Exocrine pancreatic insufficiency and somatostatin analogs in patients with neuroendocrine neoplasia

Sarcopenia in Patients with Advanced Gastrointestinal Well-Differentiated Neuroendocrine Tumors

BACKGROUND

Neuroendocrine neoplasms (NENs) are slow-growing tumors. Sarcopenia is defined as the loss of muscle mass, strength, and physical performance. First-line NEN therapy is somatostatin analogs, which could be responsible for malabsorption conditions, such as pancreatic exocrine insufficiency (EPI) with underlying sarcopenia.

AIM

Evaluate the prevalence of sarcopenia in patients with NENs at diagnosis and during follow-up.

METHODS

A retrospective single-center study was conducted, including patients with advanced intestinal NENs G1/G2 (excluded pancreatic NENs). CT scans were analyzed at diagnosis and after 6 months of therapy, and the skeletal muscle index was assessed.

RESULTS

A total of 30 patients (F:M = 6:24) were enrolled, with the following primary tumor sites: 25 in the ileum, 1 stomach, 2 jejunum, and 2 duodenum. At diagnosis, 20 patients (66.6%) showed sarcopenic SMI values, and 10 patients (33.3%) showed non-sarcopenic SMI values. At follow-up, three more patients developed sarcopenic SMI values. Statistical significance in relation to the presence of sarcopenia was found in the group of patients with carcinoid syndrome (p = 0.0178), EPI (p = 0.0018), and weight loss (p = 0.0001).

CONCLUSION

Sarcopenia was present in 2/3 of the patients with advanced intestinal NENs at the diagnosis and during the follow-up. It is reasonable to consider this condition to improve clinical outcomes.

Gastrointestinal side effects of somatostatin analogs in neuroendocrine tumors: a focused review

Neuroendocrine tumors (NETs) are a group of well-differentiated heterogeneous neoplasms characterized by slow progression and distinct clinical and biological behavior. In the majority of patients with NET, first-line treatment is represented by somatostatin analogs (SSAs) that, despite being drugs with high tolerability (even at high doses) and providing to carcinoid symptoms control and anti-proliferative effects, may present some side effects, with potential impact on quality of life and nutritional status. The most frequent side effects are represented by gastrointestinal events in particular alterations in bowel habits (diarrhea and constipation), abdominal pain, exocrine pancreatic insufficiency, and cholelithiasis. Considering the relative rarity of NETs, literature about frequency and standard clinical management of adverse events SSA-related is still lacking and heterogeneous. The aim of this review is to arm gastroenterologists and other physicians treating NET patients with essential knowledge on the side effects of SSAs. By identifying and managing these adverse events early, healthcare professionals can offer optimal care, avert foreseeable complications, and ensure the best outcomes for patients. Without such early recognition, there is a risk of diminishing the patient's quality of life and their ability to sustain treatment over time.

Long-acting somatostatin analogs and well differentiated neuroendocrine tumors: a 20-year-old story

PURPOSE

The specific indications of somatostatin analogs (SSAs) in patients with neuroendocrine tumor (NET) emerged over the time. The objective of this review is to summarize and discuss the most relevant data concerning long-acting SSAs in NET.

METHODS

A narrative review was performed including publications focusing on therapy with the long-acting octreotide, lanreotide, and pasireotide in patients with NET.

RESULTS

Long-acting SSAs confirm to be a manageable and widely used tool in patients with NET. Both long-acting octreotide and lanreotide are safe as the short-acting formulations, while patient compliance and adherence is further improved. Together with some randomized phase-3 trials, many retrospective and prospective studies have been performed in the last 20 years revealing a variable but substantial impact on progression free survival, not only in gastroenteropancreatic but also in lung and unknown primary NETs. The most frequent tumor response to SSAs is stable disease, but an objective response can be observed, more frequently by using high-dose schedules and in MEN1-related pancreatic NETs. Low tumor burden, low tumor grade (G1 and low G2), good performance status and use as first-line therapy are the main predictive factors to SSAs in NET patients. Pasireotide has been evaluated in few studies. This compound remains a promising SSA and would deserve to be further evaluated as a potential additional indication in NET therapy.

CONCLUSIONS

Long-acting SSAs are an effective and safe initial therapy of patients with well differentiated NET, allowing tumor growth as well as symptoms control for long-time in selected patients.

Management of Functional Pancreatic Neuroendocrine Neoplasms

OPINION STATEMENT

Functional pancreatic neuroendocrine neoplasms (pNENs) are rare and heterogeneous diseases in terms of both clinical and pathological aspects. These tumors secrete hormones or peptides, which may cause a wide variety of symptoms related to a clinical syndrome. The management of functional pNENs is still challenging for clinicians due to the need to control both tumor growth and specific symptoms. Surgery remains the cornerstone in the management of local disease because it can definitively cure the patient. However, when the disease is not resectable, a broad spectrum of therapeutic options, including locoregional therapy, somatostatin analogs (SSAs), targeted therapies, peptide-receptor radionuclide therapy (PRRT), and chemotherapy, are available. The present review summarizes the main key issues regarding the clinical management of these tumors, providing a specific highlight on their therapeutic approach.

Targeting neuroendocrine tumors with octreotide and lanreotide: Key points for clinical practice from NET specialists

Octreotide and lanreotide are the two somatostatin analogs (SSA) currently available in clinical practice. They have been approved first to control the clinical syndrome (mainly carcinoid syndrome) associated with functioning neuroendocrine tumors (NET) and later for tumor growth control in advanced low/intermediate grade NET. Although evidence regarding their role, especially as antiproliferative therapy, has been increasing over the years some clinical indications remain controversial. Solicited by AIOM (Italian Association of Medical Oncology) a group of clinicians from various specialties, including medical oncology, endocrinology, and gastroenterology, deeply involved in NET for their clinical and research activity, addressed eight open questions, critically reviewing evidence and guidelines and sharing clinical take-home messages. The questions regarded the use of long-acting octreotide and lanreotide in the following settings: functioning and non-functioning NET refractory to label dose, first-line metastatic pulmonary NET, combination with other therapy with an antiproliferative intent, maintenance in NET responding to other therapies, adjuvant treatment, Ki-67-related cut-off, somatostatin receptor imaging, safety, and feasibility. The level of evidence is not absolute for the majority of these clinical contexts, so it is recommended to distinguish routine versus sporadic utilization in very selected cases. Mention of such specific issues by the main European guidelines (ENETS, European Neuroendocrine Tumor Society, and ESMO, European Society for Medical Oncology) was explored and their position reported. However, different clinical decisions on single patients could be made if the case is carefully discussed within a NET-dedicated multidisciplinary team.

Casting a Wider NET: Pancreatic Exocrine Insufficiency Induced by Somatostatin Analogues among Patients with Neuroendocrine Tumours?

Somatostatin-analogues (SSAs) are a first-line treatment of unresectable neuroendocrine tumours (NETs). However, SSAs inhibit pancreatic secretions, which could lead to pancreatic exocrine insufficiency (PEI). PEI is known to be detrimental to patient quality of life and nutritional status. This study aimed to evaluate the effect of SSAs on pancreatic exocrine function in patients with NETs, using the ¹³C-mixed triglyceride breath test (¹³C-MTGT). Exocrine function was assessed using the ¹³C-MTGT at baseline and after a third SSA injection (two months). A quotient of ¹³CO₂/¹²CO₂ was measured by mass spectrometry, and the cumulative percent dose recovered at 6 h (cPDR) is reported. The secondary endpoints investigated were change in weight, HbA1C, and vitamin D levels. Ten patients completed the study. Exocrine function reduced in all patients (n = 10) following SSA therapy (median reduction from baseline: -23.4% (range: -42.1-0.5%, p = 0.005)). vitamin D levels decreased in all but one patient (median decrease from baseline: -26.5%, (-44.7-10%; p = 0.038)), and median HbA1C levels increased by 8.0% (0-59.3%; p = 0.008). Change in weight was not significant (median decrease from baseline: -0.21% (-4.5-3.5%, p = 1.000)). SSA therapy has a consistent impact on exocrine function from early in the treatment course, but the long-term clinical effects of this remain to be defined. Further studies are required to determine the clinical relevance of this observation and optimise the management of PEI in this cohort.

The effects of somatostatin analogues on glycaemia in the treatment of neuroendocrine tumours

Long-acting somatostatin analogues (SSAs) are the most commonly used drugs in the management of neuroendocrine tumours (NETs) because of their ability to control symptoms and prolong survival. SSA use is associated with changes in glucose metabolism. However, the impacts on glycaemic control and body mass index (BMI) caused by SSAs in NETs are largely unknown. In the present study, we evaluated the effects of SSA treatment on BMI and glycated haemoglobin (HbA1c) in our cohort of patients with NETs. We also assessed changes in glycaemic control and BMI before and after SSA treatment. In addition, we assessed the incidence of new diabetes or whether there was worsening of glycaemic control for patients with pre-existing diabetes. The study comprised a retrospective study of 279 patients with NETs who were treated with SSAs between January 2014 and January 2019. Glycaemic control was assessed by measuring changes in Hba1c. A number needed to harm analysis was used to look at new cases of diabetes within the study population. Treatment with SSAs was associated with a mean increase in HbA1c of 3.35 ± 6.30 mmol mol^-1 despite a mean decrease in BMI of -1.04 ± 2.79 kg m^-2 . There were 19 new cases of type 2 diabetes mellitus (T2DM) in the population of 209 with a number needed to harm of 12.5. Of the 34 patients with pre-existing T2DM, five had worsening of their mean HbA1c. Treatment with SSAs for NETs is associated with an increase in HbA1c, despite a reduction in BMI and, importantly, a risk of developing T2DM with a number needed to harm of 12.5. This project was registered with the National Health Service Clinical Audit and Registries. It has a CARMS number - 17666.

What Gastroenterologists Should Know about Carcinoid Syndrome

Carcinoid syndrome (CS) is the most common functional syndrome associated with neuroendocrine neoplasia (NEN), particularly in intestinal NEN with extensive liver metastases. Owing to the heterogenous symptomatic scenario present in CS, recognition of these patients may be challenging. In this review, we explore some key clinical factors used to identify patients affected by CS, with particular focus on differential diagnoses of diarrhea, which is the main symptom of CS. Moreover, we highlight the importance of nutritional screening as a clinical indication to prevent malnutrition and to manage the most common nutrient deficiencies present in these patients.