Detection of neuroendocrine liver metastases with MnDPDP-enhanced MRI.

PURPOSE: The sensitivity of computerised tomography (CT) in detecting neuroendocrine liver metastases is variable and three-phase imaging is advocated. However, patients are often young and may require prolonged follow-up, thus a technique that avoids radiation exposure would be desirable. Our purpose was to assess the diagnostic performance of MRI, before and after administration of mangafodipir trisodium (MnDPDP), in the detection of neuroendocrine liver metastases. METHODS: Patients who had undergone single-phase or multi-phase contrast-enhanced MD-CT for neuroendocrine liver metastases were invited to have MRI. Two independent observers made quantitative measurements (number and size of lesions). All measurements were made on each available CT phase and all MRI sequences independently, and repeated after an interval to assess reproducibility. The final number of lesions was agreed on by consensus of three observers. A qualitative assessment (contrast and spatial resolution) and preferred modality were agreed on by consensus. RESULTS: 265 lesions were detected by consensus in 11 patients. Non-contrast CT was available in 4/11, arterial phase in 6/11 and portal phase in 10/11 patients. When compared with the consensus number of lesions, MD-CT identified 17% on non-contrast, 44% on arterial and 43% on portal venous imaging. Lesion detection on MRI was 48% on T(1)W, 52% on T(2)W and 92% on MnDPDP-MRI. The number of lesions detected on MnDPDP-MRI was closest to the final consensus reading (variance = 0.994, p = 0.0027). The reproducibility of lesion size measurements was best on MnDPDP-MRI (variance = 0.033, p = 0.0021). The preferred modality subjectively was MnDPDP-MRI in 9/11 cases and T(2)W MRI in 2/11. CONCLUSION: MRI is a robust technique in the demonstration of neuroendocrine liver metastases. It is highly reproducible in both detecting the number and measuring the size of lesions. We recommend T(2)W MRI and MnDPDP-MRI in detection and follow-up of neuroendocrine liver metastases.

MRI appearances of borderline ovarian tumours.

This review was performed to describe the range of magnetic resonance imaging (MRI) appearances of borderline ovarian tumours. The MRI findings in 26 patients with 31 borderline ovarian tumours (mean age: 40.1 years, range: 14-85 years) were retrospectively reviewed. For each tumour, site, size, MRI characteristics, and enhancement following gadolinium administration were recorded. There were 20 serous and 11 mucinous borderline ovarian subtypes. Nine of 26 patients demonstrated bilateral disease on MRI; synchronous contralateral ovarian disease included three benign, five serous borderline, and one serous invasive tumour. A history of a metachronous mucinous borderline tumour was identified in one patient. MRI appearances were classified into four morphological categories: group 1 (6/31, 19%), unilocular cysts; group 2 (6/31, 19%), minimally septate cysts with papillary projections; group 3 (14/31, 45%), markedly septate lesions with plaque-like excrescences; and group 4 (5/31, 16%), predominantly solid with exophytic papillary projections, all of serous subtype. There was a significant difference in mean volume between serous (841.5 cm(3)) and mucinous (6358.2 cm(3)) subtypes (p=0.009). All tumours demonstrated at least one MRI feature suggestive of malignancy. The present review demonstrates the variable MRI appearances of borderline ovarian tumours along with imaging features suggestive of tumour subtype. In patients in whom the clinical features are suggestive of a borderline ovarian tumour (young age and normal or minimally elevated CA125), the ability to predict a borderline disease using morphological features observed on MRI would be extremely helpful in surgical planning, with the potential to offer fertility or ovary-preserving surgery. Future studies are required to further this aim.

Computed tomography features of recurrent ovarian carcinoma according to time to relapse.

BACKGROUND: Although the sites of recurrent ovarian cancer are individually described in the literature, patterns of recurrent disease are poorly understood. PURPOSE: To describe CT patterns of disease in recurrent ovarian cancer. To emphasize common patterns, recognise subtle and unusual sites of recurrent disease. MATERIALS AND METHODS: We identified patients between 1981-2004 presenting with clinical recurrence or elevated CA 125 after complete primary clinical and radiological response. CT imaging at primary diagnosis, during and after treatment and at recurrence was retrospectively reviewed. Site, distribution, stage of disease and time to relapse was recorded. RESULTS: 400 patients were treated for ovarian cancer. 214(54%) achieved complete primary response. 161(75%) relapsed with complete imaging available in 67 patients. Of the 67 patients, 14 (21%) recurred within 1 year, 44 (66%) relapsed between 1-5 years. Therefore 87% of relapses occurred within 5 years following primary treatment. Five (8%) relapsed between 5-10 years and 4 (6%) relapsed after 10 years. Commonest pattern of relapse was pelvic mass in 35 (48%) patients, solitary in 15 (22%). 27 (45%) relapsed with peritoneal thickening, 27 (45%) had small or large bowel serosal disease, 22 (33%) had enlarged lymphadenopathy, 6 as sole manifestation of recurrence, 20 (30%) presented with unusual sites of recurrence: 6 splenic, 10 hepatic, 2 biliary, 3 brain and 2 muscle. CONCLUSION: Our study is the first to describe common patterns of recurrence in ovarian cancer. Most frequent site is pelvis, followed by peritoneum, serosal surfaces and nodal disease. 30% presented with disease at 'unusual' sites.

Selective parathyroid venous sampling in patients with complicated hyperparathyroidism.

OBJECTIVE: The role of preoperative localisation of abnormal parathyroid glands remains controversial but is particularly relevant to the management of patients with recurrent or persistent hyperparathyroidism and familial syndromes. We report our experience of the use of selective parathyroid venous sampling (PVS) in the localisation of parathyroid disease in such patients. DESIGN: We report a retrospective 10-year experience (n = 27) of the use of PVS in complicated primary hyperparathyroidism and contrast the use of PVS with neck ultrasound, magnetic resonance imaging (MRI), computed tomography (CT) and sestamibi imaging modalities. RESULTS: In 14 out of 25 patients who underwent surgery PVS results were completely concordant with surgical and histological findings and 88% of patients achieved post-operative cure. Out of 13 patients referred after previous failed surgery, 12 underwent further surgery which was curative in 9. In total PVS yielded useful positive (n = 13) and/or negative information (n = 6) in 19 out of 25 patients undergoing surgery. Using histology as the gold standard, 59% of PVS studies were entirely consistent with histology, as compared with 39% of ultrasound scans, 36% of sestamibi scans and 17% of MRI/CT scans. CONCLUSIONS: PVS is a valuable adjunct to MRI/CT and sestamibi scanning in selected patients with complicated hyperparathyroidism when performed in an experienced unit.

Role of image-guided core-needle biopsy in the management of patients with lymphoma.

PURPOSE: The results of 106 radiologically guided core needle biopsies in 96 patients were analyzed retrospectively to evaluate the accuracy, safety, and role of this technique in the management of patients with lymphoma and to determine factors predictive of success. PATIENTS AND METHODS: Biopsies were performed in 51 patients with low-grade non-Hodgkin's lymphoma (NHL), 24 with high-grade NHL, 16 with previously diagnosed Hodgkin's disease (HD), and 15 with no previous history of lymphoma. Disease was infradiaphragmatic in 92 patients and supradiaphragmatic in 14. Computed tomography (CT) guidance was used in 98 biopsies and ultrasonography (US) in eight. RESULTS: The biopsy was diagnostic and yielded information on the basis of which treatment was started in 88 of 106 patients. The procedure was well tolerated and there were no major complications. Small size of the sample or inappropriate tissue sampled were the main causes of failure. The technique was equally successful in the diagnosis of HD and both high-grade and low-grade NHL as in nonlymphoproliferative disorders. The procedure was equally successful at diagnosis as at suspected recurrence or progression. In 33 of 80 cases in which the biopsy was performed at the time of recurrence or progression, the histology had changed; in 31 of 33, this influenced treatment. The technique was efficient at diagnosing transformation of follicular NHL in 16 of 18 patients, which allowed early adjustment of treatment at recurrence. CONCLUSION: At St Bartholomew's Hospital (SBH), image-guided core-needle biopsy has proven to be a quick, safe, and efficient alternative to excisional biopsy in the evaluation of lymphoproliferative disorders at presentation, recurrence, or progression. It should become the procedure of choice for histologic sampling in the absence of peripheral lymphadenopathy.

A randomized trial to evaluate the effect of schedule on the activity of etoposide in small-cell lung cancer.

Etoposide is an increasingly used and well-tolerated drug in cancer medicine. Its cytotoxic action is phase-specific and it has demonstrated schedule dependency in both in vitro and animal studies, but clinical evidence of the importance of drug scheduling is uncertain. The two administration schedules of etoposide that have been compared in this randomized study of 39 patients with previously untreated extensive small-cell lung cancer treated with single-agent etoposide were 500 mg/m2 as a continuous intravenous (IV) infusion over 24 hours or five consecutive daily 2-hour infusions each of 100 mg/m2. Both regimens were repeated every 3 weeks, for a maximum of six cycles. Patients received combination chemotherapy with vincristine, doxorubicin, and cyclophosphamide (VAC) or radiotherapy on failure to respond or at relapse, depending on their Karnofsky performance status. The same therapy was used in both arms of the study. All patients are evaluable for response to etoposide. In the 24-hour arm, two patients achieved a partial remission, resulting in an overall response rate of 10%. In the 5-day schedule, 16 patients had a partial response and one had a complete remission, producing an overall response rate of 89%, which was significantly superior to that in the 24-hour arm (P less than .001). The median duration of remission to etoposide in the 5-day arm was 4.5 months. Bone marrow toxicity was similar in both schedules. Etoposide pharmacokinetics were measured in all patients, and total areas under the concentration versus time curves (AUCs) were equivalent in both regimens. This study has clearly demonstrated the importance of etoposide scheduling in humans, and the superiority of five daily infusions over a 24-hour continuous infusion. The response rate to single-agent etoposide using an efficacious schedule in extensive small-cell lung cancer has been determined to be in excess of 80%.

Imaging functional adrenal disorders.

Technological developments in cross-sectional imaging have revolutionized the localization and characterization of functioning adrenal pathology. With effective use of modern imaging, the diagnosis of the cause and nature of functioning adrenal pathology can be reached speedily, accurately and efficiently in the majority of patients. We review the appearance of primary and secondary adrenal pathology, evaluate the diagnostic performance of imaging modalities, highlight newer technical developments, and propose a rational use of these tests in identifying functioning adrenal disease.

Imaging evaluation of the non-functioning indeterminate adrenal mass.

With the increasing use of abdominal cross-sectional imaging in the investigation of patient symptoms and in cancer staging, incidental adrenal masses are frequently detected. The most common clinical question is whether these masses are benign or malignant. Benign adrenal masses such as myelolipomas, lipid-rich adenomas, adrenal cysts and adrenal haemorrhage have pathognomonic imaging findings. However, there remains a significant overlap between the imaging appearances of some lipid-poor adenomas and malignant lesions, particularly metastases and small adrenal carcinomas. Our review looks at the recent advances in computed tomography, magnetic resonance imaging and positron emission tomography, which can be used to assist in the distinction between benign adenomas and malignant lesions of the adrenal gland.

Computed tomography appearance of the thymus and anterior mediastinum in active Cushing's syndrome.

Computed tomography (CT) evaluation of the thymus and anterior mediastinum is an important aspect of the investigation of patients with ACTH-dependent Cushing's syndrome in order to exclude an ACTH-secreting carcinoid tumor. We have reviewed the CT imaging of the thymus and anterior mediastinum in a series of 85 patients (55 females; median age 41, range 7-77 yr) with active Cushing's syndrome as there are few data on the range of appearances in hypercortisolemic states. One patient had a thymic carcinoid tumor (24 x 18 mm). Of the others, 28/84 (33%) patients showed thymic remnant tissue, consisting of either nodule(s) at least 5 mm diameter (n = 21, mean diameters 12.5 +/- 5 x 9.6 +/- 4 mm), or triangular bilobed glands (n = 7, mean thickness of the body, right and left limbs 25 +/- 7, 14 +/- 3, and 12 +/- 5 mm). Thymic involution appeared in 56/84 (67%) patients, ranging from small nodule(s) of less than 5mm diameter to linear soft tissue strands and complete fatty replacement. Patients with thymic remnant tissue were younger than those with thymic involution (P < 0.05). The thymic carcinoid tumor could be distinguished from remnant tissue on the basis of age and size. The presence of anterior mediastinal nodule(s) in hypercortisolemia need not imply the presence of a thymic carcinoid tumor, although in older patients this should arouse suspicion.

Emergency and prolonged use of intravenous etomidate to control hypercortisolemia in a patient with Cushing's syndrome and peritonitis.

We report the emergency and prolonged use of etomidate to control circulating cortisol levels in a patient with Cushing's syndrome secondary to ectopic ACTH production from a pancreatic islet cell tumor. Duodenal perforation and peritonitis complicated an episode of salmonella septicemia, precluding the use of conventional oral medical adrenolytic therapy. Endogenous cortisol secretion was abolished by parenteral etomidate, allowing serum cortisol levels to be controlled with an iv infusion of hydrocortisone over an 8-week period in intensive care before definitive pancreatic surgery.

Hepatic steatosis in Cushing's syndrome: a radiological assessment using computed tomography.

OBJECTIVE: Hepatic steatosis may occur in association with insulin resistance and obesity, two features commonly seen in Cushing's syndrome (CS). The aim of this report is to assess the prevalence of hepatic steatosis in patients with active CS using computed tomography (CT) and to identify any associations between hepatic steatosis, endocrine and biochemical variables and body fat distribution. PATIENTS AND MEASUREMENTS: We identified 50 patients with active CS in whom appropriate CT was available to allow measurement of liver and spleen attenuation. In 26 patients, abdominal fat measurements were also available. Serum markers of CS and liver function tests were recorded. RESULTS: Ten of 50 patients had a liver-to-spleen CT attenuation ratio (L/S) of less than 1, indicating hepatic steatosis. There was a significant negative correlation between both liver attenuation and L/S ratio with total abdominal fat area, visceral fat area, the percentage of visceral fat and the visceral to subcutaneous fat ratio; the strongest negative correlation was found between visceral fat area and L/S ratio (r=-0.638, P<0.001, n=26). L/S ratio positively correlated with alkaline phosphatase levels (r=+0.423, P=0.044, n=23) but with no other serum marker of CS activity or liver enzyme. CONCLUSIONS: We have demonstrated hepatic steatosis on CT in 20% of patients with active CS. The presence of hepatic steatosis was significantly correlated with total abdominal fat area and visceral fat area.

Computed tomography assessment of fat distribution in male and female patients with Cushing's syndrome.

OBJECTIVE: Our aims were to describe the abdominal fat distribution in male patients with Cushing's syndrome (CS) on computerised tomography (CT), to compare our findings with non-cushingoid patients, to validate previous reports of increased visceral fat in female patients with CS and to identify any correlations between fat distribution and biochemical findings. DESIGN: Retrospective and observational. PATIENTS: Appropriate CT scans were identified in 31 patients (seven male) with active CS. MEASUREMENTS: Total, visceral and subcutaneous fat areas were obtained. The percentage of visceral fat and the visceral to subcutaneous fat ratio (V:S ratio) were calculated. Biochemical data were recorded. Control data of fat distribution were obtained from the literature. RESULTS: There was a significant increase in the V:S ratio in male patients with CS when compared with non-cushingoid controls (1.175+/-0.59 vs 0.77+/-0.39, 95% confidence interval (CI) 0.0817-0.728). There was a significant increase in the V:S ratio in female patients with CS (0.845+/-0.53 vs 0.38+/-0.19, 95% CI 0.269-0.661). There was no difference in the V:S ratio between male and female patients with CS (1.175+/-0.59 vs 0.845+/-0.53, 95% CI -0.144-0.804). No significant correlations between fat distribution and glucose levels, circulating cortisol, ACTH or lipids were found. CONCLUSIONS: Our data demonstrate an increase in visceral fat distribution in both male and female patients with CS, with the abolition of the normal male to female difference in visceral fat. Increased visceral fat may increase the risk of the metabolic syndrome in this group of patients.

Relative value of computed tomography scanning and venous sampling in establishing the cause of primary hyperaldosteronism.

The purpose of this study was to evaluate the relative merits of the postural stimulation test, adrenal computed tomography (CT) and venous sampling in the differential diagnosis of patients presenting with primary hyperaldosteronism. The records of 20 patients presenting with primary hyperaldosteronism were reviewed retrospectively. There were 15 patients with a unilateral aldosterone-producing adenoma (APA), four patients with idiopathic hyperaldosteronism (IHA) and one patient with primary adrenal hyperplasia (PAH). The postural stimulation test was based on measurements of plasma aldosterone and renin activity at 08.00 h and at noon after 4 h of ambulation. The CT scans of the adrenals were reviewed by a single radiologist. Bilateral venous sampling of adrenal veins was attempted in all patients and blood collected for aldosterone and cortisol assay. Plasma aldosterone concentration increased after 4 h of standing in all cases of hyperplasia but was also demonstrated in 10/15 patients with a surgically-proven APA. If one defines a significant postural rise as being greater than 30%, then 8/15 patients with APA can be considered as being posturally responsive. Computed tomography scanning correctly identified all 15 cases of APA and also classified correctly the remaining five cases of hyperplasia (four cases of IHA and one case of PAH). Venous sampling failed technically in 4/15 cases of APA and in one case of IHA: a total of 5/20 (25%,). A correct diagnosis of APA or IHA was established in all the remaining cases. However, the one case of PAH was treated successfully by adrenalectomy following venous sampling, which suggested a unilateral adrenal lesion: this one result was the only instance where venous sampling altered clinical decision-making. Computed tomography scanning may be used alone to confirm the cause of hyperaldosteronism where postural studies suggest an adrenal adenoma, and such patients may be considered for early surgery. Venous catheterization studies are not necessary routinely. but may still be useful in selected patients, particularly when CT scanning shows no clear lesion.

Percutaneous nephrostomy.

This article highlights the indications, techniques, and complications of percutaneous nephrostomy. The authors' comments are based on their experience with more than 200 patients.

Magnetic resonance imaging in idiopathic retroperitoneal fibrosis: measurement of T1 relaxation time.

Magnetic resonance imaging at 0.08 Tesla was performed in nine patients with proven idiopathic retroperitoneal fibrosis. A total of 11 scans was performed. Three patients were scanned before diagnosis; one of these also had two follow-up scans. A further six patients were scanned a variable time after diagnosis and treatment. On each scan, a periaortic soft-tissue mass was readily identified, the distribution corresponding to that seen on computed tomography. There was no difference in the mean T1 relaxation time of the mass between patients scanned before diagnosis and those scanned after treatment. However, the patient followed with serial scans showed a progressive reduction in the T1 value of the mass with time. Comparison with results obtained in patients with lymphoma suggests that the T1 values in retroperitoneal fibrosis are lower than in lymphoma, particularly non-Hodgkin's lymphoma.

CT assessment of tumour response to treatment: comparison of linear, cross-sectional and volumetric measures of tumour size.

Changes in cross-sectional area are currently used to assess tumour response to treatment. The aims of this study were to validate a helical CT technique for volume determination using a series of phantoms and to compare tumour responses indicated by one-, two- and three-dimensional measures of tumour size change in patients treated for germ cell cancer or lymphoma. All studies were performed on an IGE HiSpeed Advantage helical CT scanner with an Advantage Windows workstation. Phantom volumes were calculated using volume reconstruction software and compared with reference volumes determined by water displacement. 20 lymph node masses were studied on serial CT scans in 16 patients treated with chemotherapy for germ cell cancer or lymphoma. For each lesion the maximum diameter, maximum cross-sectional area and volume were determined before and after treatment. Tumour response was assessed using the standard World Health Organisation criteria (i.e. changes in cross-sectional area) and the newly proposed unidimensional response evaluation criteria in solid tumour (RECIST). The CT volume measurement error was 1.0-5.1% for regularly shaped phantoms larger than 35 cm3. In the assessment of treatment response there was 90% agreement between one-dimensional (1D) and two-dimensional (2D) measurements and 100% agreement between 2D and three-dimensional (3D) measurements. CT volume measurements are accurate and reproducible, particularly for larger structures. Assessment of tumour response using 1D, 2D and 3D measures had limited influence on the classification of treatment response. However, the impact of CT assessment of tumour response using 1D, 2D and 3D measurements on clinical decisions and patient outcome remains to be determined.

Optimization of scanning parameters for CT colonography.

To determine the optimal collimation, pitch and reconstruction interval for CT colonography, 10 spherical polyps between 1 mm and 10 mm diameter and made of tissue equivalent material with a CT number of 40 Hounsfield units (HU) were placed in the colon of an anthropomorphic phantom. The phantom was scanned at slice thicknesses of 3 mm, 5 mm and 7 mm and pitches of 1.0, 1.3, 1.5, 1.7 and 2.0 on an IGE Hispeed advantage system. Images were reconstructed for each scanning parameter at the minimum intervals allowed along the z-axis. The optimum scanning protocol was assessed by measuring maximum contrast between the polyp and air, sensitivity for detection of each polyp along the z-axis, and relative radiation dose. In addition, images were reviewed separately by two radiologists who graded polyp conspicuity as: 0, not seen; 1, faintly seen; 2, well seen. It was found that varying the scanning parameters caused a marked alteration in the maximum contrast between each polyp and air. For example, for the 5 mm polyp, the range of contrasts from best to worst case was 910-490 HU. It was noted that with contrasts of less than 500 HU, polyps were only faintly seen. A slice thickness of 3 mm with a pitch of 2 offers optimal polyp conspicuity with a relatively low radiation dose, we conclude that scanning parameters can be optimized for threshold contrast, radiation dose and subjective conspicuity. We propose an optimal parameter of 3 mm slice thickness and pitch 2.

Renal function after high dose urography in patients with renal failure.

A retrospective study of 40 patients with moderate to severe renal failure who had high dose urography showed that none developed oliguric acute renal failure after the urogram. In 37 patients there was no worsening in renal function attributable to the urogram. This group included five patients in whom renal function was already deteriorating at the time of the urogram. In three patients a transient rise in serum creatinine without oliguria occurred in the week following urography. Differences between the British and North American experience are discussed.

Reproducibility of spin lattice relaxation time (T1) measurement using an 0.08 tesla MD 800 magnetic resonance imager.

The reproducibility of T1 measurements using an MD 800 magnetic resonance imager operating at 0.08 T (3.4 MHz) has been assessed by repeated imaging over a 15-week period of a phantom containing six copper-sulphate solutions of different dilutions. The standard pulse sequence of this scanner with an inversion time of 200 ms and a repetition time of 1 s was used. Reproducibility was excellent for the lower T1 range (less than 350 ms), but greater variability was observed at higher T1 values (greater than 490 ms). A linear relationship between T1 and temperature has been demonstrated and a method for standardising T1 values obtained at different temperatures is described.

In-vivo measurement of spin lattice relaxation time (T1) of bone marrow in healthy volunteers: the effects of age and sex.

Magnetic resonance images of the spine, sternum, femoral heads and upper femoral shafts were obtained from 90 healthy volunteers to determine the normal ranges of spin lattice relaxation time (T1) for different regions of the bone marrow. The influence of age, sex and oral contraceptive usage on bone marrow T1 was assessed. Differences observed between the T1 of the various regions of the bone marrow examined were consistent with the expected distribution of erythropoietic cells and fatty marrow. Bone marrow T1 was found to decrease with age, significantly lower mean T1 values being observed in subjects over 40 years of age than for those in the 20-40 years age group. The mean bone marrow T1 of females in the 20-40 years age group was significantly higher than that for males of comparable age. For subjects over 40 years of age, the difference in bone marrow T1 observed between males and females was not significant. Oral contraceptive usage had no effect on bone marrow T1.