[Imaging in nephroureterolithasis]. / Bildgebung bei Nephroureterolithiasis.

In the acute diagnostics of a suspected nephroureterolithiasis, ultrasonography should be the examination modality of choice. In cases of suspected urolithiasis, unclear flank pain with fever or in cases of a solitary kidney, a noncontrast computed tomography (CT) scan should always subsequently be performed. If the sonography findings are inconclusive in pregnant women a magnetic resonance imaging (MRI) examination can be considered. If there are indications for urinary diversion, a retrograde imaging study should be performed as part of the urinary diversion. This or CT imaging is also suitable for preinterventional imaging before shock wave lithotripsy, percutaneous nephrolithotomy or ureteroscopy. Postinterventional imaging is not always necessary and sonography is often sufficient. In a conservative treatment approach an abdominal plain X­ray can be used for follow-up assessment.

Feasibility and Toxicity of Full-Body Volumetric Modulated Arc Therapy Technique for High-Dose Total Body Irradiation.

Introduction: High-dose total body irradiation (TBI) is often part of myeloablative conditioning in acute leukemia. Modern volumetric modulated arc therapy (VMAT)-based plans employ arcs to the inferior-most portion of the body that can be simulated in a head-first position and use 2D planning for the inferior body which can result in heterogeneous doses. Here, we describe our institution's unique protocol for delivering high-dose TBI entirely with VMAT and retrospectively compare dosimetric outcomes with helical tomotherapy (HT) plans. Additionally, we describe our method of oropharyngeal mucosal sparing that was implemented after fatal mucositis occurred in two patients. Methods: Thirty-one patients were simulated and treated in head-first (HFS) and feet-first (FFS) orientations. Patients were treated with VMAT (n = 26) or HT (n = 5). In VMAT plans, to synchronize doses between the orientations, images were deformably registered and the HFS dose was transferred to the FFS plan and used as a background dose when optimizing plans. Six to eight isocenters with two arcs per isocenter were generated. HT was delivered with an established technique. Patients were treated to 13.2 Gy over eight twice daily fractions. Dosimetric outcomes and toxicities were retrospectively compared. Results: Prescription dose and organ at risk (OAR) constraints were met for all patients. Lower lung doses were achieved with VMAT relative to HT plans (7.4 vs 7.7 Gy, P = .009). Statistically significant improvement in mucositis was not achieved after adopting a mucosal-sparing technique, however lower doses to the oropharyngeal mucosal were achieved (6.9 vs 14.1 Gy, P = .009), and no further mucositis-related deaths occurred. Conclusions: This full-body VMAT method of TBI achieves dose goals, eliminates risk of heterogenous doses within the femur, and demonstrates that selective OAR sparing with the purpose of reducing TBI-related morbidity and mortality is possible at any institution with a VMAT-capable linear accelerator.

Gonadal-sparing total body irradiation with the use of helical tomotherapy for nonmalignant indications.

BACKGROUND: The aim was to demonstrate the feasibility and technique of gonadal sparing total body irradiation (TBI) with helical tomotherapy. Total body irradiation is a common part of the conditioning regimen prior to allogeneic stem cell transplantation. Shielding or dose-reduction to the gonads is often desired to preserve fertility, particularly in young patients undergoing transplant for non-malignant indications. Helical tomotherapy (HT) has been shown to be superior to traditional TBI delivery for organ at risk (OA R) doses and dose homogeneity. MATERIALS AND METHODS: We present two representative cases (one male and one female) to illustrate the feasibility of this technique, each of whom received 3Gy in a single fraction prior to allogeneic stem cell transplant for benign indications. The planning target volume (PTV) included the whole body with a subtraction of OA Rs including the lungs, heart, and brain (each contracted by 1cm) as well as the gonads (testicles expanded by 5 cm and ovaries expanded by 0.5 cm). RESULTS: For the male patient we achieved a homogeneity index of 1.35 with a maximum and median planned dose to the testes of 0.53 Gy and 0.35 Gy, respectively. In-vivo dosimetry demonstrated an actual received dose of 0.48 Gy. For the female patient we achieved a homogeneity index of 1.13 with a maximum and median planned dose to the ovaries of 1.66 Gy and 0.86 Gy, respectively. CONCLUSION: Gonadal sparing TBI is feasible and deliverable using HT in patients with non-malignant diseases requiring TBI as part of a pre-stem cell transplant conditioning regimen.

Double-hit monomorphic B-cell lymphoma after liver transplantation.

We report the first case of double-hit (MYC and BCL-6) monomorphic post-transplant lymphoproliferative disorder in a patient status post liver transplantation. Our patient is a 71-year-old man with a past medical history of Budd-Chiari syndrome complicated by cirrhosis and hepatocellular carcinoma. He underwent a deceased donor liver transplantation 2 years prior to presentation and was maintained on tacrolimus and mycophenolate mofetil for immunosuppression. He presented with a 3-week history of classical B-symptoms. Initial workup was notable for elevated lactate dehydrogenase. Abdomen ultrasound revealed multiple hypoechoic lesions, raising suspicion for a post-transplant lymphoproliferative disorder. Biopsy showed pleomorphic large neoplastic cells throughout, consistent with a diagnosis of diffuse large B-cell lymphoma. Cytogenetics then revealed rearrangements in both MYC and BCL-6, consistent with double-hit lymphoma. His immunosuppressive regimen was subsequently tapered and he was started on DA-EPOCH-R (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin and rituximab) regimen.

Determinants of inequalities in cervical cancer stage at diagnosis and survival in New Zealand.

OBJECTIVE: The aim of this study is to assess whether ethnic inequalities in cervical cancer mortality are due to differences in survival independent of stage and age at diagnosis, and to assess the contribution of screening to stage at diagnosis. METHODS: Demographic data and cervical screening history were collected for 402 women with histologically proven primary invasive cervical cancer, diagnosed in New Zealand between 1 January 2000 and 30 September 2002. Date of death was available for women who died up to 30 September 2004. RESULTS: A Cox proportional hazard model showed that, after adjusting for age, the Maori mortality rate was 1.80 times (95% CI 1.07-3.04) that of non-Maori. This reduced to 1.25 (95% CI 0.74-2.11) when stage at diagnosis was also adjusted for. Among determinants of late stage at diagnosis, older age and being Maori significantly increased the risk, while screening was protective. CONCLUSIONS: These results indicate that later stage at diagnosis is the main determinant of Maori women's higher mortality from cervical cancer. Improving cervical screening among Maori women would reduce stage at diagnosis and therefore ethnic inequalities in mortality.

Biochemical and genetic studies of the VPg uridylylation reaction catalyzed by the RNA polymerase of poliovirus.

The first step in poliovirus (PV) RNA synthesis is the covalent linkage of UMP to the terminal protein VPg. This reaction can be studied in vitro with two different assays. The simpler assay is based on a poly(A) template and requires synthetic VPg, purified RNA polymerase 3D(pol), UTP, and a divalent cation. The other assay uses specific viral sequences [cre(2C)] as a template for VPg uridylylation and requires the addition of proteinase 3CD(pro). Using one or both of these assays, we analyzed the VPg specificities and metal requirements of the uridylylation reactions. We determined the effects of single and double amino acid substitutions in VPg on the abilities of the peptides to serve as substrates for 3D(pol). Mutations in VPg, which interfered with uridylylation in vitro, were found to abolish viral growth. A chimeric PV containing the VPg of human rhinovirus 14 (HRV14) was viable, but substitutions of HRV2 and HRV89 VPgs for PV VPg were lethal. Of the three rhinoviral VPgs tested, only the HRV14 peptide was found to function as a substrate for PV1(M) 3D(pol) in vitro. We also examined the metal specificity of the VPg uridylylation reaction on a poly(A) template. Our results show a strong preference of the RNA polymerase for Mn(2+) as a cofactor compared to Mg(2+) or other divalent cations.