Use of chest computed tomography in the staging of pediatric Wilms' tumor: interobserver variability and prognostic significance.

PURPOSE: To determine the specificity and prognostic significance of computed tomography (CT) of the chest in pediatric Wilms' tumor. PATIENTS AND METHODS: Patients treated for newly diagnosed Wilms' tumor at St Jude Children's Research Hospital between December 1978 and July 1995 were included in the study if an initial chest radiograph and CT were available and if pulmonary involvement (determined by chest radiographs) was absent. For the 202 patients studied, radiographs and CT scans were reviewed blindly and independently by three experienced radiologists for the presence of pulmonary nodules. Outcome variables consisted of intraobserver variability (in a subsample of 40 cases) and concordance between ratings on radiographs and CT scans (both by McNemar's test), interrater variability (by logistic regression), and the cumulative incidence of pulmonary relapse for patients with and without positive CT scans, by reviewer. RESULTS: As expected, ratings of pulmonary involvement on radiographs were discordant with CT ratings. There was marked variability among reviewers in CT ratings (P = .0001). Of 202 CT scans, 78 were read as positive by at least one reviewer, 41 were rated positive by only one reviewer, 18 by two reviewers, and 19 by all three. Intrarater variability on repeat reviews was not significant. Patients with nodules identified on CT had a significantly higher pulmonary relapse rate when analyzed separately by reviewer. However, for the 14 patients who had pulmonary relapse, CT scans were rated positive by all three reviewers in only five cases and as negative by all three in another five cases. CONCLUSION: The variability in interpretation of chest CT scans in patients with Wilms' tumor limits the predictive utility of these studies. Optimal, standardized techniques and central review are essential if chest CT is to be used for staging in cooperative studies.

CT and MR evaluation of intracranial involvement in pediatric HIV infection: a clinical-imaging correlation.

PURPOSE: To review the cranial CT and MR examinations of 29 children with perinatally transmitted HIV infection and correlate the imaging findings with clinical and pathologic data. METHODS: 28 children were examined with CT, four with MR. RESULTS: CT abnormalities were seen in 25 children studied (89%), including cerebral atrophy (25 children), basal ganglia calcification (10 children), periventricular frontal white matter calcification (four children), cerebellar calcification (one child), white matter low attenuation areas (two children), intracranial hemorrhage (three children) and cerebral infarction (one child). Intracranial calcifications were only seen in association with cerebral atrophy and were never seen prior to 1 year of age. Calcifications in the periventricular white matter or cerebellum were always associated with basal ganglia calcifications. MR abnormalities were seen in all four children studied; cerebral atrophy (four children), areas of high signal intensity in white matter (four children), loss of normal posterior pituitary high signal intensity (one child). Cerebral atrophy appeared to be a nonspecific finding that was seen in some children in the absence of neurologic signs and symptoms. All children with intracranial calcifications had developmental delay. Intracranial hemorrhage was seen in children with severe thrombocytopenia. Focal intracranial infections were unusual and neoplastic lesions were not found. CONCLUSIONS: Cerebral atrophy, basal ganglia calcifications, and focal white matter lesions were the most common abnormalities seen neuroradiologically in our series of HIV-infected children; cerebral atrophy was a nonspecific finding.

MR imaging findings in recurrent primary osseous Ewing sarcoma.

The objective of this study was to determine the value of magnetic resonance (MR) imaging in diagnosing local recurrence of Ewing sarcoma. We retrospectively reviewed radiographs, Tc99m-methylene diphosphonate (MDP) skeletal scintigraphy, computed tomography scans, and MR studies of 11 patients who had local recurrences of osseous Ewing sarcoma following initial responses to chemotherapy and local radiation. The MR images were compared to those of a control group of nine patients who had no evidence of relapse. T1- and T2-weighted MR images identified 9 of the 11 recurrences. Computed tomography was diagnostic in 4 of 6 cases evaluated, Tc99m-MDP bone scintigraphy in 4 of 11 cases, and plain radiographs in 2 of 10. MR findings at relapse included changes in signal intensity, increased extent of abnormal marrow signal on T1- and T2-weighted images, and identification of a new soft tissue mass. These findings suggest that MR imaging is valuable in the routine follow-up of primary osseous Ewing sarcoma.

Fast adipose tissue (FAT) assessment by MRI.

We report a method of fast adipose tissue (FAT) assessment to characterize the quantity, and distribution of abdominal adipose tissue. Whole-volume coverage of the abdomen was obtained using 31 contiguous transverse T(1)-weighted images from 16 obese females. A radiologist manually traced all adipose tissue volumes in the images, while a physiologist used an automated method to measure adipose tissue in a single image at the level of the umbilicus. Automated analysis of the umbilicus-level image was significantly correlated with values obtained by manual analysis of the entire abdomen (p < 0. 001). There was good agreement between the automated umbilicus-level image method and the manual whole abdomen method for subcutaneous adipose tissue (r(2) = 0.958), visceral adipose tissue (r(2) = 0. 753), and total adipose tissue (r(2) = 0.941). The automated method required 6 min vs 2 h for the manual method.

Indications for hemiscrotectomy in the management of genitourinary tumors in children.

In the last 30 years at St Jude Children's Research Hospital, 10 boys have undergone hemiscrotectomy for primary testicular tumors or paratesticular rhabdomyosarcoma. Indications for this procedure were scrotal contamination and positive or uncertain surgical margins. Residual tumor was found in only one specimen. There were four complications in the study group. Two patients had complications directly attributable to the hemiscrotectomy, and in one patient this caused a delay in treatment. Preoperative imaging was performed in three patients. This has not been helpful in evaluating residual masses and is not indicated. Based on the authors' experience and a review of the literature, there are a number of indications for hemiscrotectomy in the management of genitourinary tumors in children. Controversies regarding some of these indications should be discussed with the families of these patients during preoperative counseling.

Cavernous transformation of the portal vein in a child with non-Hodgkin's lymphoma.

We present an 11 year old boy who developed collateral vessels in the portal hepatis with non-visualization of the portal vein 9 months after treatment for large cell lymphoma. This "cavernous transformation of the portal vein" may lead to varices with subsequent gastrointestinal hemorrhage.

Hepatic veno-occlusive disease in children undergoing bone-marrow transplantation: usefulness of sonographic findings.

BACKGROUND: Reports of the usefulness of ultrasonography in the diagnosis of hepatic veno-occlusive disease (HVOD) have presented conflicting results. OBJECTIVE: To determine the usefulness of gray-scale or Doppler ultrasonographic measurements in the diagnosis of HVOD in pediatric patients undergoing BMT. MATERIALS AND METHODS: We prospectively obtained 202 serial sonograms on 48 patients and examined the association between the clinical diagnosis of HVOD (McDonald criteria) and eight ultrasound parameters, including the hepatic artery resistive index (HARI), direction and velocity of portal venous flow, and thickness of the gall bladder wall. RESULTS: HVOD developed in 29 of the 48 patients. The portal venous velocity increased after BMT in the group without HVOD and decreased in the group with HVOD; this difference was significant (P = 0.01). However, there was a great deal of variability in velocity measurements for individual patients. The mean HARI was 0.64 in the group with HVOD and 0.63 in the group without HVOD, and there was no difference between the two groups in the pattern of change in HARI relative to the day of BMT (P = 0.4). There was also no significant difference in thickness of the gallbladder wall between the two groups (P = 0.6). CONCLUSION: No ultrasound parameter studied was as useful as the McDonald criteria for diagnosing HVOD.

Primitive neuroectodermal tumors of the chest wall (Askin tumors): CT and MR findings.

OBJECTIVE: The objective of this study was to describe the CT and MR appearances of primitive neuroectodermal tumors of the thoracopulmonary region (Askin tumor), which typically manifest as large tumors involving the chest wall and pleura. This rare malignant neoplasm, seen predominantly in children and young adults, originates in soft tissues of the chest wall, occasionally in bone, or, rarely, in the periphery of the lung. SUBJECTS AND METHODS: The study group included two boys and six girls, 7-18 years old, with thoracic primitive neuroectodermal tumors who had had CT and MR studies at presentation. In seven of these patients, the preoperative imaging interpretation was compared with surgical observations. RESULTS: Seven tumors were large. Unilateral chest wall involvement was seen in all eight patients, pleural involvement in seven, and rib destruction in five. All tumors were heterogeneous on CT scans and T2-weighted MR images, and seven were heterogenous on T1-weighted MR images. The smallest tumor was homogeneous on T1-weighted MR images. Seven tumors had a signal intensity greater than that of skeletal muscle on T1-weighted MR images, and seven showed hemorrhage or necrosis. Invasion of muscle in the chest wall was noted on MR images in seven patients and on CT scans in four patients. CT scans and MR images showed extension of tumor into adjacent lung in four patients but were indeterminate in three patients. One patient had no extension of tumor into adjacent lung. Pulmonary metastases were noted on MR images in one patient and on CT scans in three patients. CT and MR studies correctly showed pleural (n = 6), rib (n = 4), pericardial (n = 1), diaphragmatic (n = 1), and vertebral/spinal cord (n = 1) involvement, confirmed during surgery. CT and MR scans of five patients imaged before surgery were indeterminate for adjacent lung invasion. CONCLUSION: The described radiologic features of Askin tumors may be useful in deciding when to include this entity in the differential diagnosis. Areas of hemorrhage and necrosis in the large tumors are responsible for their heterogeneous appearance on CT scans and MR images. CT scans and MR images are complementary for determining the extent of disease. MR imaging is informative for determining invasion of chest wall muscle, whereas CT scanning is preferred for detecting small pulmonary metastases. Neither technique is adequate for predicting invasion of adjacent lung.

Hodgkin disease: use of Tl-201 to monitor mediastinal involvement after treatment.

PURPOSE: To compare thallium-201 scintigraphy with gallium-67 scintigraphy in the detection of residual or recurrent mediastinal Hodgkin disease after treatment. MATERIALS AND METHODS: The authors performed planar Ga-67 and Tl-201 scintigraphy in 39 patients aged 7-18 years (27 with mediastinal primary disease) after primary treatment. These scans and those in a control group of 14 patients with newly diagnosed known mediastinal Hodgkin disease were evaluated independently by two radiologists for abnormal mediastinal activity. Results were compared with chest computed tomographic (CT) findings and with the clinical criteria of disease status. Interobserver agreement and consensus agreement on gallium and thallium scan findings were evaluated with the kappa statistic, and the specificity of the two imaging methods was analyzed. RESULTS: All study patients were judged to be free of mediastinal disease with CT and the clinical criteria. Interobserver agreement on findings in the treated and control patients was stronger with gallium scintigraphy (kappa +/- SD = 0.956 +/- 0.044) than with thallium scintigraphy (kappa = 0.638 +/- 0.110). Specificity of ratings based on thallium (85% +/- 6) and gallium (90% +/- 5) scintigraphic findings of mediastinal disease did not differ significantly (P = .48). Specificity improved when the results of the two examinations were combined (97% +/- 2). CONCLUSION: Thallium scintigraphy can help to predict the absence of mediastinal Hodgkin disease after treatment.

Hepatic arterial resistance index--an indicator of diffuse liver disease in children treated with bone marrow transplantation.

AIM: To describe the relationship between the resistance index of the common hepatic artery and liver function tests in children undergoing bone marrow transplantation. MATERIALS AND METHODS: We analysed prospectively the results of 106 Doppler ultrasound examinations of the common hepatic artery from 31 bone marrow transplant patients, 16 of whom had normal liver function. The aetiology of the liver dysfunction in the other 15 patients was veno-occlusive disease (n = 7), unknown (n = 3), hepatic graft-versus-host disease (n = 2), hepatitis (n = 2), or cholestasis (n = 1). We assessed the relationships between the hepatic arterial resistance index (HART) and the results of the serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic-pyruvic transaminase (SGPT), alkaline phosphatase (ALK), lactate dehydrogenase (LDH) and serum albumin (ALB) assays and calculated HARI break-point values that might distinguish patients with liver disease from patients with the normal liver function. RESULTS: The significant break point (P < 0.05) of the HARI was 0.55 for SGOT, SGPT and ALK. LDH was associated with a break point of 0.53. Resistance indices for the common hepatic artery below the break-point values predicted liver dysfunction with specificities of 81%, 80%, 92% and 93%, respectively. There was no significant relationship between liver function tests and ALB levels. CONCLUSION: If below 0.55, the hepatic arterial resistance index is a non-invasive indicator of liver dysfunction in children undergoing bone marrow transplantation.

Inferior vena cava--right atrial tumor thrombus in malignant pelvic bone tumors in children.

Two patients with IVC and right atrial tumor thrombus associated with malignant bone tumors are described. Other tumors such as Wilms', renal cell CA, testicular adrenal and hepatic neoplasms have also been reported to invade the IVC. Ultrasound, CT and MRI are helpful in evaluating the presence of vascular thrombosis as well as its longitudinal extent, and intracardiac involvement.

Imaging features of ovarian metastases from colonic adenocarcinoma in adolescents.

This paper describes the imaging features of ovarian metastases from adenocarcinoma of the colon in adolescent females. We reviewed retrospectively abdominal and pelvic computed tomographic and pelvic ultrasound examinations, histologic slices, and clinical charts of six adolescent females with ovarian metastases secondary to adenocarcinoma of the colon. One patient had ovarian metastasis at presentation and was presumed to have a primary ovarian tumor. The ovarian metastases were either solid (n = 3), complex with both solid and cystic components (n = 2), or multilocular cysts (n = 1). The ovarian lesions were large, ranging from 6 cm to 18 cm in diameter. Colorectal carcinoma in adolescent females is frequently associated with ovarian metastases. One imaging characteristic differs in adult and adolescent ovarian metastases, although they do have features in common: in adolescents, a smaller proportion of colorectal ovarian metastases are multicystic (17%) compared with the adult series (45%). These lesions are frequently large and may be complex, multicystic, or solid. Although it is a rare disease, the differential diagnosis of adnexal masses in adolescent females should include ovarian metastases from adenocarcinoma of the colon.

Veno-occlusive disease of the liver after chemotherapy for rhabdomyosarcoma: case report with a review of the literature.

We describe the case of a 3-year-old girl who developed veno-occlusive disease of the liver while receiving chemotherapy for parameningeal rhabdomyosarcoma. After suffering lethargy and oral mucosal bleeding for one day, the patient exhibited a sudden weight gain and refractoriness to platelet transfusions. Symptoms rapidly worsened with elevation of liver enzymes, bleeding diatheses, and respiratory failure. An ultrasound scan of the liver demonstrated reversed flow in the portal vein. Maximal supportive care, including tracheal intubation and mechanical ventilation, was required. The patient gradually recovered with no respiratory and minimal neurological sequelae. Veno-occlusive disease of the liver should be considered in children receiving chemotherapy who develop weight gain, a sudden drop in platelet count and derangement of liver enzymes. Aggressive supportive measures should be instituted if necessary, as patients surviving the acute phase can expect to make a full recovery.

Fat-saturated contrast-enhanced T1-weighted MRI in evaluation of osteosarcoma and Ewing sarcoma.

To assess contrast-enhanced (C+), fat-saturated (FatSat), T1-weighted (T1W) imaging in the characterization of the soft tissue mass associated with primary bone tumors, we compared it with T2-weighted (T2W) imaging in patients with osteosarcoma (n = 36) and Ewing sarcoma family of tumors (Ewing sarcoma; n = 11). Periosseous tumor compared with normal muscle had greater contrast-to-noise ratio (CNR) on the FatSat T1W C+ image than on T2W for 81% (38/47; P < .0001) of patients. The CNR of periosseous tumor compared with subcutaneous fat was greater on FatSat T1W C+ for 98% (46/47; P < .0001). Radiologists found it easier to evaluate neurovascular bundle proximity to tumor with FatSat T1W C+ images than with T2W for 64% of patients (30/47; P < .0001). They judged FatSat T1W C+ superior to T2W for periosseous tumor conspicuity and visualization of soft tissue necrosis in 62% (29/47; P < .0001). In patients with osteosarcoma or Ewing sarcoma, FatSat T1W C+ imaging may replace T2W imaging for soft tissue mass evaluation, especially if contrast is being used for dynamic enhancement.

Chest radiographic features of thoracic metastatic disease in adolescents with colon cancer.

This study describes chest radiographic features of thoracic metastatic disease (TMD) in patients referred for colon cancer to a pediatric oncology hospital. The study group was comprised of 9 patients (7 males, 2 females, age 13-19 years) with serial chest radiographs demonstrating TMD from colon cancer. All patients had a chest radiograph performed within the 2 months prior to death. The median interval from diagnosis of colon cancer to appearance of radiographic TMD was 3 months. Four of nine patients had TMD at presentation, eight of nine patients within 2 years of diagnosis. All abnormalities progressed on serial radiographs. The median interval from appearance of radiographic abnormalities to death was 2 months. Radiographic findings included pleural effusions (n = 6), lymphadenopathy (n = 5), lymphangitic carcinomatosis (n = 4), solitary pulmonary nodule (n = 2), and lobar atelectasis (n = 1). Five patients with pleural effusions initially had right-sided effusions. Radiographic TMD in adolescents with colon cancer usually occurs within 2 years of diagnosis. Once TMD manifests, the prognosis is dismal. Findings include pleural effusions, lymphadenopathy, lymphangitic carcinomatosis, solitary pulmonary nodules, and lobar atelectasis. We suggest that metastatic colon carcinoma should be included in the differential diagnosis for lymphangitic spread of tumor in adolescents.

Childhood lymphoma: diagnostic accuracy of chest radiography for severe pulmonary complications.

INTRODUCTION: We sought to determine whether chest radiography can be reliably used to distinguish persistent or relapsing pulmonary lymphoma from a variety of infectious and noninfectious pulmonary conditions that can occur in children receiving treatment for lymphoma. METHODS: We studied chest radiographs of 37 patients (30 with non-Hodgkin's lymphoma, and seven with Hodgkin's disease) who died of paediatric lymphoma or of treatment complications. Pulmonary findings at autopsy comprised lung tumour (n = 14), pleural tumour (n = 12), pneumonia (n = 22), adult respiratory distress syndrome (ARDS; n = 16), haemorrhage (n = 27), and infarction (n = 13). Using a 4-point scale and without knowledge of autopsy findings, three radiologists independently rated antemortem radiographs for the presence of pulmonary tumour, pleural tumour, pneumonia in general, pneumonia caused by viral, bacterial, fungal, and protozoan pathogens, ARDS, pulmonary haemorrhage, and pulmonary infarction. Diagnostic accuracy was defined by the area under the receiver-operating-characteristic curve (AZ). RESULTS: Diagnostic accuracy was good for pulmonary tumour (AZ, 0.71 +/- 0.6), protozoan pneumonia (AZ, 0.77 +/- 0.06), and ARDS (AZ, 0.86 +/- 0.07) but poor for all other conditions. The absence of both pleural effusions and mediastinal/right hilar lymphadenopathy was significantly associated (P < or = 0.04) with the absence of lung tumour. DISCUSSION: The pulmonary processes in these patients can all demonstrate diffuse airspace opacification, and many patients had multiple lung abnormalities at autopsy. The radiologist-readers were unable to identify which pulmonary conditions were responsible for radiographic findings in most patients. The readers were able to identify patients who did not have pulmonary lymphoma. If pulmonary involvement with lymphoma is unlikely, bronchoscopy with bronchoalveolar lavage may be sufficient to establish a diagnosis. When pulmonary lymphoma is a clinical consideration, open lung biopsy is usually required for diagnosis.

Childhood leukemia: diagnostic accuracy of bedside chest radiography for severe pulmonary complications.

PURPOSE: To determine the diagnostic accuracy of bedside chest radiography in patients who develop severe pulmonary complications while undergoing therapy for leukemia. MATERIALS AND METHODS: The authors studied 45 patients, aged 21 years and younger, who died of leukemia or of treatment complications and for whom autopsy findings were available. Pulmonary findings at autopsy comprised pneumonia (n = 25), adult respiratory distress syndrome (ARDS) (n = 16), hemorrhage (n = 38), infarction (n = 18), and leukemic cellular infiltration (n = 11). Four radiologists who were unaware of the autopsy diagnoses independently rated antemortem bedside chest radiographs. RESULTS: Diagnostic accuracy for each disease was as follows: ARDS, 0.81 +/- .03 (standard error); all pneumonias, 0.56 +/- .04; hemorrhage, 0.47 +/- .07; infarction, 0.50 +/- .12; and pulmonary leukemic cellular infiltration, 0.38 +/- .12. CONCLUSION: The specific radiographic appearance of ARDS permits excellent diagnostic accuracy.

Magnetic resonance imaging for evaluation of childhood aplastic anemia.

PURPOSE: We prospectively evaluated the ability of magnetic resonance imaging (MRI) of the thoraco-lumbar vertebrae to determine the relative amount of red and fatty marrow in children with aplastic anemia. PATIENTS AND METHODS: Twenty pediatric patients (ages 1-19 years) with aplastic anemia underwent T1-weighted (T1W, n = 31) and short T1 inversion recovery (STIR, n = 30) MRI of the midline sagittal thoraco-lumbar spine. Bone marrow (BM) biopsies from the posterior iliac crest (n = 29) were also performed. All studies were evaluated by blinded observers; MR grading was based on visual inspection of signal intensity. Biopsy-estimated cellularity was compared with T1W and STIR grading when these were performed within 14 days of each other (n = 16). All studies were compared to a simultaneous absolute neutrophil count (ANC), absolute reticulocyte count (ARC), and platelet count. RESULTS: BM cellularity estimated by BM biopsy was significantly associated with STIR grading (p = 0.032, Jonckheere-Terpstra test), as were peripheral ANC (p = 0.044), ARC (p = 0.007), and platelet count (p = 0.003). T1W grade was significantly associated with ANC (P = 0.011) but not ARC (p = 0.053) or platelet count (p = 0.377). Biopsy-estimated cellularity was associated with ANC (p = 0.032) and ARC (p = 0.036), but not platelet count (p = 0.282). CONCLUSION: In childhood aplastic anemia patients, STIR (and, to a lesser extent, T1W) MRI of the thoraco-lumbar spine reflects BM activity, as measured by peripheral blood ANC, ARC, and platelet count, and BM cellularity, as measured by BM biopsy. MRI may thus provide a noninvasive measure of hematopoietic status.