[en] The discovery of palpable lesions (adenopathy, subcutaneous, breast and thyroid nodes, etc.) in patients with malignancies of various locations referred for radiotherapy, poses diagnostic problems which should be promptly resolved since it may result in changes in the anticipated therapeutic regime. Likewise, the presentation of such lesions in previously irradiated patients raises the differential diagnosis between a progression of the disease and a non-malignant condition. Given the experience and the ease with which fine needle puncture and aspirations is carried out, previding-according to published data a diagnostic accuracy of 76% to 100% in palpable nodules, the usefulness of this procedure was assessed in 35 patients who presented with palpable lesions among a total of 428 new patients seen at the Radiotherapy Department of the Hospital Clinico Universitario, Valencia, in 1985. Out of the 35 lesions, 17 were adenopathies. In 63% of cases, the patients had head and neck malignancies; 14% had breast tumors; 11% had lung cancer and the remaining 11% of patients had malignancies located elsewhere. 43% were discovered before radiotherapy was administered, 14% during the treatment and 43% after this, in routine follow-up visits. Cytological diagnosis was achieved in 89% of cases. An overall clinical and pathological correlation was obtained in 58% of cases. Then out of 20 positive fine needle aspirations determined changes in the therapeutic regime (7 out of 15 prior to radiotherapy and 5 out of 5 during this). After radiotherapy, the clinical and pathological correlation is worse, in 33% of cases, than prior to or during this treatment. In four cases in which fine needle puncture and aspiration was negative but clinical suspicion of tumor involvement was high, open biopsy proved to be negative. (Author). 9 refs

[en] The purpose of this overview to show briefly: how mutation is thought to occur; how mutations and related events are currently detected; and where they may be targets of opportunity for cytometric automation leading to improved biologic dosimetry of mutagenesis in the human and other species. (orig./AJ)

[en] Accurate detection of the human metaphase chromosome centromere is an critical clement of cytogenetic diagnostic techniques, including chromosome enumeration, karyotyping and radiation biodosimetry. Existing methods can perform poorly in the presence of irregular boundaries, shape variations and premature sister chromatid separation, which can adversely affect centromere localization, ^VI' present a centromere detection algorithm that uses a novel profile thickness measurement technique on irregular chromosome structures defined by contour partitioning. Our algorithm generates a set of centromere candidates which arc then evaluated based on a set of features derived from images of chromosomes. Irregular chromosome structures arising from sample preparation can produce incorrect centromere locations. Our method also partitions the chromosome contour to isolate its telomere regions and then detects and corrects for sister chromatid separation. When tested with a chromosome database consisting of 1400 chromosomes collected from 40 metaphase cell images, the candidate based centromere detection algorithm was able to accurately localize 1220 centromere locations yielding a detection accuracy of 87%. We also introduce a Candidate Based Centromere Confidence (CBCC) metric which indicates an approximate confidence value of a given centromere detection find can be readily extended into other candidate related detection problems. (author)

[en] Objective: To evaluate the diagnostic accuracy, usefulness and limitations of ultrasound guided FNAC of hepatic masses. Design: Cross - sectional analytical (comparative study). Place and Duration: Department of histopathology, Sheikh Zayed Hospital, Lahore. Study period 1 year. Material and Methods: A total of 32 patients with solitary or multiple hepatic masses underwent FNAC from March 1999 to March 2000. Adequate aspirates were obtained in all these cases. Smears were stained with May-Grunwald Giemsa, Haematoxylin and Eosin and Papanicolaou stain. Needle biopsies from the same cases were also obtained and processed. These were stained with routine Haematoxylin and Eosin staining. The blood clots obtained during FNAC were fixed in 10% neu-tral buffered formalin. The histopathology of these blood clots was used for cases whose needle core biopsy was not available. The screened FNAC smears were divided into 3 categories i.e., benign (group - I), malignant (group - II), non-neoplastic / inflammatory lesions (including cysts and abscesses) (group - III). Results: Out of 32 cases, 6 were categorized as benign, 18 as malignant, and 8 as non-neoplastic inflammatory lesions. Three false negative diagnoses, including 1 for malignant tumour and 2 for benign tumours was obtained. There was 1 false positive diagnosis for malignancy. FNAC - histological correlation showed a 94.2% sensitivity and 92.3% diagnostic accuracy for malignant tumours, while benign tumours posed maximum diagnostic problems, giving a 66.67% sensitivity and 85.7% diagnostic accuracy. FNAC picked up correctly all the non-neoplastic lesions giving a 100% sensitivity and diagnostic accuracy. Conclusion: Majority of the malignant tumours can be categorized on FNAC, with a high degree of accuracy, while benign tumours should be subjected to biopsy, as there is a relatively greater possibility of false negative diagnosis. (author)

[en] The scope of microautoradiography as a cytological technique is briefly outlined. Established metabolic pathways and molecular structures provide numerous possibilities for generating radiochemicals which can serve as specific biochemical markers in microautoradiography. The anatomical discrimination available depends on the thickness of the specimen, the range of the radiation creating the image, the size of the emulsion crystals and the type of development process used. The most highly discriminating systems reveal and quantify radioactivity in small organelles and membranes within individual cells. More crudely used, the method reveals the activity in individual cells among a population or particular local areas of extracellular matrix. Image deconvolution techniques are currently being explored to improve the anatomical and chemical discrimination in the autoradiographic examination of solitary free cells. (U.K.)

[en] In this note an experimental set-up and mathematical procedure are presented using a commercially available cell counting system from E Leitz GmbH and Bosch Fernseh-Anlage GmbH, Darmstadt. It was possible to count clones of V79 Chinese hamster cells or clones of other cell lines automatically with an accuracy of ± 5% if the following conditions are fulfilled. (i) The clones are randomly distributed (ii) An isotropic illumination provides a correct picture. (iii) The counting system counts the number of single or overlapping clones and measures the degree of coverage. Under these conditions, the fraction of overlapping objects can be determined theoretically from the coverage, and the final count number can be corrected for overlapping clones. (UK)

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[en] Fine needle aspiration cytology (FNAC) has been used extensively in the U.K. for the diagnosis of breast lesions over the past 15 years. More recently, large gauge needle biopsy has been used to address many of the problems which have been encountered with fine needle aspiration. This paper reviews the evolution of the use of these procedures and the advantages and disadvantages of each. In considering whether to abandon the use of fine needle aspiration cytology in breast assessment, each individual unit should make a decision based upon their own audited results. However, even if FNAC is retained, it is important to be able to complement cytological diagnosis with core biopsy as there are indisputable advantages, e.g. in the diagnosis of mammographically detected microcalcification. As always, a multi-disciplinary approach is ultimately essential for effective patient management. Litherland, J.C. (2002)