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1.
Langenbecks Arch Surg ; 408(1): 255, 2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37386194

ABSTRACT

PURPOSE: Most insulinomas are small solitary, benign neoplasms. Imaging and surgical techniques improved over the last 20 years. Thus, the aim of the present study was to analyze changes in diagnosis and surgery of insulinoma patients in a referral center over two decades. METHODS: Operated patients with a histologically proven insulinoma were retrieved from a prospective database. Clinico-pathological characteristics and outcomes were retrospectively analyzed with regard to the time periods 2000-2010 (group 1) and 2011-2020 (group 2). RESULTS: Sixty-one of 202 operated patients with pNEN had an insulinoma, 37 (61%) in group 1 and 24 (39%) in group 2. Of those 61 insulinomas, 49 (80%) were sporadic benign, 8 (13%) benign MEN1-associated insulinomas, and 4 (7%) sporadic malignant insulinomas. In 35 of 37 (95%) patients of group 1 and all patients of group 2, the insulinoma was preoperatively identified by imaging. The most sensitive imaging modality was endoscopic ultrasound (EUS) with correctly diagnosed and localized insulinomas in 89% of patients in group 1 and 100% in group 2. In group 1, significantly less patients were operated via minimally invasive approach compared to group 2 (19% (7/37) vs. 50% (12/24), p = 0.022). Enucleation was the most frequently performed operation (31 of 61, 51%), followed by distal resection (15 of 61, 25%) without significant differences between groups 1 and 2. The rate of relevant postoperative complications was not different between groups 1 and 2 (24% vs. 21%, p = 0.99). Two patients with benign insulinoma (1 out of each group) experienced disease recurrence and underwent a second resection. After a median follow-up of 134 (1-249) months, however, all 57 (100%) patients with benign insulinoma and 3 out of 4 patients with malignant insulinoma had no evidence of disease. CONCLUSION: Insulinoma can be preoperatively localized in almost all patients, allowing for a minimally invasive, parenchyma-sparing resection in selected patients. The long-term cure rate is excellent.


Subject(s)
Insulinoma , Pancreatic Neoplasms , Humans , Insulinoma/diagnostic imaging , Insulinoma/surgery , Retrospective Studies , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/surgery , Databases, Factual , Endosonography
3.
Ann Surg Oncol ; 29(9): 5568-5577, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35583694

ABSTRACT

BACKGROUND: Surgery with radical intent is the only potentially curative option for entero-pancreatic neuroendocrine tumors (EP-NETs) but many patients develop recurrence even after many years. The subset of patients at high risk of disease recurrence has not been clearly defined to date. OBJECTIVE: The aim of this retrospective study was to define, in a series of completely resected EP-NETs, the recurrence-free survival (RFS) rate and a risk score for disease recurrence. PATIENTS AND METHODS: This was a multicenter retrospective analysis of sporadic pancreatic NETs (PanNETs) or small intestine NETs (SiNETs) [G1/G2] that underwent R0/R1 surgery (years 2000-2016) with at least a 24-month follow-up. Survival analysis was performed using the Kaplan-Meier method and risk factor analysis was performed using the Cox regression model. RESULTS: Overall, 441 patients (224 PanNETs and 217 SiNETs) were included, with a median Ki67 of 2% in tumor tissue and 8.2% stage IV disease. Median RFS was 101 months (5-year rate 67.9%). The derived prognostic score defined by multivariable analysis included prognostic parameters, such as TNM stage, lymph node ratio, margin status, and grading. The score distinguished three risk categories with a significantly different RFS (p < 0.01). CONCLUSIONS: Approximately 30% of patients with EP-NETs recurred within 5 years after radical surgery. Risk factors for recurrence were disease stage, lymph node ratio, margin status, and grading. The definition of risk categories may help in selecting patients who might benefit from adjuvant treatments and more intensive follow-up programs.


Subject(s)
Neuroendocrine Tumors , Pancreatic Neoplasms , Humans , Neoplasm Recurrence, Local/pathology , Neuroendocrine Tumors/pathology , Pancreatic Neoplasms/pathology , Prognosis , Retrospective Studies , Risk Factors , Survival Rate
4.
Internist (Berl) ; 60(3): 247-256, 2019 03.
Article in German | MEDLINE | ID: mdl-30623195

ABSTRACT

The number of cases diagnosed as pancreatic neuroendocrine neoplasia (pNEN) is steadily increasing. The 2017 World Health Organization classification defines a new subgroup of morphologically well differentiated tumors with an elevated proliferation rate (Ki-67 over 20%) as neuroendocrine tumor (NET) G3. Due to the heterogeneity of pNEN regarding etiology (sporadic versus hereditary), symptoms (hormone syndrome versus non-functional tumor), and prognosis (ranging from benign behavior to highly malignant), multidisciplinary management by experienced physicians is required. This is especially true as the number of therapeutic options has increased, while we still lack comparative trials. This overview aims to summarize the multidisciplinary therapeutic options, their selection criteria and the recommendations of the new German S2k guideline.


Subject(s)
Neuroendocrine Tumors , Pancreatic Neoplasms , Humans , Neuroendocrine Tumors/therapy , Pancreatic Neoplasms/therapy , Prognosis
5.
Pancreatology ; 17(1): 139-145, 2017.
Article in English | MEDLINE | ID: mdl-28027897

ABSTRACT

BACKGROUND: Chemotherapy with 5-FU and Streptozotocin (STZ) is recommended as first-line treatment in patients with metastatic pancreatic neuroendocrine neoplasms (PNEN). However, data about biomarkers involved in the 5-FU metabolism to predict response are still limited. OBJECTIVES: Evaluation of clinicopathological features and potential predictive and prognostic markers of patients with PNEN treated with 5-FU based regimens. PATIENTS AND METHODS: We retrospectively analyzed 41 patients with PNEN who were treated at the University Hospital Marburg between 2000 and 2013. Dihydropyrimidine-Dehydrogenase (DPD) and Thymidylate-Synthase (TS) expression was correlated with treatment response in 19 patients who had available tumour tissue and response data. The median overall survival (OS) and progression free survival (PFS) were calculated using Kaplan-Meier and Cox regression methods, respectively. RESULTS: The median PFS in patients receiving 5-FU/STZ was 17 months with a median OS of 50 months. Objective response rate (ORR) and disease control rate (DCR) were 32% and 73%, respectively. Biochemical response (p = 0.005) and high DPD expression (p = 0.018) were predictive markers of response to 5-FU-based chemotherapy. Univariate analysis identified Ki-67 > 10%, no biochemical response, positive 5-HIAA levels and TS deficiency as independent risk factors for shorter PFS. Moreover, performance status (PS) ≥1 was an independent risk factors for impaired OS. CONCLUSIONS: DPD expression and biochemical response represent promising predictive biomarkers for response to 5-FU based chemotherapy. Moreover, Ki-67, PS and TS are independent prognostic markers of OS and PFS in patients with PNEN.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Dihydrouracil Dehydrogenase (NADP)/metabolism , Fluorouracil/therapeutic use , Neuroendocrine Tumors/drug therapy , Pancreatic Neoplasms/drug therapy , Thymidylate Synthase/metabolism , Adult , Aged , Biomarkers, Tumor/metabolism , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neuroendocrine Tumors/enzymology , Neuroendocrine Tumors/mortality , Pancreatic Neoplasms/enzymology , Pancreatic Neoplasms/mortality , Prognosis , Retrospective Studies , Survival Analysis , Treatment Outcome
6.
Horm Metab Res ; 48(9): 575-80, 2016 09.
Article in English | MEDLINE | ID: mdl-27101094

ABSTRACT

Sunitinib treatment leads to improvement in progression-free survival in patients with advanced pancreatic neuroendocrine tumours (pNETs). However, limited data exist regarding the effectiveness, safety and tolerability in clinical practice. We present the results of the first detailed pNET cohort analysis since sunitinib was approved. Patients with advanced, differentiated pNET treated with sunitinib were retrospectively analysed. All patients had progressive disease before start of sunitinib treatment. Twenty-one patients, with a median age of 64 years (range 28-78), were included in this study. Nineteen patients could be analysed for treatment effectiveness. Twelve (57%) patients exhibited either a partial response (1 patient) or stable disease (11 patients) according to the RECIST criteria. The median progression-free survival was 7.0 months (95% CI 3.0-12.0); the probability of being event-free at 6 months was 52.6% (95% CI 28.4-72.1). Potential influencing factors as Ki-67 index, age or duration of disease did not show significant correlations with the response to sunitinib therapy. Considering the differences in patients' characteristics, sunitinib in daily practice showed effectiveness parameters similar to the phase III trial.


Subject(s)
Antineoplastic Agents/therapeutic use , Indoles/therapeutic use , Neuroendocrine Tumors/drug therapy , Pancreatic Neoplasms/drug therapy , Practice Patterns, Physicians' , Pyrroles/therapeutic use , Adult , Aged , Female , Follow-Up Studies , Humans , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Staging , Neuroendocrine Tumors/secondary , Pancreatic Neoplasms/pathology , Retrospective Studies , Sunitinib , Treatment Outcome
7.
Pneumologie ; 70(2): 123-9, 2016 Feb.
Article in German | MEDLINE | ID: mdl-26894394

ABSTRACT

Multifocal neuroendocrine lung tumour is a rare diagnosis. Multiple lung foci of different sizes are usually apparent on chest CT scans. It is assumed that multifocal neuroendocrine lung tumours originally develop from diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH). This results in cell aggregations formed by proliferation of neuroendocrine cells that are already physiologically present in the bronchial system. If these cell proliferations break through the bronchial basement membrane, they are considered to constitute tumourlets if they measure ≤ 5 mm and carcinoid tumours if they are larger than 5 mm. The speed of proliferation of the cell hyperplasias appears to vary. Many of the patients are completely asymptomatic, the multifocal neuroendocrine lung tumours being diagnosed by chance. However, other patients complain of breathlessness, reduced physical capacity and cough. There may also be reduction of lung function. In these cases, chest HRCT often reveals peribronchial fibrosis or bronchiectasis in addition to the lung foci. Bronchoscopy is usually not helpful. Surgical lung biopsy is considered to be the diagnostic gold standard. Histological examination typically shows a mixture of cell hyperplasias, tumourlets and carcinoid tumours. There is no consensus on the treatment of multifocal neuroendocrine tumours. Taking the clinical situation and the chest HRCT findings as our starting point, we developed a stepwise approach that is guided by the success of the individual therapeutic procedures. The most favourable prognosis is found in affected people without clinical symptoms whose lung foci all measure less than 5 mm. In these cases the 5-year survival rate is over 90%.


Subject(s)
Lung Neoplasms/diagnosis , Lung Neoplasms/therapy , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/therapy , Diagnosis, Differential , Evidence-Based Medicine , Humans , Lung Neoplasms/pathology , Neoplasms, Multiple Primary , Neuroendocrine Tumors/pathology , Radiography, Thoracic/methods , Tomography, X-Ray Computed/methods , Treatment Outcome
8.
Geophys Res Lett ; 43(10): 5450-5459, 2016 May 28.
Article in English | MEDLINE | ID: mdl-32753770

ABSTRACT

Cloud observations from the CloudSat and CALIPSO satellites helped to explain the reduced total cloud cover (Ctot) in the atmospheric regional climate model HIRHAM5 with modified cloud physics. Arctic climate conditions are found to be better reproduced with (1) a more efficient Bergeron-Findeisen process and (2) more generalized subgrid-scale variability of total water content. As a result, the annual cycle of Ctot is improved over sea ice, associated with an almost 14% smaller area average than in the control simulation. The modified cloud scheme reduces the Ctot bias with respect to the satellite observations. Except for autumn, the cloud reduction over sea ice improves low-level temperature profiles compared to drifting station data. The HIRHAM5 sensitivity study highlights the need for improving accuracy of low-level (< 700m) cloud observations, as these clouds exert a strong impact on the near-surface climate.

9.
Endocr Relat Cancer ; 22(4): 657-64, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26113608

ABSTRACT

Data on gastroenteropancreatic neuroendocrine neoplasms (NEN) G3 (well-differentiated neuroendocrine tumors (NET G3) and neuroendocrine carcinoma (NEC)) are limited. We retrospectively study patients with NET G3 and NEC from eight European centers. Data examined included clinical and pathological characteristics at diagnosis, therapies and outcomes. Two hundred and four patients were analyzed (37 NET G3 and 167 NEC). Median age was 64 (21-89) years. Tumor origin included pancreas (32%) and colon-rectum (27%). The primary tumor was resected in 82 (40%) patients. Metastatic disease was evident at diagnosis in 88% (liver metastases: 67%). Median Ki-67 index was 70% (30% in NET G3 and 80% in NEC; P<0.001). Median overall survival (OS) for all patients was 23 (95% CI: 18-28) months and significantly higher in NET G3 (99 vs 17 months in NEC; HR=8.3; P<0.001). Platinum-etoposide first line chemotherapy was administered in 113 (68%) NEC and 12 (32%) NET G3 patients. Disease control rate and progression free survival (PFS) were significantly higher in NEC compared to NET G3 (P<0.05), whereas OS was significantly longer in NET G3 (P=0.003). Second- and third-line therapies (mainly FOLFIRI and FOLFOX) were given in 79 and 39 of NEC patients; median PFS and OS were 3.0 and 7.6 months respectively after second-line and 2.5 and 6.2 months after third-line chemotherapy. In conclusion, NET G3 and NEC are characterized by significant differences in Ki-67 index and outcomes. While platinum-based chemotherapy is effective in NEC, it seems to have limited value in NET G3.


Subject(s)
Neuroendocrine Tumors , Pancreatic Neoplasms , Adult , Aged , Aged, 80 and over , Antineoplastic Agents, Phytogenic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Camptothecin/analogs & derivatives , Camptothecin/therapeutic use , Etoposide/therapeutic use , Female , Fluorouracil/therapeutic use , Humans , Ki-67 Antigen/metabolism , Leucovorin/therapeutic use , Male , Middle Aged , Neuroendocrine Tumors/drug therapy , Neuroendocrine Tumors/metabolism , Organoplatinum Compounds/therapeutic use , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Prognosis , Survival Analysis , Young Adult
10.
Pathologe ; 36(3): 261-70, 2015 May.
Article in German | MEDLINE | ID: mdl-25986886

ABSTRACT

Neuroendocrine neoplasms (NEN) of the breast are specific tumor entities. According to the literature up to 5% of breast neoplasms are malignant epithelial neoplasms of the breast. They are defined by a neuroendocrine (NE) architecture and cytology combined with an expression of the neuroendocrine vesicle markers chromogranin A and/or synaptophysin. The diagnosis is supplemented by the receptor status and the proliferative activity. According to the World Health Organization (WHO) classification of 2012 the following groups of NEN are distinguished: (1) invasive breast carcinoma with NE differentiation, (2) well-differentiated neuroendocrine tumor (NET) and (3) poorly differentiated small cell carcinoma (NEC). This review article focuses on (1) the definition and basic principles of diagnostics, (2) the history, nomenclature and WHO classification from 2003 and 2012, (3) the frequency of breast NEN, (4) the hereditary background and functional activity, (5) the expression of receptors and (6) the possible clinical implications. In addition, the first results of a retrospective single center study (n = 465 patients with breast cancer over a time period of 4 years) on the frequency of NEN of the breast at the Breast Center of the University Hospital Düsseldorf are presented. In this study a frequency of 4.5% of NEN was found based on a diagnostic cut-off of > 50% Chromogranin A and/or synaptophysin positive tumor cells.


Subject(s)
Breast Neoplasms/pathology , Neuroendocrine Tumors/pathology , Biomarkers, Tumor/analysis , Breast/pathology , Cell Proliferation , Chromogranin A/analysis , Female , Humans , Neoplasm Invasiveness , Prognosis , Synaptophysin/analysis
11.
Digestion ; 90(2): 89-97, 2014.
Article in English | MEDLINE | ID: mdl-25196446

ABSTRACT

BACKGROUND: Resection with curative intention is the cornerstone of treatment in patients with neuroendocrine tumors. A proportion of patients will relapse after R0 resection, but the factors predictive of recurrence are not well understood. METHODS: A database established 1998 at the University Hospital Marburg was queried for all patients with documented R0 resection. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Uni- and multivariate analyses were performed. RESULTS: 180 patients with a median age of 52 years entered the analysis. We observed 77 recurrences after a median time of 2.9 years. 24% of the recurrences occurred later than 5 years after operation. Median recurrence-free survival of the whole cohort was 101 months. In univariate analysis grade by Ki-67, stage, high lymph node ratio and microangioinvasion were significant predictors of recurrence. On multivariate analysis these parameters were confirmed as independent prognostic parameters with stage and microangioinvasion being the most important predictors. CONCLUSIONS: After R0 resection of neuroendocrine tumors, postoperative surveillance should be extended to at least 10 years. Patients with distant metastases and microangioinvasion are at high risk of recurrence. Clinical trials of adjuvant treatment protocols are indicated in these patients.


Subject(s)
Neoplasm Recurrence, Local/epidemiology , Neuroendocrine Tumors/surgery , Adult , Aged , Aged, 80 and over , Disease-Free Survival , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/therapy , Neuroendocrine Tumors/mortality , Neuroendocrine Tumors/secondary , Prognosis , Treatment Outcome , Young Adult
12.
Pathologe ; 35(3): 283-93; quiz 294, 2014 May.
Article in German | MEDLINE | ID: mdl-24671468

ABSTRACT

Neuroendocrine neoplasms (NEN) of the distal jejunum and ileum derive from serotonin-producing enterochromaffin (EC) cells. Due to their low proliferation rate and their infiltrative growth, they are often discovered at an advanced disease stage when metastasis has already occurred. The biology of these tumours is different from other NEN of the digestive tract. In order to standardise and improve diagnosis and therapy, the guidelines for the diagnosis and clinical management of jejuno-ileal NEN as well as for the management of patients with liver and other distant metastases from NEN were revised by the European Neuroendocrine Tumour Society (ENETS) in 2012. This review focuses on aspects relevant for surgical pathology.


Subject(s)
Ileal Neoplasms/pathology , Jejunal Neoplasms/pathology , Neuroendocrine Tumors/pathology , Cell Proliferation , Diagnosis, Differential , Disease Progression , Enterochromaffin Cells/pathology , Humans , Ileal Neoplasms/surgery , Ileum/pathology , Ileum/surgery , Jejunal Neoplasms/surgery , Jejunum/pathology , Jejunum/surgery , Neuroendocrine Tumors/surgery , Practice Guidelines as Topic , Receptors, Somatostatin/analysis
13.
Internist (Berl) ; 55(2): 206-11, 2014 Feb.
Article in German | MEDLINE | ID: mdl-24449139

ABSTRACT

A 59-year-old patient was admitted to hospital with recurrent flush symptoms and pathologically elevated 5-hydroxyindoleacetic acid (5-HIAA) levels in urine. A known cystic lesion of the liver which had been followed for years by ultrasound examinations and was regarded as a bland hepatic cyst was identified as a metastasis of a neuroendocrine neoplasm of the ileum. In two sequential surgical interventions the primary tumor with mesenteric lymph node metastases as well as the cystic liver metastasis could be resected. After surgical treatment an R1 situation at the mesenteric site and suspicious para-aortic lymph nodes remained. The long established treatment of factor-V Leiden mutation by anticoagulation with phenprocoumon was supplemented by deep subcutaneous injection of lanreotide autogel every 4 weeks. Currently, there is no evidence for progressive disease and the patient is without clinical signs of a carcinoid syndrome.


Subject(s)
Cysts/diagnosis , Cysts/prevention & control , Flushing/diagnosis , Flushing/prevention & control , Liver Neoplasms/diagnosis , Liver Neoplasms/therapy , Malignant Carcinoid Syndrome/diagnosis , Malignant Carcinoid Syndrome/therapy , Cysts/complications , Diagnosis, Differential , Flushing/etiology , Humans , Liver Neoplasms/complications , Male , Malignant Carcinoid Syndrome/complications , Middle Aged
14.
Zentralbl Chir ; 139(3): 276-83, 2014 Jun.
Article in German | MEDLINE | ID: mdl-23042103

ABSTRACT

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.


Subject(s)
Digestive System Neoplasms/diagnosis , Digestive System Neoplasms/surgery , Hormones, Ectopic/blood , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/surgery , Registries , Adolescent , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Digestive System Neoplasms/pathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Grading , Neuroendocrine Tumors/pathology , Prognosis , Syndrome , Young Adult
15.
Internist (Berl) ; 53(4): 400-7, 2012 Apr.
Article in German | MEDLINE | ID: mdl-22388921

ABSTRACT

Multiple endocrine neoplasia type 1 (MEN-1) is an autosomal-dominant hereditary disease characterized by the occurrence of tumors of the parathyroids, duodenum and/or pancreas, and anterior pituitary. The syndrome is caused by germline mutations of the MEN1 tumor suppressor gene. The identification of the causative mutations is of paramount importance for the long-term management of affected individuals and their relatives. Multiple endocrine neoplasia type 2 (MEN2) is less frequent than MEN1 and represents a cancer syndrome caused by autosomal-dominant inherited mutations of the RET proto-oncogene, and displays a genotype-phenotype correlation of remarkable clinical relevance. Major components of MEN-2 comprise medullary thyroid carcinoma (MTC), pheochromocytoma, and primary hyperparathyroidism. Since 25-30% of patients with MTC display a hereditary background, genetic testing is indicated once MTC is diagnosed. Occurrence of MTC can be avoided by prophylactic thyroidectomy in early childhood in gene carriers. Early diagnosis and therapy of simultaneous pheochromocytoma avoids the development of complications caused by acute or chronic hypertension.


Subject(s)
Genetic Predisposition to Disease/genetics , Genetic Predisposition to Disease/prevention & control , Genetic Testing/methods , Multiple Endocrine Neoplasia Type 1/diagnosis , Multiple Endocrine Neoplasia Type 1/genetics , Multiple Endocrine Neoplasia Type 2a/diagnosis , Multiple Endocrine Neoplasia Type 2a/genetics , Humans , Multiple Endocrine Neoplasia Type 1/therapy , Multiple Endocrine Neoplasia Type 2a/therapy , Polymorphism, Single Nucleotide/genetics , Proto-Oncogene Mas
16.
Best Pract Res Clin Gastroenterol ; 19(4): 649-56, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16183533

ABSTRACT

Malignant neuroendocrine tumours are less sensitive to chemotherapy than other epithelial malignancies. If chemotherapy is considered, tumours of pancreatic origin have a higher sensitivity than tumours from the gastrointestinal tract ('carcinoids'). Chemotherapy with streptozocin combinations and with dacarbazine should be considered in patients with progressive malignant neuroendocrine tumours of the pancreas. A favourable response to chemotherapy can be expected in up to 60% of patients receiving a combination of streptozocin plus doxorubicin, and in up to 40% of patients receiving dacarbazine. A survival benefit has been shown for streptozocin combinations. Treatment regimens are effective in functioning and non-functioning tumours. The response to treatment cannot be predicted. Poorly differentiated neuroendocrine tumours, independent of their origin, respond to a combination of etoposide plus cisplatin. Chemotherapy is, however, almost ineffective in patients with well-differentiated neuroendocrine tumours originating in the gastrointestinal tract ('carcinoids').


Subject(s)
Antibiotics, Antineoplastic/therapeutic use , Carcinoma, Neuroendocrine/drug therapy , Pancreatic Neoplasms/drug therapy , Streptozocin/therapeutic use , Antineoplastic Agents, Alkylating/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Neuroendocrine/pathology , Cell Differentiation , Dacarbazine/therapeutic use , Disease Progression , Gastrointestinal Neoplasms/drug therapy , Humans , Pancreatic Neoplasms/pathology
17.
Exp Eye Res ; 68(4): 493-504, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10192807

ABSTRACT

Previous studies have shown that treatment of guinea pigs with hyperbaric oxygen (HBO) produces certain changes in the lens nuclei of the animals which are typical of those occurring during aging. These include an increase in nuclear light scattering (NLS), elevation in levels of oxidized thiols, loss of water-soluble protein and damage to nuclear membranes. The present study investigated the effect of HBO-treatment in vivo on lens cytoskeletal proteins and MIP26 which are also known to undergo alteration with age. Young (2-month-old) and old (18-month-old) guinea pigs were treated 15 and 30 times with HBO (3 times per week with 2.5 atmospheres of 100% oxygen for 2.5 hr periods). SDS-PAGE and Western blotting showed that HBO-treatment of the older animals accelerated the age-related loss of five nuclear cytoskeletal proteins including actin, vimentin, ankyrin, alpha-actinin and tubulin, compared to levels present in age-matched controls (effects on spectrin and the beaded filaments were not investigated in this study). Treatment of the young animals with HBO produced losses which were primarily associated with concentrations of the nuclear alpha- and beta-tubulins; these cytoskeletal proteins were observed to be most sensitive to the induced oxidative stress, and were affected earliest in the study. Disulfide-crosslinking, rather than proteolysis, appeared to be the main cause of the HBO-induced cytoskeletal protein loss (elevated levels of calcium, which might have induced proteolysis, were not found in the experimental nuclei). Loss of MIP26 was observed only in the older guinea pigs treated 30 times with HBO; both disulfide-crosslinking and degradation to MIP22 were associated with the disappearance. Thus, nuclear MIP26 was susceptible to oxidative stress, but less so than the cytoskeletal proteins, particularly the tubulins. No cortical effects on either MIP26 or the cytoskeletal proteins were observed under any of the treatment protocols. No direct link was observed between an HBO-induced increase in NLS (observed in both the young and old animals using slit-lamp biomicroscopy) and losses of either MIP26 or the cytoskeletal proteins. The appearance of HBO-induced nuclear opacity without any change in the levels of nuclear sodium, potassium or calcium is similar to that observed previously for human senile pure nuclear cataracts. The results provide additional evidence that molecular oxygen can enter the nucleus of the lens and promote age-related events. The observed effects on MIP26 and the cytoskeletal proteins are indicative of an increased level of lens nuclear oxidative stress in the HBO model, possibly a precursor to nuclear cataract.


Subject(s)
Aging/metabolism , Cataract/etiology , Cytoskeletal Proteins/metabolism , Eye Proteins/metabolism , Hyperbaric Oxygenation/adverse effects , Lens Nucleus, Crystalline/metabolism , Membrane Glycoproteins , Animals , Aquaporins , Calcium/metabolism , Crystallins/metabolism , Electrophoresis, Polyacrylamide Gel , Guinea Pigs , Models, Biological , Potassium/metabolism , Sodium/metabolism , Tubulin/metabolism , Vimentin/metabolism
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