Galectin-3 and CD44v6 positivity by RT-PCR method in fine needle aspirates of benign thyroid lesions

Quantitative Analysis of Galectin-3 Expression in Benign and Malignant Thyroid Nodules

In this study, galectin-3 was analyzed as a potential marker for preoperative detection of malignant thyroid lesions. Galectin-3 expression was analyzed by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) in preoperative thyroid fine-needle aspirates from 245 patients with thyroid nodules. Out of 245 samples, 238 were adequate for analysis by RT-PCR. Galectin-3 was positive in 34 (89.5%) of 38 papillary carcinomas, 3 (89.5%) of 4 follicular carcinomas, 17 (53.1%) of 32 follicular adenomas, 2 (33.3%) of 6 Hurthle cell adenoma, 11 (28.2%) of 39 Hashimoto thyroiditis, and 69 (57.9%) of 119 nodular goiter samples. Galectin-3 showed specificity of 49.5%, sensitivity of 88.1%, positive predictive value of 27.2%, and negative predictive value of 95.1% as a marker for detection of malignant thyroid nodules. Owing to the relatively low positive predictive value due to the relatively high false positive rate, the clinical value of galectin-3 analyzed by quantitative real-time RT-PCR as a marker for preoperative detection of malignant thyroid lesions is limited.

A study of Galactin-3 on fine needle aspiration as a diagnostic marker differentiating benign from malignant thyroid neoplasm

Background & Objective:

Thyroid nodules are very common in our setup and their diagnosis on fine needle aspiration is not easy and is a taxing affair. It is a challenge to differentiate between follicular adenoma and follicular carcinoma without histology. Our objective was to investigate the role of Galectin-3 in fine needle aspirates of thyroid nodules as a prospective diagnostic marker and consequently its ability to differentiate benign from malignant neoplasms.

Methods:

The research was conducted at the department of Pathology, King Edward Medical University, in association with other teaching institutions of Lahore from June 2012 to July 2014.. Sixty cases of solitary thyroid nodules were included in the study. Haematoxylin and eosin staining of the fixed smears and Galectin-3 immunohistochemical staining of the sections prepared from the cell block was performed.

Results:

There were 60 patients in our study with a mean age of 33.35 years. The Bethesda system for reporting thyroid cytopathology was used to classify the smears and only categories IV, V and VI were included. On histological examination of the resected nodules there were 38.3% (23/60) cases of follicular adenoma, 46.6% (28/60) were of papillary carcinoma and follicular carcinoma made up to 15% (9/60) of all cases. Galectin-3 was negative in 100% (23/23) cases of follicular adenomas. Out of 37 malignant cases 65% lesions showed positivity, while 35% showed negativity for this immunomarker. Considering the malignant lesions, 75% cases of papillary carcinomas showed a positive reaction while only 33% of follicular carcinomas were positive for the immunomarker. This showed that the positive expression was more common in papillary as compared to follicular carcinomas.

Conclusion:

Galectin-3immunomarker is considerably expressed in malignant tumors, but it is not expressed in benign follicular lesions.

Immunohistochemical levels of matrix metalloproteinase-2 and CD44 variant 6 protein in the diagnosis and lateral cervical lymph node metastasis of papillary thyroid carcinoma

OBJECTIVES

To investigate the ability of matrix metalloproteinase (MMP)-2 and CD44 variant 6 (CD44v6) protein levels to diagnose papillary thyroid cancer (PTC), compared with routine diagnostic methods using tissue sections; to explore the relationship between MMP-2 and CD44v6 protein levels and lymph node metastases (LNM) in PTC.

METHODS

Archival PTC specimens from patients with PTC, with or without lateral cervical LNM, were included in this retrospective immunohistochemical study. MMP-2 and CD44v6 protein levels were analysed immunohistochemically using routinely prepared tissue sections.

RESULTS

Specimens from 66 patients with PTC were reviewed retrospectively (35 patients with lateral cervical LNM; 31 patients without LNM). The percentages of samples with cells that demonstrated positive protein staining differed significantly between PTC specimens, benign thyroid nodules and adjacent normal follicular epithelium (MMP-2: 86.4%, 60.0%, and 25.7%, respectively; CD44v6: 80.3%, 37.1% and 22.9%, respectively). The level of CD44v6 protein staining was found to be significantly and positively correlated with the level of MMP-2 protein staining in PTC specimens.

CONCLUSIONS

Both MMP-2 and CD44v6 might be useful tumour markers for predicting risk of lateral cervical LNM in patients with PTC.

Methodology and technical requirements of the galectin-3 test for the preoperative characterization of thyroid nodules

In the last decade, the β-galactosyl binding protein galectin-3 has been the object of extensive molecular, structural, and functional studies aimed to clarify its biological role in cancer. Multicenter studies also contributed to discover the potential clinical value of galectin-3 expression analysis in distinguishing, preoperatively, benign from malignant thyroid nodules. As a consequence galectin-3 is receiving significant attention as tumor marker for thyroid cancer diagnosis, but some conflicting results mostly owing to methodological problems have been published. The possibility to apply preoperatively a reliable galectin-3 test method on fine needle aspiration biopsy (FNA)-derived thyroid cells represents an important achievement. When correctly applied, the method reduces consistently the gray area of thyroid FNA cytology, contributing to avoid unnecessary thyroid surgery. Although the efficacy and reliability of the galectin-3 test method have been extensively proved in several studies, its translation in the clinical setting requires well-standardized reagents and procedures. After a decade of experimental work on galectin-3-related basic and translational research projects, the major methodological problems that may potentially impair the diagnostic performance of galectin-3 immunotargeting are highlighted and discussed in detail. A standardized protocol for a reliable galectin-3 expression analysis is finally provided. The aim of this contribution is to improve the clinical management of patients with thyroid nodules, promoting the preoperative use of a reliable galectin-3 test method as ancillary technique to conventional thyroid FNA cytology. The final goal is to decrease unnecessary thyroid surgery and its related social costs.

Galectin-3 detection on large-needle aspiration biopsy improves preoperative selection of thyroid nodules: a prospective cohort study

BACKGROUND

New techniques of improving diagnostic reliability of thyroid nodules are needed.

AIM AND METHODS

This prospective cohort study includes patients with one (201) or multiple (22) palpable nodule(s). Preoperative fine-needle aspiration biopsy (FNAB), large-needle aspiration biopsy (LNAB), and galectin-3 detection on LNAB (GAL-3-LNAB) (total of 245 nodules) were compared when the FNAB finding was 'inadequate' or 'indeterminate'. The sizes of the needles used for FNAB and LNAB were compared with the size of thyroid follicles. Forty nodules were surgically excised according to current recommendation.

RESULTS

GAL-3-LNAB was inadequate in 4% of nodules, compared with 34% using FNAB and 11% using LNAB (P < 0.0001). GAL-3-LNAB showed no indeterminate findings, compared with 15% using FNAB and 13% using LNAB (P < 0.0001). Among the 40 excised nodules, GAL-3-LNAB showed the highest accuracy values. The sensitivity (P = 0.011) and specificity (P < 0.000; P = 0.001) ranges were 40%-100% and 20%-40% for FNAB, 40%-100% and 50%-53.7% for LNAB, and 100% and 76.7%-80% for GAL-3-LNAB, respectively. The largest needles used for LNAB, 20 or 18 gauge, with an internal diameter of 0.6 or 0.91 mm, recorded the lowest rate of inadequate or indeterminate FNAB findings.

CONCLUSIONS

GAL-3-LNAB reduced inadequate, abolished indeterminate findings, and provided specificity values higher than FNAB or LNAB in palpable thyroid nodules.

Cytoplasmic and serum galectin-3 in diagnosis of thyroid malignancies

In order to address whether galectin-3 in the sera and fine needle aspirates serve as a diagnostic marker distinguishing between benign and malignant thyroid nodules, we developed an enzyme-linked immunosorbent assay. We quantified galectin-3 in fine needle aspirates from a series of 118 patients with thyroid nodules and serum galectin-3 from another series of 46 patients, which were compared with final histology after thyroidectomy. Relative galectin-3 value (ng/mg), defined as galectin-3 concentration (ng/ml) divided by total protein concentration (mg/ml) in fine needle aspirates, was significantly higher in papillary carcinoma than in the other thyroid entities. There was no significant difference in serum galectin-3 level among patients with thyroid nodules and healthy individuals. Accordingly, relative galectin-3 value allows a definitive diagnosis of papillary carcinoma independent of cellular morphology, whereas serum galectin-3 does not serve as a marker for papillary carcinoma.

Thyroid fine-needle aspiration samples inadequate for reverse transcriptase-polymerase chain reaction analysis

BACKGROUND

Analysis of different tumor markers by reverse transcriptase-polymerase chain reaction (RT-PCR) in fine-needle aspiration samples of thyroid nodules has been studied with the objective of improving the accuracy of the preoperative diagnosis of thyroid lesions. The aim of the current study was to investigate thyroid fine-needle aspiration samples inadequate for RT-PCR analysis and to determine whether there is a correlation between their proportion and the method of sampling used or the greatest dimension of the nodules.

METHODS

A total of 350 fine-needle aspiration samples from patients with thyroid nodules were analyzed. After the aspirate was smeared for conventional cytology, the leftover material in the needle was used for RT-PCR analysis in 1 group of 175 patients. In another group of 175 patients, a separate puncture was performed to obtain material for RT-PCR analysis only. Samples were considered adequate for RT-PCR analysis if the expression of both glyceraldehyde-3-phosphate dehydrogenase and thyroglobulin was found by RT-PCR.

RESULTS

In total, 61 (17.4%) samples inadequate for RT-PCR were detected. All 12 samples that were inadequate for cytologic diagnosis were also found to be inadequate for RT-PCR analysis. The proportion of inadequate samples for RT-PCR was found to be significantly higher in samples taken from leftover material in the needle (21.7%) then in samples from a separate puncture (13.1%) (P = .049). No statistically significant correlation between the adequacy of samples for RT-PCR and the largest dimension of the nodule was found.

CONCLUSIONS

The proportion of samples inadequate for RT-PCR was found to be higher in samples taken from leftover material in the needle than in samples obtained from a separate puncture.

Update on the molecular diagnosis of endocrine tumors: toward -omics-based personalized healthcare?

Genetic advances in endocrine neoplasia provided the paradigm for the practice of clinical cancer genetics: germline RET mutations in multiple endocrine neoplasia type 2. In the last 14 yr, both genetics and -omics advances have occurred, almost exponentially in the last 5 yr. The time has come to reevaluate recent advances in genomic medicine's promise to revolutionize personalized healthcare in the context of endocrine neoplasias. This update focuses on two examples of endocrine neoplasias, those of the thyroid and of the adrenal, and discusses recent advances in germline and somatic genetics and genomics, as they relate to clinical application.