Francesco Trimarchi

BRAF(V600E) mutation and the biology of papillary thyroid cancer

BRAF((V600E)) mutation is the most frequent genetic alteration in papillary thyroid carcinomas (PTCs) that are 80-90% of all thyroid cancers. We evaluated the relationship between BRAF((V600E)) and tumor, host, and environmental factors in PTCs from all geographical areas of Sicily. By PCR, BRAF((V600E)) was investigated in a series of 323 PTCs diagnosed in 2002-2005. The correlation between clinicopathological tumor, host, and environmental characteristics and the presence of BRAF((V600E)) were evaluated by both univariate and multivariate analyses. BRAF((V600E)) was found in 38.6% PTCs, with a 52% frequency in the classical PTCs and 26.4% in the tall cell variant. Univariate analysis indicated that BRAF((V600E)) was associated with greater tumor size (P=0.0048), extra-thyroid invasion (P<0.0001), and cervical lymph nodal metastases (P=0.0001). Multivariate logistic regression analysis confirmed that BRAF((V600E)) was an independent predictor of extra-thyroid invasion (P=0.0001) and cervical lymph nodal metastasis (P=0.0005). The association between BRAF((V600E)) and extra-thyroid invasion was also found in micro-PTCs (P=0.006). In 60 classical PTCs, BRAF((V600E)) was positively correlated with matrix metalloproteinase-9 expression (P=0.0047), suggesting a possible mechanism for BRAF((V600E)) effect on PTC invasiveness. No association was found between BRAF((V600E)) and patient age, gender, or iodine intake. In contrast, a strong association was found with residency in Eastern Sicily (P<0.0001 compared with Western Sicily). These results indicate that BRAF((V600E)) mutation is a marker of aggressive disease in both micro- and macro-PTCs. Moreover, for the first time, a possible link between BRAF((V600E)) mutation and environmental carcinogens is suggested.

Altered intestinal absorption of L-thyroxine caused by coffee.

OBJECTIVE To report eight case histories, and in vivo and in vitro studies showing coffees potential to impair thyroxine (T4) intestinal absorption. DESIGN Of eight women with inappropriately high or nonsuppressed thyroid-stimulating hormone (TSH) when T4 was swallowed with coffee/espresso, six consented to the evaluation of their T4 intestinal absorption. This in vivo test was also administered to nine volunteers. In three separate tests, two 100 microg T4 tablets were swallowed with coffee, water, or water followed, 60 minutes later, by coffee. Serum T4 was assayed over the 4-hour period of the test. Two patients and two volunteers also agreed on having tested the intestinal absorption of T4 swallowed with solubilized dietary fibers. In the in vitro studies, classical recovery tests on known concentrations of T4 were performed in the presence of saline, coffee, or known T4 sequestrants (dietary fibers, aluminium hydroxide, and sucralfate). MAIN OUTCOME For the in vivo test, average and peak incremental rise of serum T4 (AIRST4 and PIRST4), time of maximal incremental rise of serum T4 (TMIRST4), and area under the curve (AUC) were determined. In patients and volunteers, the four outcome measures were similar in the water and water + coffee tests. In patients and volunteers, compared to water, coffee lowered AIRST4 (by 36% and 29%), PIRST4 (by 30% and 19%), and AUC (by 36% and 27%) and delayed TMIRST4 (by 38 and 43 minutes); bran was a superior interferer. In the in vitro studies, coffee was weaker than known T4 sequestrants. CONCLUSION Coffee should be added to the list of interferers of T4 intestinal absorption, and T4 to the list of compounds whose absorption is affected by coffee.

Papillary Thyroid Cancer Incidence in the Volcanic Area of Sicily

BACKGROUND The steadily increasing incidence of thyroid cancer has been attributed mostly to more sensitive thyroid nodule screening. However, various environmental factors, such as those associated with volcanic areas, cannot be excluded as risk factors. We evaluated thyroid cancer incidence in Sicily, which has a homogenous population and a province (Catania) that includes the Mt Etna volcanic area. METHODS In a register-based epidemiological survey, we collected all incident thyroid cancers in Sicily from January 1, 2002, through December 31, 2004. The age-standardized incidence rate for the world population (ASR(w)) was calculated and expressed as the number of thyroid cancer diagnoses per 100 000 residents per year. The association of thyroid cancer incidence rate with sex, age, tumor histotype, and various environmental factors was evaluated by modeling the variation of the ASR(w). All statistical tests were two-sided. RESULTS In 2002-2004, 1950 incident thyroid cancers were identified in Sicily (among women, ASR(w) = 17.8, 95% confidence interval [CI] = 16.9 to 18.7; and among men, ASR(w) = 3.7, 95% CI = 3.3 to 4.1). Although the percentage of thyroid cancers that were microcarcinomas (ie, < or = 10 mm) and ratio of men to women with thyroid cancer were similar in all nine Sicilian provinces, thyroid cancer incidence was statistically significantly higher in the province of Catania (among women, ASR(w) = 31.7, 95% CI = 29.1 to 34.3; and among men, ASR(w) = 6.4, 95% CI = 5.2 to 7.5) than in the rest of Sicily (among women, ASR(w) = 14.1, 95% CI = 13.2 to 15.0; and among men, ASR(w) = 3.0, 95% CI = 2.6 to 3.4) (all P values < .001). Incidence of papillary, but not follicular or medullary, cancers was statistically significantly increased in Catania province, and papillary tumors from patients in Catania more frequently carried the BRAF V600E gene mutation (55 [52%] of 106 tumors) than tumors from patients elsewhere in Sicily (68 [33%] of 205 tumors) (relative risk = 1.7, 95% CI = 1.0 to 2.8, P = .02). Cancer incidence was statistically significantly lower in rural areas than in urban areas of Sicily (P = .003). No association with mild iodine deficiency or industrial installations was found. Levels of many elements (including boron, iron, manganese, and vanadium) in the drinking water of Catania province often exceeded maximum admissible concentrations, in contrast to water in the rest of Sicily. CONCLUSION Residents of Catania province with its volcanic region appear to have a higher incidence of papillary thyroid cancer than elsewhere in Sicily.

Cabergoline: a first-choice treatment in patients with previously untreated prolactin-secreting pituitary adenoma.

Cabergoline (CAB) treatment is an effective, safe and well tolerated approach for hyperprolactinemia. We investigated the efficacy of 24-month treatment with CAB in 37 patients with previously untreated PRL-secreting pituitary adenoma and evaluated the hormonal and neuroradiological changes after the discontinuation of long-term therapy. Eleven patients with macroprolactinoma (1M/10F) and 26 with microprolactinoma (4M/22F) started treatment taking 0.25 mg CAB twice a week for 4 weeks. The dose was increased stepwise in 0.5 mg increments until reaching lowest maximally effective and tolerated dose. CAB was withdrawn before the end of the study in 6 women who became pregnant and in one patient who showed a slight increase of the macroadenoma at MRI. During treatment, PRL levels decreased significantly in macro (11.1±1.1 vs 407.8±98.3 μg/l, p<0.001) and microprolactinomas (11.1±1.6 vs 193.8±23.4 μg/l, p<0.05) and normalized in all macro and in 23/26 microprolactinomas. In 3 cases PRL levels decreased but did not normalize because the appearance of side effects, such as nausea or hypotension, prevented the increase of the dose of CAB. The effective dose of drug correlated significantly with basal serum PRL levels (p<0.05) and with the pituitary tumor size (p<0.05). A significant decrease of the mean adenoma size was evident for macro (6.9±1.8 vs 16.0±1.8 mm, p<0.001) and microprolactinomas (3.0±0.5 vs 6.5±0.4 mm, p<0.001) at MRI. The tumor disappeared in 4 macroadenomas and in 11 microadenomas after 12 months of treatment. CAB withdrawal was followed by serum PRL increase in 13 cases after 3 months, in 6 after 6 months, in 2 after 9 months, and in one patient at the 12th month. Five patients showed normo-prolactinemia with negative MRI after one year. Regular menses were restored in 7/10 macro-prolactinomas and in all oligo-amenorrhoic patients with microadenoma; serum testosterone levels normalized in 2/3 hypogonadic men. Five out of 6 women become pregnant and had uneventful pregnancies which resulted in deliveries of normal babies. In conclusion, this study confirms the effectiveness and safety of CAB for patients with PRL-secreting pituitary adenoma and suggests that it can be considered a first choice treatment.

Iodine Prophylaxis Using Iodized Salt and Risk of Maternal Thyroid Failure in Conditions of Mild Iodine Deficiency

CONTEXT Mild to moderate iodine deficiency during pregnancy can cause transient maternal hypothyroidism and impaired mental development of the progeny. These unfavorable effects are preventable by iodine supplementation. In Europe, however, less than 50% pregnant women receive iodine-containing supplements, thus representing dietary iodized salt the only carrier of iodine for most women in this life stage. OBJECTIVE/DESIGN This longitudinal study is aimed to investigate the effects of long-term iodized salt consumption on maternal thyroid function during gestation. PARTICIPANTS/OUTCOME MEASURES: We prospectively evaluated thyroid function in 100 consecutive thyroperoxidase antibody-negative pregnant women from a mildly iodine-deficient area. Sixty-two women who had regularly used iodized salt for at least 2 yr prior to becoming pregnant and 38 who commenced iodized salt consumption upon becoming pregnant were classified as long-term (LT) and short-term (ST) iodine supplemented, respectively. RESULTS Long-term iodized salt consumption resulted in a very low prevalence of maternal thyroid failure (MTF) in LT women. Conversely, short-term iodine prophylaxis does not seem to protect against the risk of MTF, the prevalence of which was almost 6-fold higher in ST than LT women (36.8% vs. 6.4%; chi(2) 14.7, P < 0.0005; relative risk 5.7, 95% confidence interval 2.03-16.08, P < 0.001). The relative risk reduction amounted to 82.5%, this measure indicating the extent to which long-term iodine prophylaxis using iodized salt would reduce the risk of MTF in ST women. CONCLUSIONS Prolonged iodized salt significantly improves maternal thyroid economy and reduces the risk of maternal thyroid insufficiency during gestation, probably because of a nearly restoring intrathyroidal iodine stores.

Maternal hypothyroxinaemia during the first half of gestation in an iodine deficient area with endemic cretinism and related disorders

OBJECTIVE Iodine deficiency is well known as the cause of several disorders such as endemic goitre and cretinism, along with a wide spectrum of psychoneurological development disorders including endemic mental deficiency and endemic cognitive deficiency, which are generally correlated to damage to the fetus. Such damage Is, by Inference, deemed a consequence either directly of iodine deficiency or of insufficient availability of thyroxine at the feto‐placental unit level. Early pregnancy represents the crucial period for neurogenesis in the embryo. Several experimental studies have emphasized the direct role of maternal T4 in neurological embryo‐genesis, before the onset of fetal thyroid function and, therefore, Its protective role In fetal thyroid failure. The objective of this study was to evaluate whether Iodine deficiency may Influence thyroid status of pregnant women throughout the first half of pregnancy.

Genetic Alterations in the Ras/Raf/Mitogen-Activated Protein Kinase and Phosphatidylinositol 3-Kinase/Akt Signaling Pathways in the Follicular variant of Papillary Thyroid Carcinoma

The follicular variant of papillary thyroid carcinoma (FVPTC) is the second most common histotype among papillary thyroid cancers (PTCs). Although the prognosis of FVPTC is similar to the conventional phenotype, differential diagnostic difficulties may not be uncommon with other follicular thyroid neoplasms, and little is known about their genetic alterations. Defining these alterations may lead to the identification of diagnostic and biologic markers.

Gestational thyroid function abnormalities in conditions of mild iodine deficiency: early screening versus continuous monitoring of maternal thyroid status

OBJECTIVE To longitudinally evaluate the timing of maternal thyroid underfunction occurrence in mildly iodine-deficient (ID) pregnant women, and ultimately assess the benefit of thyroid function testing at early gestation only in identifying maternal thyroid underfunction. PARTICIPANTS/METHODS Serum free-thyroxine and TSH were measured in 220 consecutive women once in early pregnancy (by week 12) and twice per trimester subsequently. Anti-thyroperoxidase and anti-thyroglobulin were also determined at initial and final observation. RESULTS Thyroid autoantibodies were detectable in 8.2% women. Overall, the prevalence of hypothyroidism over the course of gestation was 11.8% (26/220), with a relative risk of hypothyroidism in antibody-positive women of 5.0 (chi(2) 20.02, P<0.0005). Nonetheless, almost 70% hypothyroid women tested negative for thyroid autoantibodies. Fifteen/26 (57.7%) hypothyroid women were identified at presentation, and the remaining 11 at either early (6/11) or late (5/11) phases of the 2nd trimester. Isolated hypothyroxinemia was observed in 56/220 (25.4%) women, mostly from the 2nd trimester onwards. CONCLUSIONS In mildly ID areas thyroid function testing early in gestation seems to be only partly effective in identifying thyroid underfunction in pregnant women. Indeed, in our series more than 40% hypothyroid women would not have been diagnosed had we limited our observation to early thyroid function tests alone. Although thyroid autoimmunity carried a 5-fold increased risk of hypothyroidism, iodine deficiency seems to be a major determinant in the occurrence of thyroid underfunction. Adequate iodine supplementation should be strongly recommended to meet the increased hormone demand over gestation.

Changed presentation of Hashimoto's thyroiditis in North-Eastern Sicily and Calabria (Southern Italy) based on a 31-year experience.

OBJECTIVE To quantify the yearly prevalence of Hashimotos thyroiditis at our Division and evaluate changes in its clinical presentation over the period 1975-2005. DESIGN We have reviewed retrospectively the clinical records of patients admitted to a university hospital located in Messina, Sicily (Italy), from January 1, 1975, through December 31, 2005. This facility attracts patients from North-Eastern Sicily and most of Calabria, the Italian region across the Straits. HT was diagnosed based on various combinations of clinical, laboratory, and instrumental findings. The study group consisted of 4064 HT patients diagnosed during these 31 years. MAIN OUTCOME We evaluated these indexes on a yearly basis: number of new HT diagnoses; age at presentation; male-to-female ratio; functional status; goitrous or nongoitrous variants with or without nodule(s); above-normal titers or levels of serum thyroid autoantibodies (thyroglobulin antibodies and thyroperoxidase antibodies). Several indexes have changed over those 31 years. Particularly, HT has become 10 times more common than it was until the early 1990s and males are relatively more represented. Patients are relatively younger, with a nongoitrous thyroid; the rate of S-Hypo exceeds largely the rate of O-Hypo. Serum thyroid autoantibodies have become less frequently positive, and when positive, they are present at a lower concentration. CONCLUSIONS Only environmental changes, as opposed to genetic changes, can account for such alterations in the presentation of HT in our geographical area.

Clinical presentation and outcome of pituitary adenomas in teenagers

objective Pituitary adenomas rarely occur in childhood and adolescence, but their mass effect and endocrine abnormalities can compromise both quality and length of life. In this study we evaluated the symptoms at onset and the long‐term consequences induced in teenagers by functioning or nonfunctioning pituitary adenomas.