Non-tumor-associated psammoma bodies in the thyroid

Thyroid Parenchyma Microcalcifications on Ultrasound for Predicting Lymph Node Metastasis in Papillary Thyroid Carcinoma: A Prospective Multicenter Study in China

Objective: Cervical lymph node metastasis (LNM) was found to be clinically significant prognostic factors of patients with papillary thyroid carcinomas (PTC). Ultrasound (US) characteristics of thyroid nodules and thyroid parenchyma may be used to predict LNM. To investigate the value of nodular US features as well as thyroid parenchymal microcalcifications on US in predicting LNM in patients with PTC. Methods: This prospective study was approved by the Institutional Review Board. From January 2018 to June 2019, 971 consecutive patients with solitary PTC who underwent preoperative neck US evaluation were included from six hospitals in China. The US features of thyroid nodules as well as thyroid parenchyma microcalcifications were carefully evaluated based on the static images and dynamic clips. Univariate and multivariate analyses were performed to determine independent predictors of LNM. Results: Of the 971 patients, 760 were female, 211 were male. According to the pathological examination, 241(24.82%) patients were found with cervical LNM (LNM positive group), while 730 (75.18%) patients were not (LNM negative group). Multiple logistic regression analysis showed that young age (<55 years old) (OR = 1.522, P = 0.047), large size (>10 mm) (OR = 1.814, P < 0.001), intratumoral microcalcifications (OR = 1.782, P = 0.002) and thyroid parenchyma microcalcifications (OR = 1.635, P = 0.046) were independent risk factors for LNM of PTC. Conclusions: Young age, large nodule size, intratumoral microcalcifications, as well as thyroid parenchyma microcalcifications on US are independent predictors of cervical LNM for patients with PTC.

Localization and characterization of thyroid microcalcifications: A histopathological study

Thyroid calcification is frequent in thyroid nodules. The aim of our study was to evaluate the prevalence of calcifications in thyroid tissue samples of patients with various thyroid diseases, and to identify their composition according to their localization. Among 50 thyroid samples included, 56% were malignant (papillary carcinoma) and 44% were benign (adenoma, multinodular goiter, Graves' disease, sarcoidosis). Calcifications were found in 95% of samples using polarised light microscopy, whereas only 12% were described in initial pathological reports. Three types were individualised and analyzed by infrared spectrometry (μFTIR): colloid calcifications composed of calcium oxalate, capsular calcifications and psammoma bodies, both composed of calcium phosphate. Of notice, psammoma bodies characterized by FE-SEM were composed of concentric structure suggesting a slow process for crystal deposition. Calcium phosphates were found only in malignant samples whereas calcium oxalate was not associated with a define pathology. Proliferation assessed by KI67 staining was high (33% of positive follicles), and RUNX2, OPN, and CD44 positive staining were detected in thyrocytes with a broad variation between samples. However, thyrocyte proliferation and differentiation markers were not associated with the number of crystals. TRPV5 and CaSR expression was also detected in thyrocytes. mRNA transcripts expression was confirmed in a subgroup of 10 patients, altogether with other calcium transporters such as PMCA1 or Cav1.3. Interestingly, TRPV5 mRNA expression was significantly associated with number of colloid calcifications (rho = -0.72; p = 0.02). The high prevalence of calcium oxalate crystals within colloid gel raises intriguing issues upon follicle physiology for calcium and oxalate transport.

Papillary Thyroid Cancer: Genetic Alterations and Molecular Biomarker Investigations

Papillary thyroid cancer (PTC) is the most prevalent form of malignancy among all cancers of the thyroid. It is also one of the few cancers with a rapidly increasing incidence. PTC is usually contained within the thyroid gland and generally biologically indolent. Prognosis of the cancer is excellent, with less than 2% mortality at 5 years. However, more than 25% of patients with PTC developed a recurrence during a long term follow-up. The present article provides an updated condensed overview of PTC, which focuses mainly on the molecular alterations involved and recent biomarker investigations.

Leiomyoma of the thyroid gland with psammoma bodies

We report a rare case of leiomyoma of the thyroid gland associated with psammoma bodies. The patient was a 9-year-old black African boy. Prior to this, only five cases of primary thyroid leiomyoma have been reported. Histologically, thyroid leiomyoma was characterised by bundles of spindle smooth muscle cells with blunt-ended nuclei. Psammoma bodies were widely distributed within the tumour. Immunohistochemistry showed positive immunoreactivity for smooth muscle actin, vimentin and desmin, but was negative for a cytokeratin cocktail. Further reports of similar cases is required to ascertain the clinical significance of this lesion.

Simultaneous diffuse sclerosis variant of papillary thyroid carcinoma and diffuse toxic hyperplasia (Graves' disease)

Diffuse sclerosis variant of papillary thyroid carcinoma (DSVPTC) is an unusual malignant neoplasm that typically permeates the entire gland resulting in diffuse thyroid enlargement. In the absence of a dominant nodule, DSVPTC can be histologically deceiving because of exuberant inflammation and the scattered distribution of the microscopic tumor islands. The difficulty in diagnosing this tumor is compounded by its rarity and unusual clinical and histologic features. Herein, we describe a unique case of DSVPTC that was clinically masked by a co-existing second diffuse thyroid process--Graves' disease (GD). A subtotal thyroidectomy was performed in a 27-yr-old Caucasian female who presented with symmetrical diffuse thyromegaly with neck compressive symptoms, thyrotoxicosis, and biochemical signs of GD. Histologic examination of the thyroid gland unexpectedly revealed extensive involvement by DSVPTC in addition to the diffuse hyperplastic non-malignant thyroid follicles. This report illustrates the histologic features as well as the diagnostic challenge encountered in a rare simultaneous occurrence of DSVPTC and GD.<P>