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Three-dimensional reconstruction of the ankle by means of ultrathin slice plastination.

Computerized reconstruction of anatomical structures is becoming very useful for developing anatomical teaching modules and animations. Although databases exist consisting of serial sections derived from frozen cadaver material, plastination represents an alternate method for developing anatomical data useful for computerized reconstruction. Plastination is used as an excellent tool for studying different anatomical and clinical questions. The sheet plastination technique is unique because it offers the possibility to produce transparent slices series, which can easily be processed morphometrically. The purpose of this study was to describe a method for developing a computerized model of the human ankle using plastinated slices. This method could be applied to reconstruct any desired region of the human body.A human ankle was obtained, plastinated, sectioned, and subjected to 3D computerized reconstruction using WinSURF modeling system (SURFdriver Software). Qualitative observations revealed that the morphological features of the model were consistent with those displayed by typical cadaveric specimens. Morphometric analysis indicated that the model did not significantly differ from a sample of cadaveric specimens. These data support the use of plastinates for generating tissues sections useful for 3D computerized modeling.

Ankle↗

Cytology of desmoplastic small round cell tumor.

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a high-grade malignant tumor that has a predilection for adolescent males and usually affects the abdominal cavity. The cytology literature regarding DSRCT, including aspirates and ascitic fluid, is limited. To the authors' knowledge, findings in ThinPrep slides have not been described previously. METHODS: Seven cytologic specimens from five patients with histologically confirmed DSRCT were reviewed. Five specimens were fine-needle aspiration biopsies (FNABs), (liver, flank soft tissue, abdomen, and two resected colons [pericolic]) and two specimens were ascitic fluid. Cytologic features were studied in ThinPrep slides and direct smears, which included hematoxylin and eosin, Papanicolaou, and Quik-Dip stains. RESULTS: All specimens showed moderate to high cellularity. The tumor cells were arranged singly and in clusters. The cells demonstrated high nuclear/cytoplasmic ratios, granular chromatin reminiscent of small cell carcinoma, usually inconspicuous nucleoli, smooth to irregular nuclear membranes, and frequent nuclear molding. The cytoplasm was scant to moderate, pale blue, and occasionally vacuolated. Pseudorosettes were observed in six specimens. One ThinPrep slide and the direct smears contained cells with perinuclear, cytoplasmic densities. Stromal fragments were present in the direct smears but were uncommon in ThinPrep. Three specimens were diagnosed as being consistent with DSRCT. Two specimens were diagnosed as malignant small cell tumor. Molecular studies performed on histologic material in four cases confirmed the presence of the diagnostic translocation, t(11;22)(p13;q12). CONCLUSIONS: DSRCT may be diagnosed accurately in cytology specimens. Characteristic cytologic features include granular chromatin, smooth to irregular nuclear membranes, nuclear molding, cytoplasmic vacuoles, pseudorosettes, and metachromatic stroma. Cytoplasmic densities may be observed in direct smears and ThinPrep slides.

Abdominal Neoplasms↗

Breast ductal carcinoma in situ with microinvasion: a definition supported by a long-term study of 1248 serially sectioned ductal carcinomas.

BACKGROUND: The significance of microinvasion is still debated and clinical management is controversial. The authors defined ductal carcinoma in situ with microinvasion (DCIS-MI) as DCIS with infiltration of the periductal stroma by a few tumor cells, singly (type 1) or in clusters (type 2). With this definition, the authors attempted to evaluate the clinical significance of microinvasion. METHODS: The authors compared the clinical, pathologic features, and survival (median follow-up, 7.3 years) of 1248 patients with, respectively, DCIS (722 patients), DCIS-MI with microinvasion type 1 and type 2 (243 patients), and invasive ductal carcinoma in situ with a predominant DCIS component greater than or equal to 80% of the tumor (IDC-DCIS, 283 patients). RESULTS: Microinvasion was associated with DCIS histologic type, grade, and extent (respectively, P < 10(-8), P < 10(-3), P < 10(-4)). Axillary lymph node metastases were observed in a few patients with DCIS and DCIS-MI type 1 (respectively, 1.4% and none), in 10.1% with DCIS-MI type 2 and in 27.6% with IDC-DCIS. Metastasis free and overall survival probabilities were significantly different between three groups in the following order from best to worst prognosis: 1) the group comprising DCIS and DCIS-MI type 1, 2) the DCIS-MI type 2 group, and 3) the IDC-DCIS group. CONCLUSIONS: The authors' results suggest there are two types of DCIS-MI: 1) type 1 that behaves like DCIS and should be managed as such; 2) type 2 that is less pejorative than IDC-DCIS but is more so than type 1.

Adult↗

Interobserver variability: comparison between liquid-based and conventional preparations in gynecologic cytology.

BACKGROUND: Studies have shown that the ThinPrep Papanicolaou test (TP) increases the detection of epithelial cell abnormalities compared with the conventional preparation. Little is known about the interobserver variability of reporting gynecologic cytology results using the TP preparation and its comparison with results obtained using the conventional method. METHODS: To compare the interobserver variability between the TP method and the conventional method for reporting the diagnoses of gynecologic cytology, 20 pairs of conventional and TP slides (total, 40 slides) that were prepared from split samples were evaluated blindly by 19 cytotechnologists from three different laboratories. Each reviewer was asked to categorize each slide into the following five categories: within normal limits, benign cellular changes, atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesion (LSIL), and high-grade squamous intraepithelial lesion (HSIL). For both conventional and TP preparations, interobserver variability was analyzed using Spearman rank correlation coefficients. The mean correlation coefficients (weak, 0.0-0.4; fair, 0.4-0.7; and strong, 0.7-1.0) between the TP method and the conventional method were then compared. RESULTS: The overall interobserver agreement as well as interobserver agreement within each laboratory was good for both TP and conventional preparations. Based on the set of conventional cervical smears, only one slide that was diagnosed as HSIL had unanimous agreement; whereas, based on the set of TP slides, three slides, including two diagnosed as HSIL and one diagnosed as LSIL, had a unanimous diagnosis. The difference in the interobserver agreement between TP and conventional methods, based on comparing their mean +/- standard deviation correlation coefficients (TP method, 0.84 +/- 0.081; conventional method, 0.82 +/- 0.105; P < 0.001), was statistically significant. CONCLUSIONS: Interobserver agreement in reporting gynecologic cytology using the TP method is good, particularly for squamous intraepithelial lesions, and appears to be superior to the conventional method.

Carcinoma, Squamous Cell↗

ThinPrep-processed fine-needle samples of breast are effective material for RNA- and DNA-based molecular diagnosis: application to p53 mutation analysis.

BACKGROUND: Fine-needle sampling is the least invasive method of in vivo breast carcinoma sampling and can provide material for breast carcinoma diagnosis. The aim of the current study was to assess the accuracy of molecular diagnosis techniques using fine-needle sample (FNS) material stored in PreservCyt (Cytyc Corp., Boxborough, MA). METHODS: The p53 tumor suppressor gene was chosen as a model because it can be used for DNA, RNA, and protein analysis. Molecular analysis was performed using a yeast functional assay and DNA sequencing. p53 accumulation was evaluated by immunocytochemistry. RESULTS: DNA and protein analysis indicated that samples stored for periods of several months, either at room temperature, 4 degrees C, or -20 degrees C, can be processed reliably. For RNA-based diagnosis, samples were still intact after 5 months of storage in PreservCyt at 4 degrees C. In addition, using FNS material that was stored for 16 months at 4 degrees C, the authors detected p53 mutations with either the functional assay for separating alleles in yeast (an RNA-based functional assay) or direct cDNA sequencing. CONCLUSIONS: Fine-needle samples stored in PreservCyt at 4 degrees C are very good material for molecular diagnosis techniques. In addition, it is feasible to adopt a strategy of storing excess FNS material to create cellular banks that will be invaluable for future gene studies.

Biopsy, Needle↗

Comparison of ThinPrep and conventional smears in detecting carcinoma in bile duct brushings.

BACKGROUND: Bile duct brushing cytology is a common procedure for the exclusion of adenocarcinoma in the bile duct. The authors evaluated the use of ThinPrep (TP) to determine whether the information obtained is equivalent to that found with conventional smear cytology (CS). METHODS: Thirty-eight prospectively collected endoscope retrograde cholangiopancreatography-guided bile duct brushing samples were split in the following manner. First, two to four CS were prepared and immediately spray-fixed or wet-fixed. Second, the remaining sample was rinsed in PreservCyt (Cytyc Corp., Boxborough, MA). In the laboratory, one TP slide was prepared from each sample. TP and CS were stained by routine Papanicolaou stain. For the current study, TP and CS were reviewed independently by two cytopathologists. The diagnoses made by the two methods were compared with the final histology. RESULTS: The cytologic diagnoses for both TP and CS were categorized into five main groups: 1) unsatisfactory, 2) negative, 3) reactive, 4) suspicious for malignancy, and 5) malignant. The diagnoses on the 38 TP bile duct brushings and CS were categorized as follows: 1) unsatisfactory-2, 4; 2) negative-7, 4; 3) reactive-10, 14; 4) suspicious for malignancy-9, 9; and 5) malignant-10, 7, respectively. Histologic follow-up was available in 14 cases (reactive-4, suspicious for malignancy-1, and malignant-9). The sensitivity was 77% for TP and 66% for CS. The specificity was 100% for both methods. CONCLUSIONS: The two methods described in the current study detected equivalent disease on bile duct brushings. TP was found to provide better preservation and cytologic detail. However, the diagnostic criteria may require modification.

Adenocarcinoma↗

Liquid-based cytology and conventional cervical smears: a comparison study in an Asian screening population.

BACKGROUND: This study compared the findings of cervical cytology screening by ThinPrep Papanicolaou (Pap) tests (TP) with the findings of screening by conventional cervical smears (CS) in a screening population involving what to the authors' knowledge is the largest sample of ThinPrep Pap tests published to date. METHOD: Data from 191,581 CS that were screened in the period from March 1, 1998 to February 28, 2000 were compared with data from 190,667 TP performed from March 1, 2000 to February 28, 2002 and that were obtained from the same sources. RESULTS: With TP, the unsatisfactory rate was reduced from 0.48% to 0.32%. Fewer cases were considered to be suboptimal (19.12% vs. 12.97%). The detection rates of squamous cell carcinomas, adenocarcinomas, and high-grade squamous intraepithelial lesions (HSIL) were essentially unchanged in the TP group (0.005%, 0.003%, and 0.25%, respectively) compared with the rates for the CS group (0.01%, 0.006%, and 0.25%, respectively). There was an increase in the detection of atypical squamous cells of undetermined significance (ASCUS; 3.74% vs. 3.19%) and low-grade SIL (LSIL; 1.67% vs. 1.01%) with a decrease in the ASCUS-to-LSIL ratio from 3.15 for CS to 2.33 for TP. The detection of atypical glandular cells of undetermined significance (AGUS) increased slightly from 0.07% to 0.09%. The proportion of cells reported to have reactive atypia dropped from 2.71% to 1.48%. Limited biopsy correlation (range, 73.2-76.2%) confirmed the increased sensitivity of TP. More actinomyces (1.07% vs. 0.52%) were detected in TP samples despite of a similar portion of intrauterine-device users. The average primary screening and rapid rescreening time of each slide were reduced from 8 minutes to 4 minutes and from 2 minutes to less than 1 minute, respectively. CONCLUSIONS: The preliminary experience of the authors of the current study appears to support the use of the ThinPrep Pap test to enhance the efficiency of cervical cytology screening.

Adenocarcinoma↗

ThinPrep versus conventional Papanicolaou smear in the cytologic follow-up of women with equivocal cervical smears.

BACKGROUND: The purpose of the current study was to compare the efficacy of liquid-based cytology and conventional smears in the cytologic follow-up of cases with "atypical squamous cells, cannot exclude a high-grade lesion" (ASC-H) or "atypical glandular cells" (AGC). METHODS: Cytologic follow-up was performed on 214 cases with ASC-H/AGC diagnosis an conventional smears using either ThinPrep (n = 100) or conventional Papanicoloau (Pap) tests (n = 114). Results were then compared with further histologic and/or cytologic follow-up. RESULTS: Repetition on conventional smears enabled a definite diagnosis (within normal limits [WNL], squamous intraepithelial lesion [SIL] or carcinoma) in 58 cases (50.9%). ASC/AGC was confirmed in 50 cases (43.9%), and 6 of the smears (5.3%) were inadequate. WNL, SIL, or carcinoma was diagnosed in 82 (82.0%) cases by following the patients with ThinPrep cytology, whereas ASC or AGC was confirmed in 18 cases (18.0%). No inadequate specimens were found. A diagnosis of SIL or greater (SIL +) was confirmed histologically in 11 of 11 (100.0%) conventional smears and in 31 of 34 (91.2%) ThinPrep specimens. Of the 87 WNL specimens, 9 (8 conventional smears and 1 ThinPrep specimen) developed a histologically confirmed SIL during further follow-up. Specimen adequacy was significantly better in the ThinPrep specimens compared with conventional smears. CONCLUSIONS: Because of better specimen adequacy, ThinPrep cervical cytology appears to significantly reduce the occurrence of ASC/AGC compared with conventional Pap smears.

Adult↗

Results of the implementation of liquid-based cytology-SurePath in the Ontario screening program.

BACKGROUND: The objective of the current study was to evaluate the adequacy and detection rates of SurePath after its implementation in Ontario. METHODS: The detection and adequacy rates of the SurePath liquid-based cytology system (SP-LBC) were calculated for manually reviewed slides of the year 2002. The adequacy and detection rates from this study group were compared with a historical conventional smear (CS) group from the same laboratories during the same period of the previous year. RESULTS: The SP-LBC study group consisted of 352,680 specimens with cytodiagnoses and the CS group included 378,990 specimens. The unsatisfactory rate for SP-LBC (0.24%) was less than that of the CS group (0.58%). The detection rate of atypical squamous cells (ASC+) by the SP-LBC group (4.69%) was greater than that of the CS group (3.81%), as was the detection rate of low-grade squamous intraepithelial lesions (LSIL+; 2.13% vs. 1.50% in the CS group). There was only a trend toward increased detection of high-grade squamous intraepithelial lesions (HSIL+) in the SP-LBC group (0.34%) relative to the CS group (0.31%), because the detection rate for carcinoma by SP-LBC declined. CONCLUSIONS: The implementation of SP-LBC has been followed by better specimen adequacy and detection rates for ASC+, LSIL+, and a trend of increased detection of HSIL+ relative to CS practice. To determine sensitivity rates, a histopathologic database for cervical carcinoma and precancer needs to be established.

Carcinoma, Squamous Cell↗

Distribution of human papillomavirus types in ThinPrep Papanicolaou tests classified according to the Bethesda 2001 terminology and correlations with patient age and biopsy outcomes.

BACKGROUND: A survey of the distribution of human papillomavirus (HPV) types across the spectrum of cervical cytologic categories defined by the Bethesda 2001 guidelines was conducted with the objective of examining how HPV detection by polymerase chain reaction (PCR) analysis may benefit the management of patients who have abnormal Papanicolaou (Pap) test results. METHODS: DNA samples from women with no intraepithelial lesion or malignancy (NLM) (n = 300 samples); atypical squamous cells of undetermined significance (ASC-US) (n = 200 samples); low-grade squamous intraepithelial lesion (LSIL) (n = 200 samples); atypical squamous cells, cannot rule out high-grade squamous intraepithelial lesion (ASC-H) (n = 200 samples); and high-grade squamous intraepithelial lesion (HSIL) (n = 200 samples) were tested for HPV using a modified general primer (GP)5+/GP6+ PCR assay and dot-blot hybridization with type-specific oligonucleotide probes (PCR assay analytical sensitivity: 1-100 copies of HPV, depending on the HPV type, in a background of 100 ng human DNA). RESULTS: HPV was detected in 27% of NLM samples, in 89.5% of ASC-US samples, in 97.5% of LSIL samples, in 93% of ASC-H samples, and in 96.5% of HSIL samples. Thirty-seven different HPV types were identified in total. One or more of 13 high-risk (HR) HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) were detected in 53% of samples that were diagnosed as ASC-US (59.0% of patients younger than age 30 yrs; 45.5% of patients age 30 yrs and older), in 55.5% of samples that were diagnosed as LSIL (60.0% of patients younger than age 30 yrs; 44.0% of patients age 30 yrs and older), in 80% of samples that were diagnosed as ASC-H, and in 87.5% of samples that were diagnosed as HSIL (P < 0.001). HPV-16 was detected in 17.5% of ASC-US samples, in 15.5% of LSIL samples, in 48.5% of ASC-H samples, and in 49.0% of HSIL samples (P < 0.001). Among abnormal smears, HR HPV was significantly more common in women younger than age 30 years compared with women age 30 years and older (P < 0.002). Follow-up biopsy data were obtained for 359 patients. A "benign" biopsy result was recorded for 47 of 64 women (73.5%) with ASC-US, 30 of 66 women (45.5%) with LSIL, 39 of 87 women (45.0%) with ASC-H, and 26 of 142 women (18.0%) with HSIL and was most common in women age 30 years and older (P < 0.0001). Cervical intraepithelial neoplasia (CIN) Grade I (CIN-I) was found in 14.0% of women with ASC-US, in 39.5% of women with LSIL, in 8.0% of women with ASC-H, and in 7.0% of women with HSIL. CIN-II was diagnosed in 9.5% of women with ASC-US, in 13.5% of women with LSIL, in 19.5% of women with ASC-H, and in 24.0% of women with HSIL. CIN-III was identified in 2 women (3.0%) with ASC-US, in 1 woman (1.5%) with LSIL, in 24 women (27.5%) with ASC-H, and in 71 women (50.0%) with HSIL. CONCLUSIONS: HR HPV testing by PCR of samples diagnosed according to the Bethesda 2001 guidelines may benefit the management of patients with ASC-US or patients with LSIL, especially among women age 30 years and older, by allowing exclusion from referral for biopsy of women who are negative for HR HPV types. However, the small numbers of women who had CIN-III detected after a diagnosis of ASC-US or LSIL limited the assessment of test sensitivity.

Adult↗

On counting and counting errors.

Counting objects in histological sections is often a necessary, sometimes an unexpected part of a research project. The recent literature shows that the subject of counting is of particular interest to readers of the Journal of Comparative Neurology but that it is also contentious and difficult. Even a brief review of past issues of the Journal shows that there are many misconceptions about counting and that there remain issues that have received little or no attention. Counts are subject to many errors. Some reports include readily recognizable errors, others fail to include all of the information that is needed for an evaluation of their accuracy. This review is above all a plea for adequate information about the methods used for counts in all publications. It serves to help those who are new to quantitative methods in histology; it considers some of the basic issues arising for anyone undertaking counts, or reviewing manuscripts that include counts. In particular, it considers recently introduced or re-introduced counting methods that depend on accurate measures along the axis perpendicular to the plane of the sections, and looks at the difficulties inherent in these measures.

Animals↗

Timing of neuronal and glial ultrastructure disruption during brain slice preparation and recovery in vitro.

Hippocampal slices often have more synapses than perfusion-fixed hippocampus, but the cause of this synaptogenesis is unclear. Ultrastructural evidence for synaptogenic triggers during slice preparation was investigated in 21-day-old rats. Slices chopped under warm or chilled conditions and fixed after 0, 5, 25, 60, or 180 minutes of incubation in an interface chamber were compared with hippocampi fixed by perfusion or by immersion of the whole hippocampus. There was no significant synaptogenesis in these slices compared with perfusion-fixed hippocampus, but there were other structural changes during slice preparation and recovery in vitro. Whole hippocampus and slices prepared under warm conditions exhibited an increase in axonal coated vesicles, suggesting widespread neurotransmitter release. Glycogen granules were depleted from astrocytes and neurons in 0-min slices, began to reappear by 1 hour, and had fully recovered by 3 hours. Dendritic microtubules were initially disassembled in slices, but reassembled into normal axial arrays after 5 minutes. Microtubules were short at 5 minutes (12.3 +/- 1.1 microm) but had recovered normal lengths by 3 hours (84.6 +/- 20.0 microm) compared with perfusion-fixed hippocampus (91 +/- 22 microm). Microtubules appeared transiently in 15 +/- 3% and 9 +/- 4% of dendritic spines 5 and 25 minutes after incubation, respectively. Spine microtubules were absent from perfusion-fixed hippocampus and 3-hour slices. Ice-cold dissection and vibratomy in media that blocked activity initially produced less glycogen loss, coated vesicles, and microtubule disassembly. Submersing these slices in normal oxygenated media at 34 degrees C led to glycogen depletion, as well as increased coated vesicles and microtubule disassembly within 1 minute.

Animals↗