Laura Rizza

Somatostatin analogs therapy in gastroenteropancreatic neuroendocrine tumors: Current aspects and new perspectives

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare tumors that present many clinical features secreting peptides and neuroamines that cause distinct clinical syndromes such as carcinoid syndrome. However most of them are clinically silent until late presentation with mass effects. Surgical resection is the first line treatment for a patient with a GEP-NET while in metastatic disease multiple therapeutic approaches are possible. GEP-NETs are able to express somatostatin receptors (SSTRs) bounded by somatostatin (SST) or its synthetic analogs, although the subtypes and number of SSTRs expressed are very variable. In particular, SST analogs are used frequently to control hormone-related symptoms while their anti-neoplastic activity seems to result prevalently in tumor stabilization. Patients who fail to respond or cease to respond to standard SST analogs treatment seem to have a response to higher doses of these drugs. For this reason, the use of higher doses of SST analogs will probably improve the clinical management of these patients.

Everolimus is a new anti-cancer molecule: Metabolic side effects as lipid disorders and hyperglycemia

In the last few years, molecular targeted therapies have replaced traditional cytotoxic chemotherapy in the fight against many cancers to the extent that our understanding of tumor biology has become more sophisticated. This shift has markedly changed adverse event profiles, compared to cytotoxic chemotherapy, affecting a diverse range of organ systems. Everolimus was approved by the FDA in 2011 for the treatment of progressive pancreatic NE tumors. It is an inhibitor of mammalian target of rapamycin (mTOR) and exhibits antitumor activity via disruption of various signaling pathways and its used in the treatment of advanced renal cell cancer, breast cancer and neuroendocrine tumors (NET); its used also as anti-rejection agent for transplantation but with lower doses for anti-rejection (1.5-3.0 mg/day) than for anti-cancer (5-10 mg/day) treatment. Metabolic side effects are the most frequent reported and will be discussed in this review.

Chromogranin A: From Laboratory to Clinical Aspects of Patients with Neuroendocrine Tumors

Background. Neuroendocrine tumors (NETs) are characterized by having behavior and prognosis that depend upon tumor histology, primary site, staging, and proliferative index. The symptoms associated with carcinoid syndrome and vasoactive intestinal peptide tumors are treated with octreotide acetate. The PROMID trial assesses the effect of octreotide LAR on the tumor growth in patients with well-differentiated metastatic midgut NETs. The CLARINET trial evaluates the effects of lanreotide in patients with nonfunctional, well-, or moderately differentiated metastatic enteropancreatic NETs. Everolimus has been approved for the treatment of advanced pancreatic NETs (pNETs) based on positive PFS effects, obtained in the treated group. Sunitinib is approved for the treatment of patients with progressive gastrointestinal stromal tumor or intolerance to imatinib, because a randomized study demonstrated that it improves PFS and overall survival in patients with advanced well-differentiated pNETs. In a phase II trial, pasireotide shows efficacy and tolerability in the treatment of patients with advanced NETs, whose symptoms of carcinoid syndrome were resistant to octreotide LAR. An open-label, phase II trial assesses the clinical activity of long-acting repeatable pasireotide in treatment-naive patients with metastatic grade 1 or 2 NETs. Even if the growth of the neoplasm was significantly inhibited, it is still unclear whether its antiproliferative action is greater than that of octreotide and lanreotide. Because new therapeutic options are needed to counter the natural behavior of neuroendocrine tumors, it would also be useful to have a biochemical marker that can be addressed better in the management of these patients. Chromogranin A is currently the most useful biomarker to establish diagnosis and has some utility in predicting disease recurrence, outcome, and efficacy of therapy.

Indirect basal metabolism estimation in tailoring recombinant human TSH administration in patients affected by differentiated thyroid cancer: A hypothesis-generating study

Purpose Recombinant human TSH (rhTSH) is currently used in follow-up of patients affected by differentiated thyroid cancer (DTC). Age, sex, weight, body mass index, body surface area (BSA) and renal function are known factors affecting serum TSH peak levels, but the proper rhTSH dose to deliver to single patient remains elusive. In this study, the correlations of basal metabolic rates with serum TSH peak following rhTSH administration were investigated. Methods We evaluated 221 patients affected by thyroid cancer that received a standard dose rhTSH. Blood samples were collected at pre-established time points. Data on body weight, height, and BSA were collected. The Mifflin-St Jeor and Fleisch equations were used to assess basal metabolism. Results The median value (range) of serum TSH peaks was 142 ± 53 μU/ml. Serum TSH peaks were significantly lower in males than in females (p = 0.04). TSH values also increased with age. Data showed a significant decrease of TSH peak levels at day 3 from the administration of rhTSH when basal metabolic rates increased (p = 0.002 and p = 0.009, respectively). Similar findings were observed at day 5 (p = 0.004 and p = 0.04, respectively). A multivariate analysis of several factors revealed that patients’ basal metabolism (obtained using the Mifflin-St Jeor but not Fleisch equation) predicts serum TSH level peak at day 3 (p < 0.001). These results were used to generate a new formula based on Mifflin-StJeor equation which reveals as a promising tool in tailoring rhTSH dose. Conclusion Basal metabolism appears an improving factor in tailoring diagnostic rhTSH dose in patients affected by DTC.

CARDIOVASCULAR FEATURES OF POSSIBLE AUTONOMOUS CORTISOL SECRETION IN PATIENTS WITH ADRENAL INCIDENTALOMAS

BACKGROUND Low-grade incomplete post-dexamethasone cortisol suppression in patients with adrenal incidentalomas - recently defined as possible autonomous cortisol secretion (pACS) - has been associated with increased cardiovascular events and mortality. However, prospective studies documenting cardiac abnormalities in these patients are lacking. SUBJECTS AND METHODS Between July 2016 and September 2017, 71 consecutive patients with adrenal lesions were prospectively screened for hypercortisolism by dexamethasone suppression test (NCT 02611258). Complete anthropometric, metabolic and hormonal parameters were recorded along with full cardiac ultrasound assessment and noninvasive measurement of arterial stiffness. All patients underwent chemical-shift magnetic resonance imaging to characterize the lesions. Cardiovascular outcomes were recorded in blind. RESULTS According to post-dexamethasone suppression cortisol values (post-DST), 34 patients had pACS and 37 non-functioning adenomas (NFA). The two groups were similar in sex, BMI, age distribution, cardiovascular risk factors and comorbidities. Left ventricular mass index (LVMIBSA) was increased in pACS compared to NFA (P = 0.006) and mildly correlated to the post-DST cortisol level (rho = 0.347; P = 0.004). The post-DST cortisol levels explained up to 13.7% of LVMIBSA variance (P = 0.002). Compared to NFA, patients with pACS had a higher prevalence of diastolic dysfunction (35.1% vs 82.6%; P = 0.001) and worse arterial stiffness assessed by pulse wave velocity (P = 0.033). CONCLUSIONS In apparently asymptomatic patients, mild autonomous cortisol secretion can sustain early cardiac and vascular remodeling, independently of other risk factors. The morphological and functional cardiovascular changes observed in pACS underline the need for further studies to correctly define the long-term management of this relatively common condition.