An integrative correlation of myopathology, phenotype and genotype in late onset Pompe disease

AIMS

Pompe disease is caused by pathogenic mutations in the alpha 1,4-glucosidase (GAA) gene and in patients with late onset Pome disease (LOPD), genotype-phenotype correlations are unpredictable. Skeletal muscle pathology includes glycogen accumulation and altered autophagy of various degrees. A correlation of the muscle morphology with clinical features and the genetic background in GAA may contribute to the understanding of the phenotypic variability.

METHODS

Muscle biopsies taken before enzyme replacement therapy were analysed from 53 patients with LOPD. On resin sections, glycogen accumulation, fibrosis, autophagic vacuoles and the degree of muscle damage (morphology-score) were analysed and the results were compared with clinical findings. Additional autophagy markers microtubule-associated protein 1A/1B-light chain 3, p62 and Bcl2-associated athanogene 3 were analysed on cryosections from 22 LOPD biopsies.

RESULTS

The myopathology showed a high variability with, in most patients, a moderate glycogen accumulation and a low morphology-score. High morphology-scores were associated with increased fibrosis and autophagy highlighting the role of autophagy in severe stages of skeletal muscle damage. The morphology-score did not correlate with the patient's age at biopsy, disease duration, nor with the residual GAA enzyme activity or creatine-kinase levels. In 37 patients with LOPD, genetic analysis identified the most frequent mutation, c.-32-13T>G, in 95%, most commonly in combination with c.525delT (19%). No significant correlation was found between the different GAA genotypes and muscle morphology type.

CONCLUSIONS

Muscle morphology in LOPD patients shows a high variability with, in most cases, moderate pathology. Increased pathology is associated with more fibrosis and autophagy.

Long-term growth hormone (GH) replacement of adult GH deficiency (GHD) benefits the heart

OBJECTIVE

Growth hormone (GH) deficiency is related to increased cardiovascular mortality. We studied clinical status, concentration of amino-terminal-pro B-type natriuretic-peptide (NT-proBNP) and echocardiographic parameters during long-term GH replacement (GH-R).

METHODS

Fifty-one patients (29 females), 45.9 ± 11.3 years (mean ± s.d.), median follow-up 36.2 months, echocardiography and laboratory determinations initially and at 12-months intervals.

RESULTS

At the last follow-up (last observation carried forward) (LFU (LOCF)) insulin-like growth-factor-1 standard deviation score (IGF-1 SDS) was ±1 in 92% of the patients. The median NT-proBNP declined significantly and stabilized (-40.5%) at LFU (LOCF) due to patients with a basal NT-proBNP >125 ng/L (indicative of heart failure). The basal NT-proBNP and the final IGF-1 SDS were significant predictors of the NT-proBNP at LFU (LOCF). Initially left ventricular enddiastolic diameter (LVEDD), left ventricular posterior wall diameter (LVPWD) and ejection fraction (EF) were normal, while interventricular septum diameter (IVSD) and left ventricular mass index (LVMi) were slightly increased. LVPWD and IVSD had significantly declined by year three. The LVMi was moderately to severely abnormal in 37.3 and 52.0% of patients initially and at LFU (LOCF). At LFU (LOCF) LVMi and IGF-1 were significantly correlated in the 14 male patients of this subgroup.

CONCLUSION

Long-term GH-R of GHD positively affected ISVD and LVPWD. In a subgroup of patients with severe GHD, LVMi increased concomitantly to the decline in NT-proBNP and this was positively correlated to the final IGF-1 concentration. Whether this observation indicates a positive development in a structurally altered heart muscle (reversal of adverse remodelling) or poses a future risk for heart failure needs further follow-up.

The German National Action League for people with rare diseases: translating the three tiers center system into active co-operation, a one center experience

Introduction

In 2009 the European Commission called for National action plans (NAP) to improve the care for persons with rare diseases. Germany set up a NAP in 2013 suggesting a three-tiered structure of co-operating centers (CC), centers of excellence (CE) and reference centers (CR). Since then CEs and CRs were organized in the framework of university hospitals. However, realization of CCs taking into account the requirements of the NAP has been slow. We therefore set-up a 12-months program to initiate co-operation and to support the development of structured CCs.

Methods

Our center invited 3000 physicians from Berlin and/or Brandenburg to participate. They were chosen either due to already referring patients with rare metabolic diseases to the center, residing in a neighborhood with diverse ethnic background, known to have a high prevalence for specific metabolic diseases, or working as a medical sub-specialist (gastroenterology, hematology, rheumatology) with a high probability to diagnose a rare metabolic disease. The center offered co-operation contracts, administrative and structured medical support, privileged access to the center for physicians and their patients, as well as a program of continuous medical education (CME) over a period of 12 months.

Results

Between 0.1 to 0.5% (mean 0.2%) of the invited physicians participated in CME meetings. None of them was interested in setting up a co-operating center. The physicians were interested in broadening their knowledge about rare diseases, but less so in direct care for these patients and not at all in fulfilling the requirements of the NAP.

Conclusions

The requirements of the NAP for CC are thought of as unrealistic due to their demands on structural re-organization, quality measurements and additional work-load for outpatient-care. Especially so, with respect for the low number of patients profiting from these efforts and the lack of re-imbursement. We suggest a reconsideration of the German NAP.

Multi-centre phase IV trial to investigate the immunogenicity of a new liquid formulation of recombinant human growth hormone in adults with growth hormone deficiency

PURPOSE

To investigate whether a new liquid formulation of recombinant human growth hormone (r-hGH) induces the production of binding antibodies (BAbs) in adults with congenital or adult-onset growth hormone deficiency (GHD).

METHODS

Men or women aged 19-65 years with adult growth hormone deficiency who were r-hGH-naïve or had stopped treatment ≥ 1 month before screening were treated with between 0.15 and 0.30 mg/day r-hGH liquid formulation for 39 weeks. The primary endpoint was the proportion of patients who developed BAbs at any time. Secondary endpoints were the proportion of patients with BAbs who became positive for neutralising antibodies, the effects on biomarkers of r-hGH exposure, safety, and adherence to treatment downloaded from the easypod™ connect software.

RESULTS

Seventy-eight patients (61.5% men) with mean age 44.5 years (range 21-65) started and 68 (87.2%) completed the 39-week treatment period. 82.1% were treatment naïve; all were negative for BAbs to r-hGH at baseline. The median (interquartile range) duration of treatment [273 (267.0-277.0) days] was consistent with patients receiving the required doses, and mean treatment adherence measured using easypod™ connect was 89.3%. The proportion of patients who developed BAbs was 0% (95% confidence interval 0-4.68%) and biomarker profiles were consistent with exposure to r-hGH. 92.3% of patients reported ≥ 1 adverse event during treatment. Most events were mild or moderate and no new safety concerns were detected.

CONCLUSIONS

The low immunogenicity profile of the liquid formulation was consistent with that for the freeze-dried formulation, and no new safety concerns were reported.

2-deoxy-2-[18]fluoro-D-glucose PET/CT (18FDG PET/CT) may not be a viable biomarker in Pompe disease

Background

Pompe disease (PD) is an autosomal recessive, lysosomal storage disease due to a mutation of the acid α-glucosidase (GAA) gene. In adult patients, PD is characterized by slowly progressive limb-girdle and trunk myopathy and restrictive respiratory insufficiency. Enzyme replacement therapy (ERT) is available, improving or stabilizing muscle-function in some and slowing deterioration in other patients. Unfortunately, there is no biomarker available to indicate therapeutic efficacy and/or disease activity. Whole body MRI depicts all skeletal muscles demonstrating foci of atrophic muscles, i.e., late and irreversible pathological changes. Any method indicating the localizations of increased muscle glycogen storage, muscle inflammation and/or degradation could possibly help identifying newly afflicted tissue and may be of prognostic value. We therefore investigated 2-deoxy-2-[18]fluoro-D-glucose (FDG) PET, a biomarker for glucose-metabolism, as a tool to evaluate disease activity and prognosis in PD.

Methods

In a pilot study, we investigated four patients by FDG dynamic PET/CT while on ERT. One patient had FDG-PET/CT twice, before and after 12 months on ERT. Dynamic FDG-PET/CT quantifies the metabolic rate of glucose utilisation in mg/ml/min. MRI was performed in parallel with pelvic and thigh muscles semi-quantitatively scored for atrophy and disease-activity.

Results

None of the muscles analysed showed a focally increased FDG-uptake. Thus, quantification of muscle glucose metabolism could not be calculated. However, increased FDG-uptake, i.e., increased glucose utilisation, was observed in the respiratory muscles of one patient with severe, restrictive respiratory failure. In contrast, specific MRI sequences showed oedematous as well as atrophic muscle areas in PD.

Conclusions

Our pilot study demonstrates that FDG-uptake does not correlate with glycogen storage in vivo. In contrast, MRI is an excellent tool to demonstrate the extent of muscle involvement. Specific MRI sequences may even demonstrate early changes possibly allowing prognostic predictions or localization of early stages of PD.

Management goals for type 1 Gaucher disease: An expert consensus document from the European working group on Gaucher disease

Gaucher Disease type 1 (GD1) is a lysosomal disorder that affects many systems. Therapy improves the principal manifestations of the condition and, as a consequence, many patients show a modified phenotype which reflects manifestations of their disease that are refractory to treatment. More generally, it is increasingly recognised that information as to how a patient feels and functions [obtained by patient- reported outcome measurements (PROMs)] is critical to any comprehensive evaluation of treatment. A new set of management goals for GD1 in which both trends are reflected is needed. To this end, a modified Delphi procedure among 25 experts was performed. Based on a literature review and with input from patients, 65 potential goals were formulated as statements. Consensus was considered to be reached when ≥75% of the participants agreed to include that specific statement in the management goals. There was agreement on 42 statements. In addition to the traditional goals concerning haematological, visceral and bone manifestations, improvement in quality of life, fatigue and social participation, as well as early detection of long-term complications or associated diseases were included. When applying this set of goals in medical practice, the clinical status of the individual patient should be taken into account.

[Neuroendocrine tumours of the GI tract--data from the German NET Registry]

BACKGROUND

Neuroendocrine tumours (NET) are rare and heterogeneous neoplasia. To obtain valid data on epidemiology, diagnostics, therapy, prognosis and risk factors is the aim of the German NET registry.

PATIENTS AND METHODS

Data from 2009 histologically proven NET were collected from 35 NET centres between 1999 and 2010. Data collection has been performed prospectively since 2004. Results: Median follow-up was 34.5 months and median age at diagnosis 56.4 years. Primary tumour localisations were pancreas (34.2%), midgut (5.8%), stomach (6.5%), bowel (6.9%), duodenum (4.8%) and neuroendocrine CUP (12.6%). Synchronous metastases were seen in 46% and second malignancies in 12%. From 860 patients, 402 (46.7%) had functional tumours with the following hormone excess syndromes: carcinoid syndrome (19.1%; n = 164), persistent hyperinsulinaemic hypoglycaemia (17.7%; n = 152), Zollinger- Ellison syndrome (7.1%; n = 61), glucagonoma (0.7%; n = 15), Verner-Morrison syndrome (0.4%; n = 8) and somatostatinoma syndrome(0.1%; n = 2). Surgical therapy was performed in 78%, therapy with somatostatin receptor analogues(SSA) in 28%, peptide radioreceptor therapy (PRRT) in 19%, chemotherapy in 18% and interferon therapy in 6.5%. Only surgery was done in 47%, whereas 53% received a second therapy. General mortality rate during follow-up was 14.9%. The tumour-specific survival rates for 2, 5 and 10 years were 94, 85 and 70%. The 5-year survival is dependent on the surgical or non-surgical therapy (82 versus 61%, p < 0.001) and also on the primary tumour site (90/30% for midgut, 85/65% for pancreas, p < 0.001). Grading (G1, G2, G3) based on proliferation index Ki-67 recommended by the ENETS guidelines and WHO classification is highly correlated to the 5-year survival rate (88, 82, 33%, p < 0.001).

CONCLUSION

The German NET registry provides valid multicentric data on NET in Germany. Surgical therapy is the most frequent and important therapy with good clinical outcome. In non-resectable, metastatic tumours, systemic therapies are common. Continuation and evaluation of the new WHO and TNM classifications for NET and their therapies will be a future focus of the registry.

DG3173 (somatoprim), a unique somatostatin receptor subtypes 2-, 4- and 5-selective analogue, effectively reduces GH secretion in human GH-secreting pituitary adenomas even in Octreotide non-responsive tumours

OBJECTIVE

Somatostatin analogues (SSA) reduce autonomous GH secretion by activating somatostatin receptors (sst) 2 and 5 in 50-60% of acromegalic patients. However, by inhibiting insulin secretion these SSA reduce glucose tolerance. DG3173 is a novel SSA with additional binding to sst4 and low insulin-suppressing activity. We investigated the effect of DG3173, including its relation to specific tumour characteristics, on GH secretion in human somatotroph adenoma cell cultures (hSA) in comparison with Octreotide.

METHODS

Twenty-seven hSA were characterised immunohistochemically for their hormone- and sst-expression, granularity and pre-surgical therapy with SSA. GH was determined in supernatants of hSA treated with DG3173 or Octreotide in time- (n=6) and dose-response (n=21) experiments. A positive response was defined as GH suppression to below 80% of baseline.

RESULTS

In the dose-response experiments DG3173 suppressed GH secretion in more adenomas than Octreotide (10/21 vs 5/21), including 38% (6/16) of Octreotide non-responders. In responders the extent of GH suppression and IC(50) were comparable for both SSA. The response-rate of both SSA was higher in monohormonal vs bihormonal adenomas, yet GH declined similarly in both groups. Neither pre-surgical SSA (n=6) nor tumour morphology was related to the GH response. However, semi-quantitative analysis indicated a small but significant negative correlation between the GH response to Octreotide and the immunoreactivity scores of sst2 expression.

CONCLUSIONS

DG3173 equalled Octreotide in suppressing GH secretion in hSA. Since DG3173 suppressed GH in some Octreotide-non-responsive adenomas, its clinical effectiveness will be worth testing. Moreover, its reduced insulin-suppressive potency would make it a valuable alternative to Octreotide.

Medical therapy of acromegaly

This paper outlines the present status of medical therapy of acromegaly. Indications for permanent postoperative treatment, postirradiation treamtent to bridge the interval until remission as well as primary medical therapy are elaborated. Therapeutic efficacy of the different available drugs-somatostatin receptor ligands (SRLs), dopamine agonists, and the GH antagonist Pegvisomant-is discussed, as are the indications for and efficacy of their respective combinations. Information on their mechanism of action, and some pharmakokinetic data are included. Special emphasis is given to the difficulties to define remission criteria of acromegaly due to technical assay problems. An algorithm for medical therapy in acromegaly is provided.

Efficacy and acceptability of lanreotide Autogel® 120 mg at different dose intervals in patients with acromegaly previously treated with octreotide LAR

OBJECTIVE

To assess the efficacy of different dosing intervals of lanreotide, Somatuline Autogel® (Lan-ATG) 120 mg in patients with acromegaly, previously treated with octreotide, long-acting release (Oct-LAR).

PATIENTS AND STUDY DESIGN

Patients previously on Oct-LAR 10, 20, or 30 mg were switched to 6 repeated deep subcutaneous injections of Lan-ATG 120 mg at intervals of 56, 42, or 28 days, respectively. After the third injection, dose intervals were adjusted on the basis of insulin-like growth factor 1 (IGF-1) levels.

RESULTS

The ITT (Intention To Treat) population comprised 35 patients who received at least one dose of study medication and at least one post-baseline efficacy assessment. Overall, 62.9% (n=22) of patients had normalised IGF-1 levels with Lan-ATG at study end (one injection interval after the 6 (th) injection of Lan-ATG), which was similar to the proportion at baseline (60.0% [n=21]). QoL did not change from baseline to study end. Patient preference for Lan-ATG was highest in the 56-day dosing interval group: 71%, 54% and 41% of the patients in the 56, 42 and 28 day groups, respectively, expressed a preference for treatment with Lan-ATG (preference for Oct-LAR: 29%, 9% and 35%, respectively, while the remainder had no preference).

CONCLUSION

Lan-ATG 120 mg injected at intervals of 56, 42 and 28 days provided equivalent hormonal control and QoL to Oct-LAR 10, 20 and 30 mg injected every 28 days, respectively. The proportion of patients preferring Lan-ATG treatment was greater in the longer injection interval groups.

Problems of diabetes management in the immigrant population in Germany

AIM

To compare prospectively the effect of diabetes management in the immigrant and the native population in Berlin, Germany.

METHODS

Diabetes patients attending a metabolic outpatient clinic in an area with a high immigrant population were studied at the start of the training program and after 12 months of participation.

RESULTS

1607 of 2099 patients with at least one post-training visit (76.6%) provided analysable data. Of these 362 (22.5%) were immigrants. Initial hemoglobin A1c (HbA1c) was higher in the immigrants. Immigrants were 5 years younger and had a more recent diagnosis of diabetes. HbA1c fell by 1.4 and 1.5 percentage points in the immigrants and natives, leaving a greater proportion of the immigrants above the target value of 6.5%. Analysis of patients matched according to baseline HbA1c, sex and age showed a smaller decrease in mean HbA(1c) for the immigrants. The percent of patients with hypertension, obesity, dyslipidaemia or diabetic complications was comparable in both groups initially and after 12 months.

CONCLUSION

Immigrants had a higher HbA1c concentration at baseline and after 12 months compared to natives, despite a similar decline in HbA1c percentage points. More investigations are warranted to identify the causes, such as dietary habits, language difficulties, education and others.

Results of surgical and somatostatin analog therapies and their combination in acromegaly: a retrospective analysis of the German Acromegaly Register

BACKGROUND

Data on surgical and medical treatment outcomes in acromegaly mostly originate from specialized centers. We retrospectively analyzed the data on surgery, primary somatostatin analog (SSA) therapy, surgery preceded by SSA, and SSA preceded by surgery in 1485 patients from the German Acromegaly Register.

METHODS

Two trained nurses visited all centers (N=42) for data acquisition.

RESULTS

Primary surgery: out of 889 patients, 554 yielded analyzable data (microadenomas 22.9%, macroadenomas 77.1%). GH and IGF1 normalized in 54.3 and 67.2%. Partial or total pituitary insufficiency occurred in 28.6% initially and 41.2% post-surgery. Primary SSA (>or=3 months): out of 329 patients, 145 yielded analyzable data (microadenomas 26.7%, macroadenomas 73.3%). GH and IGF1 normalized in 36.3 and 30.5%, increasing to 40.8 and 41.5% with longer SSA (>or=360 days) in 54 patients. Pituitary function did not change. SSA (>or=3 months) prior to surgery: out of 234 patients, 93 yielded analyzable data. Post-surgery GH and IGF1 was normalized in 62.9 and 68.4%. GH improvement was slightly, but significantly better after SSA pretreatment. Surgery followed by SSA: out of 122 patients, 34 yielded analyzable data. GH and IGF1 normalized during SSA in 24.1 and 45.5%. Relative GH decrease was significantly larger compared with primary SSA.

CONCLUSIONS

Pituitary surgery was more effective to lower GH and IGF1 concentrations than primary SSA. Primary SSA may be an option in selected patients. SSA prior to surgery only marginally improved surgical outcome. Debulking surgery may result in better final outcome in patients with a high GH concentration and a large tumor.

Pegvisomant increases intra-abdominal fat in patients with acromegaly: a pilot study

OBJECTIVE

Acromegalic patients have increased lipolysis and decreased fat mass as well as reduced insulin sensitivity and glucose intolerance. During somatostatin analog therapy, these changes persist despite GH suppression, but they are now due to drug-induced suppression of insulin secretion. By contrast, during pegvisomant (PEG) therapy, GH no longer stimulates lipolysis due to the blockade of its receptor, while insulin action is unabated. Hence, both insulin sensitivity and fat mass, including intra-abdominal fat, should increase. We therefore studied intra-abdominal fat and insulin resistance in acromegalic patients after a 3-month octreotide-washout period, i.e., during untreated acromegaly, and during PEG treatment.

METHODS

Five acromegalic patients, not controlled on octreotide (OCT) therapy, were studied after 3-month OCT washout and 6-month PEG therapy. Insulin sensitivity was determined by homeostatic model assessment value and hyperinsulinemic, normoglycemic clamp. Subcutaneous and intra-abdominal fat were measured by electron beam computed tomography.

RESULTS

During PEG therapy, all the patients had normal, age-adjusted IGF-I concentrations. Compared with washout, insulin sensitivity (HOMA and M value) was not significantly different. However, intra-abdominal fat mass increased significantly during therapy (median (range) cm(2): 112 (84-480) and 172 (112-524) respectively, P<0.05), while subcutaneous fat was not significantly different. Low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides remained unchanged.

CONCLUSIONS

During PEG therapy of acromegalic patients, intra-abdominal fat increases. Visceral obesity is a risk factor for cardiovascular disease. Hence, confirmation and further studies in a larger cohort of acromegalic patients on PEG treatment are warranted.

Treatment of gastroenteropancreatic neuroendocrine tumors

Neuroendocrine tumors are rare; thus, individual experience with the diagnosis and treatment of these tumors is mostly low, except in specialized centers. For histological diagnosis, standards have been described recently. Pathological classification and clinical staging influence diagnostic and therapeutic decisions. This chapter aims at demonstrating the importance of pathological and clinical classification of neuroendocrine tumors on therapeutic decisions, indicating the appropriate therapy for different stages of the disease. Surgical therapy will be discussed shortly, including palliative surgical strategies. However, the focus of the manuscript is medical therapy. Biotherapy, its effects, and remaining uncertainties are presented as well as different chemotherapeutic schemes. Finally, new options of palliative medical therapies like kinase inhibitors and anti-angiogenetic drugs will be discussed.

Short stature and decreased insulin-like growth factor I (IGF-I)/growth hormone (GH)-ratio in an adult GH-deficient patient pointing to additional partial GH insensitivity due to a R179C mutation of the growth hormone receptor

OBJECTIVE

Genetic factors play an expanding role in understanding growth hormone (GH) disorders, therefore the German KIMS Pharmacogenetics Study was initiated with the aim of genotyping various GH-/IGF-I-axis-related genes of GH-deficient adult patients to investigate genotype:phenotype relationships and response to GH therapy.

PATIENTS AND METHODS

129 consecutively enrolled GH-deficient adult patients were genotyped for variant 1 (V1) of the alternatively spliced noncoding exons in the 5'-untranslated region and for the nine coding exons of the GH receptor (GHR) gene, which obviously play a striking role in the function of the GH-IGF-I-axis. After detection of a heterozygous, non-synonymous mutation R179C in exon 6 in one single patient with acquired GH-deficiency (GHD) in late adulthood, analysis of her clinical data followed, leading to the diagnosis of mild short stature (-1.5SD). For further endocrine evaluation, five pituitary stimulation tests (arginine) of this patient were statistically compared to stimulation tests (arginine) of ten GH-deficient control patients, retrospectively.

RESULTS

The formerly in patients with Laron syndrome and idiopathic short stature reported mutation R179C leads to an amino acid change from an arginine residue (codon CGC) to a cysteine residue (codon TGC) in position 179 of the extracellular domain of the GHR. Statistical analysis revealed significant decreased IGF-I/GH(0) ratio (p=0.004) and IGF-I/GH(max) ratio (p=0.001) of the index patient compared to the control patients, implying growth hormone resistance of the index patient at the level of the GHR, according to the detected R179C mutation.

CONCLUSIONS

This study reports on the unusual case of a patient with mild short stature, who acquired GHD in late adulthood due to a non-secreting pituitary adenoma and get additionally diagnosed for pre-existing growth hormone insensitivity due to a formerly in two short statured patients described, single, heterozygous, non-synonymous mutation in the GHR. Our findings support the theory that heterozygous mutations in the GHR gene can have mild phenotypical consequences.

Neuroendocrine tumors. Biotherapy

This review gives an introduction to the classification and staging of neuroendocrine tumors, as the prognostic implications of these classifications influence therapeutic decisions. The indications for biotherapy are given, together with a short update on the mechanism of somatostatin analogs and interferon-alpha therapy. This is followed by an in-depth description of the use of biotherapy, its results with respect to symptomatic and antiproliferative treatment, as well as its side-effects.

Oxaliplatin plus 5-fluorouracil/folinic acid as palliative treatment for progressive malignant gastrointestinal neuroendocrine carcinomas

14074

Background: Oxaliplatin in combination with 5-fluorouracil and folinic acid is an antitumoral agent with relatively low toxicity and satisfactory efficacy in several gastrointestinal neoplasms. However, it has not been studied in malignant gastrointestinal neuroendocrine carcinomas (NEC) for which platinum-based chemotherapy is a standard treatment with considerable toxicity. Methods: 16 patients (6 female, 10 male; mean age 57) with documented progress of histologically proven, irresectable, malignant NEC were retrospectively analyzed for safety and efficacy of cytotoxic treatment (from october 2001 to december 2005) according to the FOLFOX-4 regimen. Primary tumors were in the foregut in 9 (2 bronchial, 5 pancreas, 2 stomach), in the midgut in 3 (1 ileum, 2 coecum), and in the hindgut in 2 (1 colon, 1 rectum) patients. The primary tumor was unknown in 2 patients. No patient had clinical signs of hormone hypersecretion. NEC were low-grade malignant in 8 and high grade malignant in the remaining 8 cases. The ki67-index was ≥ 10% in 13 cases (81.3%). Results: A mean of 7.25 cycles (range 1–19) of FOLFOX-4 were administered. Stable disease for a minimum of 9 weeks was observed in 62.5% (10/16) for a mean duration of 19.4 weeks; overall mean time to progression (TTP) as measured by imaging studies was 17.8 weeks (range 2–70 weeks). Reasons for discontinuation of treatment included documented tumor progression in 8 cases (50%) and adverse events in 4 cases (25%) (grade II neurotoxicitiy in 3 cases and grade III neutropenia in 2 cases). 2 patients died during treatment due to tumor progression. 4 patients currently still receive FOLFOX-4 after a mean treatment period of 16 weeks. Side effects according to CTC-NCI-criteria include mild anemia (grade I: n=15), thrombocytopenia (I: n=4, II: n=1), neutropenia (I: n=1, III: n=2), increased serum creatinine (I: n=2), nausea (I: n=4, II: n=4, III: n=1), vomiting (I: n=2, II: n=2), and neurotoxicity (I: n=1, II: n=4). Conclusions: The FOLFOX-4 regimen was well tolerated and effective in progressive malignant NEC with increased proliferative potential. Response may be comparable to current standard regimens. FOLFOX-4 should be evaluated in a prospective controlled clinical trial.

No significant financial relationships to disclose.

Endocrine tumours of the gastrointestinal tract. Management of metastatic endocrine tumours

Gastroenteropancreatic tumours are rare. They compromise a heterogenous class of neoplasm. If there is no hypersecretion syndrome, symptoms may be uncharacteristic and thus diagnosis occurs rather late after the first manifestations of the disease. The most important prognostic parameters are histological classification, the localisation of the primary, the tumour size and stage at diagnosis, and the presence or absence of metachronous or synchronous neoplasia. The article will focus on the importance of each of these parameters for the various treatment options in patients with metastatic disease.

Prevalence of aspirin resistance in patients with type 2 diabetes

Aspirin resistance has been recognised to occur in patients with cardiovascular disease and is associated with poor clinical prognosis. The purpose of the present study was to evaluate the prevalence of aspirin resistance in 172 patients with diabetes mellitus type 2 (DM-2). Platelet function of 172 consecutive patients with type 2 diabetes on chronic aspirin therapy was evaluated. The effect of aspirin was assessed using the platelet function analyser (PFA-100) system, reporting platelet-dependent thrombus formation as the time required to close a small aperture in a biologically active membrane. Resistance to aspirin was defined as a normal collagen/epinephrine-induced closure time (82-165 s). Aspirin responders were defined when closure time was > or =300 s. Thirty-seven (21.5%) of the type 2 diabetic patients were found to be resistant to chronic aspirin therapy, 29 (16.9%) were semi-responders and 106 (61.6%) were responders. Univariate analysis revealed that aspirin non-responders were significantly younger (p<0.05) compared to aspirin responders. A significant number of type 2 diabetic patients are resistant to aspirin therapy. Aspirin resistance can be evaluated by point-of-care testing and should be recognised in diabetic patients that are treated for primary or secondary prevention.

Presurgical octreotide treatment in acromegaly: no improvement of final growth hormone (GH) concentration and pituitary function. A long-term case-control study

BACKGROUND

The effect of presurgical long-acting somatostatin analogue (SSA) treatment on operative outcome in acromegaly is as yet uncertain and long-term observations are lacking. We evaluated in an acromegaly case-control study the effect of octreotide pre-treatment on short- and long-term postoperative GH concentrations, pituitary function and glucose tolerance.

METHODS

48 patients with a pituitary macro-adenoma - micro- and giant adenomas excluded - were evaluated. 24 patients received presurgical octreotide treatment (secondary surgery, prospectively studied). Another 24 thoroughly matched patients had been operated on without prior octreotide therapy (primary surgery, retrospective evaluation). No patient had received any other treatment prior to operation/octreotide. Standardized testing was performed at diagnosis, following octreotide treatment, after surgery and then yearly for 10.3+/-0.9 yrs (mean+/-SE, primary surgery) and 4.1+/-0.6 yrs (secondary surgery). Immediate and 4-year postoperative results were compared. All work-up was strictly identical in both groups, except for imaging techniques. "Partial remission" was defined as mean GH profile (6-h/7-point) concentration <2.5 microg/L, and "complete remission" as GH nadir <1 microg/L during OGTT plus normal IGF-I concentration (when available).

FINDINGS

The median profile GH (microg/L) values and the OGTT GH nadir values post-surgery (2.4/1.0 vs 1.8/0.7, primary and secondary surgery, resp.) as well as 4 yrs later (2.1/1.15 vs 2.3/0.8) were not significantly different between the groups. The 10-year results of the primary surgery group were not significantly different from its 4-year results. Subgroup analysis of pre-treated patients revealed no significant difference between those with and without tumour shrinkage, or between those with and without parasellar tumour extension. Postoperatively pituitary function was not significantly different between the groups. After 4-years the pituitary-adrenal axis was slightly more impaired in the secondary surgery group rather than following primary surgery, while the pituitary-gonadal axis was not different.

CONCLUSION

Presurgical octreotide treatment has no significant short- or long-term beneficial effect on GH concentration or pituitary function.

Value of image fusion using single photon emission computed tomography with integrated low dose computed tomography in comparison with a retrospective voxel-based method in neuroendocrine tumours

The objective was the evaluation of single photon emission computed tomography (SPECT) with integrated low dose computed tomography (CT) in comparison with a retrospective fusion of SPECT and high-resolution CT and a side-by-side analysis for lesion localisation in patients with neuroendocrine tumours. Twenty-seven patients were examined by multidetector CT. Additionally, as part of somatostatin receptor scintigraphy (SRS), an integrated SPECT-CT was performed. SPECT and CT data were fused using software with a registration algorithm based on normalised mutual information. The reliability of the topographic assignment of lesions in SPECT-CT, retrospective fusion and side-by-side analysis was evaluated by two blinded readers. Two patients were not enrolled in the final analysis because of misregistrations in the retrospective fusion. Eighty-seven foci were included in the analysis. For the anatomical assignment of foci, SPECT-CT and retrospective fusion revealed overall accuracies of 91 and 94% (side-by-side analysis 86%). The correct identification of foci as lymph node manifestations (n=25) was more accurate by retrospective fusion (88%) than from SPECT-CT images (76%) or by side-by-side analysis (60%). Both modalities of image fusion appear to be well suited for the localisation of SRS foci and are superior to side-by-side analysis of non-fused images especially concerning lymph node manifestations.

Neuroendokrine Tumoren des Gastrointestinaltrakts

Gastrointestinal neuroendocrine tumours are classified as functioning or non-functioning according to the presence or absence of a clinically evident hypersecretion syndrome. In foregut tumours the presence of autonomous hormone secretion and the respective hypersecretion syndrome indicate functionality. Abdominal ultrasound (US), computed tomography (CT), magnetic resonance tomography (MRT) and somatostatin receptor scintigraphy (SRS) are used for localisation of the primary tumour and metastasis. Invasive procedures such as endoscopic US, intraoperative US or intraoperative duodenal transillumination are useful to localise small (< 1 cm) tumours. For localised tumours surgery is the first line treatment. In metastatic disease symptomatic therapy, biotherapy and chemotherapy are available. Cytoreductive therapy such as embolisation, chemoembolisation, thermo- or cryotherapy, or radio-receptor therapy are additional options. The first symptom of most neuroendocrine midgut tumours is abdominal pain. An increased chromogranin-A plasma concentration or 5-hydroxyindoleacetic acid 24-h urinary excretion indicates the neuroendocrine origin of the tumour or the possibility of a carcinoid syndrome, respectively. Surgical therapy prolongs survival but is rarely curative. Biotherapy is effective as symptomatic therapy. However, its cytoreductive potency is low. Chemotherapy is less effective in midgut tumours compared to foregut tumours. Cytoreductive strategies (chemoembolisation, thermo- or cryotherapy, cytoreductive surgery) and radio-receptor therapy may offer new therapeutic options. However, their definitive value has yet to be defined.

Diagnosis of neuroendocrine tumours by retrospective image fusion: is there a benefit?

This study evaluated the use of image fusion in the preoperative staging of neuroendocrine tumors (NET) of the pancreas and the gastrointestinal tract (GIT). Thirty-eight patients suffering from a metastasized NET with location of the primary in the pancreas ( n=15) or the GIT ( n=23) were examined by somatostatin receptor scintigraphy (SRS) and computed tomography (CT). Consecutive image registration and fusion were performed using custom-built software integrated in AVS/Express (Advanced Visual Systems, Waltham, MA, USA). Registration was performed by a voxel-based algorithm based on normalized mutual information. Image fusion was feasible in 36/38 patients. A total of 87 foci were assigned to anatomical regions (e.g. gut, pancreas, liver, lymph node or others) by two independent observers in both SRS and SRS/CT fusion images. The assignments used a binary ranking system (1="definite", 0="not definite"). These results were then retrospectively compared to the classification of the foci, based on postoperative histology or clinical follow-up. Imaging by SRS allowed a definite anatomical assignment in 57% (50/87) and 61% (53/87) of all lesions in the case of observers A and B, respectively. Image fusion improved the topographic assignment to 91% (79/87) and to 93% (81/87). The number classified as "definite" by both observers increased from 54% (47/87) to 86% (77/87). The increase in definite assignments was highly significant for both observers ( P<0.0001 for each). In the case of foci classified as liver metastases, image fusion allowed improved assignment to the corresponding liver segment from 45% (18/40) to 98% (39/40) and from 58% (23/40) to 100% (40/40) by observers A and B, respectively. Furthermore, the improved assignment of foci classified as lesions by image fusion was relevant for therapy in 7/36 patients (19%). Therefore, the image fusion technique presented herein appears to be a very useful method for clinical routine.

Neuroendocrine tumors of the gastro-entero-pancreatic system: the role of early diagnosis, genetic testing and preventive surgery

Surgery is the only curative approach in neuroendocrine gastro-entero-pancreatic (GEP) tumors. As cure is highly dependent of tumor size, early diagnosis is a prerequisite for surgical success. Diagnosis of nonfunctioning tumors of the pancreas or midgut origin is due to symptoms related to the tumor burden, thus early diagnosis is mostly incidental. Functioning pancreatic tumors should be operated early in the course of the disease to provide cure. No genetic screening is available for sporadic GEP tumors. In patients with MEN-1 syndrome genetic screening is recommended to restrict the burden of clinical screening to those with positive test results. Due to the nature of the disease cure may not be achieved, however prevention of cancer may be obtained for one or two decades of life, especially in patients with gastrinoma or nonfunctioning tumors.

Octreotide suppresses the incretin glucagon-like peptide (7-36) amide in patients with acromegaly or clinically nonfunctioning pituitary tumors and in healthy subjects

OBJECTIVE

To study the effect of octreotide on glucagon-like peptide (7-36) amide (GLP-1) and insulin secretion in patients with pituitary tumors during preoperative treatment and in healthy subjects.

DESIGN

Open design prospective clinical study.

METHODS

Eighteen patients with pituitary macroadenomas (13 clinically nonfunctioning (NFA; 11/13 had GH insufficiency), 5 GH secreting (GHA)) received preoperative octreotide treatment: 3x100 microg/day s. c. for 3 months, and 3x500 microg/day s.c. for an additional 3 months. Seven healthy subjects received (for ethical reasons) only 3x100 microg/day for 10 days. A standardized meal (St-M) test, oral glucose test (oGTT) and i.v. glucose test (ivGTT) were done before octreotide therapy, on days 1, 2 and 3 (D1,2,3), after 3 months (M3) and 6 months (M6) of octreotide treatment in the patients, and before treatment, on D1,2,3 and on D8,9,10 of octreotide treatment in the healthy subjects. Serum GLP-1, insulin and GH as well as plasma glucose were determined for 180 min (oGTT, St-M) or 120 min (ivGTT).

RESULTS

Pretreatment fasting GLP-1 concentrations as well as integrated responses (area under the curve 0-180 min) to oGTT and St-M were not significantly different between NFA, GHA and healthy subjects. During the oGTT, octreotide initially almost abolished the early (0-60 min) and diminished the late (60-180 min) GLP-1 and insulin responses in patients and healthy subjects. At M6 integrated insulin responses had significantly recovered, while the increase in GLP-1 response failed to reach significance (GLP-1: 56.5% of pretreatment at D2 versus 93.5% at M6 and 41.2 versus 63.1% in NFA and GHA respectively; insulin: 50.2 versus 71.2% and 35.5 versus 70. 4%). An escape of GLP-1 and insulin in healthy subjects (D2 versus D9) was not significant. Intestinal glucose absorption was apparently not reduced, since the early glucose rise was similar before and during octreotide treatment. During the St-M the GLP-1 and insulin responses were similarly suppressed by octreotide and recovered during ongoing treatment (GLP-1: 49.6% of pretreatment at D1 versus 79.0% at M6 in NFA and 46.9 versus 52.9% in GHA. Insulin: 27.6 versus 83.9% and 23.5 versus 54.4%). The escape was significant in NFA but not in GHA. In the healthy subjects the escape was already significant on D8 (GLP-1: 39.5% of pretreatment at D1 versus 68.3% at D8; insulin: 36.6 versus 53.8%). During the ivGTT GLP-1 did not increase. The early insulin response (0-30 min) was abolished by octreotide, followed by a reduced peak at 60 min. The reduction of the integrated insulin response during ivGTT was similar to that during oGTT. An insulin escape reached significance only for NFA (52. 6% of pretreatment at D3 versus 66.7% at M6). Glucose tolerance (KG value) deteriorated and did not improve during ongoing treatment. Octreotide suppressed the median GH concentration (8h profile) of the GHA patients from 10.3 microg/l (pretreatment) to 5.8, 6.3 and 3. 7 microg/l at D4, M3 and M6 with no escape. GH was 1.5 microg/l postoperatively.

CONCLUSIONS

Octreotide abolishes the early and diminishes the late GLP-1 and insulin responses to oGTT and St-M in NFA and GHA patients and in healthy subjects. In contrast to GH, both hormones partially escape from suppression during ongoing therapy. During treatment with our conventional octreotide doses suppression of insulin secretion is maximal. Under these conditions an effect of the additional loss of GLP-1 is not apparent. Basal GLP-1 concentrations and integrated responses to oGTT and St-M were similar in healthy subjects and in patients with GH excess or GH insufficiency.

Effect of the somatostatin analog octreotide on gastric mucosal function and histology during 3 months of preoperative treatment in patients with acromegaly

OBJECTIVE

To study the effects of the somatostatin analog octreotide on gastric mucosal function and histology during short-term (3 months) preoperative treatment in patients with acromegaly.

DESIGN

Open design clinical study.

METHODS

10 patients were studied before treatment with octreotide (pre-tx), on day 1 of 300 microg octreotide/day (d300), after 1 week on 300 (w300), 600 (w600) or 1500 (wl500) microg octreotide/day, and after an additional 2.5 months on 1500 microg octreotide/day (M3). An 8h gastrin profile was obtained and ambulatory intragastric 23h pH-metry carried out at the indicated time points. Gastroscopy was performed at pre-tx and M3 and multiple mucosal biopsy specimens taken.

RESULTS

The mean serum gastrin concentration at first declined during octreotide therapy to a nadir at w1500, then recovered despite ongoing therapy (probably in response to reduced gastric acidity) and was similar to pre-tx values at M3 (mean+/-S.E.: 87+/-26, 50+/-11 and 98+/-46ng/l for pre-tx, w1500 and M3 respectively; P<0.05, pre-tx vs w1500). Gastric acidity had also declined at d300(P<0.05, d300 vs pre-tx), then recovered (despite the increase in the octreotide dose), but declined again at M3 (mean pH (95% confidence interval): 2.4 (1.7-3.2), 3.3 (2.4-4.3), 2.6 (1.8-:3.5, n=8) and 2.9 (1.6-4.2, n=7) at pre-tx, d300, w1500 and M3 respectively). The gastrin concentration at M3, although similar to pre-tx values, remained inadequately low for the reduced gastric acidity. The reduction in gastric acidity was marked during the daytime (0900-2200 h; P<0.01, d300 vs pre-tx and P=0.028, M3 vs pre-tx). However, while the stimulated postprandial gastric acid secretion was reduced at d300 (P<0.01, d300 vs pre-tx) and at M3 (n=7; P=0.027, M3 vs pre-tx), fasting and preprandial acidity was not affected. During the night, gastric acidity was reduced from 2200 to 0300 h, but the reduction was less marked than during the daytime. Paradoxically, the physiological intermittent late nocturnal reduction in acidity ('pH peaks' (0300-0800 h)) was abolished rather than enhanced. No patient acquired new Helicobacter pylori infection. The mean gastritis scores for antrum and body (n=8, Sidney classification) increased marginally from 1.7 to 1.9 (chronicity) and from 0.7 to 0.9 (atrophy), while the activity score was slightly reduced from 1.2 to 1.0.

CONCLUSIONS

Three months of preoperative octreotide treatment profoundly and persistently altered gastric mucosal function (gastrin suppression, reduced acidity), but caused only minor variations in the pre-existing gastritis scores.