PITUITARY IMAGING BY MRI AND ITS CORRELATION WITH BIOCHEMICAL PARAMETERS IN THE EVALUATION OF MEN WITH HYPOGONADOTROPIC HYPOGONADISM.

Objective: A significant ambiguity still remains about which patient deserves a magnetic resonance imaging (MRI) scan of the pituitary during evaluation of hypogonadotropic hypogonadism (HH) in men. Methods: Retrospective case series of 175 men with HH referred over 6 years. Results: A total of 49.7% of men had total testosterone (TT) levels lower than the Endocrine Society threshold of 5.2 nmol/L. One-hundred forty-two patients (81.2%) had normal appearance of pituitary MRI, whereas others had different spectrum of abnormalities (empty sella [n = 16], macroadenoma [n = 8], microadenoma [n = 8], and pituitary cyst [n = 1]). In men with TT in the lowest quartile, MRI pituitary findings were not significantly different from men in the remaining quartiles (P = .50). Patients with raised prolactin had higher number of abnormal MRI findings (38.9% vs. 13.7%; P = .0014) and adenomatous lesions (macro and micro) (27.8% vs. 4.3%; P = .01) in comparison to men with normal prolactin. The prolactin levels (median [interquartile range]) were highest in men with macroadenomas in both groups (9,950 [915]; P = .007 and 300 [68.0] mU/L; P = .02, respectively), with concomitant lower levels of other pituitary hormones. Multivariate logistic regression showed an association of abnormal pituitary MRI with insulin-like growth factor 1 (IGF-1) standard deviation score (SDS) (odds ratio [OR], 1.78 [95% confidence interval (CI), 1.15 to 2.77]; P = .009) and prolactin (OR, 1.00 [95% CI, 1.00 to 1.03]; P = .01). Conclusion: MRI of the pituitary is not warranted in all patients with HH, as the yield of identifiable abnormalities is quite low. Anatomic lesions are likely to be present only when low levels of TT (<5.2 nmol/L) are found concomitantly with high levels of prolactin and/or low IGF-1 SDS. Abbreviations: CI = confidence interval; FT4 = free thyroxine; GH = growth hormone; HH = hypogonadotropic hypogonadism; IGF-1 = insulin-like growth factor; LH = luteinizing hormone; MRI = magnetic resonance imaging; OR = odds ratio; SDS = standard deviation score; TSH = thyroid-stimulating hormone; TT = total testosterone.

Primary therapy of Graves' disease and cardiovascular morbidity and mortality: a linked-record cohort study.

BACKGROUND: Graves' disease is routinely treated with antithyroid drugs, radioiodine, or surgery, but whether the choice of initial therapy influences long-term outcomes is uncertain. We evaluated cardiovascular morbidity and mortality according to the method and effectiveness of primary therapy in Graves' disease. METHODS: In this retrospective cohort study, we identified patients with hyperthyroidism, diagnosed between Jan 1, 1998, and Dec 31, 2013, from a thyroid-stimulating hormone (TSH)-receptor antibody (TRAb) test register in south Wales, UK, and imported their clinical data into the All-Wales Secure Anonymised Information Linkage (SAIL) Databank (Swansea University, Swansea, UK). Patients with Graves' disease, defined by positive TRAb tests, were selected for the study, and their clinical data were linked with outcomes in SAIL. We had no exclusion criteria. Patients were matched by age and sex to a control population (1:4) in the SAIL database. Patients were grouped by treatment within 1 year of diagnosis into the antithyroid drug group, radioiodine with resolved hyperthyroidism group (radioiodine group A), or radioiodine with unresolved hyperthyroidism group (radioiodine group B). We used landmark Kaplan-Meier and Cox regression models to analyse the association of treatment with the primary outcome of all-cause mortality and the secondary outcome of major adverse cardiovascular events (myocardial infarction, heart failure, ischaemic stroke, or death) with the landmark set at 1 year after diagnosis. We analysed the association between outcomes and concentration of TSH using Cox regression and outcomes and free thyroxine (FT4) concentration using restricted cubic-spline regression models. FINDINGS: We extracted patient-level data on 4189 patients (3414 [81·5%] females and 775 [18·5%] males) with Graves' disease and 16 756 controls (13 656 [81·5%] females and 3100 [18·5%] males). In landmark analyses, 3587 patients were in the antithyroid drug group, 250 were in radioiodine group A, 182 were in radioiodine group B. Patients had increased all-cause mortality compared with controls (hazard ratio [HR] 1·22, 95% CI 1·05-1·42). Compared with patients in the antithyroid drug group, mortality was lower among those in radioiodine group A (HR 0·50, 95% CI 0·29-0·85), but not for those in radioiodine group B (HR 1·51, 95% CI 0·96-2·37). Persistently low TSH concentrations at 1 year after diagnosis were associated with increased mortality independent of treatment method (HR 1·55, 95% CI 1·08-2·24). Spline regressions showed a positive non-linear relationship between FT4 concentrations at 1 year and all-cause mortality. INTERPRETATION: Regardless of the method of treatment, early and effective control of hyperthyroidism among patients with Graves' disease is associated with improved survival compared with less effective control. Rapid and sustained control of hyperthyroidism should be prioritised in the management of Graves' disease and early definitive treatment with radioiodine should be offered to patients who are unlikely to achieve remission with antithyroid drugs alone. FUNDING: National Institute for Social Care and Health Research, Wales.

Predicting malignancy in thyroid nodules: feasibility of a predictive model integrating clinical, biochemical, and ultrasound characteristics.

BACKGROUND: Although the majority of thyroid nodules are benign the process of excluding malignancy is challenging and sometimes involves unnecessary surgical procedures. We explored the development of a predictive model for malignancy in thyroid nodules by integrating a combination of simple demographic, biochemical, and ultrasound characteristics. METHODS: Retrospective case-record review. We reviewed records of patients with thyroid nodules referred to our institution from 2004 to 2011 (n = 536; female 84 %, mean age 51 years). All malignancy was proven histologically while benign disease was either confirmed histologically, or on cytology with minimum 36-month observation period. We focused on the following predictors: age, sex, smoking status, thyroid hormones (FT4 and TSH) and nodule characteristics on ultrasound. Variables were included in a multivariate logistic regression and bootstrap analyses were used to confirm results. RESULTS: Independent predictors of malignancy in the fully adjusted model were TSH (OR 1.53, 95 % CI 1.10, 2.12, p = 0.01), male gender (OR 3.45, 95 % CI 1.33, 8.92, p = 0.01), microcalcifications (OR 6.32, 95 % CI 2.82, 14.1, p < 0.001), and irregular nodule margins (OR 5.45, 95 % CI 1.61, 18.6, p = 0.006) Bootstrap analyses strengthened these associations and a parsimonious analysis consisting of these variables and age-group demonstrated an area under the curve of 0.77. A predictive score was sensitive (86.9 %) at low scores and highly specific (94.87 %) at higher scores for distinguishing benign from malignant disease. CONCLUSIONS: A predictive model for malignancy using a combination of clinical, biochemical, and radiological characteristics may support clinicians in reducing unnecessary invasive procedures in patients with thyroid nodules.