Successful liver transplantation for non-resectable desmoplastic nested spindle cell tumor complicated by Cushing's syndrome.

Desmoplastic spindle cell tumors of liver are rare tumors of low malignant potential characterized by well-demarcated nests of spindle and epithelioid cells in a dense desmoplastic stroma. While surgery remains the definitive treatment, there have been reports of tumor recurrence locally and metastasis which respond poorly to chemotherapy. Hepatic transplant has been attempted in cases of recurrence or large size of primary tumor. Long-term follow-up and imaging surveillance are required as these tumors have shown a tendency for recurrence many years after initial therapy.

Calcifying nested stromal-epithelial tumor (CNSET) of the liver: a newly recognized entity to be considered in the radiologist's differential diagnosis.

Calcifying nested stromal-epithelial tumor (CNSET), an extremely rare tumor found in the liver, was first described in 2001 by Ishak et al. The characteristic imaging features include large size, well-circumscribed, enhancing mass with calcification. To our knowledge, since 2001, there have been 29 reported. Typically arising from the right hepatic lobe, it is primarily found in children and shows clear predilection for females. Emphasizing imaging, we report a 14-year-old female with Beckwith-Wiedemann syndrome who presented with CNSET.

Pharyngeal hairy polyps: five new cases and review of the literature.

Pharyngeal hairy polyps are rare lesions that present as a pedunculated mass that may arise from the oropharyngeal or nasopharyngeal regions of the pharynx. The mass has the potential to partially or completely obstruct pathways towards the trachea and/or esophagus resulting in respiratory distress and/or feeding difficulties respectively. They have a predilection for female infants of 6:1 with the vast majority of the cases occurring in the infantile period. We report 5 cases of the hairy polyp in female infants, one of which showed unusual presentation since it was diagnosed at ten months of age.

Correlation of the detection of Clostridium difficile toxins in stools and presence of the clostridia in tissues of children.

Clostridium difficile toxin is frequently found in the stool of children; however, pseudomembranous colitis is rare. Studying the usefulness of Clostridium difficile toxin assays in pediatrics is required. We performed a correlation between presence of Clostridium difficile toxin in stool and evidence of Clostridium difficile in gastrointestinal pediatric tissue samples using immunohistochemistry (with a pan-clostridial antibody) and polymerase chain reaction (with primers for toxin genes). We studied 11 patients with a median age of 8 years (range, 4 weeks to 17 years); 4 (36%) were female. The median time between detection of Clostridium difficile toxin in stool and obtaining tissue was 3 days. Ten patients survived. Endoscopy was performed in 8 survivors and showed normal mucosa in 2, pseudomembranes in 2, erythema and friability in 1, aphthae in 1, increased mucous production in 1, and colitis in 1. Two survivors underwent laparotomy for either obstruction or resection of necrotic bowel. Histopathologic studies in these 10 surviving patients showed necrosis in 2 samples, granulomatous inflammation in 1, moderate colitis in 1, and mild to minimal pathology in 7. There was no antigenic or molecular evidence of clostridia in the tissue of these patients. Histopathologic evidence of pseudomembranes and immunohistochemical evidence of clostridia were present in postmortem intestinal tissues of the only patient that died. Our findings indicate that Clostridium difficile toxin in stool does not correlate with the presence of clostridia and may not contribute to pathology in intestinal tissues of children. Clostridial antigens were only observed with histopathologic evidence of pseudomembranes.

Expression of inhibitor-of-apoptosis protein (IAP) livin by neuroblastoma cells: correlation with prognostic factors and outcome.

Livin is a recently identified member of the Inhibitor-of-Apoptosis protein (IAP) family of antiapoptosis proteins, and expression has been reported in melanoma and some types of carcinoma. We evaluated livin expression in paraffin-embedded tumor tissue from 68 patients with neuroblastoma (NB) and 7 NB cell lines by immunoperoxidase using an anti-livin monoclonal antibody. Eighteen (26.5%) of the 68 NB tumor tissues showed high livin expression, 36 (53%) showed low-intermediate expression, and 14 (20.5%) were negative. Similarly, 4 NB cell lines showed high livin expression, and 3 showed intermediate expression. In primary NB tissue, livin was observed mainly in tumor neuropil, an extension of tumor cell cytoplasm, and the cytoplasm itself. By reverse transcriptase-polymerase chain reaction, livin expression was confirmed in all 7 NB lines and in frozen tissue from 1 of 3 primary tumors examined to date, in agreement with immunohistochemical data; both livin alpha and beta isoforms were detected. In the NB cases, we further analyzed the correlation between livin expression and clinical and biological features with established prognostic significance (i.e., age at diagnosis, stage, histology, and MYCN oncogene status), and patients' outcome. Livin expression alone did not appear to have an effect on survival; however, patients with high livin expression and amplified MYCN had significantly decreased survival compared with patients lacking both markers or with either of these markers alone. These results suggest that (a) livin is expressed in primary and cultured neuroblastoma cells and (b) high livin expression may identify a subset of neuroblastoma patients with a particularly poor prognosis among those with MYCN amplified tumors.