Epidemiological link between obesity,type 2 diabetes mellitus and cancer

There exists a complex interaction between obesity,type 2 diabetes mellitus(T2DM)and cancer,and an increase in the incidence of cancer is expected with the growing obesity-diabetes pandemic.The association of cancer with diabetes mellitus and obesity appears to be site-specific,the highest risk being for postmenopausal breast cancer,endometrial cancer,and colorectal cancer.Moreover,there is worsening of hyperglycaemia with the onset of cancer,evidencing a bidirectional link between cancer and diabetes mellitus and the need for monitoring for diabetes in cancer survivors.In this review,we look at the epidemiological evidence from observational studies and Mendelian randomization studies linking obesity,diabetes,and cancer,as well as the complex pathophysiological mechanisms involved,including insulin resistance with associated hyperinsulinaemia,the effect of chronic low-grade inflammation,and the effect of various adipokines that are associated with obesity and T2DM.Additionally,we describe the novel therapeutic strategies,based on their role on the discrete pathophysiological mechanisms involved in the tumourigenesis.

Gastroenteropancreatic neuroendocrine neoplasms:A clinical snapshot

Our understanding about the epidemiological aspects,pathogenesis,molecular diagnosis,and targeted therapies of neuroendocrine neoplasms(NENs)have drastically advanced in the past decade.Gastroenteropancreatic(GEP)NENs originate from the enteroendocrine cells of the embryonic gut which share common endocrine and neural differentiation factors.Most NENs are welldifferentiated,and slow growing.Specific neuroendocrine biomarkers that are used in the diagnosis of functional NENs include insulin,glucagon,vasoactive intestinal polypeptide,gastrin,somatostatin,adrenocorticotropin,growth hormone releasing hormone,parathyroid hormone-related peptide,serotonin,histamine,and 5-hydroxy indole acetic acid(5-HIAA).Biomarkers such as pancreatic polypeptide,human chorionic gonadotrophin subunits,neurotensin,ghrelin,and calcitonin are used in the diagnosis of non-functional NENs.5-HIAA levels correlate with tumour burden,prognosis and development of carcinoid heart disease and mesenteric fibrosis,however several diseases,medications and edible products can falsely elevate the 5-HIAA levels.Organ-specific transcription factors are useful in the differential diagnosis of metastasis from an unknown primary of well-differentiated NENs.Emerging novel biomarkers include circulating tumour cells,circulating tumour DNA,circulating micro-RNAs,and neuroendocrine neoplasms test(NETest)(simultaneous measurement of 51 neuroendocrine-specific marker genes in the peripheral blood).NETest has high sensitivity(85%-98%)and specificity(93%-97%)for the detection of gastrointestinal NENs,and is useful for monitoring treatment response,recurrence,and prognosis.In terms of management,surgery,radiofrequency ablation,symptom control with medications,chemotherapy and molecular targeted therapies are all considered as options.Surgery is the mainstay of treatment,but depends on factors including age of the individual,location,stage,grade,functional status,and the heredity of the tumour(sporadic vs inherited).Medical management is helpful to alleviate the symptoms,manage inoperable lesions,suppress postoperative tumour growth,and manage recurrences.Several molecular-targeted therapies are considered second line to somatostatin analogues.This review is a clinical update on the pathophysiological aspects,diagnostic algorithm,and management of GEP NENs.