[De novo cancer after solid organ transplantation: Epidemiology, prognosis and management]. / Cancers solides après transplantation d'organe : épidémiologie, pronostic et spécificités de prise en charge.

The risk of cancer after solid organ transplantation is increased by 2.6 compared to overall population. Cancer is currently the third leading cause of death in solid organ transplanted patients, making screening and early management of de novo cancers a major challenge. This increased risk of cancer in this population results from the combination of known environmental risk factors of cancer, comorbidities of transplanted patients, and exposure to chronic immunosuppression. The prognosis of cancer in these patients seems poorer as compared to other cancer patients owing to their comorbidities, the immunosuppression and patient's poorer tolerance to oncologic treatment. Moreover, interactions between immunosuppressive agents and antitumor therapies must be taken into account in the therapeutic strategy. Better knowledge of the specificities of solid organ transplanted patients with de novo cancer is required to improve cancer care in this patient population. This article aims to review the current data available on de novo cancers in solid organ transplanted patients, with a focus on epidemiology, risks factors of de novo cancers, impact of immunosuppressive drugs and oncologic prognosis.

Magnetic Resonance Imaging Assessment of Kidney Oxygenation and Perfusion During Sickle Cell Vaso-occlusive Crises.

BACKGROUND: Our understanding of the pathophysiologic processes underlying sickle cell nephropathy remains incomplete. We performed a pilot study to investigate the potential value of magnetic resonance imaging (MRI) for the assessment of kidney oxygenation and detection of potential changes to tissue perfusion and cellular integrity during a vaso-occlusive crisis. STUDY DESIGN: A case-control study. SETTING & PARTICIPANTS: 10 homozygous patients with sickle cell disease (SCD), without kidney disease (based on estimated glomerular filtration rate and albuminuria), underwent renal MRI during a vaso-occlusive crisis episode. The imaging data obtained were compared with those for a second MRI performed at steady state (median, 56 [IQR, 37-72] days after the vaso-occlusive crisis MRI). The control group consisted of 10 apparently healthy individuals. MEASUREMENTS: Deoxyhemoglobin level assessed by R2* value was calculated using the blood oxygen level-dependent technique. The intravoxel incoherent motion diffusion-weighted imaging technique was used to calculate D, D*, and F parameters. RESULTS: Median medullary R2* values on steady-state MRI were significantly higher for patients with SCD than for controls (P=0.01) and did not change significantly during the vaso-occlusive crisis. No significant differences in median cortical R2* values were observed. Both cellular integrity (D) and local perfusion (D* and F) were significantly altered in medullary and cortical areas during vaso-occlusive crises in comparison to steady state in patients with SCD. These parameters did not differ significantly between patients with SCD assessed at steady state and the control group. LIMITATIONS: Small sample size, estimation of glomerular filtration rate according to CKD-EPI creatinine equation without adjustment for race. CONCLUSIONS: Deoxyhemoglobin levels in the medullary area are higher in patients with SCD, during vaso-occlusive crises and at steady state, than in controls. Alterations to the tissue perfusion and cellular integrity of renal parenchyma are a common finding during vaso-occlusive crises that provide additional evidence that a vaso-occlusive crisis may be associated with subclinical kidney injury detectable on MRI.