Glandular patterns in a thyroid carcinoma with insular and anaplastic features: a case with possible implications for the classification of thyroid carcinomas

Age as a prognostic factor in anaplastic thyroid cancer

Background. Anaplastic thyroid cancer (ATC) is one of the tumors with the shortest survival in human medicine. Aim. The aim was to determine the importance of age in survival of patients with ATC. Material and Methods. We analyzed the data on 150 patients diagnosed with ATC in the period from 1995 to 2006. The Kaplan-Meier method and log-rank test were used to determine overall survival. Prognostic factors were identified by univariate and multivariate Cox regression analysis. Results. The youngest patient was 35 years old and the oldest was 89 years old. According to univariate regression analysis, age was significantly associated with longer survival in patients with ATC. In multivariate regression analysis, patients age, presence of longstanding goiter, whether surgical treatment is carried out or not, type of surgery, tumor multicentricity, presence of distant metastases, histologically proven preexistent papillary carcinoma, radioiodine therapy, and postoperative radiotherapy were included. According to multivariate analysis, besides surgery (P = 0.000, OR = 0.43, 95% CI = 0.29-0.63), only patients age (P = 0.023, OR = 0.68, 95% CI = 0.49-0.95) was independent prognostic factor of favorable survival in patients with ATC. Conclusion. Age is a factor that was independently associated with survival time in ATC. Anaplastic thyroid cancer has the best prognosis in patients younger than 50 years.

Anaplastic thyroid carcinoma in a young woman: a rare case of survival

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is rare but one of the most aggressive human cancers. It carries a dismal prognosis with average survival of 6 months. It is characteristically diagnosed in patients older than 60 years. We report the case of a young patient with ATC, in whom disease-free survival exceeds 2 years, and review the related literature.

SUMMARY

A 26-year-old woman presented with a rapidly growing anterior neck mass. A neck computed tomography scan showed a 3.5-cm left thyroid mass extending into the lateral neck. Fine-needle aspiration biopsy showed a malignant tumor. A subsequent core biopsy showed an undifferentiated epithelial carcinoma. A total thyroidectomy and left modified radical neck dissection were performed. Histopathology and immunohistochemical analysis confirmed an ATC. Postoperatively, the patient received radiation with concurrent chemotherapy. Serial follow-up imaging studies showed no evidence of residual or recurrent disease or metastases, and patient remains alive, free of disease, over 2 years.

CONCLUSION

ATC is usually a disease of the elderly but should be considered in the differential diagnosis of any patient who presents with a rapidly enlarging anterior neck mass. A rapid and thorough investigation should be initiated. This unusual case highlights that this aggressive thyroid cancer may occur in the young. It also emphasizes the role of aggressive surgery, if resectable.

Thyroid Carcinoma with Insular Component: Report of Three Cases with Different Clinical Pictures

Insular carcinoma of the thyroid is situated morphologically and biologically in an intermediate position between the well-differentiated and undifferentiated tumors and presents a variable clinical course in a widely heterogeneous spectrum. The present cancer staging system (TNM) for thyroid cancer considers differentiated and undifferentiated tumors while ignoring this intermediate type, which is also called poorly differentiated tumor. In addition to the limited data on this rare disease, some poorly differentiated thyroid tumors contain differentiated cancer areas at various rates. These factors may cause difficulties in estimating disease aggressiveness and prognosis. To solve this problem, various microscopic and immunohistochemical parameters can be assessed. In this paper we describe 3 patients affected by thyroid carcinoma with an insular component, who presented different clinical pictures. When these cases were examined, the TNM system failed in stage grouping for poorly differentiated thyroid tumors. Case 1 and case 2 had similar clinical stages according to the TNM staging system for differentiated tumors, but had different prognoses. Case 3, with more limited disease, had the highest rate of poorly differentiated areas but the lowest Ki-67 proliferation index. In conclusion, it is difficult to make claims about the clinical behavior and prognosis of thyroid carcinoma with an insular component based on the 3 cases reported in this study, but it can be speculated that there is a gap in the TNM system with regard to the staging of insular thyroid carcinoma. In this situation the assessment of microscopic and immunohistochemical features of the tumor may help to predict disease aggressiveness and patient risk. However, it is clear that there is a need for large-scale studies evaluating the prognostic importance of histopathological and immunohistochemical features in determining risk groups.

Tumor-to-tumor metastasis to a thyroid follicular adenoma as the initial presentation of a colonic adenocarcinoma

The incidence of thyroid involvement by metastatic disease from distant organs ranges from an average of 3.1% in surgical series to 5.3% in autopsy series. However, the metastasis of one tumor into another (traditionally referred to as 'tumor-to-tumor metastasis') is distinctly uncommon. Typically, they are identified as new manifestations or necropsy findings of a known, pre-existing donor tumor. Herein is described the case of a 59-year-old woman whose thyroid nodule (a follicular adenoma) was resected and found to contain foci of a well-differentiated adenocarcinoma with a morphologic and immunohistochemical profile consistent with origination from the lower gastrointestinal tract. Subsequent diagnostic work-up revealed a sigmoid colon tumor with metastases to the liver. This is, to the authors' knowledge, the first reported example of a colon adenocarcinoma whose initial clinical manifestation was a metastasis to a thyroid neoplasm and only the third reported example of a colonic adenocarcinoma metastatic to a thyroid tumor. In a review of previously reported examples of tumor-to-tumor metastases involving a thyroid neoplasm as the recipient, the following features were present in the majority: (i) multifocality of the metastatic tumor aggregates; (ii) a total lack of, or only minimal amounts of reaction (desmoplastic, inflammatory or myxoid) of the recipient tumor to the metastatic deposits; and (iii) retention of the histopathologic characteristics of the donor tumor in the metastatic deposits. In general, strikingly divergent morphologic features in an otherwise typical thyroid neoplasm should elicit a differential diagnosis that takes into consideration the possibility of metastasis.