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Multiple myeloma (MM) is a neoplastic proliferation of plasma cells within the bone marrow. The disease is characterized by a plasma cell infiltrate of the bone marrow, osteolytic bone lesions, and the presence of monoclonal protein in the serum or urine with extraosseous involvement by disease less common. Although the skeletal survey has long been the standard investigation in these patients, there have been significant recent advances in computed tomography (CT), magnetic resonance imaging (MRI), and functional imaging. We present a comprehensive review of the evidence for the use of each of these studies in the diagnosis, prognosis, assessment of complications, and response evaluation in patients with MM.

The lymphomas are a heterogeneous group of malignant diseases. They are divided into two broad groups: Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). Patients suffering from HD and NHL can be cured by appropriate chemotherapy and/or radiotherapy. Accurate staging and response assessment is essential to guide management decisions. The International Workshop Group (IWG) criteria, published in 1999, have become the widely accepted standard for response assessment in NHL. Although the IWG criteria have proved extremely useful in the standardization of treatment response, they do have a number of limitations. As a consequence of this, together with advances in functional imaging, revised criteria have been published recently. The aim of this review is to describe the evidence supporting the available imaging techniques, the limitations of each technique, and how these should be applied in clinical practice. We briefly review the corresponding response criteria for central nervous system (CNS) lymphomas, and take a look at novel imaging techniques that may play a role in the future.

Aim To examine the usage and value of computed tomography (CT) following simultaneous pancreas and kidney (SPK) transplantation. Materials and methods Indications for postoperative CT, key findings, and their influence on management were determined by retrospective analysis. Results Ninety-eight patients underwent 313 CT examinations. Common indications for the examinations included suspected intra-abdominal collection (31.1%) and elevated serum amylase/lipase (24.1%). CT findings most frequently showed non-specific mild inflammation (27.6%), a normal scan (17.1%) and fluid collections (16.3%). High capillary blood glucose (CBG) was associated with resultant CT demonstration of graft vascular abnormalities, but otherwise, particular clinical indications were not associated with specific CT findings. Conclusion Clinical findings in patients with SPK transplants are non-specific. The pattern of abnormalities encountered is significantly different to those seen in native pancreatic disease and demands a tailored protocol. CT enables accurate depiction of vascular abnormalities and fluid collections, thus reducing the number of surgical interventions that might otherwise be required. Elevated CBG should prompt urgent CT to exclude potentially reversible vascular complications.

Normal haemostasis relies on the complex interactions of the coagulation cascade, platelets, and the endothelium. In this review, the roles of each of these elements are described as well as common causes for their derangement. Haemostasis may be manipulated via pharmacological means and in recent years there has been a significant increase in the number of agents available for influencing haemostatic mechanisms. It is essential that radiologists are aware of these mechanisms and drugs if they are to perform image-guided procedures safely. In addition to describing the relevant pathways and drugs, practical tips are provided.

Aim To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy. Materials and methods Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation. Results Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65–75% and specificity of 47–88% for detection of HCC lesions. The sensitivity dropped to 48–57% for lesions of size ≤20 mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4–26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist. Conclusion Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

The lymphomas are a heterogeneous group of malignancies, which exhibit a range of different molecular features, genetics, and clinical presentations. Consequently, therapeutic approaches and clinical outcomes differ greatly. Following therapy, the thorax may be a site of disease recurrence, but infection, drug reactions, and radiation pneumonitis are commonly encountered. We present a comprehensive review of these conditions, focussing on their radiological appearances, in order that radiologists may better engage their colleagues in haemato-oncology.

Glucose turnover, glycerol turnover, and the rate of incorporation of glycerol carbon into glucose were measured with the tracer technique (primed constant rate infusion) using 2-3H-glucose and 14C-glycerol, at rest and during exercise (treadmill run) in normal (N), alloxan-diabetic (D), and methylprednisolone treated diabetic (MPD) dogs. At rest only 2%-3% of the hepatic glucose output arose from glycerol. Exercise increased gluconeogenesis about ninefold in N dogs and about fourfold in D and MPD animals, yet less than 9% of the elevated glucose turnover was derived from glycerol. There was a direct linear correlation between the rates of glycerol turnover and gluconeogenesis from glycerol at rest and during exercise in all three groups. The slope constants were however significantly different: 0.45, 0.51, and 0.67 for N, D, and MPD dogs, respectively. In vivo the major factor controlling the rate of gluconeogenesis from glycerol seems to be the glycerol supply on which the specific effects of insulin deficiency and glucocorticoid treatment are superimposed. They appear to be of minor importance. A comparison of the glucose turnover measured by 2-3H-glucose with that measured by 6-3H-glucose showed that the activity of the glucose in equilibrium glucose-6-P cycle was threefold higher in D dogs and elevated by 15-fold in MPD animals.

Dogs with indwelling polyethylene arterial and venous catheters ran on a treadmill (slope 15 per cent, speed 100 m./min.). Diabetes was produced by alloxan or by a combination of alloxan and streptozotocin. Glucose turnover was measured according to the primed constant-rate infusion technics with 2-3H-glucose as tracer. In resting diabetic dogs plasma glucose varied between 200 and 650 mg./100 ml. There was a direct linear correlation between the hepatic glucose output (Ra) and the plasma glucose level. Exercise increased both Ra and the clearance rate (CR) of glucose; however, Ra could not match the rate of disappearance (=renal loss plus glucose uptake of the muscle), causing the plasma glucose to decline more rapidly than in the running control dogs. Two to three daysʹ treatment with methylprednisolone (MP, 3-3.2 mg./kg./day) caused a higher resting glucose level and a higher Ra. Exercise greatly increased the plasma glucose concentration, partly because MP enhanced the hepatic response but mainly because it essentially prevented the rise of CR. It is concluded that (a) in chemically induced diabetes, the variable glucose level is the result of a variable rate of hepatic glucose output; (b) the increase of Ra by MP treatment does not increase the plasma glucose in the normal dog but significantly aggravates the alloxan diabetes, (c) diabetes reduces the effect of exercise on the glucose uptake of the muscle, and this effect is potentiated by the inhibitory action of the glucocorticoid. This latter becomes unmasked only when the insulin secretion is impaired.

HIV Nef protein downregulates the surface expression of CD4 on T-cells but its mechanism of activity is unknown. We have analyzed the relevance of different portions of the CD4 molecule with respect to the activity of Nef. Upon transfection of Jurkat T-cells that express Nef or do not express Nef with constructs that include different domains of the CD4 molecule, we demonstrated that Nef downregulation of CD4 requires the first 30 amino acids of the CD4 cytoplasmic tail and that the Ick-binding domain of CD4 was at least partially responsible for this effect. Furthermore, upon transfection of U-937 cells with an Ick-expressing plasmid we showed that CD4 downregulation by Nef is significantly more efficient when Ick is present. Finally, by measuring the rate of CD4 endocytosis by a novel flow cytometric method we showed that the effect of Nef on CD4 surface expression resulted from accelerated CD4 internalization.