Malignant rhabdoid tumor of the orbit in an infant.

We present the case of an infant with rapidly progressing orbital tumor that had initial radiological and clinical features of both rhabdomyosarcoma and capillary hemangioma. The patient was eventually diagnosed with malignant rhabdoid tumor of the orbit. We discuss the salient histological and radiological features of our case and review the literature on orbital malignant rhabdoid tumors.

Obstructive sleep apnea syndrome as a rare presentation in a young girl with a central nervous system tumor.

Sleep-related breathing disorders are a common problem in infancy and childhood. The most common type of sleep-related breathing disorder in this age group is obstructive sleep apnea syndrome (OSAS), generally caused by factors affecting airway patency, such as tonsillar hypertrophy or obesity. However, in adults OSAS can also be caused by processes affecting the brainstem, such as central nervous system tumors. This report describes a 2-year-old girl who presented with symptoms of snoring, restless sleep, repeated night-time waking, and apneic events while asleep. She had no comorbidities, and examination revealed normal-sized tonsils. A sleep study demonstrated severe OSAS with an obstructive apnea/hypopnea index of 34. Her OSAS completely resolved on excision of the tumor. The case highlights the importance of neurological examination as part of evaluation of OSAS, especially in cases where tonsils are not enlarged and there are no other risk factors for OSAS. CITATION: Buller F, Kamal MA, Brown SK, et al. Obstructive sleep apnea syndrome as a rare presentation in a young girl with a central nervous system tumor. J Clin Sleep Med. 2022;18(4):1211-1214.

Cutaneous Ewing sarcoma: report of 2 cases and literature review of presentation, treatment, and outcome of 76 other reported cases.

Cutaneous Ewing sarcoma is a rare variant that has been poorly characterized and has no standard therapy. We report 2 patients with cutaneous Ewing sarcoma and review 76 other cases reported in the literature for demographics, presentation, treatment, and outcome. Only 2 patients presented with metastatic disease, and only 8 patients developed metastatic disease. Ninety-one percent of all patients are alive despite wide variations in treatment regimens. On the basis of this summary, treatment consisting of local control with surgery and/or radiation and abbreviated chemotherapy is proposed as a treatment option for this less aggressive Ewing sarcoma.

Thoracic spine Langerhans cell histiocytosis in a child with achondroplasia.

Multifocal bone Langerhans cell histiocytosis (LCH) is usually treated with prednisolone and vinblastine. We present a case conservatively treated with indomethacin with good clinical and radiological response. A 7-year-old achondroplastic boy presented with worsening thoracic back pain and leg weakness. An admission MRI spine showed a pathological T1 vertebrae fracture with posterior soft tissue extension compressing and distorting the spinal cord. A CT guided biopsy revealed an LCH. Steroids were avoided to reduce osteopenia risk and further vertebral fragility. Considering the risk of a thoracic surgical approach in a child with this background, he was managed conservatively with indomethacin and a Sternal Occipital Mandibular Immobilizer (SOMI) Brace. Pain resolved completely within 6 months and the brace was discontinued. Serial follow-up scans showed progressive resolution of the pathological T1 fracture and complete resolution of the spinal cord compression.

The antiapoptotic gene A1/BFL1 is a WT1 target gene that mediates granulocytic differentiation and resistance to chemotherapy.

Previous work has demonstrated that WT1 (-Ex5/-KTS) potentiates granulocyte colony-stimulating factor (G-CSF)-mediated granulocytic differentiation. This WT1 isoform suppresses cyclin E, which may contribute to the prodifferentiation effect by slowing proliferation, but WT1 target genes that affect survival might also be involved. We screened a cDNA array and identified the bCL2 family member A1/BFL1 as a new WT1 target gene in 32D cl3 murine myeloblast cells. Induction of WT1 (-Ex5/-KTS) expression is accompanied by up-regulation of A1 on the cDNA array, and this up-regulation was confirmed by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Moreover, both promoter-reporter assays and chromatin immunoprecipitation assays suggest that this isoform of WT1 activates the promoter directly. Constitutive expression of A1 in 32D cl3 cells induces spontaneous granulocytic differentiation, with both morphologic and cell-surface antigen changes, as well as resistance both to chemotherapy and to withdrawal of interleukin-3 (IL-3). Finally, we note an association between WT1 expression and A1 expression in primary acute myeloid leukemia samples. Taken together, these results demonstrate that A1 is a new WT1 target gene involved in both granulocytic differentiation and resistance to cell death, and suggests that these genes might play an important role in the biology of high-risk leukemias.