[Nephrogenic tumors]

Nephroblastomas are the most common malignant renal tumors in childhood. According to the guidelines of the SIOP (Société Internationale d'Oncologie Pédiatrique) and GPOH (Gesellschaft für Pädiatrische Onkologie und Hämatologie) pre-operative chemotherapy can be started without histological confirmation and thus initial imaging studies, in particular ultrasound, play an outstanding role for diagnostic purposes.

Fallopian tube cancer associated with paraneoplastic dermatomyositis -- asymptomatic multivisceral exacerbated dermatomyositis mimicking recurrent widespread malignant disease: case report

OBJECTIVE

To report an uncommon case of a recurrent episode of primarily paraneoplastic dermatomyositis which was completely disconnected from the initially triggering malignancy and manifested as a silent pure multivisceral exacerbation.

CASE

A 70-year-old woman presented with a pure multivisceral episode of dermatomyositis without characteristic musculo-cutaneous symptoms one year after successful treatment of fallopian tube carcinoma with complete resolvement of a concomittant paraneoplastic dermatomyositis. The uncommon manifestation of recurrent dermatomyositis involving the lungs, spleen and liver, both adrenal glands and abdominal lymph nodes, mimicked a highly disseminated recurrence of the fallopian tube cancer. Physicians participating in the interdisciplinary tumor board were misled to opt for reinductive chemotherapy. Only histologic diagnosis obtained from multiple biopsies uncovered the inflammatory nature of the disease and spared the patient unneeded chemotherapy.

CONCLUSION

Asymptomatic multivisceral dermatomyositis may mimic metastatic spread of the initially underlying malignancy and may misdirect therapeutic strategies towards inadequate antineoplastic treatment.

[Benign and malignant pulmonary tumors in childhood]

Pulmonary tumors in children are rare. Nevertheless, there are besides malign primary neoplasms and metastases also some benign tumors that the radiologist should know. The identification of some tumors is difficult, since some of them may mimic pulmonary inflammation. The first diagnostic tool is chest radiography. After that, a CT with contrast medium should be performed, if possible a multislice-CT (MSCT). Identification of mediastinal structures is best with MRI.

Blutung in ein kavern�ses retroperitoneales Lymphangiom nach stumpfem Bauchtrauma

The case of a 12-year-old boy with hemorrhage into a previously unknown retroperitoneal lesion following blunt abdominal trauma is reported. Diagnostic work-up of a post-traumatic surgical acute abdomen revealed a giant multicystic tumor in the retroperitoneum, which could be completely removed. Histological examination confirmed the suspected diagnosis of congenital lymphangioma. Attention should be drawn to the possible coincidence of trauma and a preexisting asymptomatic lesion. Knowledge of the characteristic ultrasonographic and computer tomographic features is essential in order to make a correct diagnosis.

Splenosis mimicking tumor recurrence in renal cell carcinoma: detection on selective spleen scintigraphy

A 2-year-old boy had been operated on for a giant renal cell carcinoma including splenectomy because of disrupture of the splenic capsule. During a follow-up examination, 3 nodules were detected by ultrasound in the splenorenal area. This gave reason to suspect tumor recurrence. Considering the possibility of splenosis, a selective spleen scan using denatured red blood cells was performed as a final diagnostic step. This method confirmed the nodules as representing splenic tissue. Splenosis should be included in the differential diagnosis of solid masses in the postsplenectomy patient.

Spiral CT of the lung in children with malignant extra-thoracic tumors: distribution of benign vs malignant pulmonary nodules

The purpose of this paper is to clarify the distribution of benign vs malignant pulmonary nodules which are seen on spiral CT in children with malignant extra-thoracic solid tumors. Seventy-four children with known solid, extra-thoracic tumors underwent spiral CT of the chest. According to the initial and follow-up (interval 9.2+/-4.7 months) findings, the children were graded into four groups: I = normal; II = solitary nodule unchanged at follow-up; III = multiple nodules with one or more than one unchanged at follow-up; and IV = solitary or multiple nodules all changed at follow-up. Nodules without change at follow-up were regarded as benign. Forty-nine children did present with normal pulmonary CT exams. In 7 cases solitary pulmonary nodules were found unchanged (group II) at follow-up and in 2 cases (group III) some of the nodules were stationary. Thus, 12% (9 of 74) presented with at least one pulmonary nodule that did not change at follow-up. Solitary nodules (in groups II and IV) with a diameter <5 mm were in 70 % (7 of 10) unchanged at follow-up and regarded as benign. In children with known solid extra-thoracic tumors at initial presentation, 70% of solitary nodules ( <5 mm) may be benign. To avoid overstaging, smaller solitary nodules must not automatically be regarded as metastases.

Intraabdominal extralobar pulmonary sequestration exhibiting cystic adenomatoid malformation: prenatal diagnosis and characterization of a left suprarenal mass in the newborn

An intraabdominal extrathoracic pulmonary sequestration (IEPS) was detected by prenatal ultrasound in a fetus of 19 weeks' gestation. The well-defined echogenic mass, including multiple cystic areas, was located in the left suprarenal region. Knowledge of the characteristic ultrasound appearance helped to differentiate between neuroblastoma and IEPS before surgical treatment. Histologic examination showed an association between IEPS and features of cystic adenomatoid malformation type 2.

Enteroviral meningoencephalitis in immunocompromised children after matched unrelated donor-bone marrow transplantation

Two children are described who presented with fever and generalized seizures, days 50 and 200, respectively, after matched unrelated donor-bone marrow transplantation. Upon antiepileptic treatment the seizures vanished but somnolence and fever remained. Magnetic resonance imaging (MRI) of the brain was performed and revealed transient asymmetric multifocal hyperintense lesions. Seizures were considered related to infection, and the cyclosporin A (CsA) treatment was not interrupted. Enterovirus was detected by reverse transcriptase-polymerase chain reaction in the spinal fluid of one patient and in the sputum of the other. Both children recovered completely within the next weeks without neurological sequel. This report shows that enteroviral meningoencephalitis can present with seizures during the post-transplant period. It highlights the importance of MRI for neuroimaging and of viral infections as differential diagnosis to CsA neurotoxicity.

[Unexpected regeneration of a congenital unilateral hypoplastic- dysplastic kidney after a contralateral nephrectomy for Wilms tumor]

The congenital hypoplastic-dysplastic kidney is characterized by a significant reduction of renal mass, an abnormal parenchymal differentiation and is associated with anomalies of the whole urinary tract. Not much is known about the ability for regeneration in such a kidney. We report on a 2 year 11 months old boy with an anaplastic Wilms tumor of the left kidney, in whom after tumor-nephrectomy an unexpected functional and sonographically documented morphological regeneration of the contralateral hypoplastic-dysplastic kidney occurred. The regeneration of this kidney is especially notable, because it occurred during nephrotoxic chemotherapy and radiotherapy.

Heterozygous glycine substitution in the COL11A2 gene in the original patient with the Weissenbacher-Zweymüller syndrome demonstrates its identity with heterozygous OSMED (nonocular Stickler syndrome)

The original patient with the Weissenbacher-Zweymüller syndrome was analyzed for mutations in two candidate genes expressed in cartilage (COL2A1 and COL11A2). No mutations were found in the COL2A1 gene but the COL11A2 gene contained a single-base mutation that converted a codon for an obligate glycine to a codon for glutamate at position alpha 2-955 (G955E). The results here and those published previously indicate that the Weissenbacher-Zweymüller syndrome (heterozygous OSMED), nonocular Stickler syndrome, and homozygous OSMED are all caused by mutations in the COL11A2 gene.

[Ewing sarcoma. Diagnostic imaging]

Ewing's sarcoma is a highly malignant neoplasm of the bone whose origin is still uncertain. A strong relationship exists between Ewing's sarcoma and tumors of neural origin (Ewing family of tumors). Ewing's sarcoma must be distinguished from other round-cell tumors like lymphoma and neuroblastoma and also must be differentiated from osteogenic sarcomas. On plain radiographs, Ewing's sarcoma appears as a lytic or mixed lytic-sclerotic, rarely as predominantly sclerotic lesion with margins Lodwick grade III. It is located primarily in the diaphyseal and metadiaphyseal regions of the long bones of the lower extremities. A large soft tissue tumor is usually present. Magnetic resonance imaging is the imaging modality of choice to evaluate the extent of the primary lesion, to monitor the response to neoadjuvant chemotherapy and to follow up non-resected Ewing's sarcomas. Bone scintigraphy is necessary to detect skeletal metastasis, and 201thallium scanning has been shown to be sensitive in the monitoring of treatment response. Today, computed tomography is not longer used to image the tumor site; however, spiral CT of the lungs plays a central role as a staging and follow-up tool.

[Magnetic resonance imaging of breast implants. Significance compared to mammography and ultrasonography]

Magnetic resonance imaging (MRI), mammography and ultrasonography were performed in 44 consecutive women (mean age 45 [29-70] years) with a total of 73 silicone breast implants. The implant had been inserted after mastectomy for cancer in 15 patients, for cosmetic breast augmentation in 29. MRI proved to be superior to the other two imaging modalities with respect to assessing implant content, capsule and surrounding tissues. In 39 patients MRI clearly demarcated the implant from the residual breast tissue. But in four patients the lateral MRI assessment was impaired by phase artefact and in one other by movement artefacts in a restless patient. Implant thickness was underestimated by mammography and ultrasonography compared with MRI. In nine cases mammography showed retromammary parenchyma, while MRI did so in 20. The posterior wall of the implant was visualized by mammography in only one patient, but in all of them by MRI. Ultrasonography failed in all patients to show the entire implant circumference. In three cases MRI was the only imaging method which revealed a defect in the implant capsule with extrusion of silicone.

Early infantile form of Krabbe disease with optic hypertrophy: serial MR examinations and autopsy correlation

The development of white matter lesions in a case of autopsy-proved early infantile form of Krabbe disease was monitored by serial MR examinations. Hypertrophy of the optic nerves was present late in the course of the patient's disease and is a remarkable feature in this case.

[Acute heart failure as an initial symptom of juvenile pheochromocytoma. Glucocorticoid therapy as a possible cause of normotension]

A 13 years old girl was admitted with heart failure. Suspected myocarditis could not be proved. Initially slightly elevated blood pressure values normalized but raised again to hypertensive values when glucocorticoid treatment was discontinued; high blood pressure was associated with tachycardia. Determination of catecholamines and metabolites in urine revealed highly elevated levels mainly of norepinephrine. A phaeochromocytoma could be localized sonographically by angiography and selective determinations of catecholamines in samples taken from different parts of the caval vein. An extraadrenal tumor could be removed and the patient's symptoms ceased.