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Richard A Prayson

Publications and source records attributed to Richard A Prayson.

82 records · Page 5Linked to original sources
PubMed2002

Brain-invasive solitary fibrous tumor of the meninges: report of a case.

Solitary fibrous tumor is a mesenchymal neoplasm that most commonly arises in the pleura, but also in multiple extrapleural sites including, rarely, the meninges. Immunohistochemical findings facilitate its differentiation from other spindle cell lesions such as fibrous meningioma. Although the great majority of extrapleural solitary fibrous tumors behave in a benign fashion, only rare examples of brain-invasive tumors have been documented. We present a case of a brain-invasive solitary fibrous tumor arising in the meninges of a 40-year-old woman. The tumor was marked by focally prominent hypercellularity, moderate nuclear pleomorphism, and increased mitotic activity. Focal infiltration into the underlying brain parenchyma was observed. The tumor was CD34 positive and EMA negative.

Adult↗
PubMed2002

Rasmussen encephalitis: a clinicopathologic and immunohistochemical study of seven patients.

We retrospectively reviewed the clinicopathologic features and immunohistochemical profiles of 7 patients with Rasmussen encephalitis (age range, 3.5-15 years at surgery). All had medically intractable seizures (6 months' to 7 years' duration); all but 1 developed unilateral hemiparesis. Histologically, all cases were characterized by leptomeningeal and parenchymal perivascular chronic inflammation consisting primarily of T lymphocytes (CD3+, CD5+, CD7+). In all but 1 case, a predominance of CD8+ T-cytotoxic/suppressor lymphoid cells over CD4+ cells was observed. All cases had rare B lymphocytes (CD79a+, CD20+). Rare CD10+ and no CD56+ cells were noted. All cases were marked by diffuse proliferation of microglial cells, highlighted on CD68 immunostaining. Focal microglial nodule formations were observed in 4 cases and focal cortical atrophy in 5 cases. Viral inclusions were not noted. There was no evidence of Epstein-Barr virus by LMP-1 antibody immunostaining. The histologic findings of Rasmussen encephalitis resemble those of viral meningoencephalitis. The pathologicfindings may be only focally present, and missed, if diagnosis is made or confirmed with biopsy alone. Most lymphoid cells have a T-cell immunophenotype, with a predominance of CD8+ cells in most cases.

Adolescent↗
PubMed2002

Chromosome 1p allelic loss by fluorescence in situ hybridization is not observed in dysembryoplastic neuroepithelial tumors.

Differentiation of dysembryoplastic neuroepithelial tumor (DNT) from cystic low-grade oligodendroglioma, particularly in a limited biopsy orfragmented specimen, may be impossible. Research has shown that allelic loss of chromosome 1p is a relatively common finding in oligodendrogliomas. Little is known about chromosome 1p status in DNT. We retrospectively evaluated 14 DNTs for loss of heterozygosity (LOH) on chromosome 1p by fluorescence in situ hybridization (FISH) and compared the results with 1p FISH analysis in 57 low-grade oligodendrogliomas (World Health Organization grade II). The 14 DNTs arose in 8 females and 6 males (mean age, 20.9 years at the time of surgery). All 14 DNTs were 1p intact by FISH analysis. The 57 low-grade oligodendrogliomas arose in 31 males and 26 females (mean age, 43.2 years). LOH on chromosome 1p was present in 31 (54%) of 57 tumors; the remaining 26 tumors were 1p intact. LOH on chromosome 1p is not a feature of DNTs. LOH on chromosome 1p may be a useful differential diagnostic feature (favoring oligodendroglioma) in a subset of cases in which specimen fragmentation or size raises the differential diagnosis of DNT vs oligodendroglioma.

Adolescent↗
PubMed2002

Incidental granulomatous inflammation of the uterus.

BACKGROUND: Granulomas of the uterine corpus have been reported in a variety of pathologic conditions but are relatively rare findings in routine histopathologic material. METHODS: This retrospective clinicopathologic study reviewed patients diagnosed with uterine granulomas between 1980 and 1999 in a tertiary referral center. RESULTS: The study group was comprised of 11 women, ranging in age from 37 to 90 years. All patients had histologically confirmed, non-necrotizing granulomas. The most common symptom prompting biopsy or hysterectomy was abnormal bleeding. Several concomittant histopathologies were noted. Eight of 11 patients had a known history of uterine instrumentation. None of the patients had clinical evidence of sarcoidosis or systemic infection, and stains for microorganisms were negative in all cases. Polarizable or foreign materials were not seen. CONCLUSIONS: Well-formed, non-necrotizing granulomas are an infrequent finding in the uterus. A history of instrumentation may explain the presence of granulomas in a subset of patients.

Adult↗
PubMedDate not supplied

Challenges in the management of sphenoid inverted papilloma.

BACKGROUND: Inverted papilloma (IP) arising in the sphenoid sinus is extremely rare. Management of sphenoid sinus IP is especially challenging because of the paucity of sinonasal symptoms on presentation and the inherent surgical risks associated with the anatomic location of the sphenoid sinus. METHODS: We performed a retrospective review of medical records of all patients with IP arising within the sphenoid sinus. RESULTS: A total of five patients were identified. All patients were managed with endoscopic resection. The most common presenting symptom was headache (three patients). The mean follow-up period was 37.6 months (range, 10-79 months). Two patients with erosive skull base lesions adjacent to the internal carotid artery were managed with a staged endoscopic resection. Only one patient developed a recurrence after 38 months and underwent revision endoscopic resection. CONCLUSION: Endoscopic management of sphenoid IP allows maximal resection with minimal morbidity and facilitates endoscopic postoperative surveillance. Complete preoperative radiological assessment of tumor extent is essential. Preoperative medical therapy can help normalize inflamed mucosa and minimize intraoperative bleeding. For large erosive IP, surgical risks may be minimized by considering a staged resection and using computer-aided surgery.

Adult↗