Current practice in approaching controversial diagnostic and therapeutic topics in gastroenteropancreatic neuroendocrine neoplasm management. Belgian multidisciplinary expert discussion based on a modified Delphi method.

BACKGROUND AND STUDY AIMS: Neuroendocrine neoplasms (NENs) are relatively rare, with marked clinical and biological heterogeneity. Consequently, many controversial areas remain in diagnosis and optimal treatment stratification for NEN patients. We wanted to describe current clinical practice regarding controversial NEN topics and stimulate critical thinking and mutual learning among a Belgian multidisciplinary expert panel. PATIENTS AND METHODS: A 3-round, Delphi method based project, coordinated by a steering committee (SC), was applied to a predefined multidisciplinary NEN expert panel studying the following controversial topics : factors guiding therapeutic decision making, the use of somatostatin analogues (SSA) in adjuvant setting, the interference between non-radioactive and radioactive SSAs, challenging small intestine neuroendocrine tumor (NET) cases, the approach of the carcinoid syndrome, the role of chemotherapy in well differentiated NET, the relevance of NET G3 and neuroendocrine carcinoma subclassification and the role of imaging techniques in NEN management. RESULTS: A high level of consensus exists regarding the necessary diagnostic work-up, use of imaging techniques and interference between non-radioactive and radioactive SSAs. However, the prognostic impact of tumor functionality might be overrated and adequate diarrhea differential diagnostic work-up in these patients is underused. Significant differences are seen between individual experts and centers regarding treatment preferences both on the treatment modality level, as well as the choice of specific drugs (e.g. chemotherapy regimen). CONCLUSIONS: A Delphi-like multi-round expert discussion proves useful to boost critical thinking and discussion among experts of different background, as well as to describe current clinical practice and stimulate mutual learning in the absence of high-level scientific guidance.

Biofilters to treat the pesticides wastes from spraying applications: results after 4 years of study.

Biofilters were developed in order to eliminate or reduce the quantity of pesticides from rinsing and cleaning waters of sprayers. Biofilters consist in 1, 2 or 3 plastic containers of 1 m3 placed in a vertical pile and containing a substrate elaborated from a homogenised mixture of local soil, chopped straw and compost able to absorb and degrade the pesticides. Biofilters are installed near the area for cleaning and rinsing the sprayer and the waste waters are pumped into the system. Since 2002, a pilot study is carried out in Belgium in order to evaluate the efficacy of these systems. Twenty pilot systems were installed since 2002 until 2004 in several farms, agricultural technical centres or schools and in a municipal maintenance service. The efficacy of the biofilters was studied for several chemical classes of herbicides (sulfonylurea, aryloxyalcanoic acids, chloroacetanilides), insecticides (pyrethroids, carbamates) and fungicides (dicarboximides, phenylamides, triazoles and strobilurines). The balance of the inputs and the outputs of the pesticides was determined by monitoring the elutes. The degradation kinetic of pesticides into the substrate was evaluated by analysing the pesticides into the substrate. The microbiological activity of the substrate was also evaluated by measuring respiration and some indirect parameters like dry matter content, Kjeldahl nitrogen content, organic carbon content and biological oxygen demand (BOD). Results obtained until now after four years of experiments have showed an overall good efficacy (retention) of pesticides by the biofilter and a high degradation rate for the majority of pesticides. Biofilters permit to reduce highly the quantity of pesticides from rinsing and cleaning waters of sprayers and contribute significantly to the reduction of the contamination of surface water. Biofilters are now registered by the Ministry of Agriculture and Environment of the Walloon Region in Belgium and are recommended to pesticides users.

Development of biofilters to treat the pesticides wastes from spraying applications.

Several studies carried out in Europe showed the importance of direct losses to the contamination of surface water by pesticides. These pesticides losses can occur at the farm site when the sprayer equipment is filled with the pesticide formulation (spills, overflowing, leaking) and during the clean-up (rinsing) of the sprayer after the treatment. In Belgium studies are carried out on biofilters to treat in an efficient way effluents containing pesticides. The biofilter substrate is elaborated from a homogenised mixture of local soil, chopped straw and peat or composted material, able to absorb or degrade the active substances. Biofilters consist in systems of 2 or 3 units depending on the spray equipment of the farmer and on the configuration of the farmyard. Each unit is made from a 1 m3 plastic container and the different units are stacked in a vertical pile and connected between them using plastic valves and pipes. Eight pilot systems were installed in March 2002 in seven farms and in one agricultural school, all selected in the loamy region of Belgium specialised in arable crops such as cereals, sugar beets and vegetables. The efficacy (yield) of the systems was determined by measuring the balance of the inputs and outputs of the pesticides. Results were expressed in percent of pesticide retained on the biofilters. The results obtained after two years with 5 tracer pesticides (atrazine, carbofuran, diuron, lenacil and simazine) brought on the biofilter installations are very satisfactory since the percentage of retention is generally higher than 95% of the amount applied. In the beginning of 2004, ten new pilot biofilters were installed in several farms or agricultural technical centres (producing cereals, sugar beets, potatoes, vegetables, fruits or ornamental plants), and in a municipal maintenance service. Some biofilters were installed in duplicate in order to compare the efficacy of different substrates. The efficacy of the biofilters was studied for the 5 classical tracer pesticides but also for other chemical classes of herbicides (sulfonylurea, aryloxyalcanoic acids, chloroacetanilides), insecticides (pyrethroids, carbamates) and fungicides (dicarboximides, phenylamides, triazoles and strobilurines). To monitor these pesticides in elutes and substrates, two analytical methods were developed, optimised and validated : the first one by Gas Chromatography with Mass Spectrometry Detection (GC-MS), and the second one by High Performance Liquid Chromatography with UV Diode Array Detection (HPLC-DAD). The micro-organisms activity in the substrate was also measured in some situations.