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Diagnostic accuracy of self collected vaginal specimens for human papillomavirus compared to clinician collected human papillomavirus specimens: a meta-analysis.

BACKGROUND/OBJECTIVES: Providing summary recommendations regarding self collection of vaginal specimens for human papillomavirus (HPV) testing is difficult owing to the wide range of published estimates for the diagnostic accuracy of this approach. To determine summary estimates from analyses of reported findings of the sensitivity, specificity and summary receiver operating characteristic curves (SROC) for self collected vaginal specimens for HPV testing compared to the reference standard, clinician collected HPV specimens. METHODS: Standard search criteria for a diagnostic systematic review were employed. Eligible studies were combined using a random effects model and summary ROC curves were derived for overall and for specific subgroups. RESULTS: Summary measures were determined from 12 studies. Six studies where patients used Dacron or cotton swabs or cytobrushes to obtain samples were pooled and had an overall sensitivity of 0.74 (95% CI 0.61 to 0.84) and specificity of 0.88 (95% CI 0.83 to 0.92), with diagnostic odds ratio of 22.3 and an area under the curve of 0.91. Self specimens using Dacron or cotton swabs or cytobrushes collected by women enrolled at referral clinics had an overall sensitivity of 0.81 (95% CI 0.65 to 0.91) and specificity of 0.90 (95% CI 0.80 to 0.95). Sensitivity and specificity of tampons ranged from 0.67-0.94 and 0.80-0.85 respectively. CONCLUSIONS: Our findings indicate that the combined sensitivity for HPV-DNA is more than 70% when patients use Dacron swabs, cotton swabs, or cytobrushes to obtain their own vaginal specimens for HPV-DNA evaluation. Self collected HPV-DNA swabs may be an appropriate alternative for low resource settings or in patients reluctant to undergo pelvic examinations.

Area Under Curve↗

Specimen holders for simultaneous critical point drying of multiple biological specimens.

Specimen holders were developed for simultaneous critical point drying of multiple specimens of monolayer cell cultures grown on Leighton tube glass cover slips or for specimens of cells collected on silver or cellulose membrane filters. The use of these multiple specimen holders makes it possible to process several specimens in parallel and thus significantly reduce the time required for handling large numbers of samples and also eliminate the possible variations that occur in processing individual samples one at a time in series.

Cells, Cultured↗

How reliable is histologic examination of bone marrow trephine biopsy specimens for the staging of non-Hodgkin lymphoma? A study of hairy cell leukemia and mantle cell lymphoma involvement of the bone marrow trephine specimen by histologic, immunohistochemical, and polymerase chain reaction techniques.

Analysis of non-Hodgkin lymphoma (NHL) involvement of bone marrow trephine biopsy specimens by morphologic features and immunohistochemistry is often difficult, and the criteria for involvement are ill defined. We compared the morphologic and immunohistochemical analysis of B-cell NHL involvement with immunoglobulin heavy chain gene (IgH) rearrangement analysis by polymerase chain reaction (PCR) amplification of the complementarity determining region 3 (CDR3) in bone marrow biopsy specimens from patients with mantle cell lymphoma (n = 53) or hairy cell leukemia (n = 71). By combing morphologic features and phenotype, 54 specimens were considered positive, 62 negative, and 8 inconclusive. PCR analysis showed clonal IgH rearrangements in 46 positive and 6 inconclusive specimens. No clonal IgH rearrangements were present in 61 negative specimens. The 1 false-positive and most false-negative PCR results were likely due to sampling error or DNA degradation of the fixed tissues. In most cases, bone marrow involvement by NHL can be identified by histologic and immunohistochemical examination. Furthermore, clonality of the B-cell population can be detected by amplification of the IgH CDR3 on DNA extracted from bone marrow trephine biopsy sections, which can be helpful in cases diagnosed as inconclusive.

Bone Marrow Examination↗

Considerations in the design of an environmental specimen bank: experiences of the National Biomonitoring Specimen Bank Program.

Since 1979 the National Institute of Standards and Technology (NIST) has been involved in environmental specimen banking activities as part of the National Biomonitoring Specimen Bank (NBSB). These activities have focused on the development of procedures for the collection, processing, analysis, and long-term storage of a variety of environmental specimens including: human liver, mussels and oysters, fish tissue (liver and muscle), marine mammal tissues (blubber, liver, and kidney), and marine sediments. The experiences of the NBSB can provide valuable information to assist in the design of new specimen bank efforts. Based on the experiences of the NBSB, the issues that should be addressed in the design and operation of a valid specimen bank program are presented.

Animals↗

Grading and staging of bladder carcinoma in transurethral resection specimens. Correlation with 105 matched cystectomy specimens.

We compared the grading and staging of transurethral resection of the bladder (TURB) and cystectomy specimens for 105 patients who underwent radical cystectomy for urothelial carcinoma between 1980 and 1984. Of 105 patients, 96% underwent cystectomy within 100 days of TURB (median interval, 10 days). Grading was performed according to the 1998 World Health Organization/International Society of Urologic Pathology grading system and staging according to the 1997 TNM classification. Histologic grade was low-grade, 13; high-grade, 92 in TURB specimens; low-grade, 17; high-grade, 88 in cystectomy specimens. Pathologic stage was Ta, 15; T1, 55; and T2, 35 in TURB specimens; Ta, 5; T1, 19; T2, 19; T3, 46; and T4, 16 in cystectomy specimens. Histologic grade at TURB was associated with pathologic stage at cystectomy (P < .001). When all advanced-stage (muscle-invasive) carcinomas (pT2 or more) were considered together, 55 patients were understaged by TURB, 4 had higher stage in TURB than in cystectomy, and 46 were the same stage as by cystectomy. Forty-three of 55 patients with stage T1 carcinoma at TURB had advanced-stage carcinoma at cystectomy, including 34 who had extravesicular extension (pT3 or more). We found pathologic understanding by TURB occurs in a significant number of patients with bladder cancer; the newly proposed grading system predicted final pathologic stage.

Adult↗

Detection of human epidermal growth factor receptor 2 protein and gene in fine needle aspiration cytology specimens and tissue sections from invasive breast cancer: can cytology specimens take the place of tissue sections?

Overexpression of HER2 protein and HER2 gene amplification in breast cancer are prognostic factors for the response to specific medical treatments such as trastuzumab, endocrine therapy, and chemotherapy. Whereas HER2 expression and gene amplification are generally examined in tissue sections, we investigated whether specimens from fine needle aspiration cytology (FNAC) are adequate for these analyses. HER2 protein overexpression and HER2 gene amplification were assessed in both FNAC specimens and tissue sections from 58 cases of invasive breast cancer. Immunohistochemistry assay for HER2 protein expression was performed according to the HercepTest protocol, and HER2 gene amplification was examined with the Spot-light CISH (chromogenic in situ hybridization) Detection kit. There was a significant positive correlation between assessments of HER2 protein status in the cytology specimens and tissue sections. The sensitivity, specificity, and accuracy of HER2 gene amplification detection in cytology specimens in relation to those in tissue sections were 84.0% (21/25 cases), 87.9% (29/33 cases), and 86.2% (50/58 cases), respectively. FNAC specimens are suitable for detection of HER2 overexpression and HER2 gene amplification in invasive breast cancer.

Adult↗

[The correlation between preoperative pathologic diagnosis of a biopsy specimen and postoperative pathologic diagnosis of a tissue specimen involving colorectal cancer patients].

An endoscopic biopsy was performed on specimens taken from 374 patients with a large bowel cancer, who had received a colo-rectal resection between 1980 and 1984. An average of three to four biopsy specimens was taken from each patient. The pathological diagnosis of these specimens revealed a carcinoma with an identifiable pathological classification in 280 patients (74.9%), a carcinoma without an identifiable classification in 54 (14.4%), a suspect cancer in 7 (1.9%), and no sign of a cancer in 33 (8.8%). The diagnosis of the 33 cases in which no cancer was detected were adenoma in 11 patients, inflammation in 8, necrosis in 1, and no clear pathological determination in 11. The correspondence rates between a biopsy specimen and a tissue specimen diagnoses were 57.9% in a well differentiated adenocarcinoma; 77.4% in a moderately differentiated adenocarcinoma; 85.5% in a poorly differentiated adenocarcinoma; and 100% in a mucoid carcinoma.

Adenocarcinoma↗

[Comparative histological analysis of needle biopsy specimens, prostatectomized specimens and metastatic lymph nodes in prostatic adenocarcinoma--on the basis of the WHO histological classification].

The histological characteristics were comparatively analyzed among biopsy specimens, surgically removed prostates and metastatic lymph nodes obtained from 60 patients with prostatic adenocarcinoma treated by radical prostatectomy. According to the WHO-Mostifi's classification, the proportion of the 6 histologic components, large and/or small simple glands (LSG), micro-glands (MIC), cribriorm (CRB), fused glands (FUS), medullary/solid (MED) and columns-cords/trabecular (C-C), was determined semiquantitatively. LSG, MIC, and CRB are androgen-sensitive components, while FUS, MED and C-C are androgen-refractory components. The proportions of 5 histologic components excluding MIC were similar in the biopsy and prostate specimens. In 78.3% of the patients, the presence (or absence) of androgen-refactory components in the biopsy specimens coincided with that in the prostate specimens. However, the histologic except for the C-C component. Metastatic lymph nodes contained androgen-refactory components in all cases and tended to have more CRB and FUS and fewer LSG. The histology of the needle biopsy specimens may reflect that of the prostate glands, and may serve as a valuable parameter for determining therapeutic modalities. In addition, androgen-refactory components are frequently present in lymph node metastasis.

Adenocarcinoma↗

NEW TRANSPORT MEDIUM FOR SHIPMENT OF CLINICAL SPECIMENS. I. FECAL SPECIMENS.

Cary, Sylvia G. (Walter Reed Army Institute of Research, Washington, D.C.), and Eugene B Blair. New transport medium for shipment of clinical specimens. I. Fecal specimens. J. Bacteriol. 88:96-98. 1964.-A new transport medium for the collection and shipment of clinical specimens is described. Preliminary studies indicate that, with initial fecal specimens, Salmonella and Shigella can be recovered for as long as 49 days, Vibrio comma for 22 days, and Pasteurella pestis for at least 75 days.

Culture Media↗

The impact of intra-operative specimen radiographs on specimen weights for wide local excision of breast cancer.

The ultimate goal of breast conserving surgery (BCS) is to achieve survival and local control rates similar to those for mastectomy while providing improved cosmetic and functional results. The volume of breast tissue removed is the most significant determinant of the final cosmetic outcome of BCS. We hypothesised that intra-operative specimen radiograph (IOSR) during BCS may guide the surgeon to achieve clear radiographic and histological margins with minimum normal breast tissue excision, thus preserving cosmetic appearance. The aim of this study was to evaluate the effect of introducing the policy of IOSR on the weight of specimens of wide local excision of palpable invasive breast cancer. All consecutive patients who underwent therapeutic wide local excision for palpable invasive breast cancer from 01/01/02 to 31/03/03 were included in this study. A policy of IOSR was introduced in October 2002, thus all BCS done after 01/10/2002 underwent IOSR. The mean (S.D.) specimen weight for the no intra-operative specimen radiograph (NIOSR) group was 74 grams compared to 46 g in the IOSR group, (P = 0.0241, unpaired t-test with Welch's correction) and the mean tumour size for the NIOSR was 23(13)mm and for IOSR was 21(8)mm (P = ns, unpaired t-test with Welch's correction). A histologically clear circumferential margin rate in the IOSR group was 96% compared to 82% in the NIOSR group. Five patients in the IOSR group and 11 in NIOSR group had positive anterior or posterior margin. For these patients no further surgical excision was possible as BCS was performed from skin to pectoral fascia. Therefore a radiation boost was given to the site of excision. Only one patient in the IOSR group needed further breast surgery (mastectomy) for a positive inferior (toward nipple) margin for a mammographically occult tumour, while 11 patients in the NIOSR group required further breast surgery. In conclusion, IOSR is a simple, effective and economical way of assessing adequacy of margins while minimising the breast tissue excised during wide local excision of palpable breast cancers.

Adult↗

Application of the C(18)-carboxypropylbetaine specimen processing method to recovery of Mycobacterium avium subsp. paratuberculosis from ruminant tissue specimens.

The causative agent of Johne's disease is Mycobacterium avium subsp. paratuberculosis. This is a chronic, debilitating gastrointestinal disorder that affects ruminants and is responsible for significant economic loss. The specimen processing method that combines C(18)-carboxypropylbetaine (CB-18) treatment and lytic enzyme decontamination has been shown to improve the diagnosis of mycobacterioses. This processing method was applied to the isolation of M. avium subsp. paratuberculosis from ruminant tissue samples. The BACTEC 12B liquid culture system was used but was supplemented with 1% egg yolk emulsion, 4 microg of mycobactin J, and 0.5% pyruvate (12B/EMP) for use in conjunction with this method. The final concentration of antibiotics used was 10 microg of vancomycin, 30 microg of amphotericin B, and 20 microg of nalidixic acid (VAN) per ml. A 7H10-based solid medium was also used that included mycobactin J, pyruvate, and VAN but excluded the egg yolk emulsion (7H10/MPV). Several M. avium subsp. paratuberculosis isolates were examined during the evaluation of this processing method. It was observed that treatment with lytic enzymes stimulated the growth of M. avium subsp. paratuberculosis; however, the growth of one isolate was markedly inhibited due to the presence of vancomycin. Subsequently, the vancomycin concentration in the VAN formulation was reduced to 2 microg/ml. A blinded panel of 60 previously characterized tissue samples from bovine and bison were then processed and analyzed by smear and culture. Historically, 31 and 37 specimens were classified as positive by histology and culture, respectively. The overall sensitivity and specificity of smear relative to culture following CB-18 processing were 97.6 and 89.5%, respectively. The 12B/EMP/VAN liquid culture system recovered M. avium subsp. paratuberculosis from 39 specimens, whereas 7H10/MPV and Herrold's egg yolk media recovered M. avium subsp. paratuberculosis from 26 and 16 specimens, respectively. The average times to positive were 7.4 +/- 8.3, 29.9 +/- 2.6, and 24 +/- 0 days, respectively. The contamination rates were 4.8, 22.6, and 20.0%, respectively.

Animals↗

Cryo-electron microscopy of vitrified specimens: an approach to the study of bulk specimens.

We are using and developing cryo-electron microscopy of vitrified specimens. Our main interests concern the structure of muscle and muscular components. Micrographs which generally contain periodic features are analyzed by numerical image processing methods. To detect artifacts induced by the electron microscopy techniques, we correlate our results to those obtained by X-ray diffraction. In this paper, we describe our approach to the study of bulk specimens. Vitrification of such specimens is assessed by cryo-X-ray diffraction. Microscopy is done on cryo-substituted specimens.

Animals↗

Theoretical analysis of specimen cooling rate during impact freezing and liquid-jet freezing of freeze-etch specimens.

We have carried out a theoretical analysis of specimen cooling rate under ideal conditions during impact freezing and liquid-jet freezing. The analysis shows that use of liquid helium instead of liquid nitrogen as cooling medium during impact freezing results in an increase in a specimen cooling rate of no more than 30-40%. We have further shown that when both impact freezing and liquid-jet freezing are conducted at liquid nitrogen temperature, the two methods give approximately the same specimen cooling rate under ideal conditions except for a thin outer layer of the specimen. In this region impact freezing yields the highest cooling rate.

Chemical Phenomena↗

Optimization of glycol methacrylate embedding of large specimens in neurological research. Study of rat skull-brain specimens after implantation of polyester meshes.

Advances in neuroscience require better anatomical knowledge of neuronal architecture and structural details. Optimal embedding techniques are the basis for precise morphometric studies in section series as well as for the evaluation of tissue specimens or implants of differing hardness. There are very few methods for preparing large specimens by resin embedding, although resins such as polyethylene glycol (PEG) and methyl methacrylate (MMA) are presently in use. However, these methods have proven to be laborious and sometimes unsatisfactory for serial sectioning. While glycol methacrylate embedding (GMA) is suitable for smaller specimens, it results in inadequate infiltration and polymerization in blocks larger than 1 x 1 x 0.2 cm. We present an improved technique using GMA, which permits both standardized embedding of 4 x 2 x 2 cm blocks and preparation of section series. This method was developed for preserving skull-brain specimens from rats with polyester-mesh implants. The excellent preservation of cellular details allowed the assessment of local tissue reaction to foreign-body material in situ. Advantages of this method are: (1) No toxic catalysts or solvents are used (as opposed to MMA and current GMA processes); (2) Laborious routines in stretching and mounting of sections are not necessary (in contrast to PEG and MMA); (3) No deplastination is required before staining (in contrast to PEG and MMA); (4) Excellent morphologic preservation of various tissue is achieved.

Animals↗

Effect of specimen length: are the mechanics of individual motion segments comparable in functional spinal units and multisegment specimens?

Functional spinal units (FSUs) are frequently used for in vitro mechanical testing. This approach assumes that the mechanical behavior of the FSUs is equivalent to the mechanics of these segments within the intact spine. The purpose of this study was to determine whether normal spinal mechanics are compromised in FSU preparations. Flexion-extension pure-moment flexibility testing was performed on 13 L2-L5 porcine specimens. The moment-angle relationship of the L3/L4 segment was recorded, and then the multisegment specimens were cut down to L3/L4 FSUs and retested. Comparisons of stiffness, range of motion, and laxity zone were made between conditions. The neutral zone and range of motion parameters were significantly larger in the L3/L4 motion segment compared to the L3/L4 segment tested within the multisegment specimen; the stiffness was not significantly different. These differences were attributed to cutting the supraspinous ligament as this ligament spans several vertebral levels. Flexion mechanical tests performed on FSUs should be interpreted cautiously as the biomechanics of FSUs is altered from normal. Although the choice of spine length depends on the experimental purpose, spinal flexion studies should be performed on multisegment specimens to appropriately represent the anatomical boundary conditions.

Animals↗

Detection of Chlamydia trachomatis in genital specimens by the Microtrak direct specimen test.

The conventional cell culture method for detection of Chlamydia trachomatis requires two to six days and is technically difficult to perform. The authors evaluated a new, relatively simple, non-culture method (MicroTrak, Syva Co., Palo Alto, CA) that requires less than one hour to complete. Two hundred fifty-one cervical and 209 male urethral specimens from three Richmond health clinics were read by direct immunofluorescence staining and compared with cell culture technics using iodine staining. Patient specimens were applied directly onto microscope slides (8 mm well) and stained with a fluorescein-labeled monoclonal antibody. Slides were examined for 10-15 minutes at X1,000 using an AO epifluorescent microscope and were considered positive if five or more typical elementary bodies were seen. The sensitivity, specificity, positive and negative predictive values for the direct smear were 89%, 97%, 85%, and 98% for males, and 93%, 96%, 85%, and 98% for females, respectively. The rapid direct specimen test appears to be a satisfactory method for detecting chlamydia in male and female genital specimens.

Cervix Uteri↗

Instrumentation and specimen preparation for electron beam X-ray microanalysis of frozen hydrated bulk specimens.

A cooling chain for the handling of frozen hydrated bulk specimens is described. Use of this method permits the specimen to be kept fully hydrated. After quench freezing, the specimen is transferred to a freeze etch apparatus, freeze fractured, carbon coated and transferred onto the precooled cold stage of the SEM by means of an airlock. The specimen is examined in the secondary electron mode and analysed using an energy dispersive X-ray analyser. The midgut of Chironomus thummi larvae and frog skin epithelium were used to test the performance.

Animals↗

How can the incidence of negative specimens resulting from large loop excision of the cervical transformation zone (LLETZ) be reduced? An analysis of negative LLETZ specimens and development of a predictive model.

OBJECTIVE: To analyse biopsies of large loop excision of the transformation zone of the cervix; to identify factors associated with negative histology; and to develop predictive models in order to reduce the number of negative loop excisions. DESIGN: Retrospective analysis of patient notes and audit database. SETTING: Colposcopy clinic of a large district general hospital in North Staffordshire. POPULATION: Four hundred and fifty-two women who underwent a large loop excision of the transformation zone (LLETZ) procedure for suspected cervical intraepithelial neoplasia. METHODS: Women who underwent a LLETZ procedure were placed in two different groups, one positive for cervical intra epithelial neoplasia and the other negative for cervical intra epithelial neoplasia. Information was obtained on a number of clinical and colposcopic variables. Analysis was undertaken to determine if there were any differences between the two groups. These factors were then identified and three predictive models generated. Receiver-operator characteristic curves were used to assess and test these models. MAIN OUTCOMES MEASURES: To identify factors associated with negative histology on a LLETZ specimen. To predict how to reduce the number of negative LLETZ specimens. RESULTS: Four hundred and fifty-two women underwent a LLETZ procedure, 88 were negative (19%) and 364 were positive (81%). In women who were treated at their first visit, 56/316 (18%) had negative histology. There were significant associations between negative histology in the LLETZ and negative or low grade cytological atypia, negative colposcopic findings and years of age > 50 in both bivariate analysis and stepwise logistic regression. In the predictive models, the sensitivity ranged between 72% and 80%, the specificity 59%-72%, and the area under the receiver-operator characteristic was 0.75-0.77. If we had used the predictor models and managed women with negative or low grade cervical atypia and negative colposcopy findings conservatively, we would have reduced the negative biopsy rate from 19% to 14%, but five cases of high grade disease and 25 cases of low grade disease would have been missed. If we had also included women aged > 50 years in this model, the negative biopsy rate would have dropped from 19% to 15%, with only one case of high grade disease and 11 cases of low grade disease missed. All these women would require continued cytological and colposcopic surveillance. Importantly, no cases of invasion would have been missed. CONCLUSION: Using a predictive model can reduce the number of negative LLETZ specimens, but at the expense of continued cytological and colposcopic surveillance and cannot be recommended in normal practice. This raises the question whether current standards for negative histology in LLETZ specimens are set unrealistically high.

Adolescent↗