Lack of association between thyroid and adrenal nodules: a histological study

Adrenal Incidentalomas and Other Endocrine-Related Adenomas: How Much Does Cortisol Secretion Matter?

Background: Adrenal incidentalomas (AI) are frequent findings in clinical practice. About 40% of AIs are associated with hypercortisolism of variable severity. Although mild autonomous cortisol secretion (MACS) has been associated with the impaired clinical outcome of several diseases, its effect on the development of benign neoplasms is unknown. Aim: To compare the prevalence of adenomas (thyroid, parathyroid, pituitary and other locations) in patients with nonfunctioning AIs (NFAIs) and MACS. Methods: A multicenter, retrospective study of patients with AIs evaluated in four tertiary hospitals was performed. Results: A total of 923 patients were included. Most patients were male (53.6%), with a mean age at diagnosis of 62.4 ± 11.13 years; 21.7% presented with bilateral AIs. MACS was observed in 29.9% (n = 276) of patients, while 69.9% (n = 647) were NFAIs. Adenomas in locations other than the adrenal gland were observed in 36% of the studied population, with a similar distribution in patients with MACS and NFAIs (33% vs. 32%; p > 0.05). There were no statistically significant differences in the prevalence of pituitary, thyroid, parathyroid or other endocrine-related adenomas between both groups, but the prevalence of metabolic comorbidities and mortality was increased in patients with MACS, specifically in patients with thyroid and other endocrine-related adenomas (p < 0.05). Conclusions: Adenomas in locations other than the adrenal glands occur in one third of patients with AIs. Mild autonomous hypercortisolism does not affect the prevalence of other endocrine-related adenomas but is associated with increased metabolic comorbidities and mortality, especially in patients with thyroid adenomas and adenomas in other locations.

Minimally invasive techniques in benign and malignant adrenal tumors

Minimally invasive adrenalectomy has become the main treatment modality for most adrenal lesions. Both laparoscopic transabdominal and retroperitoneoscopic approaches are safe and feasible options, each with respective advantages, including better surgical outcomes, fewer complications, and faster recovery over open adrenalectomy. While open surgery remains a valid modality in treatment of adrenocortical cancer in the presence of some findings such as invasion, robotic platforms, and minimally invasive surgery have gained popularity as technology continues to evolve. Organ preservation during adrenalectomy is feasible in some conditions to prevent adrenal insufficiency. Ablative technologies are increasingly utilized in benign and malignant tumors, including the adrenal gland, with various outcomes. A multidisciplinary team, an experienced surgeon, and a high-volume center are recommended for any surgical approaches and management of adrenal lesions. This review article evaluated recent findings and current evidence on minimally invasive adrenalectomy.

Adrenal Incidentaloma

An adrenal incidentaloma is now established as a common endocrine diagnosis that requires a multidisciplinary approach for effective management. The majority of patients can be reassured and discharged, but a personalized approach based upon image analysis, endocrine workup, and clinical symptoms and signs are required in every case. Adrenocortical carcinoma remains a real concern but is restricted to <2% of all cases. Functional adrenal incidentaloma lesions are commoner (but still probably <10% of total) and the greatest challenge remains the diagnosis and optimum management of autonomous cortisol secretion. Modern-day surgery has improved outcomes and novel radiological and urinary biomarkers will improve early detection and patient stratification in future years to come.

Epidemiology of nodular goitre. Influence of iodine intake

More than one tenth of the world population is to some degree affected by goitre and most of these harbour nodules. The large differences in thyroid disease prevalence between populations may be caused by genetic and environmental factors. Among the latter, iodine deficiency seems by far to be the most important risk factor. Thus, nodular goitre is a condition predominantly seen in iodine deficient areas of the world. In the present review, we evaluated in detail autopsy and ultrasound studies of the thyroid gland. In autopsy studies, large thyroid volumes and high frequencies of goitres have been reported in countries affected by iodine deficiency. Many cross-sectional studies using thyroid ultrasound investigations have been performed world-wide and reported high thyroid volumes and goitre prevalences, and to some extent also high prevalences of thyroid nodules in iodine-deficient countries. Most of these goitres were classified as nodular goitres. On the other hand, few studies have shown that abundant iodine intake may lead to development of diffuse goitres, but world-wide this has been a minor problem compared with development of nodular goitres. In the past century we have observed a trend towards smaller thyroid glands, and hopefully less than 10% of the world population will experience goitre within a few decades.

Relationship between thyroid nodules and non-functioning adrenal incidentalomas and their association with insulin resistance

OBJECTIVE

The relationship between insulin resistance and thyroid nodules in patients with non-functional adrenal incidentalomas (AI) is not clearly understood. The aim of this study was to determine the frequency of thyroid nodules in AI patients, as well as to evaluate any possible associations with disorders of insulin resistance.

METHODS

Patients diagnosed with a non-functional AI were approached for inclusion in the study. Insulin resistance was evaluated using homeostasis model assessment (HOMA-IR). All participants were screened for the presence of thyroid nodule by ultrasonography, and fine needle aspiration biopsies were obtained from consenting subjects.

RESULTS

One-hundred-thirteen patients with AI and 152 age-, BMI- and gender-matched healthy controls were enrolled. AI patients had higher waist circumference and waist/hip ratio than the control group. Metabolic syndrome, hypertension and type 2 diabetes mellitus rates were significantly higher in AI patients. HOMA-IR was similar between the groups. At least one thyroid nodule was observed in 42 (27.6%) of the controls compared to 55 (48.7%) of AI patients (p < 0.001). The mean number of thyroid nodules in AI patients was significantly higher than the control subjects (2.4 ± 0.9 versus 1.7 ± 1.0, p = 0.008). Mean nodule volume was similar between AI patients and the controls. A correlation could not be established between adrenal tumor/thyroid nodule volumes and the number of thyroid nodules, HOMA-IR, waist circumference, waist/hip ratio, BMI and thyroid function tests.

CONCLUSION

A higher prevalence of thyroid nodule and a higher number of thyroid nodules were determined in patients with AI compared to healthy controls.