statistically significant differences between PTC and FTC in terms of age >/=50 years at diagnosis (P = .040), tumor size (P < .001), lymph node metastases (P < .001), distant metastases (P < .001), extrathyroidal extension (P < .001), multifocality (P = .002), capsular invasion (P < .001), extent of thyroid resection (P < .001), radioiodine ablation (P < .001), and external-beam irradiation (P = .003). Although PTC and FTC had similar 10-year and 15-year CSS (P = .846), each possessed its own set of independent prognostic factors for CSS. Age at diagnosis and completeness of resection were independent prognostic factors in both PTC and FTC. There were marked differences in clinicopathologic features, treatment, and prognostic factors between the two histologic types of DTC. Different staging systems should be evaluated and validated for PTC and FTC individually in the future.

Endocrine cancer in Iran: Based on cancer registry system

A population-based registry of endocrine cancer cases in four Iranian provinces, was performed for the years 1996-2000. Patients in each province were grouped according to age, gender and tumor specifics (site, morphology, behavior) and the data was coded according to the international classification of diseases for oncology. Person-years of population at risk were calculated and the results were presented as incidence rates by sex, age, age specific rates and age standard rate (ASR) per 100,000 person-years, using direct method of standardization to the world population. A total of 319 cases of primary endocrine cancer were found and registered, including 313 cases of thyroid carcinoma and 6 cases of adrenal cancer. The thyroid carcinoma group cases consisted of papillary (82.7%), follicular (8.6%), medullary (7.0%) and anaplastic (1.6%) carcinomas. The ASR for thyroid carcinoma was 1.289 (0.627 for men, 1.59 for women), with the highest incidence rate in Kerman (ASR 1.643) and the lowest incidence rate in Golestan (ASR 0.735). For the 6 cases of adrenal cancer, 4 were neuroblastoma and 2 were pheochromocytoma. Iran was considered as an endemic, iodine-deficient area, until fairly recently. Iodinization of salt has been started about 12 years ago, in the nation. Considering the effect of improvement in the iodine intake in previously deficient communities, which is associated with an increase in the incidence of papillary carcinoma compared to other histologic types, the frequency and distribution of histologic types of thyroid carcinoma was closer to what can be seen in iodine-rich areas.

Estrogen Receptors (α and β) and 17β-Hydroxysteroid Dehydrogenase Type 1 and 2 in Thyroid Disorders: Possible In Situ Estrogen Synthesis and Actions

Both epidemiological and experimental findings suggest the possible roles of sex steroids in the pathogenesis and/or development of various human thyroid disorders. In this study, we evaluated the expression of estrogen receptors (ER) α and β in normal thyroid glands (N = 25; female: n = 13, male: n = 10, unknown: n = 2) ranging in age from fetus to adult. Furthermore, using immunohistochemistry, we investigated the expression of ERα and β in 206 cases of thyroid disorders, including 24 adenomatous goiters, 23 follicular adenomas, and 159 thyroid carcinomas. In addition, we also studied the mRNA expression of ERα and β and 17β-hydroxysteroid dehydrogenase Type 1 and 2, enzymes involved in the interconversion between estrone and estradiol, using reverse transcription polymerase chain reaction (RT-PCR), in 48 of these 206 cases (10 adenomatous goiters, 10 follicular adenomas, and 28 papillary thyroid carcinomas) in which fresh frozen tissues were available for examination to further elucidate the possible involvement of intracrine estrogen metabolism and/or actions in thyroid disorders. ERα labeling index, or percentage of cells immunopositive for ERα, was significantly higher in adenomatous goiter (14.2 ± 6.4), follicular adenoma (13.4 ± 5.1), and thyroid carcinoma (16.4 ± 2.1) than in normal thyroid gland (0; P < .05). Few follicular cells were positive for ERα in normal thyroid glands. In papillary carcinoma, ERα labeling index was significantly higher in premenopausal women (28.1 ± 4.5) than in postmenopausal women (14.2 ± 2.9) and in men of various ages (7.6 ± 2.7; P < .05). In other histological types of thyroid carcinoma, no significant correlations were detected. ERβ immunoreactivity was detected in both follicular and C-cells of normal thyroid glands, including those in developing fetal thyroid glands. In addition, ERβ immunoreactivity was detected in the nuclei of various thyroid lesions. But no significant correlations were detected between ERβ labeling index and clinicopathological findings including age, menopausal status, gender, and/or histological type of thyroid lesions. 17β-hydroxysteroid dehydrogenase Type 1 expression was detected in 31/48 (64.0%) of the cases examined, whereas Type 2 was detected only in 3/46 (6.3%) of all the cases examined. These results demonstrated that estrogens may influence the development, physiology, and pathology of human thyroid glands, and these effects, especially through ERα, may become more pronounced in neoplasms, particularly in papillary carcinoma arising in premenopausal women.

Avances en el diagnóstico de los tumores otorrinolaringológicos

In the present study we review ENT tumor pathology in childhood. Only the most salient aspects are emphasized and the variety of entities reviewed was restricted. Molecular biology techniques reveal infection by human papilloma virus (types 6 and 11) in 50 % of papillomas, while immunohistochemical techniques are less effective in papilloma virus detection. The myofibroblastic nature of nasal angiofibroma has been demonstrated and its incidence is 25 times more frequent in patients with familial polyposis of the colon. Overexpression of p53 occurs in the initial stages of nasopharyngeal carcinoma, while overexpression of c-myc is correlated with an unfavorable prognosis. Recently, olfactory neuroblastoma has been shown not to express the protein product of the MIC-2 gene (antibody 12E7), thus the hypothesis that it could be a member of the Ewing tumor family (neuroectodermal peripheral tumors) has not been confirmed, although it is a primitive neural tumor. The head and neck rhabdomyosarcoma with the best prognosis is that located in the orbit, and cytogenetic studies have shown chromosomic translocation t(2;13) in 50 % of these childhood tumors when they are of the alveolar-type, while trisomy of chromosome 2 or 20 is more characteristic of the embryonic-type. Currently, any classifying features of ENT lymphomas must be based on the Revised European-American Classification of Lymphoid Neoplasms (REAL). Papillary and medullary carcinomas are the most common histological types of thyroid carcinoma in childhood. Alterations in ret/PTC play a significant role in the pathogenesis of both.

Demonstration and Diagnostic Significance of Pro-Gastrin-Releasing Peptide in Medullary Thyroid Carcinoma

The expression of pro-gastrin-releasing peptide (proGRP) in medullary thyroid carcinoma (MTC) and other histological types of thyroid carcinoma was studied by an immunohistochemical technique, using polyclonal anti-proGRP antiserum. Immunoreactivity for proGRP was detected exclusively in MTC (n = 7); other histological types (n = 12) were all negative for proGRP. In addition, serum proGRP levels were elevated in patients with primary or recurrent MTC (n = 3), and they changed in parallel with serum calcitonin (CT), and carcinoembryonic antigen (CEA). These results show that proGRP, which is considered to be a specific marker for small-cell lung carcinoma, may be also a potential tumor marker for MTC, in addition to CT and CEA.

Descriptive epidemiology of thyroid cancer in Los Angeles County, 1972-1995.

To examine the descriptive epidemiologic features of incident thyroid cancers diagnosed among Los Angeles County residents between 1972 and 1995. The Los Angeles County/University of Southern California Cancer Surveillance Program (CSP) collected data on 8820 newly diagnosed thyroid cancer of cases occurring in Los Angeles County. Average annual age-adjusted incidence rates were calculated to study the epidemiology of each of the major histologic types of thyroid carcinoma. For all races combined, the age-adjusted incidence rates were 2.5 per 100,000 males and 6.0 per 100,000 females. Differences in incidence by ethnicity were particularly striking, with Filipinos demonstrating the highest incidence rates (4.44 per 100,000 males, 11.3 per 100,000 females). Over the 23-year period, thyroid cancer incidence rates increased 1.5% per year for males and 1% per year for females. By histology, papillary carcinoma rates increased over time and follicular carcinoma rates decreased. Non-Spanish surnamed white men employed in certain white-collar occupations and radiologic technicians were at greater risk of thyroid cancer. Additional research on the epidemiologic risk factors for thyroid cancer, particularly for gender and ethnicity, is needed to explain the marked elevated incidence rates among females and the Filipino population in Los Angeles County.

Prognostic factors for thyroid carcinoma. A population-based study of 15,698 cases from the Surveillance, Epidemiology and End Results (SEER) program 1973-1991.

A number of prognostic factors for thyroid carcinoma have been identified, including sociodemographic characteristics, such as age and gender, and tumor characteristics, such as histology and stage. The relative importance of these factors as independent predictors of survival for patients with papillary, follicular, anaplastic, and medullary thyroid carcinoma has been extensively studied but remains uncertain. The authors used data collected by the Surveillance, Epidemiology and End Results (SEER) program of the National Cancer Institute between 1973 and 1991 to investigate prognostic factors for each of the major histologic types of thyroid carcinoma in a population-based patient series and to assess the effect of these factors as predictors of survival. Both tumor and sociodemographic characteristics were independently associated with survival. Patients with papillary carcinoma had the highest 10-year relative survival (0.98), followed by those with follicular carcinoma (0.92) and medullary carcinoma (0.80). Anaplastic tumors had the lowest 10-year relative survival (0.13). Stage at diagnosis and differentiation status were strong independent prognostic factors for each histologic type. Advanced stage at diagnosis was a stronger prognostic factor for medullary carcinoma than for other histologic types. Increasing age was associated with lower relative survival for each histologic type. Gender, marital status, and ethnicity were significant, but weaker, predictors of survival. Survival varied markedly among patients with different histologic types of thyroid carcinoma. Stage at diagnosis and tumor differentiation were important prognostic factors for each histologic type. Age at diagnosis was a stronger predictor of survival for patients with follicular and medullary carcinoma than for patients with papillary carcinoma.

Combined chemotherapy with bleomycin, adriamycin, and platinum in advanced thyroid cancer

Twenty-two advanced consecutive thyroid cancer patients with varying histologies were treated with the so called BAP regime which consisted of bleomycin (B) 30 mg a day for three days, adriamycin (A) 60 mg/m2 iv in day 5, and cisplatinum (P) 60 to mg/m2 iv in day 5. Patients with progressive, symptomatic recurrent or disseminated disease unresponsive to hormonal and/or isotopic treatment were eligible. Nine patients had an objective response: two long-lasting complete and seven partial responses were observed out of 21 evaluable patients. Stable disease was observed in four additional patients. The median duration of response was 12 months (range, 6-29). The total series experienced a median survival of 11 months (range, 1 to 57), with 2 patients actually disease free. Several histologic types of thyroid carcinoma responded, but the best responses were observed in medullary and anaplastic giant-cell carcinomas. Toxicity was reversible in all but one patient. Of the patients failing on BAP chemotherapy three responded to a four drug second line combination containing vincristine, fluorouracil, BCNU and methotrexate. BAP regime can achieve reasonable palliation, and probably increases survival, in poor-prognosis thyroid cancers.

New subgrouping of small thyroid carcinomas.

Clinicopathologic findings on small thyroid carcinomas measuring 10 mm or less in diameter were analyzed in 78 thyroidectomied cases. The authors divided small thyroid tumors into two subgroups according to diameter: 0 less than or equal to 5 mm (classified as minute carcinoma) and 5 less than 0 less than or equal to 10 mm (classified as tiny carcinomas). Characteristics including sex, age, histologic type, extrathyroid invasion, and lymph node metastasis were examined in each subgroup. In patients with minute carcinoma, very few incidences of extrathyroid invasion and lymph node metastasis were found. However, these involvements, especially lymph node metastasis, were found more frequently in patients with tiny carcinoma. The incidence of cervical lymph node metastasis was 13% in minute carcinoma and 59% in tiny carcinoma. (P less than 0.01). These findings suggest the need for more careful observation and treatment of tiny carcinomas, especially with respect to lymph node metastasis. In accordance with World Health Organization (WHO) classification, the histologic types of thyroid carcinoma were classified into papillary and follicular carcinomas. The papillary carcinoma and follicular carcinoma ratios were compared between the two subgroups. The discovery rate of follicular carcinoma was significantly higher in minute carcinoma than in tiny carcinoma (P less than 0.005). This suggests that the papillary carcinoma/follicular carcinoma ratio (p/f) increases as the size of the carcinoma increases, and that follicular carcinoma is the "seed," or initial form, of thyroid cancer. The female-male ratio in small thyroid cancer suggests that there is no sex difference in carcinogenesis but that there is more probability for cancer development in the thyroid in women.

Carcinoembryonic antigen in thyroid cancer.

Serum levels of carcinoembryonic antigen (CEA) were measured by radioimmunoassay in 35 patients affected by various histological types of thyroid carcinoma: 9 papillary, 7 follicular, 4 undifferentiated, 15 medullary. All patients with nonmedullary thyroid carcinoma were studied preoperatively. No patient with follicular thyroid carcinoma showed CEA levels above normal limits ( 320 ng/ml) were found in 2 of the 4 patients with medullary thyroid carcinoma studied before treatment and in the 4 patients (>320->320- 23-15 ng/ml) studied after total thyroidectomy alone; 3 of them had distant metastases. High levels (65-50-13 ng/ml) were also found in 3 other patients without metastases studied after total thyroidectomy plus radiotherapy. Thyroidectomy plus radiotherapy rapidly decreased CEA levels (from >320 to 20 ng/ml) in a patient without metastases, while the same treatment failed to reduce CEA levels consistently (from > 320 to 112 ng/ml) in a patient with distant metastases. The data suggest than high levels of CEA are frequent but not constant in patients with medullary thyroid carcinoma; in other histological types CEA is present only in sporadic cases. Since in the positive cases of medullary thyroid carcinoma CEA levels seem to be related to the effectiveness of the therapy, CEA assay may be useful in the management and follow up of this tumour.

Thyroid cancer in an iodide rich area: a histopathological study.

A comparison of the incidence of the different histological types of thyroid carcinoma in an area of high dietary iodide and an area of normal iodide intake has been made. The areas chosen were Iceland and the region of Northeast Scotland centred on Aberdeen; both areas have clearly defined populations served by a single pathology laboratory. All definite and dubious thyroid carcinomas from both regions were examined and classified by the same two pathologists. The age-specific incidence rates for papillary carcinoma in surgical specimens in both areas rose with age; they were five times higher in Iceland (high iodide area) than in Northeast Scotland. The numbers of follicular carcinomas were small, and this tumor was relatively less frequent in Iceland than Aberdeen. These findings, together with the known high relative frequency of follicular carcinoma and low frequency of papillary carcinoma in areas of endemic goitre, lead to the suggestion that the incidence of papillary carcinoma and follicular carcinoma are separately influenced by dietary iodide, papillary carcinoma being high in areas of high iodide intake and low in areas with low dietary iodide. No evidence to implicate lymphocytic thyroiditis, radiation or genetic factors in the genesis of thyroid carcinoma in Iceland or Northeast Scotland was found in this study. Undifferentiated carcinoma was about three times as common in Iceland as in Northeast Scotland. Malignant lymphoma of the thyroid was suprisingly common in Northeast Scotland, possibly related to the high frequency of thyroiditis found in this region. These studies suggest that the incidence of different histological types of thyroid malignancy is influenced by different etiological factors. They also provide support for the subdivision of thyroid malignancy into these different types, and for the general importance of accurate histological typing in cancer epidemiology.

Anaplastic carcinoma of the thyroid: evaluation of postoperative results.

IT IS well known that there is a marked difference in the rate of growth and clinical behavior of the various histologic types of thyroid carcinoma. The largest histologic group, namely papillary carcinomas, consists of slowly growing neoplasms whose natural history is now well understood. The role of the surgeon in the treatment of this form of carcinoma is well established. Extensive local surgical procedures may be combined with dissection of cervical lymph nodes, or even with radical dissection of mediastinal lymph nodes. Additional histologic types of thyroid carcinoma, more malignant than the papillary form but of relatively slow growth, include the more or less circumscribed or encapsulated carcinoma variously called “malignant adenoma” or follicular and alveolar carcinoma. In this group, metastasis may occur by lymphatics to regional nodes or by the blood stream, particularly to bone. Hurthle-cell carcinomas, frequently encapsulated, make up a fairly well recognized histologic group, as do solid a...