1/239. Primitive neuroectodermal tumor in sinonasal region. An elderly woman having a nasal tumor diagnosed as alveolar rhabdomyosarcoma was referred to our hospital. Histological reexamination of the patient revealed that the tumor was composed of lobules of compactly arranged small round atypical cells. The atypical cells contained large oval to round vesicular nuclei, and scanty cytoplasm showing PAS positive glycogen material. The tumor cells were immunohistochemically positive for NSE, S-100 protein and vimentin, but showed negative reaction for myoglobin, desmin, EMA, keratin, LCA, chromogranin and MIC2. Ultrastructurally, the tumor cells contained a few cluster of glycogen particles and less organellae and filaments, and there were no cytoplasmic processes, neurosecretory granules or neurofilaments. Pathological findings suggested primitive neuroectodermal tumor resembling extraskeletal Ewing's sarcoma, but negative reaction for MIC2 immunohistochemically could not ascertain the diagnosis. Location of the tumor and age of the patient of the present case were unusual. ( info) |
| The recently individualized and still incompletely understood family of peripheral neuroectodermal tumors encompasses several tumor types, of which some have a predilection for bone. Immunocytochemical studies are essential and usually provide the diagnosis. A t(11;22)(q24;q12) translocation is present in over 80% of cases. Ewing's sarcoma is now viewed as an undifferentiated form of peripheral neuroectodermal tumor, and both tumors require management with combination chemotherapy plus radiation therapy and/or surgery. Contradictory data have been reported regarding the comparative prognosis of peripheral neuroectodermal tumor and Ewing's sarcoma, indicating a need for further studies in large numbers of patients. We illustrate these points by three case-reports, two in girls diagnosed with a vertebral primary at five and nine years of age, respectively, and one in a man diagnosed with a pelvic primary at 29 years of age. ( info) |
3/239. A novel EWS-ERG rearrangement generating two hybrid mRNAs in a peripheral primitive neuroectodermal tumour (pPNET) with a t(15;22) translocation. The occurrence of a t(15;22) translocation in a peripheral primitive neuroectodermal tumour (pPNET) has been previously reported. Molecular examination revealed the presence in tumour mRNA of two hybrid transcripts containing the 5' portion of the EWS gene fused to the 3' portion of the ERG gene. Sequence analyses indicated that both aberrant mRNAs most likely originated from the same rearrangement, which produced different hybrid isoforms due to the presence of an alternatively spliced exon in the ERG gene. To the authors' knowledge, this is the first report of the detection of two hybrid EWS-ERG mRNAs within the same tumour. ( info) |
4/239. Primary primitive neuroectodermal tumor (PNET) of the kidney: a case report. OBJECTIVES: Primary primitive neuroectodermal tumor (PNET) of the kidney is an extremely rare entity and the case is presented to highlight the histological diagnostic problems. methods AND RESULTS: A 23-year-old female presented with a lump in the left hypochondrium that had appeared 3 months, earlier, which suggested a malignancy on radiological investigation. The nephrectomy specimen revealed a large tumor mass with only a small portion of normal renal parenchyma. histology showed a small cell malignant tumor and the diagnosis of PNET (primary of kidney) and small cell carcinoma were suspected. The tumor showed NSE and vimentin positivity and cytokeratin negativity, which conformed with the diagnosis of PNET. CONCLUSION: The biological behaviour of PNET is more aggressive, with rapid progression and infiltration into the surrounding tissues and distant metastases. Thus it differs from the small renal cell malignancies and hence recognition of this tumor as a distinct entity is essential. ( info) |
5/239. Malignant glial tumor arising from the site of a previous hamartoma/ganglioglioma: coincidence or malignant transformation? Gangliogliomas are generally considered benign tumors. Although more commonly found in the brain, spinal cord ganglioglioma is a well established, albeit infrequent, entity. We describe a 2-decade clinical course of a patient initially diagnosed with a thoracolumbar 'glial-neuronal hamartoma' at age 4. Seventeen years after his first operation, local recurrence was noted. Despite subsequent multiple gross total resections and adjuvant therapy, histologic features became increasingly ominous and ultimately proved fatal. This is an unusual report and histologic presentation of a resected spinal cord ganglioglioma recurring as an anaplastic ependymoma/astrocytoma and subsequently a glioblastoma. It is quite likely that the originally resected ganglioglioma was actually part of a primitive neuroectodermal tumor which had undergone extensive maturation. ( info) |
6/239. Peripheral-type primitive neuroectodermal tumor arising in the tentorium. Case report. The authors report the case of a peripheral primitive neuroectodermal tumor (PNET) arising in the tentorium in a 5-year-old boy who presented with frequent vomiting and mild palsy of the left abducent nerve. Following complete surgical excision of the tumor via a transpetrosal approach, the patient has thus far been disease free for 7 years. The tumor tissue was composed of small cells with uniform round nuclei and minimal identifiable cytoplasm. Homer-Wright rosettes were frequently observed. Immunohistochemical studies demonstrated a positive reaction to HBA-71, which recognizes the cell surface glycoprotein p30/32, a product of the MIC2 gene. Both the clinical and immunohistochemical characteristics of this tumor are consistent with a diagnosis of peripheral PNET, which is genetically distinct from the more common intracranial PNET. ( info) |
7/239. Case of the month: January 1999--fetus with echogenic mass in third ventricle. A 29-week gestational age newborn male infant was found to have an echogenic mass in the 3rd ventricle by prenatal ultrasound 2 weeks prior to delivery. At delivery he was poorly responsive and had hydrocephalus and ascites. A CT scan after birth showed cerebral infarction, amorphous tissue in the left hemisphere and numerous calcifications. Despite supportive treatment he died 4 days after birth. Postmortem examination of the brain revealed marked distortion of the architecture and a supratentorial undifferentiated neoplasm consistent with a PNET. The tumor showed extensive areas of hemorrhage and necrosis and involvement of lateral and third ventricles, brain parenchyma, and meninges. ( info) |
8/239. glioblastoma multiforme in a mature ovarian teratoma with recurring brain tumours. AIMS: We report a case study to highlight the occurrence of glioblastoma multiforme in an ovarian teratoma. methods AND RESULTS: A 10-year-old girl presented with a left frontal lobe primitive neuroectodermal tumour which was successfully treated. After 6 uneventful years, she developed glioblastoma multiforme located posterior to the site of the initial tumour. Six years later, she presented with a mature cystic teratoma containing glioblastoma multiforme. CONCLUSIONS: glioblastoma in an ovarian teratoma is an exceptional event, which might have an initial clinical presentation as a metastatic brain tumour. Alternatively, recurring glial tumours may occur in a genetically predisposed person; the role of radiation and chemotherapy in this context remains to be elucidated. ( info) |
9/239. adult primitive neuroectodermal tumour. A case report and review of the literature. A 19-year-old woman presented with left-sided sensorineural hearing loss. She was found to have a left cerebellopontine angle tumour, thought to be an acoustic neuroma on MRI, and was treated with radiosurgery. There was no evidence of tumour on MRI at 6 months. After 1 year, she was admitted with further neurological symptoms. Repeat MRI showed multiple craniospinal tumours. biopsy of the cerebellar tumour revealed it to be a primitive neuroectodermal tumour (PNET). This is a rare tumour in this age group and its management is discussed. ( info) |
10/239. Oral contraceptives: a cause of hyperbilirubinemia in stem cell transplant patients. Conjugated hyperbilirubinemia in the clinical setting of hematopoietic stem cell transplantation can have multiple etiologies that may prompt various therapeutic interventions. Two patients who received short courses of a high-dose estrogen-progesterone combination to treat breakthrough menstrual bleeding during transplant are reported. Conjugated hyperbilirubinemia developed in both patients within days of beginning therapy and resolved after the ethinyl estradiol and norgestrel (Ovral; Pharmacia and Upjohn, Kalamazoo, MI, U.S.A.) was discontinued. In one of the patients, this occurred on three separate occasions during the course of transplantation. Recognizing the cholestatic effect of estrogens during transplantation may prevent unnecessary alterations in therapy beyond the simple discontinuation of these medications. ( info) |