Metabolic syndrome (MetS) is a complex disorder defined by a cluster of interconnected factors that increase the risk of cardiovascular atherosclerotic diseases and diabetes mellitus type 2. Currently, several different definitions of MetS exist, causing substantial confusion as to whether they identify the same individuals or represent a surrogate of risk factors. Recently, a number of other factors besides those traditionally used to define MetS that are also linked to the syndrome have been identified. In this review, we critically consider existing definitions and evolving information, and conclude that there is still a need to develop uniform criteria to define MetS, so as to enable comparisons between different studies and to better identify patients at risk. As the application of the MetS model has not been fully validated in children and adolescents as yet, and because of its alarmingly increasing prevalence in this population, we suggest that diagnosis, prevention and treatment in this age group should better focus on established risk factors rather than the diagnosis of MetS.

Only advances that occurred from 2011 to 2014 that either strengthen the previous 2011 guidelines [1,2] or lead to changes or additional guidelines are reviewed here. Advances and modifications in the treatment of advanced metastatic disease is only briefly dealt with here as it is covered in a separate paper in this issue, similar to the 2011 guideline format [3]. The format used here is the same as that used in the 2011 guidelines with page references to the appropriate paper inserted [1,2]. This document is meant as a supplement to these guidelines and does not reiterate all of the points made in the previous guidelines, only changes, supporting findings or modifications of the 2011 guidelines are thus covered here.

The criteria for the diagnosis of the polycystic ovary syndrome (PCOS) have still not been agreed universally. A population of 1741 women with PCOS were studied, all of whom had polycystic ovaries seen by ultrasound scan. The frequency distributions of the serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone and prolactin and the body mass index, ovarian volume, uterine cross-sectional area and endometrial thickness were determined and compared with the symptoms and signs of PCOS. Obesity was associated with hirsutism and an elevated serum testosterone concentration and was also correlated with increased rates of infertility and cycle disturbance. The rates of infertility and cycle disturbance also increased with serum LH concentrations >10 IU/l. A rising serum concentration of testosterone [mean and 95th percentiles 2.6 (1.1–4.8) nmol/1] was associated with an increased risk of hirsutism, infertility and cycle disturbance. The ovarian volume was correlated with serum concentrations of testosterone, LH and the body mass index, which was also correlated with the uterine area. This descriptive data from the largest reported series of women with PCOS enables the development of a management-orientated approach to the syndrome. Women who are overweight can expect an improvement in their symptoms if they lose weight. An elevated concentration of LH (>10 IU/1) is associated with infertility and treatment should be chosen accordingly. If the serum testosterone concentration is >4.8 nmol/l, other causes of hyperandrogenism should be excluded.

Pulmonary carcinoids (PCs) are rare tumors. As there is a paucity of randomized studies, this expert consensus document represents an initiative by the European Neuroendocrine Tumor Society to provide guidance on their management. Bibliographical searches were carried out in PubMed for the terms ‘pulmonary neuroendocrine tumors’, ‘bronchial neuroendocrine tumors’, ‘bronchial carcinoid tumors’, ‘pulmonary carcinoid’, ‘pulmonary typical/atypical carcinoid’, and ‘pulmonary carcinoid and diagnosis/treatment/epidemiology/prognosis’. A systematic review of the relevant literature was carried out, followed by expert review. PCs are well-differentiated neuroendocrine tumors and include low- and intermediate-grade malignant tumors, i.e. typical (TC) and atypical carcinoid (AC), respectively. Contrast CT scan is the diagnostic gold standard for PCs, but pathology examination is mandatory for their correct classification. Somatostatin receptor imaging may visualize nearly 80% of the primary tumors and is most sensitive for metastatic disease. Plasma chromogranin A can be increased in PCs. Surgery is the treatment of choice for PCs with the aim of removing the tumor and preserving as much lung tissue as possible. Resection of metastases should be considered whenever possible with curative intent. Somatostatin analogs are the first-line treatment of carcinoid syndrome and may be considered as first-line systemic antiproliferative treatment in unresectable PCs, particularly of low-grade TC and AC. Locoregional or radiotargeted therapies should be considered for metastatic disease. Systemic chemotherapy is used for progressive PCs, although cytotoxic regimens have demonstrated limited effects with etoposide and platinum combination the most commonly used, however, temozolomide has shown most clinical benefit. PCs are complex tumors which require a multidisciplinary approach and long-term follow-up.

Neuroendocrine tumors (NETs) constitute a heterogeneous group of neoplasms that originate from endocrine glands such as the pituitary, the parathyroids, and the (neuroendocrine) adrenal, as well as endocrine islets within glandular tissue (thyroid or pancreatic) and cells dispersed between exocrine cells, such as endocrine cells of the digestive (gastroenteropancreatic) and respiratory tracts. Conventionally, NETs may present with a wide variety of functional or nonfunctional endocrine syndromes and may be familial and have other associated tumors. Assessment of specific or general tumor markers offers high sensitivity in establishing the diagnosis and can also have prognostic significance. Imaging modalities include endoscopic ultrasonography, computed tomography and magnetic resonance imaging, and particularly, scintigraphy with somatostatin analogs and metaiodobenzylguanidine. Successful treatment of disseminated NETs requires a multimodal approach; radical tumor surgery may be curative but is rarely possible. Well-differentiated and slow-growing gastroenteropancreatic tumors should be treated with somatostatin analogs or alpha-interferon, with chemotherapy being reserved for poorly differentiated and progressive tumors. Therapy with radionuclides may be used for tumors exhibiting uptake to a diagnostic scan, either after surgery to eradicate microscopic residual disease or later if conventional treatment or biotherapy fails. Maintenance of the quality of life should be a priority, particularly because patients with disseminated disease may experience prolonged survival.