Placental Pathology of Zika Virus: Viral Infection of the Placenta Induces Villous Stromal Macrophage (Hofbauer Cell) Proliferation and Hyperplasia.

CONTEXT: -The placenta is an important component in understanding the fetal response to intrauterine Zika virus infection, but the pathologic changes in this organ remain largely unknown. Hofbauer cells are fetal-derived macrophages normally present in the chorionic villous stroma. They have been implicated in a variety of physiological and pathologic processes, in particular involving infectious agents. OBJECTIVES: -To characterize the fetal and maternal responses and viral localization in the placenta following Zika virus transmission to an 11 weeks' gestation fetus. The clinical course was notable for prolonged viremia in the mother and extensive neuronal necrosis in the fetus. The fetus was delivered at 21 weeks' gestation after pregnancy termination. DESIGN: -The placenta was evaluated by using immunohistochemistry for inflammatory cells (macrophages/monocytes [Hofbauer cells], B and T lymphocytes) and proliferating cells, and an RNA probe to Zika virus. The fetal brain and the placenta were previously found to be positive for Zika virus RNA by reverse transcription-polymerase chain reaction. RESULTS: -The placenta demonstrated prominently enlarged, hydropic chorionic villi with hyperplasia and focal proliferation of Hofbauer cells. The degree of Hofbauer cell hyperplasia gave an exaggerated immature appearance to the villi. No acute or chronic villitis, villous necrosis, remote necroinflammatory abnormalities, chorioamnionitis, funisitis, or hemorrhages were present. An RNA probe to Zika virus was positive in villous stromal cells, presumably Hofbauer cells. CONCLUSIONS: -Zika virus placental infection induces proliferation and prominent hyperplasia of Hofbauer cells in the chorionic villi but does not elicit villous necrosis or a maternal or fetal lymphoplasmacellular or acute inflammatory cell reaction.

Intracardiac tumor causing left-ventricular outflow-tract obstruction in a newborn.

The following report describes the case of newborn girl with an asymptomatic systolic murmur, which on imaging revealed a nearly obstructive mass in the left-ventricular outflow tract. The mass was resected and found to be consistent with a rhabdomyoma. Here, we describe the pathologic and clinical characteristics of this tumor.

Solid pancreatic pseudopapillary tumor managed laparoscopically in adolescents: a case series and review of the literature.

BACKGROUND: Solid pancreatic pseudopapillary tumors make up 1%-3% of all pancreatic tumors, occur predominantly in females, and usually present in the third and fourth decades of life. Less frequently, these tumors may present in children. Complete surgical excision is the treatment of choice with excellent outcomes. Usage of a laparoscopic approach has become more common for adult patients. However, the laparoscopic approach is not routinely used in the pediatric population. MATERIALS AND METHODS: A literature review was performed noting 13 documented cases of solid pancreatic pseudopapillary tumors resected laparoscopically in children. We report our case series of three children with a solid pancreatic pseudopapillary tumor treated through a minimally invasive approach. RESULTS: In the literature, most patients had the tumor in the body or distal pancreas. The most common complication was pancreatic fistula, which was managed with total parenteral nutrition. In addition, there were reports of recurrence after biopsy of the tumor. In our case series 2 of the 3 patients received a splenectomy because of the proximity of the tumor to the spleen. There were no intraoperative or postoperative complications. Follow-up length from 13 to 36 months revealed no evidence of recurrence. CONCLUSIONS: In the pediatric population, solid pancreatic pseudopapillary tumors located in the body or tail of the pancreas can be managed with a laparoscopic distal pancreatectomy.

Hemangioendothelioma: a rare case of a primary intracardiac tumor.

Kaposiform hemangioendothelioma (KH) is a rare tumor of vascular origin that commonly affects the cutaneous tissues of the extremities. It can, however, affect the abdomen, thorax, head, or neck. Compared with juvenile hemangiomas, which tend to regress, KH tumors are locally aggressive and usually persist. Associated morbidity and mortality rates range from 12 to 30 % and typically are related to either compressive effects on surrounding vital structures or effects of the Kasabach-Merritt phenomenon [10, 11, 13]. To our knowledge, this report is the first to describe KH presenting as a primary intracardiac tumor.

Identification of a novel, recurrent SLC44A1-PRKCA fusion in papillary glioneuronal tumor.

Mixed neuronal-glial tumors are rare and challenging to subclassify. One recently recognized variant, papillary glioneuronal tumor (PGNT), is characterized by prominent pseudopapillary structures and glioneuronal elements. We identified a novel translocation, t(9;17)(q31;q24), as the sole karyotypic anomaly in two PGNTs. A fluorescence in situ hybridization (FISH)-based positional cloning strategy revealed SLC44A1, a member of the choline transporter-like protein family, and PRKCA, a protein kinase C family member of serine/threonine-specific protein kinases, as the 9q31 and 17q24 breakpoint candidate genes, respectively. Reverse transcription-polymerase chain reaction (RT-PCR) analysis using a forward primer from SLC44A1 exon 5 and a reverse primer from PRKCA exon 10 confirmed the presence of a SLC44A1-PRKCA fusion product in both tumors. Sequencing of each chimeric transcript uncovered an identical fusion cDNA junction occurring between SLC44A1 exon 15 and PRKCA exon 9. A dual-color breakpoint-spanning probe set custom-designed for interphase cell recognition of the translocation event identified the fusion in a third PGNT. These results suggest that the t(9;17)(q31;q24) with the resultant novel fusion oncogene SLC44A1-PRKCA is the defining molecular feature of PGNT that may be responsible for its pathogenesis. The FISH and RT-PCR assays developed in this study can serve as valuable diagnostic adjuncts for this rare disease entity.

Benign sacrococcygeal neoplasm arising at birth from a giant congenital melanocytic nevus.

Giant congenital melanocytic nevi (CMN) are considered to be premalignant with the highest risk for conversion to melanoma. Solid tumors within giant CMN presenting at birth are relatively unusual, and a variety of malignancies have been reported within these masses. However, the frequency of malignancy in these tumors is unknown. We report the unusual case of a female neonate who was born with 2 large, perianal masses within a giant CMN over her trunk. We resected the larger of the 2 masses because of discomfort and bleeding. The mass consisted of an outgrowth of melanocytes with benign characteristics. The smaller of the 2 masses was managed expectantly and has subsequently decreased in size. We propose that pathologically benign masses within giant CMNs may not require immediate resection. We will discuss the management and pathologic findings of this case and review the literature regarding management of CMN-associated neoplasms arising at birth.

Novel SCN1A mutation in a proband with malignant migrating partial seizures of infancy.

OBJECTIVE: To characterize a novel SCN1A mutation in a proband with malignant migrating partial seizures of infancy. DESIGN: Genomic DNA was isolated from blood and submitted for commercial testing. The identified missense mutation was confirmed in brain DNA obtained at autopsy. Genomic DNA from the brain of the proband was analyzed by comparative genome hybridization, and the coding exons of SCN9A were amplified. Quantitation studies of the mutant transcript were performed. SETTING: Children's National Medical Center and Yale University School of Medicine. PROBAND: A full-term female infant who experienced seizure onset at age 10 weeks, with progression of hemiclonic, apneic, and multifocal migrating partial seizures leading to recurrent status epilepticus and death at age 9 months. MAIN OUTCOME MEASURES: Electroencephalographic and magnetic resonance imaging results, quantitative RNA expression, and secondary mutation test results. RESULTS: The heterozygous missense mutation c.C5006C>A was identified by sequencing genomic DNA from blood and was confirmed in brain DNA. The resulting amino acid substitution p.A1669E alters an evolutionarily conserved residue in an intracellular linker of domain 4 of the SCN1A sodium channel protein Na(v)1.1. The mutant transcript is found to be expressed at levels comparable to the wild-type allele in brain RNA. No variation in copy number was detected in the chromosome region 2q24 containing SCN1A or elsewhere in the genome. No mutations were detected in the linked sodium channel gene SCN9A, which has been reported to act as a modifier of SCN1A mutations. CONCLUSION: This report expands the spectrum of SCN1A epileptic channelopathies to include malignant migrating partial seizures of infancy.

Multiple papillary fibroelastomas of the heart.

We report the case of a 41-year-old woman who presented with extensive papillary fibroelastomas of the heart after multiple previous surgical procedures for hypertrophic cardiomyopathy. This case is significant because of the locally aggressive nature of the cardiac papillary fibroelastoma.

Castleman disease: surgical cure in pediatric patients.

Castleman disease is a rare disorder characterized by lymphoid hyperplasia which rarely manifests in children. We present 2 cases which highlight both histologic variants of this disease, and provide suggestions regarding workup and treatment with the goal of making practitioners aware of Castleman disease in the differential diagnosis of a child presenting with vague symptoms.

Loss of the PTCH1 gene locus in cardiac fibroma.

BACKGROUND: Cardiac fibroma (CF) is a rare benign tumor that is poorly characterized genetically. CF is more commonly encountered in patients with Gorlin syndrome (3%) than the general population. Mutations of the tumor suppressor gene PTCH1 are the underlying cause of Gorlin syndrome. METHODS: Conventional cytogenetic analysis was performed on a peripheral blood and a CF sample from a 2-week-old male. In addition, fluorescence in situ hybridization (FISH) studies were performed to assess the copy number of the PTCH1 gene locus (9q22.3) on metaphase and interphase cells from these same specimens using yeast artificial protein (YAC) probe 891G1 and on representative paraffin-embedded tissue sections of two additional CFs (one arising in a 2-month-old female and the other in a 13-week-old male). None of the patients had Gorlin syndrome. RESULTS: Karyotypically, the following abnormal chromosomal complement was detected in the 2-week-old male's CF: 46,XY,del(9)(q22q34)[15]. FISH studies revealed homozygous loss of the PTCH1 locus in the cytogenetically analyzed CF and in the CF arising in the 13-week-old male. Heterozygous loss of this locus was identified in the remaining CF from the 2-month-old female. A mutational mechanism other than deletion may be responsible for PTCH1 inactivation on the other locus in this latter patient. Conventional cytogenetic and FISH studies of the peripheral blood sample from the 2-week-old male were normal. CONCLUSION: These data support a tumor suppressor gene role for PTCH1 in nonsyndromic or sporadic CFs.

Intracranial leptomeningeal metastasis from thymic carcinoma: case report and review.

BACKGROUND: Thymic carcinoma is an uncommon malignant tumor of the anterior mediastinum. Meningeal metastasis from this type of neoplasm is extraordinarily rare and the prognosis is abysmal. CASE DESCRIPTION: This article presents the case of a 45-year-old man with known metastatic thymic carcinoma who presented with intractable headaches. An MRI scan was highly suggestive of a meningioma, and it was initially suspected that this patient had 2 primary tumors. Surgical resection of the mass both demonstrated a metastatic thymic lesion and ameliorated the patient's quality of life. CONCLUSION: The authors report a case of intracranial meningeal metastasis from a lymphoepithelioma-like poorly differentiated metastatic thymic carcinoma, which was treated by resection and WBRT. A review of the current literature revealed no other cases of this uncommon alhistologic subtype of thymic carcinoma metastatic to the cranium. The incidence, histologic classification of subtypes, and treatment are discussed. This case also illustrates the importance of maintaining a high degree of suspicion for a metastasis in patients with known primary malignancy who present with an MRI highly suspicious for meningioma.

Epstein-Barr virus-associated smooth muscle tumors in ataxia-telangiectasia: a case report and review.

Chromosomal breakage syndromes, including ataxia-telangiectasia (AT), are autosomal recessive disorders in which DNA repair mechanisms are defective resulting in chromosomal instability. Affected individuals are at high risk for developing malignancy because of the widespread resulting cellular effects. One such effect, severe immunosuppression, can permit virally mediated neoplasms to manifest, similar to those seen in acquired immunodeficiency syndrome (AIDS), congenital immune deficiency syndromes, and posttransplant populations. Epstein-Barr virus (EBV) is a common viral agent known to be associated with lymphoid, epithelial, and smooth muscle malignancies in such patients. Although smooth muscle tumors have been reported in patients with AT, their association with EBV has not been evaluated. We present a case of EBV-associated laryngeal leiomyosarcoma and jejunal cellular leiomyoma in a child with AT. This case suggests that the development of neoplasia in patients with chromosomal breakage syndromes may be related to the immunosuppressive consequences of these diseases, and searching for infectious causes (such as EBV) is important.