Fetal cell microchimerism in papillary thyroid cancer: A role in the outcome of the disease.

Fetal cell microchimerism (FCM) is defined as the persistence of fetal cells in maternal organs and circulation without any apparent rejection and it was hypothesized to protect toward the onset of some neoplastic diseases. To verify the role of FCM in papillary thyroid cancer (PTC), we enrolled 87 parous women with PTC and at least one male pregnancy preceding the diagnosis (PTC-P), 66 healthy women with 1 or more male children (HC-P) and 57 nonparous women with PTC (PTC-NP). The presence of circulating male DNA was assessed by the amplification of the Y chromosome-specific gene SRY, with a sensitivity of 1 male cell/1 million female cells. A significantly higher frequency of FCM was found in HC-P than PTC-P women (63.6% vs. 39.1%, p = 0.004). Among PTC-P patients, those positive for the presence of FCM (FMC+ve) had a lower prevalence of extrathyroidal extension (p = 0.027) and lymph node metastases (p = 0.044) than those without FCM (FMC-ve). Moreover, FMC+ve patients were more frequently in remission than FMC-ve cases (94.1 vs. 67.9%, p = 0.009). Interestingly, we showed for the first time that the positive effect on tumor presentation and outcome is specifically related to FCM and it is not an effect of pregnancy. In conclusion, circulating FCM is significantly more frequent in healthy parous women than in women with PTC. Moreover, the presence of circulating fetal male cells is associated with a significantly lower extrathyroidal extension and a good prognosis, suggesting a protective role of this phenomenon toward both the onset and the progression of thyroid cancer.

Prevalence and clinical features of armadillo repeat-containing 5 mutations carriers in a single center cohort of patients with bilateral adrenal incidentalomas.

OBJECTIVE: We aimed to evaluate the prevalence of armadillo repeat-containing 5 (ARMC5) genetic defects in our cohort of bilateral adrenal incidentaloma (BAI) patients and to evaluate the possible existence of genotype-phenotype correlations. DESIGN: Cross-sectional study. SETTING: Tertiary care center. PARTICIPANTS: 72 BAI patients. MAIN OUTCOME MEASURE(S): The following data have been collected: morning adrenocorticotropic hormone (ACTH) concentrations; cortisol levels after 1 mg overnight dexamethasone suppression test (F-1mgDST); urinary free cortisol (UFC) levels; diameter of the adrenal masses; and the association with overweight/obesity, arterial hypertension, diabetes mellitus, dyslipidemia, cardiovascular events, unrelated neoplasia, osteoporosis, thyroid nodular disease, and primary hyperparathyroidism. A search for ARMC5 germline and somatic pathogenic variants was performed in all patients and in the adrenal tissue of patients operated on, respectively. RESULTS: The prevalence of germline ARMC5 pathogenic variants among patients with mild autonomous cortisol secretion (MACS+, defined as F-1mgDST > 1.8 µg/dL) was 18.8%. No germline pathogenic variants were detected in patients without MACS. Moreover, somatic ARMC5 pathogenic variants were also found in the adrenal tissue of six patients without germline ARMC5 variants. The F-1mgDST levels >5 µg/dL predicted with a poor sensitivity but a 90.5% specificity in identifying the presence of ARMC5 germline pathogenic variants. We did not find any clinical parameter predictive of the ARMC5 mutation presence. CONCLUSIONS: In MACS+ BAI patients, germline ARMC5 gene pathogenic variants are frequent. Further studies are needed to elucidate the pathophysiological role of somatic ARMC5 pathogenic variants on adrenal tumor development in otherwise wild-type (WT) patients.

Case Report: A Novel ARMC5 Germline Mutation in a Patient with Primary Bilateral Macronodular Adrenal Hyperplasia and Hypogammaglobulinemia.

Primary bilateral macronodular adrenal hyperplasia (PBMAH) represents an uncommon cause of endogenous hypercortisolism. Since the first description in 2003 in a French cohort, many papers have been published describing families as well as isolated individuals affected with this condition, who were found to harbor a genetic variants in the armadillo-repeat containing 5 (ARMC5) gene, a tumor-suppressor gene with a still unknown role in the disease pathogenesis. Studies in rat models suggested a possible link between ARMC5 damaging variants and the impairment of the cell-mediated immune response, leading to a higher susceptibility to bacterial and viral infections. To our knowledge, we describe the first case of a patient affected by PBMAH with hypogammaglobulinemia and monthly relapsing human herpes simplex viral infections. After the detection of subclinical Cushing's syndrome, a unilateral laparoscopic adrenalectomy was performed. Subsequent genetic analysis of ARMC5 performed on genomic DNA extracted both from the adrenal tissue and lymphocytes revealed a novel somatic frameshift variant in exon 1 (c.231_265del:p.A77Afs*13) and a novel germline variant in exon 6 (c.2436del: p. C813Vfs*104). After adrenalectomy, we observed a significant improvement of clinical features concerning both hypercortisolism and relapsing viral infections, thus suggesting a possible adjuvant role of hypercortisolism on a genetic-based derangement of the immune system.

Improved Molecular Diagnosis of McCune-Albright Syndrome and Bone Fibrous Dysplasia by Digital PCR.

McCune-Albright syndrome (MAS) is a rare congenital disorder characterized by the association of endocrine and nonendocrine anomalies caused by somatic activating variants of GNAS. The mosaic state of variants makes the clinical presentation extremely heterogeneous depending on involved tissues. Biological samples bearing a low level of mosaicism frequently lead to false-negative results with an underestimation of causative molecular alterations, and the analysis of biopsies is often needed to obtain a molecular diagnosis. To date, no reliable analytical method for the noninvasive testing of blood is available. This study was aimed at validating a novel and highly sensitive technique, the digital PCR (dPCR), to increase the detection rate of GNAS alterations in patients with a clinical suspicion of MAS and, in particular, in blood. We screened different tissues (blood, bone, cutis, ovary, and ovarian cyst) collected from 54 MAS patients by different technical approaches. Considering blood, Sanger was unable to detect mutations, the allele-specific PCR and the co-amplification at lower denaturation temperature had a 9.1% and 18.1% detection rate, respectively, whereas the dPCR reached a 37.8% detection rate. In conclusion, the dPCR resulted in a cost-effective, reliable, and rapid method allowing the selective amplification of low-frequency variants and able to improve GNAS mutant allele detection, especially in the blood.

Retinal Photoreceptor Functions Are Compromised in Patients With Resistance to Thyroid Hormone Syndrome (RTHß).

Context: In animal models, disruption of thyroid hormone (TH) receptor-ß (TRß) reduces the long/medium wavelength (L/M) and increases the short-wavelength (S) cones. Retinal photoreceptor (RP) functions are unknown in patients with resistance to TH syndrome (RTHß) with dominant-negative TRß mutations. Objective: To investigate RP functions in RTHß. Design, Setting, and Participants: Case-control study involving 27 RTHß patients and 31 age/sex-matched controls, conducted in two tertiary referral centers in Italy. Main Outcome Measures: Color vision sensitivity assessed by Farnsworth; central macular thickness (CMT) of the outer retinal layer measured by spectral-domain optical coherence tomography; and retinal function tested by full-field electroretinogram (ERG) and S-cone ERG. Results: Color sensitivity was worse in RTHß patients than controls (P = 0.002). CMT was overlapping between the study groups but directly correlated with sex hormone-binding globuline levels in RTHß. We found a significant reduction in amplitude of the cone (P = 0.024) and of the rod response (P = 0.006) in the ERG of RTHß patients compared with controls. The response of the L/M cones measured by a specialized ERG test was lower in RTHß than controls (P = 0.027), whereas no differences were found in the S-cone response. No correlations were found between TH levels, total error score, or electrophysiological results. Furthermore, no differences were found between patients with maternal or de novo/paternal inheritance. Conclusions: We report, to our knowledge, the first in vivo evidence of functional defects of RP in RTHß. These changes occur independently of endogenous TH levels or the prenatal exposure to high or normal maternal TH.

Fetal cell microchimerism: a protective role in autoimmune thyroid diseases.

OBJECTIVE: The physiological persistence of fetal cells in the circulation and tissue of a previously pregnant woman is called fetal cell microchimerism (FCM). It has been hypothesized to play a role in systemic autoimmune disease; however, only limited data are available regarding its role in autoimmune thyroid disease (AITD). DESIGN: Circulating FCM was analyzed in a large series of previously pregnant women with Graves' disease (GD), Hashimoto's thyroiditis (HT), or no disease (healthy controls (HCs)). To exclude the possible bias related to placental factors, the polymorphic pattern of human leukocyte antigen-G (HLA-G) gene, which is known to be involved in the tolerance of fetal cells by the maternal immune system, was investigated. METHODS: FCM was evaluated by PCR in the peripheral blood, and the Y chromosome was identified by fluorescence in situ hybridization in some GD tissues. HLA-G polymorphism typing was assessed by real-time PCR. RESULTS: FCM was significantly more frequent in HC (63.6%) than in GD (33.3%) or HT (27.8%) women (P=0.0004 and P=0.001 respectively). A quantitative analysis confirmed that circulating male DNA was more abundant in HC than it was in GD or HT. Microchimeric cells were documented in vessels and in thyroid follicles. In neither GD/HT patients nor HC women was the HLA-G typing different between FCM-positive and FCM-negative cases. CONCLUSION: The higher prevalence of FCM in HC as compared to GD and HT patients suggests that it plays a possible protective role in autoimmune thyroid disorders. Placental factors have been excluded as determinants of the differences found. The vascular and tissue localization of microchimeric cells further highlights the ability of those cells to migrate to damaged tissues.

The limited role of midnight salivary cortisol levels in the diagnosis of subclinical hypercortisolism in patients with adrenal incidentaloma.

OBJECTIVE: The criteria for defining subclinical hypercortisolism (SH) are debated and a real gold standard test or combination of tests is lacking. Recently, late-night salivary cortisol (MSC) has been described as a sensitive and easy-to-perform marker for diagnosing overt hypercortisolism. No data are available on the role of MSC in the diagnosis of SH. The aim of this study was to evaluate the sensitivity and specificity of MSC levels in the diagnosis of SH in patients with adrenal incidentalomas (AI). METHODS: In 103 (females/males, 69/34) patients with AI, MSC levels were studied. One milligram overnight dexamethasone suppression test (DST), urinary-free cortisol (UFC), and ACTH plasma levels were also evaluated. Patients were defined as affected by SH if they showed two of the following criteria: DST>83 nmol/l, ACTH <2.2 pmol/l, and UFC >193 nmol/24 h. RESULTS: No difference in MSC levels in patients with SH (3.1+/-3.1 nmol/l) compared with patients without SH (2.2+/-2.8 nmol/l) was observed. In patients with SH, MSC levels were significantly correlated with DST (r=0.4, P<0.05). Using the cut-off of 5.1 nmol/l, the sensitivity and specificity of MSC levels for diagnosis of SH is 22.7 and 87.7% respectively. CONCLUSION: In patients with AI, normal levels of MSC do not exclude SH, whereas high levels may suggest the presence of SH identified by conventional tests. Thus, MSC is not suitable as a screening test, although it may be used in conjunction with other tests as the confirming test in selected patients.