Advanced Neuroendocrine Tumors Research Articles

Progress in immunotherapy for neuroendocrine neoplasm of the digestive system.

Neuroendocrine neoplasms (NENs) are rare heterogeneous tumors that can develop in almost any organ, with the digestive organs, including the gastrointestinal tract and pancreas being the most commonly affected sites. Despite the fact that advances in initial therapies have progressed, there is presently no recognized effective treatment for advanced NEN. Immune checkpoint inhibitors (ICIs) have shown superior efficacy in treating several types of solid tumors. Despite their successful role in the treatment of partial NENs, such as small cell lung cancer, and Merkel cell carcinoma, the role of ICIs in most of the NENs remains limited. Nevertheless, due to their specific anti-tumor mechanisms and acceptable safety profile, ICIs are a promising avenue for further study in NENs therapy. Recent clinical trials have illustrated that combination therapy with ICI is more efficient than monotherapy, and multiple clinical trials are constantly ongoing to evaluate the efficacy and safety of these combination therapies. Therefore, the purpose of this review is to provide a comprehensive summary of the clinical progress of immunotherapy in NENs affecting the digestive system, with a specific emphasis on the application of programmed cell death protein 1/programmed death receptor ligand 1 inhibitor. Furthermore, this review has an exploration of the potential beneficiary population and the inherent value of utilizing immunotherapy in the management of NENs.

Non-invasive estimation of split renal function from routine 68Ga-SSR-PET/CT scans.

Patients with impaired kidney function are at elevated risk for nephrotoxicity and hematotoxicity from peptide receptor radionuclide therapy (PPRT) for advanced neuroendocrine tumors. Somatostatin receptor (SSR)-PET/CT imaging is the method of choice to identify sufficient SSR expression as a prerequisite for PRRT. Therefore, our study aimed to explore whether split renal function could be evaluated using imaging data from routine SSR-PET/CT prior to PRRT. In total, 25 consecutive patients who underwent SSR-PET/CT (Siemens Biograph mCT®) before PRRT between June 2019 and December 2020 were enrolled in this retrospective study. PET acquisition in the caudocranial direction started at 20 ± 0.5 min after an i.v. injection of 173 ± 20 MBq [68Ga]Ga-ha DOTATATE, and the kidneys were scanned at 32 ± 0.5 min p.i. The renal parenchyma was segmented semi-automatically using an SUV-based isocontour (SUV between 5 and 15). Multiple parameters including SUVmean of renal parenchyma and blood pool, as well as parenchyma volume, were extracted, and accumulation index (ACI: renal parenchyma volume/SUVmean) and total kidney accumulation (TKA: SUVmean x renal parenchyma volume) were calculated. All data were correlated with the reference standard tubular extraction rate (TER-MAG) from [99mTc]Tc-MAG3 scintigraphy and glomerular filtration rate (GFRCDK - EPI). SUVmean of the parenchymal tracer retention showed a negative correlation with TERMAG (r: -0.519, p < 0.001) and GFRCDK - EPI (r: -0.555, p < 0.001) at 32 min p.i. The herein-introduced ACI revealed a significant correlation (p < 0.05) with the total tubular function (r: 0.482), glomerular renal function (r: 0.461), split renal function (r: 0.916), and absolute single-sided renal function (r: 0.549). The mean difference between the split renal function determined by renal scintigraphy and ACI was 1.8 ± 4.2 % points. This pilot study indicates that static [68Ga]Ga-ha DOTATATE PET-scans at 32 min p.i. may be used to estimate both split renal function and absolute renal function using the herein proposed "Accumulation Index" (ACI).

CVM-1118: A potent oral anti-vasculogenic mimicry (VM) agent in patients with advanced neuroendocrine tumors (NETs)—A phase IIa study.

e16235 Background: CVM-1118 is a potent anti-tumor new chemical entity with multiple mechanisms of action including induction of apoptosis, cell cycle arrest, and inhibition of VM network formation. The Phase I trial in Asia determined an MTD of 600 mg daily (300 mg BID) with a favorable safety profile. The best response was stable disease with measurable tumor reduction in one patient with NET. We present preliminary results for this ongoing Phase IIa study. Methods: Eligible patients had advanced NETs (low/intermediate grade lung or WHO grade 1 or 2 gastrointestinal or pancreatic origin) which were refractory to standard of care therapy and progressed within 6 months prior to screening. Patients received oral CVM-1118 at 200 to 300 mg BID (400 to 600 mg daily) in 28-day cycles. Pharmacokinetics (PK) was assessed. The primary endpoint was progression-free survival (PFS) and secondary endpoints were objective response rate (ORR), disease control rate (DCR), duration of overall response (DoR), time-to-progression (TTP), and overall survival (OS). Planned enrollment is 33 evaluable patients. Results: As of February 10, 2023, 30 patients were enrolled, of which 21 evaluable patients (12 M/9 F; median age 61 y, range 37–82 y) were predominately grade 2 pNET (12/21, 57%) or GI NET (8/21, 38%). The majority (14/21, 67%) had disease progression after prior treatment with chemotherapy or small molecule inhibitor (median of 1 prior therapy). The duration of CVM-1118 treatment ranged from 1.4–34.6 mos (median 3.8 mos) with 4/21 (19%) patients remaining on treatment for more than 20 mos (range 22–34 mos). The median PFS was 6.9 mos (95% CI 3.3–10.3 mos), which exceeded the historical estimate for PFS of 4–6 mos (Raymond et al., 2011; Yao et al., 2016). The 8-mo and 12-mo PFS rates were 42% (95% CI 25–64%) and 29% (95% CI 14–50%), respectively. The DCR was 66.7% (95% CI 45–83%) with an ORR of 4.8% (1 PR with ongoing tumor reduction of 46% in pNET group). The most common treatment-related AEs ≥ grade 3 included ALT/AST increased (3.3%), diarrhea (3.3%), anemia (3.3%), neutrophil count decreased (3.3%), and tumor lysis syndrome (3.3%). No CVM-1118-related SAEs were reported. PK results showed CVM-1118 was rapidly metabolized to the active metabolite CVM-1125 in all patients following oral dosing. On Day 1, the mean drug exposure of CVM-1125 was Cmax 418 ng/mL and AUC0-24 2170 ng·hr/mL. Intersubject variability of drug exposure appeared to be high; the T1/2 of CVM-1125 was ~2.2 hr. No clear correlation between drug exposure and adverse effects or tumor reduction was observed. Conclusions: CVM-1118 has demonstrated a durable DCR with acceptable safety and tolerability. PK results showed good drug exposure with T1/2 of CVM-1125 ~2.2 hr. These data support future studies in patients with advanced NETs. Raymond E et al., 2011. N Eng J Med 364(6): 501-513. Yao JC et al., 2016. Lancet 387(10022): 968-977. Clinical trial information: NCT03600233 .

Proposal of early CT morphological criteria for response of liver metastases to systemic treatments in gastroenteropancreatic neuroendocrine tumors: Alternatives to RECIST.

RECIST 1.1 criteria are commonly used with computed tomography (CT) to evaluate the efficacy of systemic treatments in patients with neuroendocrine tumors (NETs) and liver metastases (LMs), but their relevance is questioned in this setting. We aimed to explore alternative criteria using different numbers of measured LMs and thresholds of size and density variation. We retrospectively studied patients with advanced pancreatic or small intestine NETs with LMs, treated with systemic treatment in the first-and/or second-line, without early progression, in 14 European expert centers. We compared time to treatment failure (TTF) between responders and non-responders according to various criteria defined by 0%, 10%, 20% or 30% decrease in the sum of LM size, and/or by 10%, 15% or 20% decrease in LM density, measured on two, three or five LMs, on baseline (≤1 month before treatment initiation) and first revaluation (≤6 months) contrast-enhanced CT scans. Multivariable Cox proportional hazard models were performed to adjust the association between response criteria and TTF on prognostic factors. We included 129 systemic treatments (long-acting somatostatin analogs 41.9%, chemotherapy 26.4%, targeted therapies 31.8%), administered as first-line (53.5%) or second-line therapies (46.5%) in 91 patients. A decrease ≥10% in the size of three LMs was the response criterion that best predicted prolonged TTF, with significance at multivariable analysis (HR 1.90; 95% CI: 1.06-3.40; p = .03). Conversely, response defined by RECIST 1.1 did not predict prolonged TTF (p = .91), and neither did criteria based on changes in LM density. A ≥10% decrease in size of three LMs could be a more clinically relevant criterion than the current 30% threshold utilized by RECIST 1.1 for the evaluation of treatment efficacy in patients with advanced NETs. Its implementation in clinical trials is mandatory for prospective validation. Criteria based on changes in LM density were not predictive of treatment efficacy. CLINICAL TRIAL REGISTRATION: Registered at CNIL-CERB, Assistance publique hopitaux de Paris as "E-NETNET-L-E-CT" July 2018. No number was assigned. Approved by the Medical Ethics Review Board of University Medical Center Groningen.

Differences in outcomes of patients with advanced neuroendocrine tumors treated with chemotherapy versus targeted agents.

e16303 Background: Pancreas NETs are uncommon and very rare cancer accounting for around 7% of the pancreatic cancer sub patient population, 4,200 patients in the US diagnoses yearly of all cancers in the pancreas. There are very few treatment options available for Metastatic Pancreatic Neuroendocrine Tumor patients. The survival rate depends on a variety of factors, including whether the tumor can be removed using surgery and if the cancer has spread to other parts of the body. The 5-year survival rate non-metastatic pancreas NETs is 93% while metastatic pancreas NETs is 24%. Therefore, this study compares the 5-year overall survival rate of metastatic pancreatic NETs ineligible for surgery who have received chemotherapy alone versus who have received targeted therapy. Methods: Patient cohorts were generated in an electronic medical records (EMR) TriNetX Research Network of 89M patient lives. Patients were identified as either receiving a targeted therapy or patients who were targeted therapy naïve receiving chemotherapy. Both cohorts had a diagnosis of pancreatic NETs (ICD-10 C25.4), at least one documentation of a related metastasis, and no history of any pancreatic surgery. The 5 year overall survival (OS) from first exposure to either targeted therapy or chemotherapy was analyzed using measures of association and survival analysis conducted via Kaplan-Meier estimator. Cohort comparisons were with propensity score matching (PSM) to control for demographic, comorbidity, medication, and diagnostic procedure confounders. Results: After matching, each cohort accounted for 389 patients (43% female, mean age at index 62 +/- 13 SD). There was a significant 5-year mortality risk difference (11.054%, p = 0.0020) between the chemotherapy only cohort (215 patients, 55.27%) vs. the targeted therapy cohort (172 patients, 44.216%) after adjusting for potential confounding factors. Additionally, the 5-year OS rate was 24.951% in the chemotherapy only cohort and 37.222% in the targeted therapy cohort. The difference in survival between the groups was statistically significant (log-rank p = 0.0001). Conclusions: In these cohorts of patients with metastatic pancreas NETs without surgical treatment, we found that targeted therapy was associated with a significant improvement in 5-year overall survival compared to standard chemotherapy alone. Our results suggest that targeted therapy should be considered as a first line treatment option for this severe patient population.

Durvalumab plus tremelimumab for the treatment of advanced neuroendocrine neoplasms of gastroenteropancreatic and lung origin

Single immune checkpoint blockade in advanced neuroendocrine neoplasms (NENs) shows limited efficacy; dual checkpoint blockade may improve treatment activity. Dune (NCT03095274) is a non-randomized controlled multicohort phase II clinical trial evaluating durvalumab plus tremelimumab activity and safety in advanced NENs. This study included 123 patients presenting between 2017 and 2019 with typical/atypical lung carcinoids (Cohort 1), G1/2 gastrointestinal (Cohort 2), G1/2 pancreatic (Cohort 3) and G3 gastroenteropancreatic (GEP) (Cohort 4) NENs; who progressed to standard therapies. Patients received 1500 mg durvalumab and 75 mg tremelimumab for up to 13 and 4 cycles (every 4 weeks), respectively. The primary objective was the 9-month clinical benefit rate (CBR) for cohorts 1-3 and 9-month overall survival (OS) rate for Cohort 4. Secondary endpoints included objective response rate, duration of response, progression-free survival according to irRECIST, overall survival, and safety. Correlation of PD-L1 expression with efficacy was exploratory. The 9-month CBR was 25.9%/35.5%/25% for Cohorts 1, 2, and 3 respectively. The 9-month OS rate for Cohort 4 was 36.1%, surpassing the futility threshold. Benefit in Cohort 4 was observed regardless of differentiation and Ki67 levels. PD-L1 combined scores did not correlate with treatment activity. Safety profile was consistent with that of prior studies. In conclusion, durvalumab plus tremelimumab is safe in NENs and shows modest survival benefit in G3 GEP-NENs; with one-third of these patients experiencing a prolonged OS.

Safety and Efficacy of 177 Lu-DOTATATE in Neuroendocrine Tumor Patients With Extensive Bone Disease.

The aim of this study was to assess the efficacy and safety of 177 Lu-DOTATATE in patients with neuroendocrine tumors (NETs) and extensive bone metastases, that is, more than 50% of the skeleton involved. A single-center retrospective analysis was performed in 30 patients (13 women and 17 men, mean age, 60 years; range, 35-77 years) undergoing 177 Lu-DOTATATE therapy. Patients had progressive metastatic NETs with extensive skeletal metastases (>50% skeletal involvement seen on baseline 68 Ga-DOTATATE PET/CT). The average administered activity was 7.308 (SD, 0.02) GBq per cycle with average treatment interval of 15 weeks. Survival analyses (progression-free survival [PFS], overall survival), radiological response assessment, toxicity assessment, and health-related quality of life (QoL) was performed. Overall, 26 patients completed 4 cycles, and 4 patients had less than 4 cycles of 177 Lu-DOTATATE. One patient (3%) did not complete treatment because of hematological toxicity. The estimated median PFS and median overall survival were calculated at 27 and 35 months, respectively. End-of-treatment radiological assessment showed partial response in 5 patients (17%), stable disease in 20 patients (66%), and radiological progressive disease in 3 patients (10%). Clinical progression was seen in a further 2 patients (7%).The incidence of grade 3/4 bone marrow toxicity was 10%. No patient had grade 3/4 peptide receptor radionuclide therapy-related nephrotoxicity. There was overall improvement in global QoL score (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Gastrointestinal NET-21) ( P = 0.019). 177 Lu-DOTATATE seems to have satisfactory therapeutic outcome in patients with advanced metastatic NET with extensive bone disease, with reasonable PFS and significant improvement in the global health-related QoL. The bone marrow toxicity was within the accepted range. Increasing the interval between cycles does not seem to reduce efficacy and may reduce toxicity, ensuring the bone marrow has sufficient time to recover between cycles.

Treatment with 177Lu-dotatate in metastasic advanced neuroendocrine tumors with positive expression of somatostatin receptors, in a third level hospital in Spain from 2015-2022

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Clinical Outcomes of DEB-TACE in Hepatic Metastatic Neuroendocrine Tumors: A 5-Year Single-Institutional Experience

To evaluate single-institution outcomes of drug-eluting bead transarterial chemoembolization (DEB-TACE) in the treatment of locally advanced neuroendocrine tumor (NET) hepatic metastases with a focus on safety and efficacy of treatment. A single-center retrospective cohort study of the outcomes of consecutive patients with NELM who underwent DEB-TACE between 2014 and 2019 was performed. Clinicopathologic characteristics, radiologic response (modified Response Evaluation Criteria in Solid Tumors) at 1-month follow-up, adverse events, progression-free survival (PFS), and overall survival were calculated. Among 287 patients (mean age of 62 years; 39% male: 61% female), disease burden was bilobar (90.2%) with mean largest tumor diameter measuring 4.9±2.8cm. Of these patients, 14.6% had no evidence of tumor in other organs or lymph nodes. Complete response occurred in 60 (20.9%) patients while 133 (46.3%) had partial responses. Major complication occurred in 2.4%. Liver function tests including total bilirubin and AST were overall stable at the 1-month follow-up, with only a small increase in the ALT at +8.9% (p<0.01). Overall survival was 80.1% at 1 year, 49.1% at 3 years, and 12.3% at 5 years with a mean PFS of 14.4±12.5months. Based on this institutional experience, DEB-TACE is an acceptable locoregional therapy choice for hepatic metastases of NET due to its tolerable safety profile and relative efficacy.

Efficacy of [177Lu]Lu-DOTATATE in metastatic neuroendocrine neoplasms of different locations: data from the SEPTRALU study

BackgroundPeptide receptor radionuclide therapy (PRRT) is one of the most promising therapeutic strategies in neuroendocrine neoplasms (NENs). Nevertheless, its role in certain tumor sites remains unclear. This study sought to elucidate the efficacy and safety of [177Lu]Lu-DOTATATE in NENs with different locations and evaluate the effect of the tumor origin, bearing in mind other prognostic variables. Advanced NENs overexpressing somatostatin receptors (SSTRs) on functional imaging, of any grade or location, treated at 24 centers were enrolled. The protocol consisted of four cycles of 177Lu-DOTATATE 7.4 GBq iv every 8 weeks (NCT04949282).ResultsThe sample comprised 522 subjects with pancreatic (35%), midgut (28%), bronchopulmonary (11%), pheochromocytoma/ paraganglioma (PPGL) (6%), other gastroenteropancreatic (GEP) (11%), and other non-gastroenteropancreatic (NGEP) (9%) NENs. The best RECIST 1.1 responses were complete response, 0.7%; partial response, 33.2%; stable disease, 52.1%; and tumor progression, 14%, with activity conditioned by the tumor subtype, but with benefit in all strata. Median progression-free survival (PFS) was 31.3 months (95% CI, 25.7–not reached [NR]) in midgut, 30.6 months (14.4-NR) in PPGL, 24.3 months (18.0-NR) in other GEP, 20.5 months (11.8-NR) in other NGEP, 19.8 months (16.8–28.1) in pancreatic, and 17.6 months (14.4–33.1) in bronchopulmonary NENs. [177Lu]Lu-DOTATATE exhibited scant severe toxicity.ConclusionThis study confirms the efficacy and safety of [177Lu]Lu-DOTATATE in a wide range of SSTR-expressing NENs, regardless of location, with clinical benefit and superimposable survival outcomes between pNENs and other GEP and NGEP tumor subtypes different from midgut NENs.

An Open-Label, Phase 1b/2 study of Surufatinib in Combination with Tislelizumab in Patients with Advanced Neuroendocrine Tumors

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Natural history study and tissue procurement of neuroendocrine neoplasms (NENs).

TPS659 Background: Neuroendocrine neoplasms (NENs) are a rare spectrum of malignant neoplasms originating from neuroendocrine cells, most commonly affecting the gastrointestinal tract, pancreas, and lungs. Tumors may vary from low grade neuroendocrine tumors (NET) to high grade neuroendocrine carcinomas (NEC). The annual occurrence of NENs is increasing worldwide and currently the incidence in the US is about 6 cases per 100,000 people per year. A variety of therapeutic options are available for advanced NENs, however, when to apply a given option, what combination therapeutic approach should be used, how long treatment should be continued is unclear and controversial. Moreover, unlike common cancers, pre-clinical models for NENs are sorely limited. Without robust pre-clinical models our understanding of tumor pathophysiology and novel drug development can be challenging. Methods: A prospective study to evaluate the natural history and sample acquisition of NENs comprehensively and longitudinally. Patients ≥ 18 years old with histological confirmation of NENs, biochemical evidence of NENs, or by imaging studies of NENs are eligible. Participants are invited to NIH for biannual evaluations or as clinically indicated. Patients complete individual medical history, family history, and laboratory assessments including blood, saliva, and tumor for RNA/DNA analysis. A tumor analysis via a 500+ gene panel (Illumina TruSight Oncology 500 Panel) is performed for comprehensive genomic and epigenomic analysis. When feasible, fresh tissue is collected to develop pre-clinical models for drug testing. If clinically indicated, anatomic and functional imaging is performed. We aim to 1) create a repository of biological samples and conduct future investigations to understand the basic biology of NENs with the goal to develop novel treatment approaches, biomarkers of treatment response, and new prognostic and diagnostic models, 2) acquire clinical data so that the overall genomic, proteomic, and metabolomic alternations can be correlated to clinical parameters, 3) establish organoid cultures, cell line models, and xenograft models corresponding to NENs of various grades for drug screening. This protocol will evaluate the natural history of NENs, allow tissue acquisition, and study this heterogenous group of neoplasms with unique tumor biology, and current clinical management to stabilize correlations with clinical outcomes and develop novel therapies. Clinical trial information: NCT05237934 .

Outcomes and survival in patients with advanced intestinal neuroendocrine tumours on home parenteral nutrition, an international multicentre retrospective cohort study

Only limited information is available on the use of home parenteral nutrition (HPN) in patients with advanced neuroendocrine tumours (NETs) causing intestinal failure (IF). This study aims to report the outcomes of the explore the use of HPN in this patient cohort, in the largest case series to date. A retrospective study in the United Kingdom and the Netherlands was performed, using the UK National British Artificial Nutrition Survey (BANS) and local databases in the Netherlands. Data regarding age, sex, NET grading, staging, treatment, HPN characteristics and survival outcomes were collected. Data were collected on 41 patients (n=18 males, 44%) with a median age of 65. Most primary tumours were in the small bowel (n=35, 85%). The NETs were Grade 1 (n=16, 39%), Grade 2 (n=7, 17%), Grade 3 (n=1, 2%). In 28 patients (n=68%) there was stage IV disease with metastases located in the peritoneum, mesentery and or liver. There were two indications for HPN; short bowel syndrome (n=27, 66%) and inoperable malignant bowel obstruction (n=14, 34%). The median period on HPN was 11 months (interquartile range 4-25 months). 11 patients were still alive and receiving HPN treatment after 2 years, and 6 patients after 3 years. Six patients (22%) with short bowel syndrome (SBS) could be weaned from HPN. There was a statistically significant improved survival for patients with short bowel syndrome (median 24 months) compared to inoperable malignant bowel obstruction (median 7 months). The catheter-related bloodstream infection rate was comparable to other HPN patient cohorts at 1.0 per 1000 catheter days. This study shows that HPN can be used safely in patients with NET and IF to increase survival beyond that reasonably expected in the context of either short bowel syndrome or inoperable malignant bowel obstruction. Patients with short bowel syndrome are most likely to benefit. Further prospective studies are necessary to validate survival benefits and to demonstrate the effect of HPN on quality of life.

FOLFOX-bevacizumab chemotherapy in patients with metastatic neuroendocrine tumors.

Neuroendocrine tumors (NETs) are highly vascularized neoplasms. While FOLFOX chemotherapy has shown efficacy in patients with advanced NETs, its combination with antiangiogenics has been scarcely described. Here, we report the efficacy and tolerance of FOLFOX-bevacizumab in this setting. We retrospectively studied all consecutive patients with metastatic NET treated by FOLFOX-bevacizumab in two expert centers from 2013 to 2020. We assessed time to treatment failure (TTF), objective response rate (ORR) and toxicity. We explored factors associated with TTF and ORR using multivariate analyses. We included 57 patients (35.1% female, median age 61.7 years), with pancreatic (66.7%), small-intestine (14%) or lung (7%) NETs. Most patients (57.9%) had extra-hepatic metastases and G3 NETs accounted for 40.3% of cases. Patients received a median of 17 cycles of treatment, including a median of sevencycles of bevacizumab and/or 5-fluorouracile maintenance. Median TTF was 15.5months (95% CI: 9.8-21.2) and was shorter in patients age > 60 years (HR 2.56, 95% CI: 1.16-5.64), p= .020) and >1 previous systemic treatment line (HR 4.15, 95% CI: 1.96-8.78), p< .001). The ORR was 42.9% and was higher in cases of performance status at 0 (OR 5.25, 95% CI: 1.13-24.35), p= .034) and G3 NET (OR 5.39, 95% CI: 1.23-23.52), p= .025). The FOLFOX-bevacizumab combination has promising efficacy in patients with progressive metastatic NETs and notably for G3 NETs, for which optimal treatment as yet remains ill-defined. Hence, it could be a relevant alternative to alkylating-based chemotherapy in this setting and should be further explored prospectively.

Teranostika i precizna medicina u neuroendokrinim tumorima

Introduction. Neuroendocrine tumors (NETs) have increased expression of somatostatin receptors (SSTR), where subtype 2 and 5 are the most common. Overexpression of the SSTR is an outstanding molecular target for inoperable and metastatic NETs that enables a unique approach of targeted diagnosis and treatment. In addition to SSTRs, neuroendocrine tumors also express other receptors that can be suitable targets for visualization by nuclear medicine methods. Aim. This review paper is focused on the most common radiopharmaceuticals and their molecular targets that are used today based on theranostic approach in NETs. Results. In conventional nuclear medicine, the most important diagnostic radiopharmaceuticals are somatostatin analogs (SSA) labeled with 111 In and 99m Tc, however 99m Tc has advantages over 111 In based on better physical characteristics and better performance. In recent years, highly potent theranostic pairs have been created for the imaging and treatment of NETs, which can strongly bind SSTR. Derivatives of 68 Ga-labeled octreotide are recommended for diagnostics and follow-up of NENs. The great advantage of 68 Ga radiopharmaceuticals is that identical compounds can be labeled with therapeutic radionuclides 90 Y and 177 Lu. Conclusion. Peptide receptor radionuclide therapy is a systemic molecular target therapy that has proven to be safe and very effective in controlling the disease and prolonging the survival of patients with advanced and inoperable NETs. With a negligible number of adverse events, this therapy is safe and should be administered to all patients who meet the necessary criterias, primarily overexpression of the somatostatin receptor type 2.

Patient-Defined Goals and Preferences Among Adults With Advanced Neuroendocrine Tumors.

Patient preferences (quantity vs quality of life; present vs future health) have not been investigated in patients with neuroendocrine tumors (NETs). The goal of this cross-sectional study was to evaluate patient values toward treatment goals and competing health outcomes among adults with NETs. Patients with well-differentiated, grade 1 or 2, advanced NETs starting a new systemic therapy completed 4 tools: (1) Health Outcomes Tool, which ranks the importance of 4 outcomes (survival, function/independence, freedom from pain, freedom from symptoms); (2) Attitude Scale, which identifies the extent to which patients agree with statements related to health outcomes; (3) Now versus Later Tool, which ranks the relative importance of quality of life (QoL) now versus 1 and 5 years from now; and (4) Prognosis and Treatment Perceptions Questionnaire, which identifies the amount of information the patient prefers to receive about their disease and treatment, the patient's treatment goal, the patient's perception of the physician's treatment goal, and self-reported health status. We recruited 60 patients with NETs (50.0% aged ≥65 years; 96.7% with stage IV disease). Primary tumor locations included the gastrointestinal tract (41.7%), pancreas (30.0%), and lung (21.7%). A plurality of patients reported maintaining independence as their most important health outcome (46.7%), followed by survival (30.0%), freedom from pain (11.7%), and freedom from symptoms (11.7%). A total of 67% of patients agreed with the statement, "I would rather live a shorter life than lose my ability to take care of myself"; 85.0% agreed with the statement, "It is more important to me to maintain my thinking ability than to live as long as possible." When asked to choose between current QoL versus QoL 1 year or 5 years in the future as more important, 48.3% and 40.0% of patients valued their QoL 1 year and 5 years in the future, respectively, more than their current QoL. Only 51.7% of patients believed their physician's treatment goals aligned with their own. Adult patients with NETs strongly value independence over survival. More communication between patients with NETs and their physicians is needed to ensure that patient preferences are incorporated into treatment plans.

Capecitabine and Temozolomide (CAPTEM) in Advanced Neuroendocrine Neoplasms (NENs): A Systematic Review and Pooled Analysis.

Retrospective studies and single center experiences suggest a role of capecitabine combined with temozolomide (CAPTEM) in neuroendocrine tumors (NENs). We performed a systematic review to assess the efficacy and safety of CAPTEM in patients affected with NENs, with the aim to better clarify the role of this regimen in the therapeutic algorithm of NENs. A total of 42 articles and 1818 patients were included in our review. The overalldisease control rate was 77% (range 43.5%-100%). The median progression free survival ranged from 4 to 38.5 months, while the median overall survival ranged from 8 to 103 months. Safety analysis showed an occurrence of G3-G4 toxicities in 16.4% of the entire population. The most common toxicities were hematological (27.2%), gastrointestinal (8.3%,) and cutaneous (3.2%). This systematic review demonstratedthat CAPTEM was an effective and relatively safe treatment for patients with advanced well-moderate differentiated NENs of gastroenteropancreatic, lung and unknown origin.

Single centre retrospective review of outcome of 177 Lu-DOTATATE peptide receptor radionuclide therapy in the treatment of progressive metastatic neuroendocrine tumours: Survival, toxicity, and prognostic factors.

The aim of this study was to evaluate the efficacy and safety of 177 Lu-DOTATATE therapy in advanced metastatic disease. A retrospective analysis of 395 patients (180 female, 215 males, mean age 62) with progressive metastatic neuroendocrine tumours (NETs) who were treated with 177 Lu-DOTATATE was performed. Overall, 115 patients had less than four cycles and 280 completed four cycles of treatment. Progression-free survival (PFS) and overall survival (OS) was performed using Kaplan-Meier analysis. Analysis of survival predictors was performed using Cox regression model. Toxicity was defined using the Common Terminology Criteria for Adverse Events version 5 (CTCAE 5.0). The percentage of patients with liver and skeletal metastases were 91 and 57%, respectively. Median PFS and OS were calculated at 33 months (95% CI: 29-37 months) and 46 months (95% CI: 48-56 months), respectively. End of treatment response assessment was performed using cross sectional imaging demonstrated partial response in 22%, stable disease in 64% and progressive disease in 14% of patients. Overall, grade 3 and 4 bone marrow toxicity was seen in 8%. One patient (0.3%) developed irreversible grade 4 nephrotoxicity. Myelodysplastic disease was recorded in one patient (0.3%). Univariate analysis of PFS predictors showed that body mass index (BMI), baseline chromogranin A (CgA) >400 ng/l, baseline alkaline phosphatase (ALP) >130 mg/dl, liver tumour volume and overall tumour burden were significant. On multivariate analysis only Ki67, high CgA and low BMI retained significance. 177 Lu-DOTATATE is an effective treatment in advanced NETs with generally high-volume metastases. It is well-tolerated. Ki-67, CgA and BMI appear to be predictors for PFS.

Evaluation of survival outcomes in patients with sporadic, advanced, unresectable well-differentiated pancreatic neuroendocrine tumors treated initially with octreotide LAR and subsequent therapeutical approaches on relapse. A real-world data set

Introduction. Somatostatin analogs (SSA) are widely used in the treatment of patients with well-differentiated neuroendocrine tumors (NET). There are limited reports about the role of octreotide LAR in first-line therapy of advanced pancreatic NET (pan-NET). This study aimed to evaluate the antiproliferative effect of octreotide LAR in patients with sporadic, advanced, unresectable pan-NET, based on progression-free survival (PFS). Material and methods. This was a retrospective analysis of 374 patients with pan-NET; 41 treated subjects were included. The primary endpoint was PFS defined as the time to disease progression (Response Evaluation Criteria in Solid Tumors: RECIST). Univariate and multivariate analyses were used to identify predictors of PFS. Secondary endpoints included overall survival (OS) and second-line therapies after progression. Results. There were 13 (32%) patients with G1 pan-NET and 28 (68%) with pan-NET G2, 21 female and 20 male, with mean age 55.4 (range 29–87). Median PFS was 9.0 months (95% CI 4.7–24.0). Subgroup analysis revealed that G1 and no-bulky liver disease ( &lt; 25% liver volume) were associated with significantly longer PFS. Univariate analysis confirmed a correlation between G1 [0.34 hazard rate (HR) of progression or death (95% CI 0.16–0.72)] and no-bulky liver disease HR = 0.31 (95% CI 0.13–0.71). Multivariable analysis demonstrated that only functional (secretory) pan-NET was associated as an independent factor with shorter PFS HR = 2.97 (95% CI 1.0–8.74). Median OS was 105.4 months (95% CI 40.0–172.0). After relapse following initial systemic therapy, the second line was used in 34 subjects, 3rd line in 18th, and 4th line in 9 subjects. Conclusions. Octreotide LAR shows moderate antiproliferative activity in pan-NET. Prolonged PFS may be associated with G1 and low-volume metastatic liver disease. In patients with progressive disease, various treatment options were used, which resulted in median OS of 105.4 months.

Treatment Sequencing Strategies in Advanced Neuroendocrine Tumors: A Review.

Neuroendocrine tumor (NET) incidence has grown. The treatment landscape for advanced NETs is rapidly evolving, but there are limited head-to-head data to guide treatment sequencing decisions. We assessed the available clinical data to aid practicing clinicians in their routine clinical decision-making. Clinical trials have demonstrated efficacy benefits for new therapies in advanced NETs. Emerging long-term data from these trials have enabled clinicians to make more accurate risk-benefit assessments, particularly for patients receiving multiple lines of therapy. However, clinical data specifically regarding treatment sequencing are limited. In lieu of definitive data, treatment sequencing should be based on disease-related factors (e.g., site of tumor origin, volume of disease) and patient-related characteristics (e.g., comorbidities, patient preferences). Clinical decision-making in advanced NETs remains highly individualized and complex; important evidence gaps regarding treatment sequencing remain. Given this, advanced NET management should be a joint effort of multidisciplinary teams at referring and high-volume centers. Additional clinical trial and real-world evidence are needed to meet the challenge of understanding how to sequence available NET therapies. Until these trials are conducted, the best practices provided in this review may serve as a guide for clinicians making treatment sequencing decisions based on the available data.