The PAPNET method is an interactive computer-assisted screening procedure. The diagnostician selects the abnormal video tiles out of the 128 and decides which smears need additional light microscopy. The original diagnoses of 1494 archival smears were compared with the PAPNET analysis of the same smears. The general trend observed was that the PAPNET-assisted diagnoses were of a higher grade than those assigned by the primary screener, thus less cases were signed out as negative. In addition, the PAPNET method was used for primary screening of 2971 randomly selected smears, whilst in the same period 5797 smears were conventionally screened. Using the PAPNET method, significantly fewer smears were signed out as negative. Seventy-three percent of the cases were diagnosed on the basis of the information provided by the 128 video tiles, 11% had to be screened completely by the light microscope, and the remaining cases needed additional light microscopy of a part of the smear. As a result, PAPNET-assisted screening was approximately two times faster. The great advantage of the method is that it is much less tiring for the eyes than conventional screening, making fatigue-related errors less likely, and if a smear contains only a few abnormal cells, these are easier to find.

In this paper we describe a method of preparing tissue blocks for paraffin sections within 30 min. The method is based on microwave-stimulated diffusion reducing the dehydrating, clearing, and impregnating times by a factor of 48. The developed technique was inspired by the experimentally observed sizable temperature-dependence of viscosity and other transport properties of liquids. It is clear that, by considering the theoretical aspects of diffusion and by analysis of the influence of the used chemicals in different tissue depths, histotechnical results can be optimized. The histotechnical microwave results are light-microscopically excellent and indistinguishable from those of the well-performed 'classical' method. The nuclear size of several cell types hardly differs in both methods. The new method is valuable in particular for individual cases in which a fast diagnosis is asked for, and in which a frozen-section diagnosis is thought to be too unreliable. In addition, this method can be used in small research laboratories processing small quantities of histological material. The only equipment needed to prepare tissue blocks of optimal quality is the microwave oven.

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A heavy admixture of blood in cervical smears can be problematic for the screener, as the presence of blood can influence the staining quality of the cancer cell nuclei. However, it might also be a blessing in disguise. A retrospective study of 40 clinically important smears, 34 originally signed out as negative for squamous cell carcinoma of the cervix and 6 smears as unsatisfactory, was carried out in comparison with 100 smears from healthy women. Sample parameters were analyzed by macroscopy and neural network scanning. Differences between the two study groups were measured by Pearson's chi(2) test. Of the 40 study cases, one case featured insufficient material, while 16 cases (40%) could confidently be classified as malignant or negative for malignancy. The most important macroscopic parameter of the smears was an admixture of blood. This background feature was also highlighted by the NNS system. Angiogenesis was visualized by the expression of CD34 in many sampled capillary fragments included in the smears. In conclusion, blood in cervical smears may have clinical and diagnostic significance. The rate of "failed smears" in routine cervical screening might thus by CD34 be considerably decreased.