In an analysis of intermediate filament protein expression of spindle cell carcinoma, a variant of squamous cell carcinoma, occurring in larynx and tongue, vimentin positivity was found in sarcomatoid areas in 12 of 13 patients. Scattered expression of keratin was observed in sarcomatoid areas in tumours of 10 patients. However, large parts of sarcomatoid areas of such tumours were negative for keratin. Overlying dysplastic epithelium and squamous cell carcinoma components were positive for keratin. In a number of cases there was a strong indication of co-expression of keratin and vimentin in parts of cells that, on histological grounds, belong to sarcomatoid areas or to cells in the interface between carcinoma and spindle cell area. The use of keratin and vimentin type intermediate filament antibodies could be of great help for the correct classification of these tumours.

BioPEPR is a cathode ray tube scanning device that has been developed for the prescreening of cervical smears. Cervical samples are collected in suspension, syringed, counted and spread across a microscope slide. Feulgen-Thionine with Congo Red is used as the staining procedure. Fields of 6 x 8 mm are scanned at 1 p resolution, using an intermediate photographic step. Morphologic parameters of the cells are measured, as called for by a hierarchical decision strategy. Analysis speed is currently about 4 min per smear; improvements of at least a factor of four are expected. A field test of BioPEPR is being undertaken in cooperation with a local population screening program. In the study two smears are made from each woman; the first is prepared according to _ _ _ _~~ ~~~ the Papanicolaou technique while the second is prepared and stained according to the BioPEPR methods. In addition to smears from the population screening program a number of possibly abnormal smears are obtained from several gynecological clinics. To date approximately 3500 "second" smears have been analyzed by the BioPEPR system. The results show a missed positive rate on the order of a few percent (no missed positives were more severe than a slight dysplasia), and a false alarm rate of about 24%. A further analysis of the age distribution of the false alarm rate shows that a large proportion came from women above the age of 50; the false alarm rate is about 20% for women under the age of 50.

A feasibility study has indicated that a Precision Encoding and Pattern Recognition (PEPR) cathode ray tube prescreening system for cervical smears can be both accurate and fast. Smears are prepared using a syringing technique and are stained with a Feulgen-type nuclear stain and a protein counter

No abstract

Thirty-six ovarian and renal-cell tumours were analyzed by flow cytometry (FCM) for DNA content and in parallel were assayed for colony formation in a human tumour cloning system (HTCS). While 15/19 (79%) tumours with an abnormal (aneuploid) DNA stemline formed colonies in the HTCS, only 2/17 (12%) of diploid tumours formed colonies. All samples contained tumour cells as assessed by routine cytological examination. The capacity to form colonies in the HTCS was not correlated in these tumours with grade or stage of disease or tumour type. The level of aneuploidy expressed as the FCM DNA index did not correlate with the cloning efficiency in HTCS. These findings suggest that tumour growth in the HTCS reflects a biologically important potential, related in at least some tumours to an abnormal DNA stemline.