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S A Silver

Publications and source records attributed to S A Silver.

26 records · Page 2Linked to original sources
PubMed1994

Composite cytological smears of pelvic lymph nodes at the time of radical prostatectomy to identify nodal metastases.

Many urologists will abort a radical prostatectomy (RP) after intraoperative identification of regional lymph node (LN) metastases because RP in these patients is not curative. Because frozen section techniques are time consuming and incompletely sample LNs, we evaluated the efficacy of performing a composite cytological smear (CCS) by sampling all grossly identifiable LNs. Two hundred and fifty RPs performed from November 1991 to June 1992 yielded on permanent section 33 (+) pelvic lymph node dissections (PLNDs) (6.6%) in 25 RPs (10%). Eleven (33%) of the 33 PLNDs with metastases were grossly suspicious, all were identified by CCS (median percentage of positive LNs per PLND = 33; median size of the largest metastasis = 11 mm). Of the remaining 22 grossly negative PLNDs with tumor, only seven (32%) were detected by CCS (median percentage of positive LNs per PLND = 13; median size of largest metastasis = 3 mm). In the 15 cases missed by CCS the median percentage of positive LNs per PLND was 14, and the median size of the largest metastasis was 1 mm. This method reliably detected LN metastases measuring more than 2 mm as long as the positive LN was grossly recognizable as an LN and thus sampled by CCS. In conclusion, CCS is highly specific but insensitive for the detection of limited numbers of micrometastases, which are the most common type of metastases in patients with low clinical stage disease. A combined technique employing frozen sections on smaller nodes and CCS on larger nodes may be more effective in identifying small metastatic deposits.

Adenocarcinoma↗
PubMed1994

DNA ploidy analysis of pediatric germ cell tumors.

To determine the usefulness of DNA ploidy analysis in the biological assessment of pediatric germ cell tumors (GCTs), paraffin-embedded tissues from primary, recurrent, and metastatic neoplasms in 32 patients under age 18 were analyzed using static image cytometry. Primary sites included testis (eight), ovary (nine), sacrococcygeal region (10), central nervous system (three), and other extragonadal sites (two). The majority of the tumors were endodermal sinus tumors (ESTs) and teratomas. Of 13 teratomas, eight were diploid and five aneuploid. Immature ovarian teratomas of up to Grade II were diploid, whereas all of three Grade III immature teratomas were aneuploid. All sacrococcygeal teratomas, regardless of grade, were diploid; the development of EST in two sacrococcygeal teratomas was associated with the development of aneuploidy. Of 17 endodermal sinus tumors, five were diploid, five aneuploid, and seven tetraploid. All diploid ESTs occurred in the testis or extragonadally in patients 24 mo of age or younger. Infantile testicular ESTs were either tetraploid (one) or diploid (two), and ovarian ESTs were either aneuploid (two) or tetraploid (three). Comparing our data with that available for adult GCTs, we suggest that some pediatric GCTs may be pathogenetically distinct from adult GCTs. Adult testicular GCTs have been shown to be aneuploid, whereas infantile testicular ESTs are often tetraploid or diploid. This suggests a different pathogenesis for these groups of tumors and may explain their biological differences as well. The transformation of a sacrococcygeal teratoma into a malignant EST is poorly understood. Ploidy analysis presented suggests genetic alterations may accompany this transformation.

Adolescent↗
PubMed1993

Adenocarcinoma of the colon simulating primary urinary bladder neoplasia. A report of nine cases.

Nine cases of adenocarcinoma of the colon, secondarily involving the urinary bladder mucosa and histologically mimicking primary bladder neoplasia, are reported. Five patients presented with bladder involvement at the time of diagnosis of colon cancer; four developed vesical lesions 9 to 66 months after resection of their colonic primary. The majority (89%) had genitourinary symptoms at presentation; gastrointestinal manifestations were present in only 60% of those with synchronous colonic involvement. The initial clinical impression, largely based on cystoscopic and radiographic studies, was a bladder primary in four cases and colon cancer in five. Of the former, three (75%) were known to have a history of colon cancer. Histologically, all were enteric-type adenocarcinomas and all had features mimicking a villous adenoma of the bladder. Distinguishing a primary bladder adenocarcinoma from spread of a colonic carcinoma to the bladder may not be possible on histopathologic grounds alone. Consideration should be given to the possibility of an extravesical primary even when symptomatology, cystoscopy, radiographic studies, and histopathology suggest a primary bladder neoplasm.

Adenocarcinoma↗
PubMed1977

Molecular basis for the maximum growth temperature of an obligately psychrophilic yeast, Leucosporidium stokesii.

Cells of the obligately psychrophilic yeast Leucosporidium stokesii were subjected to permissive (15 and 20 degrees C) and restrictive (23 and 25 degrees C) temperatures to determine the event(s) responsible for the low maximum growth temperature of this organism. An investigation of subcellular morphology by nuclear staining revealed that buds formed at 20 degrees C were anucleate but showed nuclear migration within the parent cell. Cells incubated initially at 23 degrees C and then shifted down to a permissive growth temperature of 15 degrees C in the presence of a deoxyribonucleic acid (DNA) synthesis inhibitor, hydroxyurea, confirmed the observation that the anucleate condition of atypical buds was the result of temperature-sensitive DNA synthesis. Concomitantly, the incorporation of labeled adenine into DNA was inhibited at 23 and 25 degrees C. The synthesis of ribonucleic acid, however, was enhanced at 23 degrees C but impaired at 25 degres C. Similarly, protein synthesis was unaffected at either restrictive temperature.

Basidiomycota↗
PubMedDate not supplied

Cerebral cysticercosis mimicking malignant glioma: a case report.

BACKGROUND: Cysticercosis is the most common parasitic infection of the central nervous system in the United States. CASE: A case of cerebral cysticercosis radiographically and pathologically mimicked a high grade glioma. A symptomatic solitary cerebral hemispheric lesion in a child, unknown at the time to have been born in Korea and adopted by U.S. residents, was initially evaluated by stereotactically guided needle biopsy and diagnosed as having malignant glioma in accord with the radiographic impression. The subsequently excised mass revealed cysticercus with an exuberant granulomatous inflammation and gliosis surrounding a fibrous-walled cyst. CONCLUSION: In the setting of a solitary parenchymal cyst, the radiographic differential diagnosis of neurocysticercosis often includes a primary neoplasm. However, to our knowledge, this is the first report of cysticercosis's also simulating a brain neoplasm pathologically.

Biopsy, Needle↗
PubMedDate not supplied

Diagnosis of progressive multifocal leukoencephalopathy by stereotactic brain biopsy utilizing immunohistochemistry and the polymerase chain reaction.

This report describes the diagnosis of progressive multifocal leukoencephalopathy (PML) in nine patients using cytopathologic and histopathologic examination of computed tomographically guided stereotactic brain biopsies in combination with immunostaining for SV-40-related antigen and the polymerase chain reaction (PCR) for the JC virus. In four patients the diagnosis of PML was based on the microscopic appearance of the biopsies and immunostaining for SV-40-related antigen. In one of these patients the diagnosis was also supported by PCR for the JC virus. In two patients whose biopsies were only suggestive of PML, a definitive diagnosis was possible utilizing immunohistochemistry and PCR. In another case the histopathologic features were atypical of PML, and the diagnosis was established with immunostaining and PCR. The diagnosis of PML was established by PCR alone in two patients whose biopsies showed only suggestive or nonspecific findings. We conclude that the accuracy of stereotactic biopsy in the diagnosis of PML is enhanced by using a combination of light microscopy, immunohistochemistry and PCR.

Adult↗