Hereditary medullary thyroid carcinoma: the management dilemma

"Immunocytochemistry in Cytology: Myth or Reality": Unraveling the Myth - Immunocytochemistry Applications in Thyroid Lesions

BACKGROUND

Fine-needle aspiration cytology serves as an important preoperative diagnostic tool for thyroid nodules. Despite its excellent diagnostic accuracy, diagnoses based solely on morphological observation can be challenging. Therefore, various ancillary diagnostic techniques have been applied, including immunocytochemistry (ICC). This review discusses the application and evaluation of ICC in thyroid fine needle aspiration.

SUMMARY

Currently, three immunostaining preparation methods are available for cytological materials: liquid-based cytology, cell block, and cell transfer. ICC proves valuable in scenarios such as tumour diagnosis, assessment of differentiation and grading of carcinomas, estimation of primary organs in metastatic carcinomas, and detection of gene abnormalities. However, ICC, while useful, is not as accurate as immunohistochemistry and is more difficult to evaluate.

KEY MESSAGES

If the pitfalls and limitations are understood and effectively navigated, ICC could play a significant role in decreasing the non-diagnostic rate, thus leading to more accurate and valuable diagnoses and reductions in the re-aspiration rate.

BACKGROUND

Fine-needle aspiration cytology serves as an important preoperative diagnostic tool for thyroid nodules. Despite its excellent diagnostic accuracy, diagnoses based solely on morphological observation can be challenging. Therefore, various ancillary diagnostic techniques have been applied, including immunocytochemistry (ICC). This review discusses the application and evaluation of ICC in thyroid fine needle aspiration.

SUMMARY

Currently, three immunostaining preparation methods are available for cytological materials: liquid-based cytology, cell block, and cell transfer. ICC proves valuable in scenarios such as tumour diagnosis, assessment of differentiation and grading of carcinomas, estimation of primary organs in metastatic carcinomas, and detection of gene abnormalities. However, ICC, while useful, is not as accurate as immunohistochemistry and is more difficult to evaluate.

KEY MESSAGES

If the pitfalls and limitations are understood and effectively navigated, ICC could play a significant role in decreasing the non-diagnostic rate, thus leading to more accurate and valuable diagnoses and reductions in the re-aspiration rate.

Genes of detoxification are important modulators of hereditary medullary thyroid carcinoma risk

CONTEXT

Different inherited profiles of genes involved in cellular mechanisms of activation and detoxification of carcinogenic products can provide specific protection or determine the risk for cancer. Low-penetrance polymorphic genes related to the biotransformation of environmental toxins have been associated with susceptibility to and the phenotype of, human tumours.

OBJECTIVE

To investigate the role of germline inheritance of polymorphisms in CYP1A2*F, CYP1A1 m1, GSTP1, NAT2 and TP53 genes in hereditary medullary thyroid carcinoma (HMTC) patients.

DESIGN

This study was developed in University of Campinas (Unicamp).

PATIENTS

We studied 132 patients with HMTC, 88 first-degree relatives of HMTC patients and 575 control individuals.

MEASUREMENTS

All patients with MTC and their relatives were sequenced for the RET gene and five genes were genotyped using TaqMan(®) system.

RESULTS

We observed that the inheritance of CYP1A2*F (OR = 2·10; 95% CI = 1·11-3·97; P = 0·022), GSTP1 (OR = 4·41; 95% CI = 2·47-7·88; P < 0·001) and NAT2 (OR = 2·54; 95% CI = 1·16-5·58; P = 0·020) variants increased the risk for HMTC. In addition, multiple regression analysis showed that the inheritance of GSTP1 polymorphisms was associated with the diagnosis in older patients (B = 8·0229; 95% IC = ± 5·5735; P = 0·0054). Concerning the group of HTMC relatives, CYP1A2*F (OR = 2:40; 95% CI = 1·19-4·86; P = 0·015), CYP1A1 m1 (OR = 2·79; 95% CI = 1:04-7·51; P = 0·042), GSTP1 (OR = 2·86; 95% IC = 1·53-5·32; P < 0·001) and NAT2 (OR = 2·25; 95% IC = 1·20-4·22; P = 0·012) were associated with HMTC risk.

CONCLUSIONS

We have demonstrated that the inheritance of specific genes determining the individual response to environmental toxins may contribute to the risk and phenotypic variability that exists in patients with HMTC. Moreover, we identified a group at risk in relatives of HMTC patients.

A new genome scan for primary nonsyndromic vesicoureteric reflux emphasizes high genetic heterogeneity and shows linkage and association with various genes already implicated in urinary tract development

Primary vesicoureteric reflux (VUR), the retrograde flow of urine from the bladder toward the kidneys, results from a developmental anomaly of the vesicoureteric valve mechanism, and is often associated with other urinary tract anomalies. It is the most common urological problem in children, with an estimated prevalence of 1–2%, and is a major cause of hypertension in childhood and of renal failure in childhood or adult life. We present the results of a genetic linkage and association scan using 900,000 markers. Our linkage results show a large number of suggestive linkage peaks, with different results in two groups of families, suggesting that VUR is even more genetically heterogeneous than previously imagined. The only marker achieving P < 0.02 for linkage in both groups of families is 270 kb from EMX2. In three sibships, we found recessive linkage to KHDRBS3, previously reported in a Somali family. In another family we discovered sex-reversal associated with VUR, implicating PRKX, for which there was weak support for dominant linkage in the overall data set. Several other candidate genes are suggested by our linkage or association results, and four of our linkage peaks are within copy-number variants recently found to be associated with renal hypodysplasia. Undoubtedly there are many genes related to VUR. Our study gives support to some loci suggested by earlier studies as well as suggesting new ones, and provides numerous indications for further investigations.