Stromal Modulation and its Role in the Diagnosis of Papillary Patterned Thyroid Lesions

Abstract

The papillary patterned lesion of thyroid may be challenging with many diagnostic pitfalls. Tumor stroma plays an important part in the determination of the tumor phenotype. CD34 is thought to be involved in the modulation of cell adhesion and signal transduction as CD34(+) fibrocytes are potent antigen-presenting cells. Smooth muscle actin (SMA) positivity could be diagnostic for fibroblast activation during tumorigenesis. We aimed to examine the expression of CD34 and alphaSMA in the stroma of papillary thyroid hyperplasia, papillary thyroid carcinoma and papillary tumors of uncertain malignant potential in order to elucidate their possible differential distribution and roles. A total number of 54 cases with papillary thyroid lesions were studied by routine H&E staining, CD34 and ASMA immunostaining. ASMA was not expressed in benign papillary hyperplastic lesions while it was expressed in papillary carcinoma, indicating that tumors have modulated stroma. Although the stroma was not well developed in papillary lesions with equivocal features of uncertain potentiality, CD34 was notable in such cases with higher incidence in malignant cases. So ASMA as well as CD34 could predict neoplastic behavior, pointing to the importance of the stromal role. Differences between groups suggest that the presence of CD34 + stromal cells is an early event in carcinogensis and is associated with neoplasia, however ASMA+ cells are more likely to be associated with malignant behavior and metastatic potential adding additional tools to the light microscopic picture helping in diagnosis of problematic cases with H&E.

Age-related long-term response in rat thyroid tissue and plasma after internal low dose exposure to 131I

“…Several of these biomarker candidates have previously been associated with thyroid diseases. Positive ACTA2 staining is common in PTCs from adults (27–54 years) and related to higher tumour grade and metastatic potential 32 . High CA1 expression is related to hyperthyroidism, as already discussed.…”

Cancer Associated Fibroblasts and Senescent Thyroid Cells in the Invasive Front of Thyroid Carcinoma

“…Our results suggest the possibility that CAFs and TC cells may interact to promote tumor local invasion. Only a few previous studies have investigated CAFs in human thyroid tumors and were mainly focused on PTC, in which the occurrence of CAFs has been accordingly reported in tumor stroma [25][26][27][28][29] and associated with aggressive features as advanced stage [25] and lymph node metastases (LNMs) [26,28]. The presence of fibrotic collagenous stroma has been significantly associated with LNMs and peritumoral invasion in papillary thyroid microcarcinomas [30].…”

Nine Genes Mediate the Therapeutic Effects of Iodine-131 Radiotherapy in Thyroid Carcinoma Patients

“…CD34 is implicated in cell adhesion and signal transduction and is an indicator of neoplastic behaviour, and CD34 + stromal cells are related to the carcinogenesis of PTC [33]. Precursor CD34 + stromal cells or monocytes can develop into dendritic cells (DCs), and a higher number of DCs may contribute to the favourable prognosis of PTC [34].…”