Overexpression of the transcriptional coregulators C-terminal binding proteins 1 and 2 (CtBP1 and 2) occurs in many human solid tumors and is associated with poor prognosis. CtBP modulates oncogenic gene expression programs and is an emerging drug target, but its oncogenic role is unclear. Consistent with this oncogenic potential, exogenous CtBP2 transformed primary mouse and human cells to anchorage independence similarly to mutant H-Ras. To investigate CtBP’s contribution to in vivo tumorigenesis, Apcmin/+ mice, which succumb to massive intestinal polyposis, were bred to Ctbp2+/− mice. CtBP interacts with adenomatous polyposis coli (APC) protein, and is stabilized in both APC-mutated human colon cancers and Apcmin/+ intestinal polyps. Ctbp2 heterozygosity increased the median survival of Apcmin/+ mice from 21 to 48 weeks, and reduced polyp formation by 90%, with Ctbp2+/− polyps exhibiting reduced levels of β-catenin and its oncogenic transcriptional target, cyclin D1. CtBP’s potential as a therapeutic target was studied by treating Apcmin/+ mice with the CtBP small-molecule inhibitors 4-methylthio-2-oxobutyric acid and 2-hydroxy-imino phenylpyruvic acid, both of which reduced polyposis by more than half compared with vehicle treatment. Phenocopying Ctbp2 deletion, both Ctbp inhibitors caused substantial decreases in the protein level of Ctbp2, as well its oncogenic partner β-catenin, and the effects of the inhibitors on CtBP and β-catenin levels could be modeled in an APC-mutated human colon cancer cell line. CtBP2 is thus a druggable transforming oncoprotein critical for the evolution of neoplasia driven by Apc mutation.

Fibrocartilaginous mesenchymoma of bone is a rare primary neoplasm. Our literature search produced only 12 previously reported cases. Radiographic and computed tomography (CT) findings have been described, but the magnetic resonance imaging (MRI) appearance has not been reported previously. We report a patient with fibrocartilaginous mesenchymoma of the ilium and describe the imaging findings on conventional radiography, bone scan, CT, and MRI.

In conclusion, plain-film radiography and the UGI series are useful, easily obtained tests for screening the pediatric UGI tract and differentiating between medical and surgical disease. Ultrasound continues to develop as an initial test for evaluation of the vomiting infant because of its reliability in diagnosing HPS. Endoscopy remains the superior method for diagnosis of mucosal diseases given the limitations of single-contrast barium studies and the newcomer status of ultrasound. Although scintigraphy is the most sensitive and physiologic imaging method for evaluation of gastroesophageal reflux, the UGI series and endoscopy currently play dominant roles in the evaluation of the child with "significant" GERD. CT, MR imaging, and endoscopy are secondary procedures because of their preparation, sedation, monitoring requirements, and cost. Each modality provides the radiologist a different perspective on pediatric UGI disease and therefore improves our ability to understand and diagnose abnormalities in the pediatric UGI tract.

We report a case of an infant with pulmonary histiocytosis X with punctate thymic calcifications on conventional CT without an anterior mediastinal mass.

The logistic approach in diagnosis of focal nodular hyperplasia (FNH) of the liver is discussed, based on the experience with three children. In only one child could the diagnosis be made without angiography. In that child the combination of hypervascularity on the radionuclide angiogram and uptake of the radiocolloid by Kupffer cells was sufficient for the diagnosis of FNH. If the radionuclide scintigraphy is inconclusive, angiography has to be done to show the typical features of FNH, seen in all three patients. Only if scintigraphy and angiography are not able to differentiate FNH from hepatic adenoma, biopsy or exploratory laparotomy is indicated as a final diagnostic procedure. Ultrasonography or computerized tomography is of value only in screening for hepatic mass lesions.

A 7 year old boy presented with sudden lower extremity paresis six months after resection of a Wilms' tumor. Roentgenologic studies showed destruction of the sixth vertebral body and a thoracic extradural block by an epidural mass subsequently proven to be a solitary Wilms' metastasis.

Intrapericardial teratoma in the newborn is a rare potentially fatal neoplasm. Pre-operative diagnosis depends upon recognition of specific radiographic and echocardiographic findings in a newborn with a large cardiothymic image and pericardial effusion. Surgical intervention is usually curative whereas undiagnosed intrapericardial teratoma is often fatal.

HistoryA 6-year-old boy had been referred at age 22 months for evaluation of a grade 2/6 systolic ejection murmur at the upper right sternal border. Cardiac catheterization showed mild pulmonic valvular stenosis, with main pulmonary artery pressure of 35/12 mm Hg and right ventricular pressure of 32/5 mm Hg. Cardiovascular history was negative for tachypnea, cyanosis, or squatting.DiagnosisCongenital absence of the left pulmonary artery.CommentThe chest roentgenogram (Fig 1) shows the heart and mediastinal structures displaced into the smaller left hemithorax. The left hilum appears small, and pulmonary vascularity is slightly diminished on the affected side. Cardiac size is within normal limits, but a right-sided aortic arch is noted. Pulmonary angiography (Fig 2) illustrates absence of the left pulmonary artery. Aortic angiography (Fig 3) demonstrates a right-sided aortic arch with bronchial arterial collateral supply to the left lung. No additional cardiovascular anomalies were shown. Pulmonary vascular

Splenic hamartoma is a benign, primary neoplasm which usually causes a mass in the left upper quadrant of the abdomen. If radionuclide studies show a space-occupying lesion in the spleen that appears solid on the ultrasonogram, and selective abdominal arteriography reveals a richly vascular splenic tumor, hamartoma of the spleen should be the preoperative diagnosis.

The case of a three-year-old child with facial paralysis due to a lesion within the internal auditory canal is reported. Radiographic studies delineated and localized the mass which proved to be an arachnoid cyst. The etiology and differential diagnosis of facial paralysis in children are discussed and correlated with facial nerve anatomy.