GIANT CELL TUMOR OF TENDON SHEATH ARISING IN THE TOE

Giant cell tumor of the tendon sheath (nodular synovitis) is a benign soft tissue tumor, usually affecting older women, that most often occurs in the interphalangeal joints of the fingers. Occurrence is rare in children. We present a 12-year-old boy and a 6-year-old girl with giant cell tumors of tendon sheaths occurring in the toes. The tumor from the 12-year-old demonstrated the cytogenetic finding of t(1;2)(p13;q37), which previously has been associated with giant cell tumor of tendon sheath in adults. Giant cell tumors of the tendon sheath occurring in children have similar histological and cytogenetic features as adults, however, there may be a predilection for lower extremity involvement.     

Giant cell tumor of tendon sheath arising in the toe

Giant cell tumor of the tendon sheath (nodular synovitis) is a benign soft tissue tumor, usually affecting older women, that most often occurs in the interphalangeal joints of the fingers. Occurrence is rare in children. We present a 12-year-old boy and a 6-year-old girl with giant cell tumors of tendon sheaths occurring in the toes. The tumor from the 12-year-old demonstrated the cytogenetic finding of t(1;2)(p13;q37), which previously has been associated with giant cell tumor of tendon sheath in adults. Giant cell tumors of the tendon sheath occurring in children have similar histological and cytogenetic features as adults, however, there may be a predilection for lower extremity involvement.     

Undifferentiated Small Cell Hepatoblastoma with a Unique Chromosomal Translocation: A Case Report

Cytogenetic studies of pediatric tumors have revealed a number of reproducible karyotypic abnormalities, including del(p 13) found in aniridia-Wilms' tumor association, t(8;14) in Burkitt's lymphoma, and t(11;22) in Ewing's sarcoma. To date, no consistent cytogenetic abnormality has been reported in association with hepatoblastoma. We report the case of a 7-month-old male infant with the undifferentiated small cell variant of hepatoblastoma. Immunohistochemistry revealed reactivity with antibodies to cytokeratin and vimentin throughout the tumor. Alpha-fetoprotein, neuron-specific enolase, and S100 stains were negative. Chromosomal analysis of metaphase cells from a culture of tumor tissue revealed a translocation of most of the long arm of chromosome 22 to the distal long arm of chromosome 10.     

Pulmonary blastoma in a neonate: a lesion distinct from pleuropulmonary blastoma with unique cytogenetic features

Pulmonary blastoma is a rare malignant primary lung neoplasm typically seen in adults that accounts for 0.3–1.3% of lung malignancies. It has been categorized as a subtype of sarcomatoid carcinoma according to the current World Health Organization Classification of Lung Tumours and is distinct from the more common pediatric lung tumor pleuropulmonary blastoma. We report a case of neonatal pulmonary blastoma, illustrating the imaging characteristics of this rare tumor. The subject of pediatric lung masses is confusing because the terms pleuropulmonary blastoma and pulmonary blastoma have been used interchangeably in previously reported cases. We recommend use of the current WHO classification to differentiate these lesions as additional cases are described. Additionally, we discuss distinctive cytogenetic features of this case.     

Multifocal tenosynovial giant cell tumors in a child with Noonan syndrome

Noonan syndrome is a genetic disorder with variable expression of distinctive facial features, webbed neck, chest deformity, short stature, cryptorchidism and congenital heart disease. The association of Noonan syndrome and giant cell granulomas of the mandible is widely reported. However, Noonan syndrome may also be associated with single or multifocal tenosynovial giant cell tumors, also referred to as pigmented villonodular synovitis. We report a child with Noonan syndrome, giant cell granulomas of the mandible and synovial and tenosynovial giant cell tumors involving multiple joints and tendon sheaths who was initially misdiagnosed with juvenile idiopathic arthritis. It is important for radiologists to be aware of the association of Noonan syndrome and multifocal giant cell lesions, which can range from the more commonly described giant cell granulomas of the mandible to isolated or multifocal intra- or extra-articular tenosynovial giant cell tumors or a combination of all of these lesions.     

Intrathoracic carcinoma in an 11-year-old girl showing a translocation t(15;19).

We report here a rare case of intrathoracic undifferentiated carcinoma in an 11-year-old girl. The biopsy tissue stained with antibodies against cytokeratin and carcino-embryonic antigen. The same staining was obtained using a cell line, PER-403, which was derived from the tumor. DNA from PER-403 cells was tested for the presence of Epstein-Barr virus genes, yielding a negative result. The cytogenetic analysis found a translocation t(15;19) (p12;q13), which has not previously been described in a carcinoma.     

Classic Adamantinoma with Osteofibrous Dysplasia-like Foci and Secondary Aneurysmal Bone Cyst

Adamantinoma, a rare bone lesion of the tibia and fibula, has two distinct variants, classic adamantinoma and osteofibrous dysplasia-like adamantinoma. Composite lesions have not been described. Aneurysmal bone cyst is a benign cystic lesion which may also occur in the tibia and fibula. We report an unusual case of classic adamantinoma with osteofibrous dysplasia-like areas and foci of secondary aneurysmal bone cyst with prominent giant cells. A lesion was diagnosed in a 17-year-old girl with a 14-year history of a slowly enlarging left tibial mass and increasing deformity. Pathologically, the predominant pattern was classic adamantinoma, with minor foci of osteofibrous dysplasia-like adamantinoma and areas of secondary aneurysmal bone cyst with abundant multinucleated giant cells. We report the clinical, radiologic, and pathologic features of this case, and summarize lesions associated with secondary aneurysmal bone cyst. To our knowledge, the association of adamantinoma with secondary aneurysmal bone cyst has not been previously reported.     

Giant Cell Tumor in the Skull of a 9-year-old Child: Immunohistochemistry to Confirm a Diagnosis Rare for Age and Site

Giant cell tumor of the bone is usually located within the epiphysis of a long bone, the majority of the lesions occurring in the third and fourth decades of life. We report an unusual case of giant cell tumor (GCT) arising in the parietal skull bone of a 9-year-old girl. The tumor exhibited histologic findings typical for GCT, with conspicuous intravascular giant cells. Based on microscopic features, not only conditions like aneurysmal bone cyst or bone changes associated with hyperparathyroidism but also tumors such as chondroblastoma or osteosarcoma had to be considered. Immunohistochemistry revealed strong reactivity of the tumor giant cells and normal bone osteoclasts with CD68 but not Mac-387; tumor stromal cells were uniformly negative for both. The stromal cells exhibited two immunohistochemically distinct phenotypes. One, involving 50-80% of the tumor cells, exhibited negative lysozyme staining with positivity of proliferating cell nuclear antigen (PCNA) in about 30% of the nuclei. The other showed reactivity with lysozyme but negative PCNA staining. Immunohistochemistry thus helped to distinguish chondroblastoma and osteosarcoma, in which lysozyme positivity would reside in macrophages but not within stromal cells. Instead, chondroblastoma would exhibit protein S-100 positivity in the tumor cells. The biological behavior of GCT is difficult to predict based on morphology alone, although the malignant potential seems to rest in the stromal cells rather than the giant cells. Specifically, in reported cases, the intravascular occurrence of giant cells in GCT is not associated with an increased incidence of metastasis.     

Mixed gonadal dysgenesis in a patient with de novo tas(Y;19)(p11.3;q13.4) and 45,X mosaicism

We report a patient with a de novo telomeric association between chromosomes 19 and Y in conjunction with mixed gonadal dysgenesis. The patient was first admitted to the clinic because of abnormal external genitalia. Laparoscopic evaluation revealed (1) a rudimentary uterus, one fallopian tube, and a small gonad resembling an ovary on the right side, and (2) an immature fallopian tube, a vas deferens, and a gonad resembling a testis on the left side. Conventional cytogenetic analysis performed on cultivated peripheral blood cells, and tissue obtained from the phallus and a gonadal structure which resembled a testis revealed two different cell lines with the 46,X,tas (Y;19)(p11.3;q13.4) and 45,X karyotype. Y chromosome microdeletion analysis showed that the patient did not have any genomic deletions in the AZFa, b, c, or SRY regions on the long arm of the Y chromosome. This is the first report of a patient with mixed gonadal dysgenesis that is accompanied by a telomeric association between chromosomes 19 and Y with 45,X mosaicism.     

Wilms tumor,AML and medulloblastoma in a child with cancer prone syndrome of total premature chromatid separation and Fanconi anemia

Wilms tumor (WT) is the most common primary renal tumor in childhood. The occurrence of WT in patients with growth retardation, mental retardation and central nervous system abnormalities in association with premature chromatid separation (PCS) and mosaic variegated aneuploidy has been previously described in only 10 patients. Here we report the very rare occurrence of WT with two other malignancies, acute myeloid leukemia and medulloblastoma in association with chromosomal instability. This is a novel presentation of Fanconi anemia with this cytogenetic abnormality. Pediatr Blood Cancer 2009;53:208–210. © 2009 Wiley‐Liss, Inc.     

Giant cell reparative granuloma of the base of the skull in a 4-month-old infant-CT findings

An unusual case of giant cell reparative granuloma of the base of the skull of a 4-month-old infant is described. Computerized tomography was useful in defining extent of the lesion and soft tissue abnormalities. Differential diagnosis with other giant cell lesions is discussed.     

Abdominal undifferentiated small round cell tumor with unique translocation (X;19)(q13;q13.3)

We describe a male with a large abdominal mass, most likely originating from the liver, with capsule rupture and tumor dissemination into the abdominal cavity. Adherence of the tumor to the diaphragm and lower right colon also were noted. A comprehensive evaluation of the mass revealed no tumor‐defining histopathologic, immunocytochemical, ultrastructural, cytogenetic, or translocation features. The malignant tumor was found to have a novel translocation (X;19)(q13;13.3), which has not been reported in small round cell tumors of childhood or adults. The final diagnosis rendered was an undifferentiated small round cell tumor of uncertain cell of origin. Pediatr Blood Cancer 2010;54:1041–1044 © 2010 Wiley‐Liss, Inc.     

Malignant pigmented clear cell epithelioid cell tumor (PEComa) in an adolescent boy with widespread metastases: a rare entity in this age group

Malignant pigmented clear cell epithelioid cell tumor of the kidney is a rare variant of perivascular epithelioid cells tumors (PEComa) or epithelioid angiomyolipoma (AML). PEComa is characteristically composed purely of epitheloid cells. The fat cells and the blood vessels that are typical of classic AML are absent. Most epithelioid AML cases are benign; however, malignant epithelioid AML of the kidney has been occasionally reported in adults in association with tuberous sclerosis. We report the radiological-pathological features of a malignant pigmented clear cell epithelioid renal tumor in a 15-year-old boy presenting with extensive metastases but without clinical evidence of tuberous sclerosis.     

Congenital renal rhabdoid tumor with placental metastases: immunohistochemistry, cytogenetic, and ultrastructural findings.

Malignant congenital tumors of fetal origin are rare lesions, the most common type being congenital neuroblastoma. Although prenatal diagnosis is possible in large tumors, occasionally the tumor will be diagnosed first by its metastatic involvement of the placenta. Placental metastases can reflect either maternal or fetal primary sites, and each has relatively specific patterns of placental involvement. We describe the clinical and pathologic features of a widely metastatic congenital renal rhabdoid tumor with its placental and autopsy findings, and include the immunohistochemical, cytogenetic, and ultrastructural features. The pathologic features of the placenta in congenital renal rhabdoid tumor with placental metastasis have not been previously described. The examination of the placenta in this case led to the initial diagnosis and obviated the need for additional diagnostic procedures.     

Soft-tissue aneurysmal bone cyst: report of a case with t(5;17)(q33;p13).

We describe a primary aneurysmal bone cyst (ABC) of the soft tissue of the distal thigh in a 10-year-old girl. Radiographs showed an oblong density in the soft tissue that was consistent with hemorrhage or calcification; the underlying bone was unremarkable. Pathologic findings were consistent with myositis ossificans on gross examination, but numerous hemorrhagic cysts were present in the lesion. Histopathologic findings showed features of an ABC. Cytogenetic analysis of the tumor revealed 46,XX,t(5;17)(q33;p13); 17p13 breakpoints have been reported in intraosseous ABC. Thirteen months after diagnosis, the patient had excellent function and no radiologic evidence of recurrent disease. Soft-tissue ABC is a rare, benign lesion that can have a similar radiologic appearance to myositis ossificans but has a histologic appearance identical to that of its intraosseus counterpart.     

Juxtaglomerular cell tumor in an 8-year-old girl

Juxtaglomerular cell tumor (JGCT) is an extremely rare renal neoplasm in the pediatric population. It is considered a benign tumor arising from the juxtaglomerular apparatus of the kidney. JGCT has characteristic clinicopathologic features, but its cytogenetic features are unknown. We report a case of JGCT in an 8-year-old female who presented with severe hypertension, elevated serum renin level, and a well circumscribed tumor in the right kidney. Protogranules of renin was identified in the cytoplasm of the tumor cells by electron microscopic examination. Fluorescence in situ hybridization revealed monosomy of chromosomes X, 6, 9, 11, 15, and 21.     

DISSEMINATED MALIGNANT ECTOMESENCHYMOMA (MEM): Case Report and Review of the Literature

Malignant ectomesenchymoma (MEM) is a rare soft tissue tumor believed to arise from a pluripotent migratory neural crest cell and composed of both a mesenchymal element and a neuroectodermal element. The authors report the case of an 11-month-old male who presented with a local abdominal MEM and systemic metastases into lungs, liver, bones, and bone marrow. This is the first reported case of an MEM with initial bone marrow dissemination. The tumor consisted of a neuroblastoma component and a mesenchymal component with sarcomatous features. Diagnosis and therapy were complicated by the histological heterogeneity of the tumor, which also influenced the clinical appearance and course in this case. A literature search revealed 15 other evaluated cases that arose in soft tissue and had adequate clinicopathologic data. Complete surgical resection was the mainstay of treatment, and chemotherapy also appeared to be important. In all reported patients ( n = 3) with initial metastases or bone marrow dissemination, as in this case, no cure could be achieved. In patients with disseminated MEM, new therapeutic approaches such as high-dose chemotherapy followed by stem cell rescue should be considered, similar to the current strategy in patients with stage IV neuroblastoma or soft tissue sarcoma.     

Plasma cell granuloma of the lung in childhood: Atypical radiologic findings and association with hypertrophic osteoarthropathy

Three cases of pulmonary plasma cell granuloma in the pediatric age group are presented. Although rare, it is the most frequent primary lung tumor in childhood. In two of the cases, there was a close adherence between the tumor and the surrounding mediastinal structures and diaphragm, a very uncommon feature in these tumors. In the other case, plasma cell granuloma of the lung was seen in association with a clinical-radiological picture of hypertrophic osteoarthropathy, which resolved after excision of the mass. Such an association has not, to date, been reported in the literature, and could constitute an additional finding useful in the differential diagnosis of primary lung tumors in childhood. The literature concerning this issue has been reviewed.