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Biomedical subjects

Kristian T Schafernak

Publications and source records attributed to Kristian T Schafernak.

8 recordsLinked to original sources
PubMed2006

Classification of renal neoplasms based on molecular signatures.

PURPOSE: Gene expression microarray studies have demonstrated distinct molecular signatures for different types of renal neoplasms based on overall gene expression patterns. However, in most of these studies the investigators used renal tumors with defined histology. We analyzed a test set of renal tumors in double-blind fashion using recently established molecular profiles of renal tumors as benchmarks. MATERIALS AND METHODS: A total of 16 consecutive nephrectomies performed for neoplasms at a single urological service were subjected to gene expression profiling using cDNA chips containing 21,632 genes. Analysis was clustered with our previously established molecular profiles of 91 histologically defined kidney neoplasms and comparative genomic microarray analysis while blinded to tumor histology and clinical information. RESULTS: With molecular analysis 9, 4, 2 and 1 tumors were classified as clear cell, papillary RCC, chromophobe RCC, and renal oncocytoma, respectively. Histopathological evaluation was concordant in 14 tumors. One of the 2 tumors with a discrepancy between molecular and pathological diagnoses was composed of oncocytoma and high grade clear cell RCC, and the other was chromophobe RCC that histologically mimicked papillary RCC. CONCLUSIONS: We report the feasibility of the molecular diagnosis and classification of unknown renal neoplasms. Molecular diagnosis appears to be reliable and comparable to the standard of urological pathology. This molecular method may be a potentially useful test for establishing an accurate diagnosis that can impact clinical management.

Carcinoma, Renal Cell↗
PubMed2006

West Nile virus encephalomyelitis with polio-like paralysis & nigral degeneration.

BACKGROUND: Patients infected with West Nile virus (WNV) may develop acute neurologic disease, which can be severe or even fatal, including WNV meningitis, encephalitis, and an irreversible acute flaccid paralysis or poliomyelitis-like syndrome. Movement disorders have also been described. REPORT: We report combined neuronal loss, gliosis, and neurofibrillary tangle formation in the substantia nigra of a 41-year-old man with a history of WNV encephalomyelitis and poliomyelitis-like paralysis. CONCLUSIONS: Clinically our patient did not display parkinsonism, however, it is interesting to speculate whether, in the absence of the residual subacute poliomyelitis-like syndrome, the neuropathologic findings could have eventually evolved clinically into WNV-associated postencephalitic parkinsonism.

Enzyme-Linked Immunosorbent Assay↗
PubMed2006

A granulomatous reaction to Avitene mimicking recurrence of a medulloblastoma. Case report.

Microfibrillar collagen hemostat (MCH), also known by its trade name Avitene, is commonly used to control hemorrhage during neurosurgery. Among the documented complications associated with this agent, a granulomatous foreign body reaction is rare, having been described in the central nervous system in only one previous clinical report. In the present study, the authors report the case of a 3-year-old boy who presented with a lesion which appeared to be the recurrence of a tumor 2 months after he had undergone gross-total resection for a medulloblastoma. The patient underwent resection of the presumed recurrent tumor, but histopathological analysis of the specimen revealed a granulomatous foreign body reaction to MCH and no tumor recurrence. In addition to describing the case, the authors review the surgical literature on foreign body reactions to MCH.

Cerebellar Neoplasms↗
PubMed2003

Fine-needle aspiration of superficial and deeply seated lymph nodes on patients with and without a history of malignancy: review of 439 cases.

This study addresses the utility of fine-needle aspiration (FNA) in assessing lymphadenopathy in patients with and without a previous history of malignancy. We reviewed the FNAs of superficial and deeply seated lymph nodes performed at our institution over a period of 18 yr (1983-2001). Where applicable, we also reviewed and report here the results of subsequent surgical excisional biopsies. We analyzed data from 439 patients, who ranged in age from 1 to 90 yr. The neck and retroperitoneum were the most frequently sampled sites (47% and 25%, respectively). Among the 439 FNAs, adequate material was obtained in 421 cases (96%); the remaining 18 were unsatisfactory (4.1%). Malignant diagnoses were rendered in 330 cases (75% of 439), four were suspicious for lymphoma (0.9%), and 87 were read as reactive lymph nodes or granulomas (20%). The most common malignant cytologic diagnoses from these lymph node FNAs were adenocarcinoma, squamous cell carcinoma, and lymphoma. We compared results between two major groups: patients with a history of malignancy and those without. FNA showed malignancy in 87% of patients with a history of cancer and 41% without such a history. Thirty-three or 10% of patients with a history of malignancy were given a benign diagnosis and follow-up surgical excisional biopsies were performed in nine of these cases. Four of the nine showed low-grade lymphoma. Of the 18 non-diagnostic FNAs, nine came from patients with a history of malignancy and in six of these nine who had a follow-up surgical excisional biopsy the lymph nodes were positive for malignancy. Of the other nine, who had no history of malignancy, only two had follow-up biopsies and both of these were negative. Patients with a history of malignancy are more than twice as likely to show malignancy on lymph node FNA compared to those without such a history (87% vs. 41%). Knowing whether a patient has a history of malignancy provides the appropriate level of suspicion for ordering ancillary investigations or even recommending excisional biopsy for further evaluation.

Biopsy, Fine-Needle↗
PubMedDate not supplied

Cytologic and histologic findings in multiple renal hybrid oncocytic tumors in a patient with Birt-Hogg-Dubé syndrome: a case report.

BACKGROUND: Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant neoplastic syndrome characterized by multiple skin lesions, lung cysts and renal tumors. A variety of histologic types of renal tumors have been reported, including clear cell renal cell carcinoma (RCC), papillary RCC, chromophobe RCC, oncocytoma and a recently described hybrid oncocytic tumor, which is thought to be highly associated with BHD. CASE: We report a case of a 48-year-old woman with BHD who initially presented to our institution with spontaneous pneumothorax and was found to have multiple lung cysts and renal tumors on computed tomography. We describe the fine needle aspiration findings of one of the renal tumors, which was suggestive of so-called hybrid oncocytic tumor. We also describe the gross and histologic findings of the multiple kidney tumors that the patient subsequently had excised. CONCLUSION: When multiple kidney tumors from a single patient appear oncycytic on fine needle aspiration, especially when focal clear cells are present, the possibility of oncocytomas and hybrid tumors associated with BHD must be entertained.

Adenoma, Oxyphilic↗
PubMedDate not supplied

Co-existent crescentic glomerulonephritis and renal amyloidosis: a case report and literature review.

Co-existent crescentic glomerulonephritis and renal amyloidosis have only rarely been reported thus far. To our knowledge, only about eighteen convincing cases (with >50% crescents) have been described, mostly in the context of rheumatoid arthritis. In this report, we add a case from our institution and review the existing literature, including a proposed mechanism of crescent formation in this setting. Although the relationship between crescentic glomerulonephritis, renal amyloidosis, and rheumatoid arthritis needs further investigation, we suggest that one should consider the development of crescentic glomerulonephritis with amyloidosis in patients with long-standing rheumatoid arthritis and worsening renal function.

Amyloidosis↗