Le carcinome rénal à cellules chromophobes : une tumeur rare et de bon pronostic

Résumé :Il existe peu d'études dans la littérature comparant les caractéristiques anatomo-cliniques et évolutives des principales formes histologiques de carcinome rénal. Dans nombre de ces études, les carcinomes rénaux étudiés étaient de grades et de stades différents.Buts de l'étude :L'objet de notre étude était d'examiner les caractéristiques anatomo-cliniques d'une série de carcinome rénaux à cellules chromophobes (CRCCh) et de les comparer à celles des carcinomes rénaux conventionnels (CRC) et des carcinomes rénaux papillaires de type 1 (CRP1), à grade et stade équivalents.Matériel et méthodes :41 CRCCh, 40 CRP1 et 153 CRC ont été examinés en se concentrant sur les paramètres suivants : âge et sexe du patient, taille de la tumeur, stade, grade et caractéristiques histologiques. Les survies globales, survies sans récidive et survies sans métastase de chaque groupe tumoral ont été comparées, à grade et stade équivalents (méthode de Kaplan Meier). Les facteurs pronostiques les plus importants ont été recherchés (modèle de Cox).Résultats :En analyse univariée, le CRCCh est celui qui a le meilleur pronostic en terme de survie globale et de survie sans métastase parmi les tumeurs de grade et de stade équivalents. En analyse multivariée, l'histologie CRC est le facteur pronostique le plus important et le plus défavorable.Conclusion A grade et stade équivalents, le pronostic du CRCCh est sensiblement le même que celui du CRP 1 mais significativement meilleur que celui du CRC, avec lequel il ne doit pas être confondu.

The Effect of Adding CO2 to Hypoxic Inspired Gas on Cerebral Blood Flow Velocity and Breathing during Incremental Exercise

Hypoxia increases the ventilatory response to exercise, which leads to hyperventilation-induced hypocapnia and subsequent reduction in cerebral blood flow (CBF). We studied the effects of adding CO2 to a hypoxic inspired gas on CBF during heavy exercise in an altitude naïve population. We hypothesized that augmented inspired CO2 and hypoxia would exert synergistic effects on increasing CBF during exercise, which would improve exercise capacity compared to hypocapnic hypoxia. We also examined the responsiveness of CO2 and O2 chemoreception on the regulation ventilation (E) during incremental exercise. We measured middle cerebral artery velocity (MCAv; index of CBF), E, end-tidal PCO2, respiratory compensation threshold (RC) and ventilatory response to exercise (E slope) in ten healthy men during incremental cycling to exhaustion in normoxia and hypoxia (FIO2 = 0.10) with and without augmenting the fraction of inspired CO2 (FICO2). During exercise in normoxia, augmenting FICO2 elevated MCAv throughout exercise and lowered both RC onset andE slope below RC (P<0.05). In hypoxia, MCAv and E slope below RC during exercise were elevated, while the onset of RC occurred at lower exercise intensity (P<0.05). Augmenting FICO2 in hypoxia increased E at RC (P<0.05) but no difference was observed in RC onset, MCAv, or E slope below RC (P>0.05). The E slope above RC was unchanged with either hypoxia or augmented FICO2 (P>0.05). We found augmenting FICO2 increased CBF during sub-maximal exercise in normoxia, but not in hypoxia, indicating that the 'normal' cerebrovascular response to hypercapnia is blunted during exercise in hypoxia, possibly due to an exhaustion of cerebral vasodilatory reserve. This finding may explain the lack of improvement of exercise capacity in hypoxia with augmented CO2. Our data further indicate that, during exercise below RC, chemoreception is responsive, while above RC the ventilatory response to CO2 is blunted.

Fungus ball in the urinary tract: A rare entity.

A fungal mass in the urinary tract (fungus ball), mainly occurring in compromised patients, is a rare and dangerous complication of candiduria. We report 2 cases of fungus ball associated with hydronephrosis and sepsis. As reported in the literature, we treated the first patient by prompt relief of obstruction by nephrostomy and local and systemic antifungal agent. The second patient failed to respond to this treatment due to a distal ureteral stenosis and required open surgery with fungus ball removal and ureteral reimplantation. Despite a large success in urinary tract drainage with antifungal treatments, some cases need a modified approach due to anatomical modification.

Clinical trial designs for rare diseases: studies developed and discussed by the International Rare Cancers Initiative.

BACKGROUND: The past three decades have seen rapid improvements in the diagnosis and treatment of most cancers and the most important contributor has been research. Progress in rare cancers has been slower, not least because of the challenges of undertaking research. SETTINGS: The International Rare Cancers Initiative (IRCI) is a partnership which aims to stimulate and facilitate the development of international clinical trials for patients with rare cancers. It is focused on interventional--usually randomized--clinical trials with the clear goal of improving outcomes for patients. The key challenges are organisational and methodological. A multi-disciplinary workshop to review the methods used in ICRI portfolio trials was held in Amsterdam in September 2013. Other as-yet unrealised methods were also discussed. RESULTS: The IRCI trials are each presented to exemplify possible approaches to designing credible trials in rare cancers. Researchers may consider these for use in future trials and understand the choices made for each design. INTERPRETATION: Trials can be designed using a wide array of possibilities. There is no 'one size fits all' solution. In order to make progress in the rare diseases, decisions to change practice will have to be based on less direct evidence from clinical trials than in more common diseases.

Hémorragie par le canal de Wirsung: forme rare d'hémorragie digestive haute. A propos d'une observation [Hemorrhage through Wirsung's duct: rare form of upper gastrointestinal hemorrhage. A case report].

The case of a 41-year-old alcoholic patient who presented with massive upper gastrointestinal bleeding is reported. The diagnosis was established rapidly by endoscopy which revealed bleeding through the papilla of Vater. Selective angiography of the superior mesenteric artery opacified the pancreatic duct as well as the duodenum. CT scan showed signs of chronic pancreatitis. Because of the recurrence of bleeding and shock, an urgent operation was necessary and a Whipple procedure was performed. Recovery was complete. The clinical presentation, the etiology, the diagnostic modalities and the treatment of this particular condition are discussed. Usually, hemorrhage through the pancreatic duct presents as repeated episodes of upper gastrointestinal bleeding with no source found at endoscopy. The presence of chronic pancreatitis or of epigastric pain during bleeding should suggest the diagnosis. Upper gastrointestinal endoscopy and angiography are the principal diagnostic tools. Definitive treatment requires surgery, and resection in most of the cases.

When gas analysis assists with postmortem imaging to diagnose causes of death.

Postmortem imaging consists in the non-invasive examination of bodies using medical imaging techniques. However, gas volume quantification and the interpretation of the gas collection results from cadavers remain difficult. We used whole-body postmortem multi-detector computed tomography (MDCT) followed by a full autopsy or external examination to detect the gaseous volumes in bodies. Gases were sampled from cardiac cavities, and the sample compositions were analyzed by headspace gas chromatography-mass spectrometry/thermal conductivity detection (HS-GC-MS/TCD). Three categories were defined according to the presumed origin of the gas: alteration/putrefaction, high-magnitude vital gas embolism (e.g., from scuba diving accident) and gas embolism of lower magnitude (e.g., following a traumatic injury). Cadaveric alteration gas was diagnosed even if only one gas from among hydrogen, hydrogen sulfide or methane was detected. In alteration cases, the carbon dioxide/nitrogen ratio was often >0.2, except in the case of advanced alteration, when methane presence was the best indicator. In the gas embolism cases (vital or not), hydrogen, hydrogen sulfide and methane were absent. Moreover, with high-magnitude vital gas embolisms, carbon dioxide content was >20%, and the carbon dioxide/nitrogen ratio was >0.2. With gas embolisms of lower magnitude (gas presence consecutive to a traumatic injury), carbon dioxide content was <20% and the carbon dioxide/nitrogen ratio was often <0.2. We found that gas analysis provided useful assistance to the postmortem imaging diagnosis of causes of death. Based on the quantifications of gaseous cardiac samples, reliable indicators were determined to document causes of death. MDCT examination of the body must be performed as quickly as possible, as does gas sampling, to avoid generating any artifactual alteration gases. Because of cardiac gas composition analysis, it is possible to distinguish alteration gases and gas embolisms of different magnitudes.