Non-invasive imaging of sympathetic innervation of the pancreas in individuals with type 2 diabetes.

AIMS/HYPOTHESIS: Compromised pancreatic sympathetic innervation has been suggested as a factor involved in both immune-mediated beta cell destruction and endocrine dysregulation of pancreatic islets. To further explore these intriguing findings, new techniques for in vivo assessment of pancreatic innervation are required. This is a retrospective study that aimed to investigate whether the noradrenaline (norepinephrine) analogue 11C-hydroxy ephedrine (11C-HED) could be used for quantitative positron emission tomography (PET) imaging of the sympathetic innervation of the human pancreas. METHODS: In 25 individuals with type 2 diabetes and 64 individuals without diabetes, all of whom had previously undergone 11C-HED-PET/CT because of pheochromocytoma or paraganglioma (or suspicion thereof), the 11C-HED standardised uptake value (SUVmean), 11C-HED specific binding index (SBI), pancreatic functional volume (FV, in ml), functional neuronal volume (FNV, calculated as SUVmean × FV), specific binding index with functional volume (SBI FV, calculated as SBI × FV) and attenuation on CT (HU) were investigated in the entire pancreas, and additionally in six separate anatomical pancreatic regions. RESULTS: Generally, 11C-HED uptake in the pancreas was high, with marked individual variation, suggesting variability in sympathetic innervation. Moreover, pancreatic CT attenuation (HU) (p<0.001), 11C-HED SBI (p=0.0049) and SBI FV (p=0.0142) were lower in individuals with type 2 diabetes than in individuals without diabetes, whereas 11C-HED SUVmean (p=0.15), FV (p=0.73) and FNV (p=0.30) were similar. CONCLUSIONS/INTERPRETATION: We demonstrate the feasibility of using 11C-HED-PET for non-invasive assessment of pancreatic sympathetic innervation in humans. These findings warrant further prospective evaluation, especially in individuals with theoretical defects in pancreatic sympathetic innervation, such as those with type 1 diabetes.

First-in-human evaluation of [18F]CETO: a novel tracer for adrenocortical tumours.

PURPOSE: [11C]Metomidate positron emission tomography (PET) is currently used for staging of adrenocortical carcinoma and for lateralization in primary aldosteronism (PA). Due to the short half-life of carbon-11 and a high non-specific liver uptake of [11C]metomidate there is a need for improved adrenal imaging methods. In a previous pre-clinical study para-chloro-2-[18F]fluoroethyletomidate has been proven to be a specific adrenal tracer. The objective is to perform a first evaluation of para-chloro-2-[18F]fluoroethyletomidate positron emission computed tomography ([18F]CETO-PET/CT) in patients with adrenal tumours and healthy volunteers. METHODS: Fifteen patients underwent [18F]CETO-PET/CT. Five healthy volunteers were recruited for test-retest analysis and three out of the five underwent additional [15O]water PET/CT to measure adrenal blood flow. Arterial blood sampling and tracer metabolite analysis was performed. The kinetics of [18F]CETO were assessed and simplified quantitative methods were validated by comparison to outcome measures of tracer kinetic analysis. RESULTS: Uptake of [18F]CETO was low in the liver and high in adrenals. Initial metabolization was rapid, followed by a plateau. The kinetics of [18F]CETO in healthy adrenals and all adrenal pathologies, except for adrenocortical carcinoma, were best described by an irreversible single-tissue compartment model. Standardized uptake values (SUV) correlated well with the uptake rate constant K1. Both K1 and SUV were highly correlated to adrenal blood flow in healthy controls. Repeatability coefficients of K1, SUV65-70, and SUV120 were 25, 22, and 17%. CONCLUSIONS: High adrenal uptake combined with a low unspecific liver uptake suggests that 18F]CETO is a suitable tracer for adrenal imaging. Adrenal SUV, based on a whole-body scan at 1 h p.i., correlated well with the net uptake rate Ki. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05361083 Retrospectively registered 29 April 2022. at,  https://clinicaltrials.gov/ct2/show/NCT05361083.

Overall Survival in Patients with Stage IV Pan-NET Eligible for Liver Transplantation.

BACKGROUND: The use of liver transplantation (LT) in patients with stage IV neuroendocrine pancreatic tumors (pan-NET) is under debate. Previous studies report a 5-year survival of 27-53% after LT in pan-NET and up to 92.7% in patients with mixed NETs. This study aimed to determine survival rates of patients with stage IV pan-NET meeting criteria for LT while only subjected to multimodal treatment. METHODS: Medical records of patients with pan-NET diagnosed from 2000 to 2021 at a tertiary referral center were evaluated for eligibility. Patients without liver metastases, who did not undergo primary tumor surgery, age > 75 years and with grade 3 tumors were excluded. The patients were divided into groups; all included patients, patients meeting the Milan, the United Network for Organ Sharing (UNOS) or the European Neuroendocrine Tumor Society (ENETS) criteria for LT. Kaplan-Meier survival analysis was used to calculate overall survival. RESULTS: Out of 519 patients with pan-NET, 41 patients were included. Mean follow-up time was 5.4 years. Overall survival was 9.3 years (95% Cl 6.8-11.7), and 5-year survival was 64.7% (95% CI 48.2-81.2). Patients meeting the Milan, ENETS and UNOS criteria for LT had a 5-year survival of 64.9% (95% CI 32.2-97.6), 85.7% (95% CI 59.8-100.0) and 55.4% (95% CI 26.0-84.8), respectively. CONCLUSIONS: In patients with stage IV pan-NET, grade 1 and 2, with no extra abdominal disease, 5-year survival was 64.7% (95% CI 48.2-81.2). As these survival rates exceed previously published series of LT for pan-NET, the evidence base for this treatment is very weak.

Para-chloro-2-[18F]fluoroethyl-etomidate: A promising new PET radiotracer for adrenocortical imaging.

Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed as a positron emission tomography (PET) radiotracer for adrenocortical tumours and has also been suggested for imaging in primary aldosteronism (PA). A disadvantage of [11C]MTO is the rather high non-specific binding in the liver, which impacts both visualization and quantification of the uptake in the right adrenal gland. Furthermore, the short 20-minute half-life of carbon-11 is a logistic challenge in the clinical setting. Objectives: The aim of this study was to further evaluate the previously published fluorine-18 (T1/2=109.5 min) etomidate analogue, para-chloro-2-[18F]fluoroethyl etomidate; [18F]CETO, as an adrenal PET tracer. Methods: In vitro experiments included autoradiography on human and cynomolgus monkey (non-human primate, NHP) tissues and binding studies on adrenal tissue from NHPs. In vivo studies with [18F]CETO in mice, rats and NHP, using PET and CT/MRI, assessed biodistribution and binding specificity in comparison to [11C]MTO. Results: The binding of [18F]CETO in the normal adrenal cortex, as well as in human adrenocortical adenomas and adrenocortical carcinomas, was shown to be specific, both in vitro (in humans) and in vivo (in rats and NHP) with an in vitro Kd of 0.66 nM. Non-specific uptake of [18F]CETO in NHP liver was found to be low compared to that of [11C]MTO. Conclusions: High specificity of [18F]CETO to the adrenal cortex was demonstrated, with in vivo binding properties qualitatively surpassing those of [11C]MTO. Non-specific binding to the liver was significantly lower than that of [11C]MTO. [18F]CETO is a promising new PET tracer for imaging of adrenocortical disease and should be evaluated further in humans.

Low bone mineral density following gastric bypass is not explained by lifestyle and lack of exercise.

BACKGROUND: Bariatric surgery, Roux-en-Y gastric bypass (RYGBP) in particular, is associated with weight loss as well as low bone mineral density. Bone mineral density relies upon multiple factors, some of which are lifestyle factors. The aim of this study was to compare lifestyle factors in order to eliminate them as culprits of the suspected difference in BMD in RYGBP operated and controls. MATERIALS AND METHODS: Study participants included 71 RYGBP-operated women (42.3 years, BMI 33.1 kg/m2) and 94 controls (32.4 years, BMI 23.9 kg/m2). Each completed a DEXA scan, as well as survey of lifestyle factors (e.g. physical activity in daily life, corticosteroid use, and calcium intake). All study participants were premenopausal Caucasian women living in the same area. Blood samples were taken in RYGBP-patients. RESULTS: BMD was significantly lower in RYGBP, femoral neck 0.98 vs. 1.04 g/cm2 compared to controls, despite higher BMI (present and at 20 years of age) and similar physical activity and calcium intake. In a multivariate analysis, increased time since surgery and age were negatively associated with BMD of the femoral neck and total hip in RYGBP patients. CONCLUSION: Despite similar lifestyle, RYGBP was followed by a lower BMD compared to controls. Thus, the reduced BMD in RYGBP cannot be explained, seemingly nor prevented, by lifestyle factors. As the reduction in BMD was associated with time since surgery, strict follow-up is a lifelong necessity after bariatric surgery, and especially important in younger bariatric patients.

High-Grade Progression Confers Poor Survival in Pancreatic Neuroendocrine Tumors.

INTRODUCTION: Little is known about how pancreatic neuroendocrine tumors (PanNETs) evolve over time and if changes toward a more aggressive biology correlate with prognosis. The purpose of this study was to characterize changes in PanNET differentiation and proliferation over time and to correlate findings to overall survival (OS). PATIENTS AND METHODS: In this retrospective cohort study, we screened 475 PanNET patients treated at Uppsala University Hospital, Sweden. Sporadic patients with baseline and follow-up tumor samples were included. Pathology reports and available tissue sections were reevaluated with regard to tumor histopathology and Ki-67 index. RESULTS: Forty-six patients with 106 tumor samples (56 available for pathology reevaluation) were included. Median Ki-67 index at diagnosis was 7% (range 1-38%), grade 1 n = 8, grade 2 n = 36, and grade 3 n = 2. The median change in Ki-67 index (absolute value; follow-up - baseline) was +14% (range -11 to +80%). Increase in tumor grade occurred in 28 patients (63.6%), the majority from grade 1/2 to grade 3 (n = 24, 54.5%). The patients with a high-grade progression had a median OS of 50.2 months compared to 115.1 months in patients without such progression (hazard ratio 3.89, 95% CI 1.91-7.94, p < 0.001). CONCLUSIONS: A longitudinal increase in Ki-67 index and increase in tumor grade were observed in a majority of PanNETs included in this study. We propose that increase in Ki-67 index and high-grade progression should be investigated further as important biomarkers in PanNET.

Outcomes After Surgery for Unilateral Dominant Primary Aldosteronism in Sweden.

BACKGROUND: Primary aldosteronism (PA) is the most common cause of secondary hypertension. Surgery is the mainstay of treatment for unilateral dominant PA, but reported cure rates varies. The aim of the present study was to investigate contemporary follow-up practices and cure rates after surgery for PA in Sweden. METHODS: Patients operated for PA and registered in the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery (SQRTPA) 2009-2015 were identified. Patient data were extracted, and follow-up data (1-24 months) was recorded. Doses of antihypertensive medication and potassium supplementation were calculated using defined daily doses (DDD), and the Primary Aldosteronism Surgical Outcome (PASO) criteria were used to evaluate outcomes. RESULTS: Of 190 registered patients, 171 (47% female, mean age 53 years, median follow-up 3.7 months) were available for analysis. In 75 patients (44%), missing data precluded evaluation of biochemical cure according to the PASO criteria. Minimal invasive approach was used in 168/171 patients (98%). Complication rate (Clavien-Dindo >3a) was 3%. No mortality was registered. Pre/postoperatively 98/66% used antihypertensives (mean DDD 3.7/1.5). 89/2% had potassium supplementation (mean DDD 2.0/0) before/after surgery. Complete/partial biochemical and clinical success according to the PASO criteria were achieved in 92/7% and 34/60%, respectively. CONCLUSION: In this study, reflecting contemporary clinical practice in Sweden complete/partial biochemical and clinical success after surgery for PA was 92/7% and 34/60%. Evaluation of biochemical cure was hampered by lack of uniform reporting of relevant outcome measures. We suggest mandatory reporting of surgical outcomes using the PASO criteria for all units performing surgery for PA.

Incidence of wound dehiscence after colorectal cancer surgery: results from a national population-based register for colorectal cancer.

BACKGROUND: Patient-related risk factors for wound dehiscence after colorectal surgery remain obscure. METHODS: All open abdominal procedures for colorectal cancer registered in the Swedish Colorectal Cancer Registry (SCRCR, 5) 2007-2013 were identified. Potential risk factors for wound dehiscence were identified by cross-matching between the SCRCR and the National Patient Register (NPR). The endpoint in this study was reoperation for wound dehiscence registered in either the SCRCR or NPR and patients not reoperated were considered controls. RESULTS: A total of 30,050 patients were included in the study. In a multivariable regression analysis, age > 70 years, male gender, BMI > 30, history of chronic obstructive pulmonary disease, history of generalised inflammatory disease, and duration of surgery less than 180 min were independently and significantly associated with increased risk for wound dehiscence. A history of diabetes, chronic renal disease, liver cirrhosis, and distant metastases was not associated with wound dehiscence. The hazard ratio for postoperative death was 1.24 for patients who underwent reoperation for wound dehiscence compared with that for controls. DISCUSSION: Patients reoperated for wound dehiscence face a significantly higher postoperative mortality than those without. Risk factors include male gender, age > 70 years, obesity, history of chronic obstructive pulmonary disease, and history of generalised inflammatory disease. Patients at high risk for developing wound dehiscence may, if identified preoperatively, benefit from active prevention measures implemented in routine surgical practice.

Prospective observational study of 177Lu-DOTA-octreotate therapy in 200 patients with advanced metastasized neuroendocrine tumours (NETs): feasibility and impact of a dosimetry-guided study protocol on outcome and toxicity.

PURPOSE: Peptide receptor radionuclide therapy in patients with neuroendocrine tumours has yielded promising results. This prospective study investigated the feasibility of dosimetry of the kidneys and bone marrow during therapy and its impact on efficacy and outcome. METHODS: The study group comprised 200 consecutive patients with metastasized somatostatin receptor-positive neuroendocrine tumours progressing on standard therapy or not suitable for other therapeutic options. A treatment cycle consisted of 7.4 GBq 177Lu-DOTA-octreotate with co-infusion of a mixed amino acid solution, and cycles were repeated until the absorbed dose to the kidneys reached 23 Gy or there were other reasons for stopping therapy. The Ki-67 index was ≤2% in 47 patients (23.5%), 3-20% in 121 (60.5%) and >20% in 16 (8%). RESULTS: In 123 patients (61.5%) the absorbed dose to the kidneys reached 23 Gy with three to nine cycles during first-line therapy; in no patient was a dose to the bone marrow of 2 Gy reached. The best responses (according to RECIST 1.1) were a complete response (CR) in 1 patient (0.5%), a partial response (PR) in 47 (23.5%), stable disease (SD) in 135 (67.5%) and progressive disease (PD) in 7 (3.5%). Median progression-free survival was 27 months (95% CI 22-30 months) in all patients, 33 months in those in whom the absorbed dose to the kidneys reached 23 Gy and 15 months in those in whom it did not. Median overall survival (OS) was 43 months (95% CI 39-53 months) in all patients, 54 months in those in whom the absorbed dose to the kidneys reached 23 Gy and 25 months in those in whom it did not. Median OS was 60 months in patients with a best response of PR or CR, 42 months in those with SD and 16 months in those with PD. Three patients (1.5%) developed acute leukaemia, 1 patient (0.5%) chronic leukaemia (unconfirmed) and 30 patients (15%) grade 3 or 4 bone marrow toxicity. Eight patients (4%) developed grade 2 kidney toxicity and one patient (0.5%) grade 4 kidney toxicity. CONCLUSIONS: Dosimetry-based therapy with 177Lu-DOTA-octreotate is feasible. Patients in whom the absorbed dose to the kidneys reached 23 Gy had a longer OS than those in whom it did not. Patients with CR/PR had a longer OS than those with SD. Bone marrow dosimetry did not predict toxicity.

Decrease of 5-hydroxymethylcytosine and TET1 with nuclear exclusion of TET2 in small intestinal neuroendocrine tumors.

BACKGROUND: Small intestinal neuroendocrine tumors (SI-NETs) originate from enterochromaffin cells scattered in the intestinal mucosa of the ileum and jejunum. Loss of one copy of chromosome 18 is the most frequent observed aberration in primary tumors and metastases. The aim of this study was to investigate possible involvement of 5-hydroxymethylcytosine (5hmC), TET1 and TET2 in SI-NETs. METHODS: The analysis was conducted using 40 primary tumors and corresponding 47 metastases. The level of 5hmC, TET1 and TET2 was analyzed by DNA immune-dot blot assay and immunohistochemistry. Other methods included a colony forming assay, western blotting analysis, and quantitative bisulfite pyrosequencing analysis. The effect of the exportin-1 nuclear transport machinery inhibitors on cell proliferation and apoptosis was also explored using two SI-NET cell lines. RESULTS: Variable levels of 5hmC and a mosaic staining appearance with a mixture of positive and negative cell nuclei, regardless of cell number and staining strength, was observed overall both in primary tumors and metastases. Similarly aberrant staining pattern was observed for TET1 and TET2. In a number of tumors (15/32) mosaic pattern together with areas of negative staining was also observed for TET1. Abolished expression of TET1 in the tumors did not seem to involve hypermethylation of the TET1 promoter region. Overexpression of TET1 in a colony forming assay supported a function as cell growth regulator. In contrast to 5hmC and TET1, TET2 was also observed in the cytoplasm of all the analyzed SI-NETs regardless of nuclear localization. Treatment of CNDT2.5 and KRJ-I cells with the exportin-1 (XPO1/CRM1) inhibitor, leptomycin B, induced reduction in the cytoplasm and nuclear retention of TET2. Aberrant partitioning of TET2 from the nucleus to the cytoplasm seemed therefore to involve the exportin-1 nuclear transport machinery. Reduced cell proliferation and induction of apoptosis were observed after treatment of CNDT2.5 and KRJ-I cells with leptomycin B or KPT-330 (selinexor). CONCLUSIONS: SI-NETs are epigenetically dysregulated at the level of 5-hydroxymethylcytosine/ TET1/TET2. We suggest that KPT-330/selinexor or future developments should be considered and evaluated for single treatment of patients with SI-NET disease and also in combinations with somatostatin analogues, peptide receptor radiotherapy, or everolimus.

U-CAN: a prospective longitudinal collection of biomaterials and clinical information from adult cancer patients in Sweden.

BACKGROUND: Progress in cancer biomarker discovery is dependent on access to high-quality biological materials and high-resolution clinical data from the same cases. To overcome current limitations, a systematic prospective longitudinal sampling of multidisciplinary clinical data, blood and tissue from cancer patients was therefore initiated in 2010 by Uppsala and Umeå Universities and involving their corresponding University Hospitals, which are referral centers for one third of the Swedish population. MATERIAL AND METHODS: Patients with cancer of selected types who are treated at one of the participating hospitals are eligible for inclusion. The healthcare-integrated sampling scheme encompasses clinical data, questionnaires, blood, fresh frozen and formalin-fixed paraffin-embedded tissue specimens, diagnostic slides and radiology bioimaging data. RESULTS: In this ongoing effort, 12,265 patients with brain tumors, breast cancers, colorectal cancers, gynecological cancers, hematological malignancies, lung cancers, neuroendocrine tumors or prostate cancers have been included until the end of 2016. From the 6914 patients included during the first five years, 98% were sampled for blood at diagnosis, 83% had paraffin-embedded and 58% had fresh frozen tissues collected. For Uppsala County, 55% of all cancer patients were included in the cohort. CONCLUSIONS: Close collaboration between participating hospitals and universities enabled prospective, longitudinal biobanking of blood and tissues and collection of multidisciplinary clinical data from cancer patients in the U-CAN cohort. Here, we summarize the first five years of operations, present U-CAN as a highly valuable cohort that will contribute to enhanced cancer research and describe the procedures to access samples and data.

Incisional hernia after surgery for colorectal cancer: a population-based register study.

BACKGROUND: Our knowledge on the incidence of incisional hernia and risk factors for developing incisional hernia following surgery for colorectal cancer is far from complete. METHODS: All procedures registered in the Swedish Colorectal Cancer Register (SCRCR) 2007-2013 were identified. Patients with comorbid disease diagnoses, registered at admissions and visits prior to the procedure and relevant to this study, were obtained from the National Patient Register (NPR). These diagnoses included cardiovascular disease, connective tissue disorders, liver cirrhosis, renal failure, diabetes, chronic obstructive lung disease and chronic inflammatory conditions. Data on occurrence of incisional hernias were obtained by combining data from the SCRCR and the NPR (International Classification of Diseases code). RESULTS: During 2007-2013, 39,984 procedures were registered in the SCRCR. After excluding laparoscopic procedures, procedures repeated on the same patient, procedures with concomitant liver resection and procedures without laparotomy, 28,913 cases remained for analysis. Five years after surgery, the cumulative incidence of incisional hernia was 5.3%. In multivariate proportional hazard analysis, significantly increased risk for incisional hernia was found for the male gender (hazard ratio [HR] 1.40, 95% confidence interval [CI] 1.21-1.62), operation time exceeding 180 min (HR 1.25, CI 1.08-1.45), body mass index (BMI) > 30 (HR 1.78, CI 1.51-2.09), age < 70 years (HR 1.34, CI 1.16-1.56) and postoperative wound complication (HR 2.09, CI 1.70-2.58). DISCUSSION: Men, patients younger than 70 years and patients with BMI > 30 face a higher risk for incisional hernia. The risk is also increased in cases where the procedure takes longer than 3 h or where postoperative wound complications occur. These patients will benefit from measures aimed at preventing the development of incisional hernia.

Preoperative 68Ga-DOTA-Somatostatin Analog-PET/CT Hybrid Imaging Increases Detection Rate of Intra-abdominal Small Intestinal Neuroendocrine Tumor Lesions.

BACKGROUND: Small intestinal neuroendocrine tumors (SI-NETs) are the most common form of neoplasm in the small bowel. Radiological identification of primary tumors (PT), which may be multiple, is difficult, and therefore palpation of the entire small bowel is routinely performed during laparotomy. The aim was to determine detection rates of PT and peritoneal carcinomatosis (PC) with 68Ga-DOTATOC/TATE-PET/CT in comparison with i.v. contrast-enhanced computed tomography (CE-CT) and thus to clarify whether modern functional imaging can mitigate the need for palpation of bowel during surgery enabling oncologically adequate laparoscopic resection. METHODS: A total of 28 patients with SI-NET who preoperatively underwent both 68Ga-DOTATOC/TATE-PET/CT and CE-CT were included. The detection rates of PT and PC for PET/CT and CE-CT were compared to the findings in the surgical and histopathological reports. Appropriate statistical tests were used, and significance was set to p < 0.05. RESULTS: Out of 82 PT, 43 PT were not detected by any imaging modality. More PT lesions were detected with PET/CT (n = 39 [47.5%]) than with CE-CT (n = 10 [12.2%], p < 0.001). Also, PET/CT identified significantly more PC lesions than CE-CT (78 and 38%, p = 0.004, respectively). CONCLUSION: PET/CT detected more PT and PC lesions than CE-CT. Some PTs and PC lesions were only detected by one of the modalities, and CT performed in conjunction with PET/CT should therefore be performed as a fully diagnostic CE-CT for optimal results. Palpation of the small bowel remains crucial during surgery in these patients because several PTs escaped detection by both PET/CT and CE-CT.

Neomorphic effects of recurrent somatic mutations in Yin Yang 1 in insulin-producing adenomas.

Insulinomas are pancreatic islet tumors that inappropriately secrete insulin, producing hypoglycemia. Exome and targeted sequencing revealed that 14 of 43 insulinomas harbored the identical somatic mutation in the DNA-binding zinc finger of the transcription factor Yin Yang 1 (YY1). Chromatin immunoprecipitation sequencing (ChIP-Seq) showed that this T372R substitution changes the DNA motif bound by YY1. Global analysis of gene expression demonstrated distinct clustering of tumors with and without YY1(T372R) mutations. Genes showing large increases in expression in YY1(T372R) tumors included ADCY1 (an adenylyl cyclase) and CACNA2D2 (a Ca(2+) channel); both are expressed at very low levels in normal ß-cells and show mutation-specific YY1 binding sites. Both gene products are involved in key pathways regulating insulin secretion. Expression of these genes in rat INS-1 cells demonstrated markedly increased insulin secretion. These findings indicate that YY1(T372R) mutations are neomorphic, resulting in constitutive activation of cAMP and Ca(2+) signaling pathways involved in insulin secretion.

The Influence of Preoperative Symptoms on the Death of Patients with Small Intestinal Neuroendocrine Tumors.

BACKGROUND: Small intestinal neuroendocrine tumors (SI-NETs) are uncommon tumors with an annual incidence of about 1 per 100,000. Usually, SI-NETs have a slow progression, and patients often present with generalized disease. Many patients do well, and the disease has a relatively favorable 5-year survival rate. Some SI-NETs, however, have a more negative prognosis. This study aimed to establish prognostic factors for death identifiable at primary surgery. METHODS: A nested case-control study investigated 1150 patients from the cohort of all patients with a diagnosis of SI-NETs in Sweden between 1961 and 2001. The study cases consisted of all patients who died of SI-NETs during the study period. Each case was assigned a control subject matched by age at diagnosis and calendar period. Possible prognostic factors [gender, degree of symptoms, indication for surgery, World Health Organization (WHO) stage] were evaluated in uni- and multivariable analyses. RESULTS: The patients with symptomatic disease had an increased risk of dying. The indication for primary surgery influenced survival, showing a more negative prognosis for elective surgery. The WHO stage influenced survival, and stage 4 patients had an almost threefold risk of dying compared with stages 1 to 3b patients. CONCLUSIONS: This study showed that preoperative symptoms are important in prognostication for SI-NETs. Hormonal symptoms generally signify a patient with a more advanced disease stage and a worse prognosis. Including symptomatic disease together with the WHO stage and grade could possibly increase the accuracy of prognostication.

DcR3, TFF3, and Midkine Are Novel Serum Biomarkers in Small Intestinal Neuroendocrine Tumors.

Small intestinal neuroendocrine tumors (SI-NETs) are amine- and peptide-producing neoplasms. Most patients display metastases at the time of diagnosis; they have an unpredictable individual disease course and the tumors are often therapy resistant. Chromogranin A and 5-hydroxyindoleacetic acid are the biomarkers clinically used most often today, but there is a great need for novel diagnostic and prognostic biomarkers and new therapeutic targets. Sixty-nine biomarkers were screened in serum from 23 SI-NET patients and 23 healthy controls using the multiplex proximity ligation assay (PLA). A refined method, the proximity extension assay (PEA), was used to analyze 76 additional biomarkers. Statistical testing and multivariate classification were performed. Immunohistochemistry and ELISA were performed in an extended cohort. Using PLA, 19 biomarkers showed a significant difference in serum concentrations between patients and controls, and PEA revealed a difference in the concentrations of 17 proteins. Multivariate classification analysis revealed decoy receptor 3 (DcR3), trefoil factor 3 (TFF3), and midkine to be good biomarkers for the disease, which was confirmed by ELISA analysis. All 3 biomarkers were expressed in tumor tissue. DcR3 concentrations were elevated in patients with stage IV disease. High concentrations of DcR3 and TFF3 were correlated to poor survival. DcR3, TFF3, and midkine exhibited elevated serum concentrations in SI-NET patients compared to healthy controls, and DcR3 and TFF3 were associated with poor survival. DcR3 seems to be a marker for liver metastases, while TFF3 and midkine may be new diagnostic biomarkers for SI-NETs.

Preclinical Evaluation of AdVince, an Oncolytic Adenovirus Adapted for Treatment of Liver Metastases from Neuroendocrine Cancer.

Cancer immunotherapy is becoming a cornerstone in the clinical care of cancer patients due to the breakthrough trials with immune checkpoint blockade antibodies and chimeric antigen receptor T cells. The next breakthrough in cancer immunotherapy is likely to be oncolytic viruses engineered to selectively kill tumor cells and deceive the immune system to believe that the tumor is a foreign entity that needs to be eradicated. We have developed AdVince, an oncolytic adenovirus for treatment of liver metastases from neuroendocrine tumor (NET). AdVince includes the gene promoter from human chromogranin A for selective replication in neuroendocrine cells, miR122 target sequences for reduced liver toxicity, and a cell-penetrating peptide in the capsid for increased infectivity of tumor cells and optimized spread within tumors. This paper describes the preclinical evaluation of AdVince on freshly isolated human gastrointestinal NET cells resected from liver metastases and freshly isolated human hepatocytes as well as in fresh human blood. AdVince selectively replicates in and kills NET cells. Approximately 73-fold higher concentration of AdVince is needed to induce a similar level of cytotoxicity in NET cells as in hepatocytes. AdVince did not activate complement or induce considerable amount of proinflammatory cytokines or chemokines in human blood. The data presented herein indicate that AdVince can be safely evaluated in a phase I/IIa clinical trial for patients with liver-dominant NET.

A plausible role for actin gamma smooth muscle 2 (ACTG2) in small intestinal neuroendocrine tumorigenesis.

BACKGROUND: Small intestinal neuroendocrine tumors (SI-NETs) originate from the enterochromaffin cells in the ileum and jejunum. The knowledge about genetic and epigenetic abnormalities is limited. Low mRNA expression levels of actin gamma smooth muscle 2 (ACTG2) have been demonstrated in metastases relative to primary SI-NETs. ACTG2 and microRNA-145 (miR-145) are aberrantly expressed in other cancers and ACTG2 can be induced by miR-145. The aim of this study was to investigate the role of ACTG2 in small intestinal neuroendocrine tumorigenesis. METHODS: Protein expression was analyzed in SI-NETs (n = 24) and in enterochromaffin cells by immunohistochemistry. The cell line CNDT2.5 was treated with the histone methyltransferase inhibitor 3-deazaneplanocin A (DZNep), the selective EZH2 inhibitor EPZ-6438, or 5-aza-2'-deoxycytidine, a DNA hypomethylating agent. Cells were transfected with ACTG2 expression plasmid or miR-145. Western blotting analysis, quantitative RT-PCR, colony formation- and viability assays were performed. miR-145 expression levels were measured in tumors. RESULTS: Eight primary tumors and two lymph node metastases displayed variable levels of positive staining. Fourteen SI-NETs and normal enterochromaffin cells stained negatively. Overexpression of ACTG2 significantly inhibited CNDT2.5 cell growth. Treatment with DZNep or transfection with miR-145 induced ACTG2 expression (>10-fold), but no effects were detected after treatment with EPZ-6438 or 5-aza-2'-deoxycytidine. DZNep also induced miR-145 expression. SI-NETs expressed relatively low levels of miR-145, with reduced expression in metastases compared to primary tumors. CONCLUSIONS: ACTG2 is expressed in a fraction of SI-NETs, can inhibit cell growth in vitro, and is positively regulated by miR-145. Theoretical therapeutic strategies based on these results are discussed.