Clinical aggressiveness of incidental and non-incidental thyroid cancer.

BACKGROUND: With the increasing use of thyroid ultrasound, the recognition of thyroid nodules in a large proportion of apparently healthy subjects has become common. Because also the papillary thyroid microcarcinomas (PTMC) are being increasingly discovered, it is important to ascertain whether PTMC may exhibit heterogenous clinical features, associated with different aggressiveness. AIM: We retrospectively examined 122 subjects [98 female (80.3%), and 24 male (19.7%)] with thyroid cancer to find potential clinical and pathological findings that could be predictive of clinically aggressive behavior. RESULTS: Twenty of the 31 patients with true incidental cancer (64.5%) in comparison to 20 of the 91 patients with non-incidental cancer (21.9%) had a diameter <10 mm, and this difference was statistically significant (p<0.0001). There was a statistically significant association between size and invasiveness because 19.3% of invasive cancers were <10 mm whereas 44.6% of non-invasive cancers were <10 mm (p=0.005). The relationship between incidental discovery and invasiveness was also evaluated, but the proportion of incidental invasive cancer (19.3%) was not significantly different from that of incidental non-invasive cancer (30.8%). In the multivariate analysis, only size <10 mm (odds ratio=0.35, p=0.013) and papillary vs other histotypes (odds ratio=0.35, p=0.04) were statistically significant protective factors against invasiveness. CONCLUSIONS: a) Incidentally discovered thyroid cancers are more frequently microcarcinomas; b) there appears to be no difference in terms of invasive behavior between incidental and non-incidental thyroid cancer; c) smaller tumor size emerges as a protective factor.

C-reactive protein is independently associated with total body fat, central fat, and insulin resistance in adult women.

OBJECTIVE: To investigate whether C-reactive protein (CRP) concentrations are influenced by body composition, insulin resistance, and body fat distribution in healthy women. DESIGN: Cross-sectional study of CRP plasma levels in adult women. SUBJECTS: A total of 201 apparently healthy normal weight, overweight, and obese women, aged 18-60 y. MEASUREMENTS: CRP plasma levels, several fatness and body fat distribution parameters (by bioimpedance analysis and anthropometry), and insulin resistance (HOMA(IR)), as calculated by homeostatic model assessment. RESULTS: CRP was positively correlated with age, body mass index (BMI), waist, fasting glucose and insulin, HOMA(IR), fat-free mass (FFM) and fat mass (FM). After multivariate analyses, age, HOMA(IR), waist and FM maintained their independent association with CRP. CONCLUSION: Our study has shown an independent relationship of central fat accumulation and insulin resistance with CRP plasma levels, thus suggesting that mild, chronic inflammation may be a further component of the metabolic syndrome and a mediator of the atherogenic profile of this syndrome.

Plasma leptin is independently associated with the intima-media thickness of the common carotid artery.

OBJECTIVE: To investigate whether intima-media thickness (IMT) of the common carotid artery (CCA), an early marker of asymptomatic atherosclerosis, is significantly and independently associated with plasma concentrations of leptin, an adipose tissue hormone that has recently been proposed as a cardiovascular risk factor in obese patients. DESIGN: Cross-sectional sample of normal-weight and obese men and women. SUBJECTS: One-hundred and twenty healthy subjects (52 men and 68 women), aged 18-45 y and with a wide range of BMI, were recruited for the study. MEASUREMENTS: Fasting plasma leptin concentrations and the IMT of the CCA were measured in all subjects. Leptin concentrations were measured by radioimmunoassay and the IMT of the CCA was quantified by high resolution B-mode ultrasound imaging. Central fat (measured by waist circumference), smoking habits, blood pressure, insulin sensitivity (measured by the insulin tolerance test), and fasting plasma glucose, insulin and lipid pattern (cholesterol, HDL-cholesterol, triglycerides, LDL-cholesterol) were also measured. RESULTS: IMT of the CCA was positively correlated with log leptin concentrations (P<0.005 in men and P<0.001 in women), body mass index (P<0.001 in men and women), waist circumference (P<0.001 in men and women), age (P<0.001 in men and P<0.05 in women), and negatively associated with insulin sensitivity in both sexes (P<0.05). IMT was also directly correlated with cholesterol (P<0.05), LDL-cholesterol (P<0.01) and systolic blood pressure in men (P<0.05), and with diastolic blood pressure levels in women (P<0.05). When a multiple linear regression model was used without body mass index (BMI), the correlation between leptin and IMT was maintained in both men (P<0.01) and women (P<0.005), independent of age, insulin sensitivity, smoking habits, systolic blood pressure, fasting glucose, triglycerides, cholesterol, LDL-cholesterol and HDL-cholesterol. By contrast, BMI-adjusted leptin concentrations were not significantly associated with IMT (Pc (partial correlation): 0.41 in men and 0.15 in women). Moreover, when BMI was entered into a multiple linear regression model without leptin, the correlation between BMI and IMT was maintained in both men (P<0.005) and women (P<0.01), independent of the same parameters. CONCLUSION: Plasma leptin concentrations are independently associated with the IMT of the CCA, suggesting that the increase of adipose tissue mass (or leptin per se) may have an unfavourable influence on the development of atherosclerosis. However, the association between IMT and leptin seems to be dependent and/or confounded by the relationship between IMT and obesity.

Urinary albumin excretion is independently associated with C-reactive protein levels in overweight and obese nondiabetic premenopausal women.

OBJECTIVES: C-reactive protein (CRP) and microalbuminuria are nowadays considered markers of chronic inflammation of the arterial wall and of endothelial dysfunction, respectively. An increase of CRP levels and of urinary albumin excretion (UAE) rate have both been reported to be independently associated with a higher risk of cardiovascular morbidity and mortality in the general population. The aim of the present study was to evaluate the possible correlation between UAE and CRP concentrations in overweight and obese premenopausal women. DESIGN AND SETTING: A cross-sectional study in a primary care setting. SUBJECTS, MAIN OUTCOME MEASURES: CRP levels and UAE rate were measured in 103 overweight and obese premenopausal women, aged 18-45 years. Other measurements included: central fat accumulation, as evaluated by waist circumference, insulin resistance, as calculated by homeostatic model assessment (HOMAIR); fat-free mass (FFM), as measured by bioimpedance analysis; blood pressure; and fasting plasma levels of glucose, insulin, and lipids. RESULTS: Urinary albumin excretion was positively correlated with body mass index (BMI) (P < 0.01), waist circumference (P < 0.001), diastolic blood pressure (P < 0.01), triglycerides (P < 0.01), HOMAIR (P < 0.05), and CRP levels (P < 0.05); and negatively associated with HDL cholesterol (P < 0.001). After multivariate analysis, diastolic blood pressure, HDL cholesterol, and CRP levels maintained their significant correlation with UAE. CONCLUSION: Our study shows a strong relationship between UAE and CRP concentrations, irrespective of age and other anthropometric and metabolic variables. On this basis, it can be argued that inflammation of the arterial wall, as indicated by higher CRP plasma levels, and endothelial dysfunction, as shown by higher UAE rate, might represent simultaneous phenomena in the development of atherosclerosis in overweight and obese premenopausal women.