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W R Welch

Publications and source records attributed to W R Welch.

At least 37 records · Page 2Linked to original sources
PubMed1998

Paraovarian cystadenomas and cystadenofibromas: sonographic characteristics in 14 cases.

PURPOSE: To describe the sonographic features of paraovarian cystadenomas. MATERIALS AND METHODS: We searched the computerized pathology and radiology databases for cases of histopathologically proved paraovarian cystadenomas from January 1993 through December 1996 in which preoperative sonography had also been performed. Fourteen paraovarian cystadenomas or cystadenofibromas were identified in 14 patients aged 20-57 years. Sonographic and pathologic findings were correlated. RESULTS: Three of the masses appeared as simple cysts sonographically. Of the remaining 11 masses, nine had solid nodular areas within the cyst; three had septations; and four had a thick wall, an irregular wall, or both at sonography. At sonography, four masses were thought to arise outside the ovary, four were erroneously thought to arise in the ovary, and the location was uncertain in six. CONCLUSION: Paraovarian cystadenomas are cystic masses that usually contain one or more small solid nodules and occasionally contain septations.

Adenofibroma↗
PubMed1997

Identification of a 1300 kilobase deletion unit on chromosome 7q31.3 in invasive epithelial ovarian carcinomas.

We have used polymerase chain reaction (PCR) amplification of tandem repeats to study the pattern of allelic loss on chromosome 7q31 in invasive epithelial ovarian carcinomas and borderline ovarian tumors. Using 13 primer sets spanning loci from 7q31 to 7q32, 16 borderline and 54 invasive ovarian tumor tissue, together with their corresponding normal tissue, were analysed. Invasive epithelial ovarian tumors demonstrated loss of heterozygosity (LOH) at one or more loci on 7q in 32 of 54 cases (59%). The invasive epithelial ovarian tumors demonstrated the highest percentage of LOH at the loci D7S643 (20 of 40 informative cases, 50%) and GATA44F09 (18 of 42 informative cases, 43%). In contrary, only one borderline ovarian tumor showed LOH at one locus (GATA44F09, one of 14 informative cases, 7%). Our results display a sharp contrast in the pattern of LOH between invasive and borderline ovarian tumors suggesting that allelic loss at chromosome 7q31.3 may be involved in the development and progression of invasive epithelial ovarian tumors but not borderline ovarian tumors. Further analysis of the deletion map for the invasive epithelial ovarian tumors showed two regions likely to harbor ovarian tumor suppressor genes including a novel 1300 kilobase common loss region flanked by GATA44F09 and D7S643.

Alleles↗
PubMed1997

A novel 4-cM minimally deleted region on chromosome 11p15.1 associated with high grade nonmucinous epithelial ovarian carcinomas.

Prior cytogenetic and restriction fragment length polymorphism studies have demonstrated that allelic deletion of chromosome 11p is common in human invasive epithelial ovarian tumors. To construct a highly detailed deletion map of chromosome 11p, we used 13 polymorphic microsatellite CA repeat primers to identify regions harboring potential tumor suppressor genes. Twenty-three of 48 samples (48%) of invasive epithelial ovarian cancer showed LOH involving at least one locus, consistent with prior studies. None of the five mucinous tumors showed allelic deletion at any of the 13 primers, suggesting that loss of heterozygosity at chromosome 11p may not be involved in the pathogenesis of mucinous ovarian cancer. Two separate minimally deleted regions were identified in nonmucinous ovarian cancer. The first is an 11-cM region on chromosome 11pl5.5-15.3 that extends from D11S2071 to D11S988 and includes the HRAS locus. The second is a novel 4-cM region on 11p15.1, defined by marker D11S1310. Deletion of both regions at 11p15.5-15.3 and 11p15.1 is strongly associated with high grade nonmucinous epithelial ovarian cancer.

Chromosome Deletion↗
PubMed1997

The utility of patient age in evaluating prostate cancer.

The utility of age in examining patients for prostate cancer was assessed. Of the 462 patients in the study, 138 had prostate cancer. The age distribution of the patients with cancer was similar to that found in patients with prostate cancer in the US population, and a correlation between age and the serum prostate-specific antigen (PSA) value was noted (r = .4, P < .002). Selection of reference intervals had a significant effect on test performance. Using an interval of 0 to 4.0 ng/mL, sensitivity of the PSA assay was 90% overall and varied from 78% (patients aged 50-59 years) to 94% (patients aged 70-79 years). In contrast, age-adjusted reference ranges yielded corresponding sensitivities of 84%, 78%, and 88%. With a single, fixed reference range, specificity decreased with advancing patient age (P < .001). This trend was eliminated by adjusting the cutoff in different age groups. In addition, age-adjusted reference ranges improved specificity by 10%, and by using the results of examination of a biopsy specimen as the "gold standard," the total number of patients classified correctly by PSA increased from 226 to 250 (49%-54%). For staging before treatment, patient age, clinical stage, and Gleason score were combined to yield a single probability estimate for organ-confined disease (P < .001). The use of age-adjusted reference ranges is supported by this study, which demonstrates that assay efficiency and specificity improve and sensitivity, although decreased overall, becomes more uniform across age groups. In this patient population, age was useful in determining the probability of organ-confined prostate cancer. Use of this model in clinical decision making should await evaluation in a prospective trial.

Age Distribution↗
PubMed1996

Frequent microsatellite instability in epithelial borderline ovarian tumors.

To further define the genetic events that could lead to the development of borderline ovarian tumors (BOTs), we analyzed 13 microsatellite markers on chromosomes 3p and q in 18 BOTs and compared the results to 31 serous invasive epithelia] ovarian cancers (IEOCs). Five of the 18 BOTs showed microsatellite instability (MSI) at one or more loci, compared to only 2 of the 31 IEOCs studied (P < 0.04). In two of these five BOTs, MSI was found in multiple loci. All BOTs with MSI were serous, while none of the mucinous type showed any alteration. Loss of heterozygosity was found in only 1 of the 18 BOTs, but in 12 of the 31 IEOCs (P < 0.01). This first report of a relatively high percentage of MSI in BOTs opens a wide spectrum of new hypotheses for borderline ovarian tumorigenesis as well as several new research avenues.

Base Sequence↗
PubMed1996

Loss of heterozygosity of chromosome 17 in human borderline and invasive epithelial ovarian tumors.

Polymerase chain reaction (PCR) analysis of microsatellite polymorphisms corresponding to four loci which map to chromosome 17p and 11 loci which map to chromosome 17q was performed to screen for loss of heterozygosity (LOH) in paired normal and tumor tissues from 27 cases of borderline epithelial ovarian tumors (BEOT) and 32 cases of invasive epithelial ovarian cancers (IOC). LOH was observed in six of 27 (22%) of the borderline tumors and in 29 of 32 (90%) of the invasive ovarian cancers (P<0.001). At all 15 loci studied, a lower percentage of allelic loss was detected in borderline tumors (0-14%) vs invasive cancer (8-93%). At eight loci this difference was statistically significant. For IOC, one common loss region was identified on chromosome 17p and four distinct common loss regions were on chromosome 17q, which supports the notion that multiple tumor suppressors may reside on chromosome 17 in IOC. These data suggest that LOH on chromosome 17 is an infrequent event in BEOT compared with IOC and therefore may not be important in the distinct pathogenesis of BEOT.

Alleles↗
PubMed1996

A 400 kb novel deletion unit centromeric to the BRCA1 gene in sporadic epithelial ovarian cancer.

Allelic deletions on chromosome 17q21 in sporadic ovarian cancer are common, suggesting that inactivation of a tumor suppressor gene(s) in that region may be important for the etiology of these tumors. The recently identified BRCA1 gene on 17q21, involved in the development of familial breast/ovarian cancer, could be a candidate. However, inactivating mutations on BRCA1 in sporadic ovarian cancer has been rarely described. Furthermore, the potential relationship of BRCA1 gene to ovarian tumors of borderline malignancy remains also unclear. We constructed a highly detailed deletion map of chromosome 17q21 based on PCR amplification of eight polymorphic tandem repeat markers in a 650 kb area including three BRCA1 intragenic markers. DNA from 52 sporadic ovarian cancers and 26 borderline tumors, together with their corresponding normal control tissues were used. Only one borderline tumor showed loss of heterozygosity at one marker, whereas 65% of invasive ovarian cancers displayed allelic loss in at least one of the markers studied. A common deletion unit, located approximately 60kb centromeric to BRCA1, was revealed. These results suggest that inactivation of the BRCA1 gene may not be responsible for the development of borderline ovarian tumors and that another tumor suppressor gene, located centromeric to the BRCA1 gene, may play a role in sporadic ovarian cancer development.

Alleles↗
PubMed1996

Telepathology diagnosis by means of digital still images: an international validation study.

Telepathology affords the means to provide pathological diagnosis and consultation to remote sites. However, before telepathology can become an acceptable medical tool, it will be vital to determine the diagnostic accuracy of this technology. We report the results of a single-blind study of the accuracy of diagnosis performed using computerized still images obtained from a telepathology workstation used in a French telepathology network. Four pathologists, each working alone, reviewed a total of 200 cases of routine surgical pathology (50 cases each), and performed diagnosis based on both computer CD-ROM still images (CD) and conventional glass slides (GS). Concordance between GS and CD diagnosis, as well as accuracy, were determined. Other factors related to performance were also measured, including diagnostic certainty, reasons for uncertainty, and causes of diagnostic error. Overall, there was good agreement between CS and CD diagnosis. There was 87.5% concordance between CS and CD diagnosis, and comparison to consensus (correct) diagnosis showed accuracy of 95.5% and 88.5% for GS and CD diagnosis, respectively. Marked variability in accuracy of CD diagnosis was observed among the four pathologists, and issues related to image selection and/or quality appeared responsible for 60% of the diagnostic errors. The lack of sufficient images and clinical information were frequently cited as reasons for diagnostic uncertainty, as well as feelings of insufficient expertise. It is likely that the opportunity for interaction with the referring pathologist and the use of subspecialty consultants would likely improve the performance of telepathology.

CD-ROM↗
PubMed1996

Localization and characterization of white blood cell populations within the human ovary throughout the menstrual cycle and menopause.

The purpose of this investigation was to localize and characterize white blood cell populations in the human ovary through its physiological life cycle. Ovaries from 30 women of reproductive age and from three post-menopausal women were embedded in paraffin or frozen. Clinical information and pathology review were used to obtain accurate menstrual cycle information and to ensure the absence of ovarian disease. Tissue sections were stained for leukocyte phenotypes and the numbers of white blood cells in the ovary were semiquantitatively assessed by two separate examiners using a 0-3 plus (+) scoring system. Our results demonstrated that macrophages and T lymphocytes were the primary immune cells of the ovary, the concentrations of which were dependent on the location and stage of development of the structures containing leukocytes. Developing follicles contained few (+) macrophages located in the theca, while atretic follicles possessed moderate (+2) numbers in the granulosa and few (+) to moderate (+2) numbers in the theca. Newly formed corpora lutea contained few (+) macrophages, while regressing corpora lutea contained abundant (+3) numbers. Human leukocyte antigen (HLA)-DR positive cells were located predominantly at sites where macrophages were present. T lymphocytes were generally not present in the developing follicle but focal, small (+) numbers were observed in blood vessels of the theca. Atretic follicles contained few (+) T lymphocytes in the granulosa and few (+) to moderate (+2) numbers in the theca. Few (+) T lymphocytes were present in new corpora lutea, while moderate (+2) to abundant (+3) numbers were present in regressing corpora lutea. T lymphocytes at all sites were UCHL1 positive. The CD4 (T helper) to CD8 (T suppressor) ration in the corpus luteum was 1:1. B-lymphocytes and natural killer cells were generally absent in the pre-menopausal ovary. The post-menopausal ovary, in contrast, only contained few (+) macrophages, T lymphocytes and natural killer cells in the stroma. In conclusion, our results indicate that the human ovary is an immunologically dynamic tissue containing activated macrophages and T lymphocytes which provide an anatomical basis for immunoendocrine interactions within the ovary.

Adult↗
PubMed1995

Detailed deletion mapping of chromosome 9p and p16 gene alterations in human borderline and invasive epithelial ovarian tumors.

We used PCR amplification of tandem repeats to study the pattern of allelic loss in borderline and invasive ovarian epithelial tumors using 12 primer pairs to generate a detailed deletion map of chromosome 9p. In the invasive ovarian carcinomas, there were three regions displaying high frequency of loss of heterozygosity (LOH) ranging from 31-38%. In contrast, LOH was a rare event among the borderline ovarian tumors, with one region revealing a rate of 20% and the remaining regions only 0-8% LOH. Therefore, allelic loss does not seem to be important for the development of borderline ovarian tumors. We also examined p16 gene expression and mutations in ovarian cancer cell lines and invasive and borderline ovarian tumor tissues. Southern blot analysis revealed no losses of the p16 gene in either the invasive or borderline ovarian tumors. However, the ovarian carcinoma cell lines showed a 50% homozygous deletion rate. SSCP analysis detected a mobility shift in only one (borderline) tumor. Since the primary invasive ovarian tumors did not show any deletions or mutations, it appears that p16 does not play a role in the pathogenesis of these tumors.

Carrier Proteins↗
PubMed1995

Detailed deletion mapping of chromosome 6q in borderline epithelial ovarian tumors.

We have used PCR amplification of tandem repeats and Southern blot analysis to study the pattern of allelic loss at chromosome 6q in borderline ovarian tumors and compared that with invasive ovarian carcinomas. DNA from 46 borderline ovarian tissues, 20 invasive ovarian tumor tissues, together with corresponding uninvolved (control) tissues was used. The invasive tumors demonstrated the highest percentage of loss of heterozygosity (13 of 45 informative cases, 29%) at the 6q25-27 locus site. In contrast, the borderline ovarian tumors showed only an 11% frequency of loss of heterozygosity (3 of 26). Our results display a sharp contrast in the pattern of loss of heterozygosity between invasive and borderline ovarian tumors and suggest that allelic loss at chromosome 6q may not be involved in the development of borderline ovarian tumors.

Alleles↗
PubMed1995

Evidence for a multifocal origin of papillary serous carcinoma of the peritoneum.

Histopathological evidence suggests that papillary serous carcinoma of the peritoneum (PSCP) may be multifocal in origin. Utilizing a PCR based method to detect tandem repeat polymorphisms in formalin fixed tissue, loss of heterozygosity at eight loci on chromosomes 1, 3, 4, and 17 was studied in six cases of PSCP. Loss of heterozygosity was assessed at between 5 and 11 tumor sites/patient. Allelic losses at 4 loci (1q32-qter, 3p14.3-21.1, 17q12, 17q21.3-23) were noted. Three cases demonstrated a different pattern of allelic loss at various anatomic sites within the same patient. In an additional case, a mutation of the p53 gene, detected by quantitative PCR followed by single-strand conformation polymorphism analysis, was detected in only 2 of 5 tumor sites. The pattern of allelic loss and the mutational pattern of the p53 gene varied at tumor sites within the same patient in 4 of 6 cases of PSCP. These findings are consistent with histopathological evidence that PSCP is multifocal in origin.

Base Sequence↗
PubMed1995

Postmenopausal squamous atypia: a spectrum including "pseudo-koilocytosis".

In addition to typical atrophy, the postmenopausal cervix may exhibit a spectrum of epithelial and cellular alterations, including prominent perinuclear halos, nuclear hyperchromasia, variation in nuclear size, and multinucleation. It has not been determined whether such changes, termed postmenopausal squamous atypia (PSA), represent age-related epithelial disturbances or human papillomavirus (HPV)-related low-grade squamous intraepithelial lesions (condyloma). We surveyed 30 cervical biopsies from 26 women over the age of 50 that contained cytoplasmic halos and a spectrum of nuclear alterations, either alone or in association with atrophy. Twenty-three exhibited epithelium with 2- to 3-fold nuclear enlargement, and 18 had moderate or marked nuclear staining intensity. Eleven had a maximum of one or more multinucleated cells in a high-power field. Despite the nuclear alterations, none of the biopsies were positive for HPV by PCR analysis. This is in contrast to 104 of 141 low- and high-grade squamous intraepithelial lesions from a wide age range of women analyzed in the same manner (P = .000006). Features distinguishing PSA from HPV-associated low-grade squamous intraepithelial lesions (condyloma) included less variation in nuclear size and staining intensity, more finely and evenly distributed nuclear chromatin, and greater uniformity of perinuclear halos in PSA. In menopausal or postmenopausal women, PSA should be excluded when considering the diagnosis of a low-grade squamous intraepithelial lesion, specifically if the diagnosis rests on the interpretation of koilocytotic atypia.

Aged↗
PubMed1994

Characteristics of women with a family history of ovarian cancer. I. Galactose consumption and metabolism.

BACKGROUND: Galactose metabolism may be a risk factor for ovarian cancer based upon evidence that galactose causes ovarian failure and that ovarian cancer arises from premature ovarian failure. This study examines galactose-1-phosphate uridyl transferase (GALT) activity in women with a family history of ovarian cancer (FOC) to determine if low GALT activity occurs in women who are at risk for but in whom ovarian cancer has not yet developed. METHODS: The authors studied 106 premenopausal women (FOC patients) with one primary or two second-degree relatives with ovarian cancer compared with 116 age matched control subjects without a family history of ovarian cancer (FOC controls). All women completed questionnaires and had blood drawn to measure GALT activity and genotype. RESULTS: Mean erythrocyte GALT activity, in micromoles of hexose conversion per hour per gram of hemoglobin was 21.5 in FOC patients, significantly lower than the mean of 23.1 observed in FOC control subjects, (P = 0.001). FOC patients more frequently displayed the Duarte variant of galactosemia as detected by electrophoresis. In a subset of 87 patients and 113 control subjects for whom DNA was available, the allelelic frequency of the Duarte variant based upon molecular genetic detection of the N314D mutation that is associated with the Duarte variant was 15.5% among FOC cases compared with 7.5% among control subjects (P < 0.02). Galactose consumption did not differ between FOC patients and control subjects. CONCLUSION: Galactose metabolism differs between women with and without a family history of ovarian cancer, suggesting that it may be a genetic risk factor for ovarian cancer, possibly mediated through oocyte toxicity from galactose.

Adult↗
PubMed1994

Two-year follow-up of 263 patients with post/perimenopausal vaginal bleeding and negative initial biopsy.

Patients with post- or perimenopausal bleeding (PMB) whose initial endometrial biopsy or dilation and curettage (D&C) reveals benign or insufficient tissue may eventually be diagnosed with endometrial cancer or complex endometrial hyperplasia. We studied 286 consecutive patients with PMB who had either an endometrial biopsy or D&C at Brigham and Women's Hospital during November 1990 to April 1991 and reviewed their subsequent specimens after a minimum of 23 months of follow-up. Of the initial 286 patients with PMB, 6 (2%) had endometrial cancer on their index biopsy, 17 (6%) had complex hyperplasia, and 201 (70%) had other benign findings. Sixty-two (22%) had "tissue insufficient for diagnosis." Excluding the 23 with cancer/complex hyperplasia, there were 263 patients in the cohort, 86 of whom (33%) had further endometrial sampling during the follow-up period. Of these, four (2%) were subsequently found to have a uterine malignancy (2 of the benigns, 2 of the insufficients) and five (2%) were subsequently found to have complex hyperplasia. Of the four patients subsequently found to have cancer, two had stage I adenocarcinoma, one had stage IV adenocarcinoma, and one had stage I high-grade stromal sarcoma.

Aged↗
PubMed1993

Mutation of K-ras protooncogene in human ovarian epithelial tumors of borderline malignancy.

The mutation of K-ras protooncogene was examined in 44 cases of borderline ovarian epithelial tumors and 18 cases of invasive ovarian carcinomas. In borderline tumors, K-ras mutations are a common feature, having been found in 21 of 44 cases (48%). Twenty of the 21 mutations were identified at codon 12, and one was identified at codon 13. A detailed analysis of the mutation pattern of K-ras revealed a close association with the histological cell types of the tumor. Mutation of K-ras was detected at a higher frequency in mucinous borderline tumor (identified in 12 of 19 cases) compared to serous borderline tumor (identified in 9 of 25 cases). K-ras mutation was also detected in invasive mucinous and serous ovarian carcinomas, hence supporting the notion that borderline ovarian tumors may represent a pathological continuum between benign and frankly invasive diseases.

Adenocarcinoma, Mucinous↗
PubMed1993

Molecular genetic evidence of a unifocal origin for human serous ovarian carcinomas.

The hypothesis that ovarian cancer is multifocal in origin was examined using molecular genetic techniques. Patterns of allelic deletion on chromosome 17 were studied in 16 informative cases of Stage III serous epithelial ovarian carcinoma. DNA was extracted from specimens collected from the omentum and both ovaries, and the specific alleles and chromosomal loci involved in the deletion were identified and compared. In all cases, the patterns of allelic deletion were identical for the tumors that had been collected from different sites in the same patients. In addition, 4 of the 16 cases were heterozygous for the hypoxanthine phosphoribosyl transferase (HPRT) gene on the X-chromosome and were examined for methylation status. In all 4, the same parental allele of the HPRT gene was methylated in tumor cells collected from both ovarian and omental sites, suggesting that the patterns of inactivation of the X-chromosome are identical. This pattern of allelic deletion and HPRT-gene methylation in tumor samples collected from different sites implies that ovarian carcinomas have a unifocal origin.

Alleles↗