Introduction. L’efficacité de la chimiothérapie intracavitaire dépend de la pénétration du produit au sein du péritoine (CHIP) ou de la plèvre. L’hyperthermie et l’hyperpression peuvent augmenter cette pénétration. Ce travail étudie leur effet intrapéritonéal, puis établit la méthode optimale pour les délivrer. L’étude de la faisabilité et de la tolérance d’une hyperpression intrapleurale est essentielle pour transposer ces bénéfices à la cavité thoracique. Méthodes. Quatre groupes de porcs ont reçu une CHIP ouverte avec de l’oxaliplatine à une concentration constante (150 mg/l) pendant 30 minutes en normothermie ou hyperthermie (42-43°C) ; et en pression atmosphérique ou hyperpression (25 cmH2O). Deux groupes ont reçu une procédure fermée en hyperthermie et hyperpression ou forte hyperpression (40 cmH2O). L’absorption systémique et tissulaire d’oxaliplatine a été étudiée. La tolérance d’une perfusion pleurale a été étudiée chez 21 porcs avec ou sans résection associée, avec ou sans chimiothérapie (cisplatine + gemcitabine), à divers niveaux de pression de 15 à 25 cmH2O. Résultats. L’hyperthermie augmente les concentrations de platine dans les surfaces viscérales (p=0.0014), alors que l’hyperpression l’augmente dans les surfaces viscérales et pariétales (respectivement p= 0.0058 et p= 0.0044). L’association des deux facteurs permet d’obtenir les concentrations les plus importantes dans le péritoine viscéral (p= 0.00001) et pariétal (p= 0.0003). Les concentrations obtenues lors des procédures fermées sont inférieures à celles obtenues en ouvert, même lorsque la pression atteint 40 cmH2O. Une chimiothérapie intrapleurale à 20 cmH2O sans résection associée est le niveau maximal toléré durant 60 minutes. Conclusion. Au cours d’une CHIP, l’hyperthermie augmente la pénétration d’oxaliplatine dans le péritoine viscéral, alors que l’hyperpression est efficace dans le péritoine viscéral et pariétal. Leur association est synergique et la procédure ouverte semble la meilleure pour la délivrer. Une chimiothérapie intrapleurale est faisable à 20 cmH2O dans ce modèle. / Introduction. In order to achieve a good effect, chemotherapy drugs need to penetrate into the peritoneal (HIPEC) or pleural tissue. Hyperthermia and high-pressure may enhance this penetration. The aim of this study was to evaluate their peritoneal effect and to establish the best technique to it. A feasibility study of an intrapleural high-pressure was an essential step to export these effects to the thoracic space. Methods. Four groups of pigs underwent an open HIPEC with a constant concentration (150 mg/l) of oxaliplatin during 30 minutes either in normothermia, or in hyperthermia (42-43°C); and either with atmospheric pressure or with high-pressure (25 cmH2O). Two more groups underwent a closed procedure with hyperthermia and either high-pressure or very high-pressure (40 cmH2O). The systemic and tissue absorption of oxaliplatin were studied. The haemodynamic and respiratory tolerance of a pleural infusion was also tested in 21 pigs with and without associated resection; with and without chemotherapy infusion (cisplatin + gemcitabin) and at various levels of pressure (from 15 to 25 cmH2O). Results. Hyperthermia enhances the concentrations of platinum in visceral surfaces (p=0.0014), whereas high-pressure enhances it both in visceral and in parietal surfaces (p= 0.0058 and p= 0.0044, respectively). Their association obtains the highest concentrations both in the visceral (p= 0.00001) and the parietal peritoneum (p= 0.0003). The concentrations obtained during closed procedure are lower than those achieved with the open technique, even with 40 cmH2O of pressure. A 60-minutes intrapleural chemotherapy perfusion with 20 cmH2O of pressure without any lung resection was the maximal tolerated level. Conclusion. During HIPEC, hyperthermia improves the penetration of oxaliplatin in the visceral peritoneum, whereas high-pressure is effective in both peritoneal surfaces. Their association is synergic and the open technique seems to be the best one to deliver it. An intrapleural chemotherapy with a 20 cmH2O pressure is feasible in this model.

For more than a decade, community groups, scientific organizations and government agencies have collaborated to repopulate the endangered western barred bandicoot (Perameles bougainville). While initially successful, the unexpected discovery of a papillomatosis and carcinomatosis syndrome in captive and wild populations of P. bougainville exposed a dearth of knowledge regarding their diseases. This dissertation addresses this issue through study of the clinical pathology, immunology, parasitology, and virology of P. bougainville. To facilitate the detection and understanding of diseases in P. bougainville, guidelines for interpreting haematology and clinical chemistry results were developed, including calculated species-specific reference intervals for plasma aspartate transaminase activity (20–283 U/L), haemoglobin (122-165 g/L), haematocrit (0.36-0.49 L/L), total leukocytes (2.9-14.9 x10^9/L), monocytes (0-0.6 x10^9/L), eosinophils (0-0.9 x10^9/L) and total protein (47-63 g/L) estimated by refractometry. P. bougainville immunoglobulin was also fractionated from plasma and inoculated into sheep to derive antiserum for serological screening assays. Arthropods, helminths and protozoa parasitic on P. bougainville were catalogued and Eimeria kanyana n. sp. was formally described. The pathogenic and zoonotic potential of bacteria detected in ticks parasitic on P. bougainville was also considered. The association between bandicoot papillomatosis carcinomatosis virus type 1 (BPCV1) and the western barred bandicoot papillomatosis and carcinomatosis syndrome was investigated using PCR, in situ hybridization and virus isolation. Optimized in situ hybridization techniques demonstrated BPCV1 DNA within keratinocyte and sebocyte nuclei, and BPCV1 mRNA within the cytoplasm. BPCV1 virions were isolated by ultracentrifugation and visualized with negative stain transmission electron microscopy revealing icosahedral, non-enveloped viral capsids ~47 nm in diameter, comparable to viruses classified within Papillomaviridae and Polyomaviridae. A novel virus, tentatively named bandicoot papillomatosis carcinomatosis virus type 2 (BPCV2) was discovered in papillomatous lesions from a southern brown bandicoot (Isoodon obesulus). It had a circular double-stranded DNA genome of 7277 bp, and encoded two papillomavirus-like structural proteins, L1 and L2, and two polyomavirus-like putative transforming proteins, large T antigen and small t antigen. DNA and RNA in situ hybridization confirmed the presence of BPCV2 nucleic acids within lesion biopsies. The discovery of the bandicoot papillomatosis carcinomatosis viruses has provoked reassessment of the established virus taxonomy paradigm, theories of virus-host co-speciation and bandicoot population management strategies.

No description available.

Peritoneal carcinomatosis (PC), the intra-abdominal dissemination of malignancy, is equated with a 5-year survival of 15%, depending on the source. Appendiceal PC is a challenge to treat as cancer cells are embedded in copious amounts of mucin and are difficult to target. Oncolytic viruses (OVs) preferentially replicate and lyse cancer cells and present a targeted, novel strategy for PC. The hypothesis of this study is that appendiceal PC will show variable susceptibility to OVs and that protein expression in these tumours will predict OV replication efficiency. Human appendiceal PC infected ex-vivo with 4 different OVs displayed variable infectivity and replication by fluorescence microscopy and plaque assay. Immunohistochemistry analysis revealed differential expression of IRF3, pERK and TK in tumour compared to normal appendix. No correlation of protein expression with viral replication was observed. Personalizing OV therapy will be critical in the optimization of future care of patients treated with this modality.

Peritoneal carcinomatosis (PC), the intra-abdominal dissemination of malignancy, is equated with a 5-year survival of 15%, depending on the source. Appendiceal PC is a challenge to treat as cancer cells are embedded in copious amounts of mucin and are difficult to target. Oncolytic viruses (OVs) preferentially replicate and lyse cancer cells and present a targeted, novel strategy for PC. The hypothesis of this study is that appendiceal PC will show variable susceptibility to OVs and that protein expression in these tumours will predict OV replication efficiency. Human appendiceal PC infected ex-vivo with 4 different OVs displayed variable infectivity and replication by fluorescence microscopy and plaque assay. Immunohistochemistry analysis revealed differential expression of IRF3, pERK and TK in tumour compared to normal appendix. No correlation of protein expression with viral replication was observed. Personalizing OV therapy will be critical in the optimization of future care of patients treated with this modality.

Peritoneal carcinomatosis (PC) is traditionally regarded as a terminal stage of disease with a poor prognosis and systemic chemotherapy is regarded as palliative treatment. In order to improve survival and even to achieve cure for selected patients with PC, cytoreductive surgery and intraperitoneal che-motherapy have been advocated. Despite complete macroscopic removal of tumour, residual microscopic malignant cells might result in recurrence. Intraperitoneal chemotherapy aims to kill residual malignant cells and thereby needs to be distributed in the entire peritoneal cavity. This aggres-sive combined loco-regional treatment has a high risk of morbidity and mor-tality. Whether the increased risks are acceptable to improve survival re-quires investigation and the impact of loco-regional treatment of PC on health-related quality of life (HRQL) needs to bee explored The overall aim of this thesis was to analyse the impact of cytoreductive surgery and intraperitoneal chemotherapy on patients with peritoneal carci-nomatosis. A significant survival improvement (median 32 months) was seen in 18 patients with PC of colorectal origin subjected to loco-regional treatment, in comparison to matched controls treated with systemic chemotherapy (me-dian survival 14 months, Paper I). The results of single-photon emission computer-tomography (SPECT) in 51 patients were correlated to the number of intraperitoneal chemotherapy courses that could be performed without further surgery (Paper II). Postoperative 30-days morbidity and 90-days mortality was investigated in 123 PC-patients after loco-regional treatment. Severe adverse events occurred in 51 (41%) patients. Five patients (4%) had treatment-related mortality. Stoma formation, duration of surgery, periopera-tive blood loss, and extent of PC was associated with morbidity (Paper III). HRQL was investigated in 64 patients. HRQL was negatively affected at 3 months but a partial recovery was seen at 8 months. 30-day morbidity did not have any impact on HRQL at 8 months (Paper IV). This treatment there fore appears justified despite considerable toxicity in view of possible life prolongation.

Peritoneal carcinomatosis (PC) is a common manifestation of both gastrointestinal and gynecologic malignancies. Until recently, this condition was considered beyond curative intent treatment. Since the 1980s, new treatment strategies combining cytoreductive surgery (CRS) with perioperative intraperitoneal and intravenous chemotherapy have emerged. The underlying hypothesis considers CRS responsible for the removal of the macroscopic disease and that perioperative chemotherapy should address the residual microscopic disease. These new treatment regimens have presented encouraging clinical results that contrast with prior failure. The parameters for perioperative chemotherapy are mainly extrapolated from literature on peritoneal dialysis and data from systemic chemotherapy. The overall aim of this thesis was to provide a pharmacokinetic and pharmacodynamic rationale for perioperative intraperitoneal (IP) and intravenous (IV) chemotherapy in PC patients and, to assess its toxicity. After intraoperative IV administration of 5-fluorouracil or ifosfamide, substantial levels of these drugs were found inside the peritoneal fluid and tumor nodules (Papers I and II). This created a pharmacologically advantageous situation whereby a normothermic administered IV drug was subject to the effect of the local hyperthermia in the peritoneal fluid and tumor nodule. High levels of 5-fluouracil, ifosfamide and doxorubicin were observed inside the tumor nodules (Papers I, II and III) and, the identical pharmacokinetic advantage (expressed as Area Under the Curve (AUC) IP/IV ratios)) resulted in different drug levels of doxorubicin according to the density of the tumor nodules (Paper III). These data stressed the importance of pharmacodynamic variables such as tumor nodule density, size, and, vascularity. Therefore, the tumor nodule is proposed as a more appropriate pharmacological endpoint than AUC ratios. After IP Mitomycin C administration in PC patients with a contracted abdomen, mitomycin clearance from the abdomen decreased (Paper IV), which indicated  these patients at risk of under-treatment. Consequently, these pharmacologic data indicate a change in dosimetry for these treatment protocols might be warranted according to the diffusion area. Although diffusional vectors are viewed the main driving force for these treatment protocols, only pharmacokinetic variables such as dose, volume and duration are considered. As pharmacodynamic variables are equally important in the pharmacological assessment of cytotoxic effect, the tumor nodule was proposed as the center of a new conceptual model (Paper I). Mitomycin C data on non-metabolizers ( Paper IV) indicated the cytotoxicity of these cancer chemotherapy protocols is at the level of the individual tumor nodules. The morbidity and mortality of a new bidirectional intraoperative chemotherapy regimen in PC patients was analyzed (Paper V) which provided a means for identifying subsets of patients at risk for increased toxicity. This thesis provides pharmacokinetic and pharmacodynamic guidance for improving perioperative chemotherapy treatment strategies in PC patients and reports its toxicity.

De nouvelles approches sont possibles en imagerie par résonance magnétique (IRM) pour répondre aux principaux enjeux diagnostiques et thérapeutiques liés aux maladies péritonéales. Cette technique implique l'utilisation de protocoles dédiés et une courbe d'apprentissage. Après une revue de la littérature sur l'imagerie péritonéale mettant en perspective la place de l'IRM et sa potentielle sous utilisation, l'objectif de ce travail a été d'étudier l'apport de cette technique dans deux modèles de maladies péritonéales diffuses. Le premier modèle concernait l'endométriose. En utilisant des protocoles adaptés, les études sur les atteintes digestives et diaphragmatiques ont démontré qu'une cartographie lésionnelle utile au diagnostic et à la prise en charge chirurgicale gynécologique pouvait être obtenue avec de hauts niveaux de performance. Le second modèle concernait la carcinose. La problématique était d'évaluer l'apport de l'IRM dans la sélection des patients candidats à une chirurgie menée à visée curative. La première étude menée sur une grande cohorte a démontré un très faible impact des différentes techniques d'imagerie dans la sélection des patients non résécables. La seconde étude, proposant une nouvelle approche de la quantification des lésions en combinant l'IRM au scanner, a rapporté une amélioration relative du bilan lésionnel, bien qu'encore infra optimale. Avec une approche qualitative centrée sur la recherche de signes de non résécabilité, la troisième étude a démontré que l'IRM avait une meilleure sensibilité que le scanner pour détecter les atteintes non résécables de l'intestin grêle dans le pseudomyxome péritonéal. L'IRM, grâce à sa haute résolution en contraste, offre des informations uniques. Utilisée comme technique de référence ou en complément des autres techniques en fonction de la nature des lésions à explorer, elle permet d'optimiser la prise en charge des patients / Magnetic resonance imaging (MRI) allows news approaches to improve diagnostic and therapeutic issues related to peritoneal diseases. This technique requires using dedicated protocols and has a learning curve. After a literature review on peritoneal imaging highlighting the role of MRI and its potential underutilization, the purpose of this work was to study the contribution of MRI in two models of diffuse peritoneal diseases. The first model concerned endometriosis. Using dedicated protocols, studies on digestive and diaphragmatic involvements reported high performance for providing a useful mapping of lesions for both diagnosis and surgical planning. The second model concerned peritoneal carcinomatosis. The purpose was to assess the contribution of MRI in selecting patients for curative surgery. The first study, performed in a large cohort, reported a very low impact of the different imaging techniques in the selection of non-resectable patients. Using a new approach combining MRI and computed tomography (CT), the second study demonstrated a substantial improvement in quantitative lesion assessment, although remaining sub optimal. With a qualitative approach evaluating signs of non-resectability, the third study showed MRI had better sensitivity than CT for the detection of non-resecable small bowel involvements in pseudomyxoma peritonei. MRI, thanks to its high contrast resolution, provides unique information. Used as reference technique or in addition to other techniques, MRI optimizes patient management

Over the last few years, diffusion-weighted imaging (DWI) has become increasingly relevant in the diagnostic assessment of peritoneal carcinomatosis. The aim of this study was to investigate the benefits of high-b DWI (c-DWI) compared to standard DWI in patients with peritoneal carcinomatosis. A cohort of 40 patients with peritoneal carcinomatosis were included in this retrospective study. DWI was performed with b-values of 50, 400, and 800 or 1000 s/mm2 on a 1.5-T magnetic resonance imaging (MRI) scanner. C-DWI was calculated using a mono-exponential model with high b-values of 1000, 2000, 3000, 4000, and 5000 s/mm2. All c-DWI images with high b-values were compared in terms of volume, detectability of peritoneal lesions, and image quality with the DWI sequence acquired with a b-value of 800 or 1000 s/mm2 by two readers. In the group with a b-value of 800 s/mm2, there was no statistically significant difference in terms of lesion volume. In the second group with a b-value of 1000 s/mm2, peritoneal carcinomatosis lesions were statistically significantly larger than in the c-DWI with a- high b-value of 2000 s/mm2 (median 7 cm3, range 1–26 cm3vs. median 6 cm3, range 1–83 cm3, p < 0.05). In both groups, there was a marked decrease in the detectability of peritoneal lesions starting at b = 2000 s/mm2. In addition, image quality decreased noticeably from c-DWI at b = 3000 s/mm2. In both groups, all images with high b-values at b = 4000 s/mm2 and 5000 s/mm2 were not diagnostically valuable due to poor image quality. The c-DWI technique offers good diagnostic performance without additional scanning time. High c-DWI b-values up to b = 1000 s/mm2 provide comparable detectability of peritoneal carcinomatosis compared to standard DWI. Higher b-values over 1500 s/mm2 result in lower image quality, which might lead to misdiagnosis.

Small intestinal neuroendocrine tumor (SI-NET) is the most common small bowel tumor in Europe and USA, with an annual incidence of around 0.3-1.3/100000 persons. SI-NETs are the most common type of gastroenteropancreatic NETs (GEP-NETs), and they are known for their ability to produce hormones such as tachykinins and serotonin, as well as for their favorable long-term prognosis in comparison to gastrointestinal adenocarcinoma. The overall aim of the thesis was to investigate unknown or unclear aspects of SI-NET disease, in connection with prognosis, treatment and follow-up. Paper I confirmed several known negative prognostic factors and also showed, for the first time, that para-aortal lymph node metastases and peritoneal carcinomatosis were associated with worse survival by multivariable analyses. Locoregional surgery was associated with a low post-operative mortality, and a prolonged long-term survival by multivariable analysis. In Paper II we continued to investigate peritoneal carcinomatosis and found it be a risk factor not only for death, but also for emergency re-surgery. Furthermore, genetic analyses of samples from primary tumors in patients with and without peritoneal carcinomatosis showed a difference in the DNA between these two groups. In Paper III the outcome after liver surgery and/or radiofrequency ablation of liver metastases was investigated. To summarize, no difference in survival was seen in patients treated with surgery/radiofrequency ablation in comparison with matched controls. However, a superior radiological response of liver metasases and lower U-5-HIAA values were seen in patients subjected to liver surgery and/or radiofrequency ablation compared to matched controls. Paper IV compared ultrasonography, computed tomography and 11C-5HTP-PET in the follow-up after radiofrequency ablation of NET liver metastases. The study concluded that 11C-5HTP-PET depicted all residual tumors after RFA and that it, if used, should be combined with computed tomography for easier interpretation, as RFA areas are not clearly distinguishable with 11C-5HTP-PET alone. Paper V studied gallstone complications after somatostatin analog treatment in SI-NET patients, and concluded that there was a rather high risk to be subjected to a cholecystectomy due to biliary colic, cholecystitis, cholangitis or pancreatitis after primary surgery in somatostatin analog treated patients.