ACR TI-RADS Score combined with cytopathology classification improves the risk stratification of indeterminate thyroid nodules

BACKGROUND

The aim of this retrospective study was the elaboration of a new diagnostic model that integrate cytological reports (2017 Bethesda System for Reporting Thyroid Cytopathology) with ultrasonographic features (based on ACR TI-RADS score) to achieve a more accurate definition of indeterminate thyroid nodule malignancy risk.

METHODS

Ninety patients submitted to thyroidectomy were divided in three classes: low malignancy risk (AUS/FLUS with TI-RADS 2/TI-RADS 3 and FN/SFN with TI-RADS 2), intermediate malignancy risk (AUS/FLUS with TI-RADS 4/TI-RADS 5 and FN/SFN with TI-RADS 3/TI-RADS 4), and high malignancy risk (FN/SFN with TI-RADS 5).

RESULTS

The surgical approach should be recommended in high-risk patients (81.82% of malignancies), carefully evaluated in intermediate risk (25.42%), whereas a conservative approach can be adopted in low-risk patients (0.00%).

CONCLUSIONS

The integration of these two multiparametric systems in a Cyto-US score has proven to be a feasible and reliable aid to achieve a more accurate definition of malignancy risk.

Prevalence of parietal cell antibodies in a large cohort of patients with autoimmune thyroiditis

BACKGROUND

Autoimmune thyroiditis (AIT) may be associated with other organ-specific autoimmune disorders, including autoimmune gastritis, but the prevalence of this association is not entirely quantified. The aim of this study was to investigate the prevalence of parietal cell antibodies (PCA) in a large cohort of consecutive patients with AIT.

METHODS

We retrospectively studied 2016 consecutive women and 258 men with AIT seen at our referral center in the period from 2004 to 2008. All patients were screened for the presence of PCA in the serum.

RESULTS

The prevalence of serum PCA in female patients was 29.7% and progressively increased from 13% in the first-second decade of life to peak at 42% in the ninth decade. During follow up, 21.1% of the PCA-positive patients converted to PCA-negative status. Mean (±standard deviation) basal PCA levels in this group were significantly lower (32 ± 28 U/mL) compared with those remaining PCA positive (129 ± 200 U/mL). A similar prevalence (29.8%) with a similar age-dependency was found in male patients.

CONCLUSIONS

In conclusion, our study demonstrates a high, age-dependent prevalence of PCA in an unselected large population of patients with AIT.

Acute exogenous TSH administration stimulates leptin secretion in vivo

TSH-receptor (TSHR) has been found in a variety of cell types, including preadipocytes and adipocytes. In vitro, TSH-mediated preadipocyte and adipocyte responses include proliferation, differentiation, survival, and lipolysis. Objective To measure the response of serum leptin to exogenous administration of recombinant human TSH (rhTSH) in vivo. Patients One hundred patients with differentiated thyroid cancer already treated by total thyroidectomy and (131)I remnant ablation were enrolled. Mean (+/-s.e.m.) body mass index (BMI) was 26.9+/-0.6 kg/m(2). Methods Patients received a standard dose of rhTSH for measurement of thyroglobulin in the follow-up of their disease. Blood samples were taken for the assay of TSH and leptin before the first administration of rhTSH (time 0), and 24 h (time 1), 48 h (time 2), 72 h (time 3), and 96 h (time 4) after the first administration of rhTSH. Results Significant mean serum leptin increments, with respect to basal value, were 16, 13, 18, and 11% at times 1, 2, 3, and 4 respectively. Significant positive correlations of leptin-area under the curve with respect to basal leptin levels (r=0.43; P<0.0001) and BMI (r=0.32; P<0.005) were observed. Conclusions Acute rhTSH administration in hypothyroid subjects under l-thyroxine therapy produces a rise in serum leptin. This increase is proportional to the adipose mass suggesting that a functioning TSHR is expressed on the surface of adipocytes. The role that TSHR activation in adipocytes might play in physiological and pathological conditions remains a matter of investigation.

Serum ghrelin levels in growth hormone-sufficient and growth hormone-deficient patients during growth hormone-releasing hormone plus arginine test

BACKGROUND AND AIMS

Ghrelin is an orexigenic hormone produced in the stomach and in other organs, exerting a wide range of metabolic functions, including stimulation of GH secretion. Ghrelin secretion is decreased by iv or oral glucose load as well as during euglycemic-hyperinsulinemic clamp and hypoglycemia. We evaluated the circulating ghrelin levels in GH-deficient (GHD) and in GH-sufficient (GHS) patients during GHRH plus arginine test.

MATERIALS AND METHODS

The study group comprised 35 patients, including 20 with pituitary tumors, 12 with empty sella, 2 with short stature, and 1 with post-traumatic isolated GH deficiency. According to the results of GHRH plus arginine test, 14 patients were defined as GHD and 21 as GHS. Patients with central hypothyroidism, hypocorticism, and hypogonadism had been on replacement therapy for at least 3 months at the moment of the study. Blood samples were collected every 20 min up to 60 min after GHRH and arginine administration.

RESULTS

By definition, GH response to GHRH plus arginine was higher in GHS than GHD group (p<0.0001). Basal serum ghrelin levels were not different in the two groups and did not correlate with body mass index, GH, IGFI and insulin concentrations. After GHRH plus arginine, serum ghrelin decreased significantly in both groups, with percent decreases ranging 13.3-66.6% in GHD patients (p=0.001) and 7.2-42.2% in GHS patients (p=0.004), with no significant difference in the two groups (p=0.12).

CONCLUSION

Our results show that ghrelin secretion is not modulated by acute GH increase observed in GHS subjects during GHRH plus arginine infusion. The similar decrease of serum ghrelin after GHRH plus arginine stimulation in both GHS and GHD subjects demonstrated that there is no negative feedback of GH on ghrelin secretion.

L-thyroxine requirement in patients with autoimmune hypothyroidism and parietal cell antibodies

BACKGROUND

Hypothyroid patients on l-T(4) therapy may require replacement doses exceeding the theoretical needs to normalize serum TSH due to low patient compliance, drugs interference, and malabsorption.

OBJECTIVE

We examined whether autoimmune gastritis might cause increased l-T(4) requirement in patients with autoimmune thyroiditis receiving l-T(4) replacement.

PATIENTS

We studied 391 patients with clinical or subclinical hypothyroidism from autoimmune thyroiditis who had achieved normal serum TSH concentration (0.3-3.0 microU/ml) under l-T(4) for at least 6 months. Patients were screened for serum parietal cell antibodies (PCA) as a marker of autoimmune gastritis, and the PCA status was correlated with the l-T(4) dose. We also studied a group of 60 patients receiving l-T(4) replacement after total thyroidectomy.

RESULTS

PCA-positive (155 of 391) and PCA-negative (236 of 391) patients did not differ for pretherapy serum TSH levels and thyroid volume. The l-T(4) requirement was significantly (P = 0.002) higher in PCA-positive (1.24 +/- 0.40 microg/kg x d) than in PCA-negative patients (1.06 +/- 0.36 microg/kg x d), and a significant positive correlation was found between l-T(4) requirement and serum PCA levels. Among PCA-positive patients, l-T(4) requirement was even higher in those with proven gastritis (1.52 +/- 0.40 microg/kg x d) compared with those without gastric damage (1.15 +/- 0.33 microg/kg x d) (P < 0.0001). The increased l-T(4) requirement was confirmed also in PCA-positive thyroidectomized patients (1.81 +/- 0.27 microg/kg x d) compared with PCA-negative thyroidectomized patients (1.52 +/- 0.24 microg/kg x d). Independent variables affecting l-T(4) requirement were PCA and serum TSH at diagnosis.

CONCLUSIONS

Autoimmune gastritis is an additional factor affecting l-T(4) requirement in patients with autoimmune thyroiditis. Serum PCA measurement should be considered in patients with an unexplained high requirement of l-T(4).

Serum ghrelin as a marker of atrophic body gastritis in patients with parietal cell antibodies

AIM

Autoimmune gastritis is frequently associated with autoimmune thyroiditis and other organ-specific autoimmune diseases, and may lead to atrophic body gastritis (ABG). We studied the diagnostic use of the measurement of serum ghrelin compared with other markers of gastric damage in predicting the presence of ABG in patients with autoimmune gastritis.

METHODS

We studied 233 patients with autoimmune gastritis and 211 control subjects. All patients and control subjects were screened for circulating parietal cell antibodies (PCAs) and were tested for serum ghrelin, gastrin, pepsinogen I and II, and anti-Helicobacter pylori antibody levels. A total of 52 patients and 28 control subjects underwent a gastric endoscopy.

RESULTS

In PCA/positive patients, mean (+/-sd) serum ghrelin levels were significantly lower (238 +/- 107 pmol/liter), and mean (+/-sd) serum gastrin levels were significantly higher (81.2 +/- 128.3 ng/ml), with respect to PCA/negative patients (282 +/- 104 pmol/liter and 20.7 +/- 13.3 ng/ml, respectively; P < 0.0001). Serum ghrelin and gastrin levels were inversely correlated (P = 0.004). A total of 40 patients had ABG documented by the gastric biopsy (90% in PCA/positive patients and 10% in PCA/negative patients). The receiver operating characteristic curve analysis revealed that a cutoff value for serum ghrelin of 188 pmol/liter was associated with the highest sensitivity and specificity (97.3 and 100%, respectively) in detecting gastric atrophy and was superior to gastrin (P = 0.012), PCA (P = 0.002), and the pepsinogen I/II ratio (P = 0.016) measurements.

CONCLUSIONS

Our study demonstrates that ghrelin secretion is negatively affected by autoimmune gastritis, and its serum level represents the most sensitive and specific noninvasive marker for selecting patients at high risk for ABG.

Cyclic Cushing's disease with paradoxical response to dexamethasone

Cyclic Cushing's disease is an unusual disorder characterised by ACTH-dependent periodical increase of serum cortisol levels, clinically accompanied by peripheral edema, abnormalities of cardiac rhythm and hypokalemia. The condition may be unrecognised for years, since the typical features of Cushing's disease are usually absent due to the intermittent and brief duration of cortisol hypersecretion. We describe the case of a 42-yr-old man with Cyclic Cushing's disease due to an ACTH-producing pituitary macroadenoma, who presented two episodes of hypercortisolism in a 3-yr-period, clinically characterised by peripheral edema, hypokalemia and arrhythmia. The diagnosis was suspected because of a paradoxical increase of plasma ACTH and cortisol after dexamethasone administration during an asymptomatic period and was confirmed by pituitary imaging and by final histology after transphenoidal resection of the pituitary adenoma. After surgery, the patient resumed a normal pituitary-adrenal function with restoration of the normal ACTH and cortisol suppression after dexamethasone. Cyclic Cushing's disease should be considered in the differential diagnosis of several conditions characterised by recurrent episodes of idiopathic edema, hypokalemia or unexplained cardiac arrhythmia. In such patients, the pituitary-adrenal axis should be tested possibly during the acute phase of their disease or using the dexamethasone suppression test during asymptomatic intervals.

Presurgical serum thyroglobulin has no prognostic value in papillary thyroid cancer

We investigated whether serum thyroglobulin determination before surgery for differentiated thyroid carcinoma may have any prognostic value with regard to tumour extension and disease outcome in a retrospective series of 71 patients with papillary thyroid cancer. Presurgical serum thyroglobulin levels were correlated with the size of the primary tumoral nodule (p = 0.006) and of the whole thyroid (p = 0.02). The same correlation was found in a control group of patients with benign thyroid nodules, confirming that presurgical serum thyroglobulin cannot be used for the differential diagnosis of thyroid carcinoma. Presurgical serum thyroglobulin levels did not differ among patients with tumor limited to thyroid gland or extending to cervical lymph nodes or invading outside the thyroid capsule or metastasising to distant size. In addition presurgical serum thyroglobulin levels were not correlated with the disease outcome after a mean follow-up of 9 years: no difference was found among patients in complete remission or with persistent disease or dead from thyroid cancer. In conclusion, this study failed to show any prognostic value of presurgical serum thyroglobulin determination that consequently should not be measured.