Proliferation accurately identifies the high-risk patients among small, low-grade, lymph node-negative invasive breast cancers.

BACKGROUND: The proliferation factor mitotic activity index (MAI) is the strongest prognosticator in lymph node-negative invasive breast cancer patients under age 71. The question remains, whether this also holds for 'favourable prognosis' subgroups. PATIENTS AND METHODS: The study was a multicentre prospective analysis of the MAI for recurrence-free survival and overall cancer-related survival of grade, MAI, and other prognosticators in 853 long-term follow-up, T1-3N0M0 breast cancer patients under 71 years. RESULTS: In all tumours together (N = 853), in grade 3 (n = 269), in tumours <1 cm all grades (n = 84), 1-2 cm, grades 1 + 2 (n = 300), and 2-3 cm, grades 1 + 2 (n = 124), the MAI is prognostically superior. Other features [grade, estrogen receptor (ER), diameter, and age] did not enhance its prognostic value except in grades 1 + 2 tumours 2-3 cm diameter with MAI <10, where ER has an additional prognostic value. CONCLUSIONS: In women <71 years with T1-3N0M0 small or low-grade invasive breast cancer usually not receiving systemic treatment, MAI > or =10 accurately identifies those at high risk. These high-risk patients should be considered for adjuvant systemic therapy.

Dynamic behavioural interpretation of cervical intraepithelial neoplasia with molecular biomarkers.

The microscopic phenotype of cervical intraepithelial neoplasia (CIN) reflects a fine balance between factors that promote or reduce CIN development. A shortcoming of the current grading system is its reliance on static morphology and microscopic haematoxylin-eosin features of the epithelium alone. In reality, CIN is a dynamic process, and the epithelium may exhibit differing results over time. Functional biomarkers p16, Ki-67, p53, retinoblastoma protein cytokeratin (CK)14 and CK13, help in the assessment of an individual CIN's lesion's potential for progression and regression. The aggregate information provided by these biomarkers exceeds the value of the classic grading system. Consequently, many more CINs that will either regress or progress can be accurately identified. These findings agree with known molecular interactions between HPV and the host. For accurate interpretation of a CIN, it is essential that these biomarkers be determined quantitatively and separately in the superficial, middle and deep layers of the epithelium. Such geography-specific epithelial evaluations of quantitative biomarkers emphasise the dynamic nature of a particular CIN lesion, thereby changing the art of static morphology grading into dynamic interpretation of the diseased tissue, with a strong prognostic effect.

Quantitative determination of factors contributing to doxorubicin resistance in multidrug-resistant cells.

There is a large discrepancy between the changes in drug accumulation and the changes in drug cytotoxicity that accompany development of anthracycline resistance in multidrug-resistant cells. In our study, a quantitative relationship has been established between reversal of multidrug resistance by resistance modifiers and a concomitant decrease in intracellular levels of doxorubicin measured at equitoxic concentrations (IC50) in CHRC5 and 2780AD multidrug-resistant cells. (IC50 = concentration required for 50% growth inhibition.) We have demonstrated that resistance modifiers like verapamil and Ro 11-2933/001 act by increasing the effectiveness of intracellular doxorubicin, apparently by inducing redistribution of the drug from the cytoplasm to the nucleus of a multidrug-resistant cell, as shown by quantitative fluorescence microscopy. At complete reversal of resistance, as measured directly or inferred by extrapolation, the amount of intracellular doxorubicin at the IC50 as well as the ratio of nuclear doxorubicin to cytoplasmic doxorubicin were the same as those in sensitive cells. These results offer an explanation for the frequently observed discrepancies between drug accumulation and cytotoxicity and also show quantitatively that a decrease in drug accumulation and a change in intracellular drug distribution together are the only determinants of doxorubicin resistance in the multidrug-resistant cells studied.

Altered PTEN expression as a diagnostic marker for the earliest endometrial precancers.

BACKGROUND: PTEN tumor suppressor gene mutations are the most frequent genetic lesions in endometrial adenocarcinomas of the endometrioid subtype. Testing the hypothesis that altered PTEN function precedes the appearance of endometrial adenocarcinoma has been difficult, however, partly because of uncertainties in precancer diagnosis. METHODS: Two series of endometrial cancer and precancer (endometrial intraepithelial neoplasia, as diagnosed by computerized morphometric analysis) tissue samples were studied, one for PTEN mutations by the use of denaturing gradient gel electrophoresis and another for PTEN protein expression by immunohistochemistry. Endometria altered by high estrogen levels that are unopposed by progestins-conditions known to increase cancer risk-were also studied by immunohistochemistry. Fisher's exact test was used for statistical analysis. RESULTS: The PTEN mutation rate was 83% (25 of 30) in endometrioid endometrial adenocarcinomas and 55% (16 of 29) in precancers, and the difference in number of mutations was statistically significant (two-sided P =.025). No normal endometria showed PTEN mutations. Although most precancers and cancers had a mutation in only one PTEN allele, endometrioid endometrial adenocarcinomas showed complete loss of PTEN protein expression in 61% (20 of 33) of cases, and 97% (32 of 33) showed at least some diminution in expression. Cancers and most precancers exhibited contiguous groups of PTEN-negative glands, while endometria altered by unopposed estrogens showed isolated PTEN-negative glands. CONCLUSIONS: Loss of PTEN function by mutational or other mechanisms is an early event in endometrial tumorigenesis that may occur in response to known endocrine risk factors and offers an informative immunohistochemical biomarker for premalignant disease. Individual PTEN-negative glands in estrogen-exposed endometria are the earliest recognizable stage of endometrial carcinogenesis. Proliferation into dense clusters that form discrete premalignant lesions follows.

Molecular identification of latent precancers in histologically normal endometrium.

Discovery of somatically mutated cells in human tissues has been less frequent than would be predicted by in vitro mutational rates. We analyzed the PTEN tumor suppressor gene as an early marker for endometrial carcinogenesis, and we show that 43% of histologically normal premenopausal endometria contain rare glands that fail to express PTEN protein because of mutation and/or deletion. These persist between menstrual cycles. Histopathology of PTEN-null glands is initially unremarkable, but with progression, they form distinctive high-density clusters. These data are consistent with a progression model in which initial mutation is not rate limiting.

Kinetics and tissue distribution of the radiolabeled chimeric monoclonal antibody MOv18 IgG and F(ab')2 fragments in ovarian carcinoma patients.

Twenty-four patients suspected of having ovarian carcinoma received i.v. injection with a combination of radiolabeled intact IgG (1 mg) and F(ab')2 fragments (1 mg) of the chimeric monoclonal antibody MOv18, each form labeled with 1.85 MBq 131I or 125I. Laparotomy was performed either 2 or 6 days after injection, and the uptake of radioactivity was determined in a total of 329 biopsies of normal and malignant tissues. The mean elimination half life in plasma of cMOv18 IgG and F(ab')2 was 70 +/- 8 (SD) and 20 +/- 5 h, respectively. The mean uptake of IgG in tumor biopsies was 3.6-fold higher two days after injection and 6.9-fold higher than the uptake of F(ab')2 6 days after injection. Uptake in normal tissues was 3.3 and 5.5 times higher for IgG at 2 and 6 days, respectively. Two days after injection, the mean ratio of the uptake in tumor:normal tissue/patient was 3.8 +/- 1.5 and 4.0 +/- 1.8 for radiolabeled cMOv18 IgG and F(ab')2, respectively. Six days after injection, this was 6.7 +/- 4.7 for Ig G and 5.7 +/- 4.1 for F(ab')2. cMOv18 IgG has a longer circulation time in blood, a higher uptake in tumor and normal tissues, and a longer retention time compared to the F(ab')2 fragments. However, the tumor:normal tissue ratios are similar. The results do not warrant a definite conclusion as to which antibody form is most suitable for therapeutic application of antibodies but provide a more firm basis for rational design of therapeutic targeting studies using immunoconjugates.

Functional multidrug resistance phenotype associated with combined overexpression of Pgp/MDR1 and MRP together with 1-beta-D-arabinofuranosylcytosine sensitivity may predict clinical response in acute myeloid leukemia.

Overexpression of P-glycoprotein (Pgp) or MDR1 mRNA has been shown to be a negative prognostic factor for clinical outcome in acute myeloid leukemia (AML). However, resistance to chemotherapy also occurs in the absence of Pgp overexpression. Therefore, besides Pgp expression, we have assessed the expression of MRP, a novel drug transporter gene, along with the functional multidrug-resistant (MDR) phenotype of leukemic cells. These MDR parameters are correlated with clinical outcome in individual patients. We found functional changes in fresh leukemic cells from de novo or relapsed patients similar to those reported for tumor cell lines with the MDR phenotype. These changes were reduced drug accumulation as assessed with radiolabeled doxorubicin (factor 1.6), daunomycin (factor 1.13), and vincristine (factor 1.6) in patients who were refractory to the combination treatment of 1-beta-D-arabinofuranosylcytosine (ara-C) and daunomycin or mitoxantrone as opposed to patients who had complete responses. Also, the intracellular distribution of doxorubicin fluorescence (nuclear/cytoplasmic ratio), as assessed with laser scan microscopy, was reduced 1.4-fold in blasts from refractory patients. Based on historically known clinical response to single-agent daunomycin or ara-C in the group of responding de novo AML patients, we have set a threshold level such that a defined part of the samples that had the highest drug accumulation or nuclear to cytoplasmic ratios were above this threshold value. This allowed discrimination between patients responding to daunomycin from those who were refractory to this drug. By using this threshold level, in the refractory group clinical resistance corresponded with high sensitivity with a resistant phenotype. A similar threshold was set for the data of the in vitro ara-C sensitivity test. By combining both assays for all individual patients, clinical refractoriness as well as sensitivity could be predicted with high accuracy. There appeared to be no stringent relationship between the functional MDR phenotype with expression of either Pgp (fluorescence-activated cell sorting analysis) or MRP mRNA (RNase protection). However, by combining both parameters the functional MDR phenotype correlated with the overexpression of either one or both of the parameters in 94% of the samples studied. It is concluded that this combined overexpression in conjunction with functional changes for MDR drugs and ara-C reveal a correlation of MDR phenotype with clinical resistance to combination chemotherapy in AML patients and hereby may adequately predict clinical MDR in individual AML patients.

Borderline malignancy of the ovary and controlled hyperstimulation, a report of 2 cases.

We report 2 patients who developed a borderline malignancy of the ovary after treatment with follicular stimulants in the context of an in vitro fertilisation (IVF) programme. In both cases, conservative surgery for the borderline malignancy was sufficient treatment. Ultimately, both patients became pregnant, 1 after IVF treatment and 1 without treatment, and both delivered healthy babies. In addition to the presentation of both cases, the literature concerning the possible risks of treating patients with high dosage, exogenously administered hormones is reviewed and the possible association between exogenous hormones and the risk of developing ovarian cancer is discussed.

Genomics and proteomics in cancer.

Cancer development is driven by the accumulation of DNA changes in the approximately 40000 chromosomal genes. In solid tumours, chromosomal numerical/structural aberrations are common. DNA repair defects may lead to genome-wide genetic instability, which can drive further cancer progression. The genes code the actual players in the cellular processes, the 100000-10 million proteins, which in (pre)malignant cells can also be altered in a variety of ways. Over the past decade, our knowledge of the human genome and Genomics (the study of the human genome) in (pre)malignancies has increased enormously and Proteomics (the analysis of the protein complement of the genome) has taken off as well. Both will play an increasingly important role. In this article, a short description of the essential molecular biological cell processes is given. Important genomic and proteomic research methods are described and illustrated. Applications are still limited, but the evidence so far is exciting. Will genomics replace classical diagnostic or prognostic procedures? In breast cancers, the gene expression array is stronger than classical criteria, but in endometrial hyperplasia, quantitative morphological features are more cost-effective than genetic testing. It is still too early to make strong statements, the more so because it is expected that genomics and proteomics will expand rapidly. However, it is likely that they will take a central place in the understanding, diagnosis, monitoring and treatment of (pre)cancers of many different sites.

Prospective multicenter evaluation of the morphometric D-score for prediction of the outcome of endometrial hyperplasias.

Prospective multicenter evaluation of the WHO classification and the morphometric D-score to predict endometrial hyperplasia cancer progression. In 132 endometrial hyperplasias WHO classification was performed by two experienced gynecologic pathologists. The D-score was assessed blindly by technicians in a routine diagnostic setting. Development of endometrial carcinoma during a 1-10-year follow-up was used as the end point. Eleven of 132 patients (8%), 10 of 61 (16%) atypical hyperplasias, and 1 of 71 (1%) nonatypical hyperplasias developed cancer. Twenty-six curettings had a D-score < or = 0 ("unfavorable" or endometrial intraepithelial neoplasia) of which 10 (38%) developed cancer. None of the 86 cases with a D-score > 1 ("favorable") and one of the 20 (5%) cases with 0 < D-score < or = 1 ("uncertain") developed cancer. Sensitivity of the D-score was 100%, specificity 82%, the positive and negative predictive values were 38% and 100%, respectively. These values are similar to those in three prior retrospective D-score studies but higher than the WHO values (which are 91%, 58%, 16%, and 99%, respectively). The D-score in endometrial hyperplasias is a more sensitive and specific marker for cancer prediction than the WHO classification, can be assessed in a routine clinical setting on standard hematoxylin and eosin sections (15-30 minutes per case), and is highly reproducible and cost-effective (U.S. $50 per case).

The antiproliferative effect of 8-chloro-adenosine, an active metabolite of 8-chloro-cyclic adenosine monophosphate, and disturbances in nucleic acid synthesis and cell cycle kinetics.

8-Chloro-adenosine, the dephosphorylated metabolite of the antineoplastic agent 8-chloro-cyclic AMP, has been proposed to act on the regulatory subunits of cyclic AMP-dependent protein kinase. 8-Chloro-adenosine has a growth-inhibitory effect, the mechanism of which is unclear. We investigated the effects of 8-chloro-cyclic AMP and 8-chloro-adenosine on nucleic acid synthesis and cell cycle kinetics in two human glioma cell lines. These effects were compared to those of the cyclic AMP analogue 8-(4-chlorophenyl)-thio-cyclic AMP (8-CPTcAMP), which is less susceptible to dephosphorylation. Whereas 8-CPTcAMP almost completely inhibited RNA and DNA synthesis, both 8-chloro-adenosine and 8-chloro-cyclic AMP only partly inhibited synthesis of RNA and DNA at growth-inhibitory concentrations, as demonstrated by using [5-1H] uridine and [14C]thymidine incorporation. Therefore, the growth-inhibitory effect of 8-chloro-cyclic AMP is not (or not completely) due to activation of cyclic AMP-dependent protein kinase nor to the inhibition of nucleic acid synthesis. Flow cytometric analysis revealed that 8-chloro-cyclic AMP and 8-chloro-adenosine probably block cell cycle progression at the G2M phase. The effects of 8-chloro-cyclic AMP on nucleic acid synthesis and cell cycle progression were largely prevented by adenosine deaminase, which inactivates 8-chloro-adenosine. This indicates that the effects of 8-chloro-cyclic AMP were at least in part due to its metabolite 8-chloro-adenosine. Incorporation of 8-chloro-adenosine into RNA and DNA might contribute to the disturbance of the cell cycle kinetics and growth-inhibitory effect of 8-chloro-adenosine.

Placenta morphology and absent or reversed end diastolic flow velocities in the umbilical artery: a clinical and morphometrical study.

The aim of the study was to investigate if a relation exists between absent or reversed end diastolic (ARED) flow in the umbilical artery and morphometric characteristics of the placenta. Geometric parameters were measured in the terminal villi of nine placentae, collected after a pregnancy complicated by ARED flow. Placentae from pregnancies with normal Doppler velocimetry in the umbilical artery were matched for gestational age and formed the control group. Mean placental weight in the ARED group was significantly lower than in the control group. Morphometric characteristics of the terminal placental villi did not differ substantially between the two groups before 30 weeks gestation. After 30 weeks mean villous profile cross sectional area and diameter were significantly smaller in the ARED group than in the control group. The mean profile cross sectional villous diameter in the ARED group did not differ substantially before and after 30 weeks of gestation (2287 microns2 and 2303 microns2, respectively). Accelerated maturation of terminal villi occurs in placentae delivered after a pregnancy with ARED flow in the umbilical artery. Morphometric characteristics are significantly different between placentae expelled after ARED velocities or after normal Doppler recordings in the umbilical artery. In ARED placentae, a significantly more uniform pattern of small villi is found compared with control placentae.

Cytogenetic characteristics of oral squamous cell carcinomas in Fanconi anemia.

Fanconi anemia (FA) is an autosomal recessive syndrome with a marked predisposition to malignancies, in particular acute myeloid leukemia and squamous cell carcinoma of the oral cavity. We examined oral squamous cell carcinoma tissue from two FA patients (FA-A and FA-C) by comparative genomic hybridization. Both tumors, which were negative for human papilloma as well as Epstein-Barr viral sequences, showed multiple alterations with a high proportion of whole-arm chromosomal gains and losses. This combination of features as well as the sites involved in chromosomal breakage are very similar to what is typically observed in non-FA oral tumors. These results suggest that the process leading to early occurrence of oral cancer in FA patients follows a similar pathway as in non-FA cancer patients, which would support a caretaker function for FA genes in the protection against oral carcinogenesis. Since FA patients are uniquely hypersensitive to DNA cross-linking agents, while oral cancer in the general population is thought to be environmentally induced, these results also suggest that environmental DNA cross-linkers may be causally involved in oral carcinogenesis.

The morphometric prognostic index is the strongest prognosticator in premenopausal lymph node-negative and lymph node-positive breast cancer patients.

Earlier studies on breast cancer have shown the strong prognostic value of morphometric parameters (especially the morphometric prognostic index [MPI]) in comparison with clinical and classical pathologic parameters. It remained to be proven whether the prognostic value of the MPI holds for the subgroup of premenopausal patients. We have therefore investigated the value of different prognosticators in a group of 211 premenopausal breast cancer patients with long-term follow-up, 121 cases being lymph node-negative and 90 cases being lymph node-positive. The MPI, a multivariate combination of the mitotic activity index (MAI), lymph node status, and tumor size, was the best combined prognosticator (P less than .0001), exceeding the prognostic value of MAI, lymph node status, and tumor size as individual parameters and as indicators of histologic grade. Of all the features studied, the MPI had the best prognostic value in the lymph node-negative patients, while the MAI and MPI had the best prognostic value in the lymph node-positive patients. Since the MPI has been shown to be reproducible in intra- and interlaboratory studies and can be assessed with standard equipment in routine histologic sections, it is an attractive indicator for selecting high-risk lymph node-negative patients for systemic adjuvant therapy trials.

Reproducibility of mean nuclear volume and correlation with mean nuclear area in breast cancer: an investigation of various sampling schemes.

Previous studies have shown that quantitative, histopathologic features obtained from a carefully selected area in the tumor section ("selective" approach) have a strong prognostic value in breast cancer. On the other hand, it was found that mean nuclear volume estimation in the whole area of the tumor section by means of "unbiased" stereologic techniques is of great value in predicting the clinical outcome as well. In the present study the results of the two different (ie, selective and random, systematic) sampling methods in assessing mean nuclear volume have been compared as to their intraobserver and interobserver reproducibility in 22 invasive breast cancer cases. The mean nuclear volume (nuclear vv) was assessed both in the most atypical area (AREA) (selected on morphologic criteria) and in the whole tumor section (TOTAL). Furthermore, the correlation with mean nuclear (profile) area (MNA) was studied. Mean nuclear (profile) area was determined in the AREA only. With bivariate correlation analysis the two sampling methods showed high correlation for the nuclear vv values (range of the correlation coefficient, 0.92 to 0.97). There were no systematic intraobserver differences between the different sampling methods. The results of observer 1 showed higher values, both with the selective and random systematic sampling methods. However, these systematic interobserver differences were small (< 9% of the average value of nuclear vv), much smaller than the variation between the tumors (which was > 60%). The time required for assessments in the AREA was less than that required for the determinations in the TOTAL (average, 10 v 20 minutes) in spite of the similar sample size. This is understandable, as in a sclerotic tumor many fields of vision do not contain cancer nuclei. The time required for MNA determinations in the AREA was longer than for nuclear vv assessments in the AREA (15 v 10 minutes). Nuclear vv and MNA (both assessed in the AREA) were (log distributed) significantly correlated (r = .77). Thus, nuclear vv determination in the AREA is the fastest method, and it is also well reproducible and strongly correlated with nuclear vv assessed in the TOTAL. In invasive breast cancer assessments in the whole tumor section can be used if delineation of the measurement area cannot be done easily. In small areas with a limited number of nuclei (eg, microinvasive parts) MNA can be easier to assess than nuclear vv. Further studies are required to compare and evaluate the prognostic value of nuclear vv and MNA.

Analysis of measuring system parameters that influence reproducibility of morphometric assessments with a graphic tablet.

The morphometric analysis of nuclear characteristics by means of a graphic tablet is, in principle, objective and highly reproducible. However, a recent study found considerable variation in the morphometric assessments, which was in contrast to the findings of others. The way in which measurements were performed differed in these studies. Therefore, measuring system factors that can potentially influence the quantitative results were analyzed systematically. One observer, experienced in microscopic analysis and working with a commercially available graphic tablet, conducted all the measurements, thus excluding interobserver variation. The tracing speed, localization (on the graphic tablet), magnification, pen and cursor usage, shape, and orientation on the graphic tablet were analyzed. A nomogram was developed for cursor application that indicates the relation between "projected" particle size, tracing speed, and required coefficient of variation (CV). When the influence of these factors is taken into account, a measuring system can be tuned optimally. With such a regimen, the CV can be kept below 1.5%. Our results show that in the assessment of morphometric features with the use of a graphic tablet, errors due to the measuring system can be virtually eliminated.

Syntactic structure analysis in invasive breast cancer: analysis of reproducibility, biologic background, and prognostic value.

The reproducibility, biologic background, and prognostic value of syntactic structure analysis were studied in a group of 94 patients with invasive primary breast cancer. Using an interactive digitizing video overlay system, the centers of malignant breast cancer nuclei were marked in the five (subjectively) most cellular fields of vision for each case at a final magnification of X1,200, and the corresponding minimum spanning tree was composed for each field. From each minimum spanning tree, 10 syntactic structure features were derived; subsequently, the mean, standard deviation, minimum, and maximum values of the five fields analyzed were calculated for further statistical analysis. Forty statistics thus were available for each case. The reproducibility of repeatedly measuring the same field (independent of nuclearity) and the same patient twice by the same or different observers was good for most of the syntactic structure features. When comparing the statistics of the syntactic structure features with other established prognosticators, correlations were found with (in this order) standard deviation and mean nuclear area (expressing nuclear differentiation), volume percentage epithelium (expressing architectural differentiation), and mitotic activity index. In univariate survival analysis several syntactic structure statistics yielded prognostic significance, the best being the maximum of the number of nuclei with two neighbors (P = .002; Mantel-Cox test, 12.4). Multivariate analysis revealed that syntactic structure features did not provide additional prognostic values with regard to each other. However, they did show additional prognostic values with regard to the multivariate prognostic index (currently one of the best prognosticators in breast cancer), which combines the mitotic activity index, lymph node status, and tumor size. Measurement of syntactic structure features could therefore contribute to an improved prediction of prognosis of breast cancer patients. In conclusion, syntactic structure analysis is a simple, fast, and highly reproducible technique that shows prognostic value in invasive breast cancer and also has important prognostic value with regard to the well-established and prognostically strong morphometric features. It seems to be a promising new method of analyzing tissue architecture in breast cancer and perhaps in many other tumors.

Quality control methods for data entry in pathology using a computerized data management system based on an extended data dictionary.

In pathology, computerized data management systems have been used increasingly to facilitate a more efficient supply of information. Since data entry precedes data utilization, the reliability of the information stored strongly depends on the quality of data input. Despite its potential capability, most personal computer-based database software does not provide versatile and user-friendly data validation procedures. Therefore, we developed a data dictionary-driven data management system that enables the user to perform extensive validation routines without the need for hard programming. Using examples from an existing database for endometrial carcinomas, different types of data errors and their error traps are explained. It is pointed out that data type definitions, defaults, templates, or picture clauses are suitable means to avoid formal errors. Validations on data domains and ranges test whether data fall into a predefined scope. Relational checks control data validity within a context of different data items, whereas process routines provide automatic data computation, thereby circumventing user input. By exploiting the facilities of an extended data dictionary, a powerful tool is made available to secure various aspects of data integrity simultaneously with input. In this way, computerized data quality control can improve the efficiency and reliability of data management tasks in pathology.

Comparison of the prognostic value of four methods to assess mitotic activity in 186 invasive breast cancer patients: classical and random mitotic activity assessments with correction for volume percentage of epithelium.

Proliferation markers and especially the Mitotic Activity Index (MAI) are strong and reproducible prognosticators in invasive breast cancer. Traditionally, the MAI has been defined as the total number of mitoses counted in 10 consecutive high-power fields (objective, x40; numeric aperture, .75; field diameter, 450 microns), in the most cellular area at the periphery of the tumor, with the subjectively highest mitotic activity. No correction for epithelial percentage or cellularity was applied. This study investigates whether the prognostic value of mitotic activity could be improved by a random sampling procedure or correction for percentage of epithelium present. For this purpose the prognostic value of four methods used to assess mitotic activity in invasive breast cancer was compared in 4-microns-thick hematoxylin-eosin (H&E)-stained sections of 186 primary invasive breast cancer patients. These were the MAI, the random MAI (rMAI), the Mitosis per Volume (M/V) Index, and the random M/V Index (rM/V Index). The rMAI was defined as the total number of mitotic figures counted in 10 random fields through the whole outlined tumor at x400 magnification. A correction for the volume percentage of epithelium assessed with stereology yielded the M/V Index and the rM/V Index, respectively. The results of all four methods showed moderate to high correlations. Univariate survival analysis (Kaplan-Meier curves; Mantel-Cox test) confirmed that all four methods had a strong prognostic value (P < .001). The MAI, however, produced the best results (Mantel-Cox value, 17.1). Multivariate analysis showed that all four methods had additional prognostic value to tumor size and lymph node status. The M/V Index provided most additional prognostic information, followed by the MAI. Assessment of rMAI took 20 to 30 minutes on average, about two times longer than MAI. The correction for volume percentage of epithelium took about 10 minutes longer for both methods than the uncorrected methods. In conclusion, the rMAI gives an impression of the mitotic activity through the whole tumor, with almost similar prognostic value as the traditional MAI, especially when correcting for percentage of epithelium. Nevertheless, the MAI is still to be preferred, because the assessment is easy to apply and less time consuming.

Evaluation of a Diagnostic Encyclopedia Workstation for ovarian pathology.

The Diagnostic Encyclopedia Workstation (DEW) is a computer system that provides completely integrated pictorial and textual information as reference knowledge in the field of ovarian pathology. The textual component comprises information per diagnosis such as descriptions of macroscopic and microscopic images, clinical signs, and prognosis. In addition, the system offers lists of differential diagnoses and criteria to differentiate among lists of differential diagnoses and criteria to differentiate among them. The present study evaluates to what extent the system influences the diagnostic process in efficiency and outcome. Therefore, two groups of six pathologists each, covering a wide spectrum of experience in ovarian pathology, participated in the evaluation of the DEW. The quality of the resulting diagnoses was statistically analyzed with the Wilcoxon rank sum test with respect to five different viewpoints: classification, morphology, clinical consequences, duration of diagnostic process, and consensus among the participants. The results are discussed and it is concluded that classification and morphology showed better results when books were used. The evaluation experiment was, however, very rigid and negatively biased with respect to the DEW system. Positive aspects of the encyclopedia are the easy access to diagnostic and differential diagnostic information and the large set of illustrations. Insight is acquired with respect to existing bottlenecks and how they may be overcome.