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Biomedical subjects

L G Koss

Publications and source records attributed to L G Koss.

At least 271 records · Page 15Linked to original sources
PubMedDate not supplied

Value of aspiration cytology of the thyroid in metastatic disease.

Metastases may simulate primary malignant tumors of the thyroid, causing problems in the diagnosis and management of patients with a history of cancer. In the seven-year period of July 1978 through June 1985, 8 of 549 needle aspirates of the thyroid contained metastatic tumor, 6 of which were subsequently confirmed by histologic study. The primary sites of origin were the breast, kidney, colon and stomach as well as lymphoma. The cytologic features observed in the aspiration biopsy material from the six cases were characteristic of each of the primary tumors. Three of the patients had had prior resections of carcinomas (breast, colon and stomach) while in three patients the cytologic diagnosis of the thyroid aspirates led to the discovery of the primary tumor (kidney and two lymphomas). One case of lymphoma/leukemia and one case of previously biopsied lung carcinoma were confirmed on clinical grounds. It is of critical importance that primary thyroid neoplasms occurring in patients known to have primary tumors elsewhere be distinguished from disseminated tumors involving the thyroid. Our experience suggests that fine needle aspiration is of considerable value in this differential diagnosis. Needle aspirates of the thyroid are also of value in leading to the diagnosis of unsuspected nonthyroidal primary cancer.

Adult↗
PubMedDate not supplied

Computer discriminant analysis of atypical urothelial cells.

Prior computer studies of digitized cell images by the TICAS system have shown that the category of urothelial cells classified visually as atypical may be composed of 2 subgroups, one clustering mainly with benign cells and the other with malignant cells. As a consequence, a visual review of the group of atypical cells was conducted and tested by computer discriminant analysis. The computer classification confirmed the visual reclassification and subdivision of atypical urothelial cells into 2 subgroups, ATY I and ATY II. This is yet another example of feedback from computer diagnosis to visual assessment of cells. The significance of these observations in terms of diagnosis will be the subject of subsequent communications.

Computers↗
PubMedDate not supplied

Indices of cell atypia in urinary tract cytology.

A sample profile based on assessment of digitized cell images of normal (NEG), malignant (POS) and two classes of atypical (ATY I and ATY II) urothelial cells was established. Data distributed in a multidimensional feature space were projected into a two-dimensional display space using linear discriminant functions as composite features. Fitting of a polynomial led to the derivation of an atypicality index for each cell and to statistically clearly significant differences in the atypicality values for the four groups of urothelial cells. The application of these findings to patients' profiles will be examined in a subsequent communication.

Computers↗
PubMedDate not supplied

Diagnostic cytologic sample profiles in patients with bladder cancer using TICAS system.

Computer analysis of digitized cell images was applied to consecutively encountered, well preserved urothelial cells in the urinary sediment of 12 patients with bladder cancer. It was shown that the composition of the cell sample, and notably the proportion cells classified in the ATY II and POS (malignant) categories, were of diagnostic significance. This work indicated that a computer-generated diagnosis based on the cells in a urinary sample could probably be achieved with a relatively small number of urothelial cells. The study also suggested that computer-generated cytologic profiles of patients with non-papillary carcinoma in situ can be distinguished from other forms of urothelial cancer. The atypicality indices computed for all cells from each patient provided important information but were per se insufficient for diagnostic purposes. This preliminary study, based on a small group of patients, suggests that high resolution scanning offers a promising approach to automation of cytology of the urinary sediment.

Carcinoma↗
PubMedDate not supplied

Diagnosis of early endometrial cancer and precancerous states.

After a brief epidemiologic survey of endometrial cancer, the subject of detection and diagnosis of early lesions is addressed. Emphasis is placed on major gaps that exist in the knowledge of natural history of the disease. Cytologic and histologic detection and diagnostic techniques are reviewed and their advantages and disadvantages discussed.

Adult↗
PubMedDate not supplied

Diagnostic value of cytology of voided urine.

Cytologic examination of the sediment of voided urine is the only noninvasive method of detection, diagnosis and follow-up of tumors of the bladder and other anatomic components of the lower urinary tract. In order to assess the value of cytology of voided urine, we analyzed the diagnostic yield in 203 episodes, each composed of three sediments of voided urine obtained on consecutive days. For each one of these episodes, histologic material was available and was reviewed. Of special interest were 181 instances of primary or recurrent bladder tumors; in 37 of these patients, random biopsies of the bladder were also available for review. The concept of intraurothelial neoplasia (IUN), graded I, II or III, was introduced to describe degrees of atypia in flat urothelium, with IUN grade III corresponding to nonpapillary carcinoma in situ. The results documented that cytology of voided urine is highly reliable in the diagnosis of high-grade tumors, with a sensitivity of 94.2%. In primary flat carcinoma in situ (IUN III), the sensitivity was 100%. The method failed in the recognition of grade I papillary tumors and in about one-third of grade II tumors. There were no false-positive results in this study. In the 151 positive cases, the cytologic diagnosis was established on the first specimen in 79%, on the second specimen in an additional 14% and on the third specimen in 7% of cases. These results justify the use of three consecutive daily urine specimens for optimal diagnostic results. There is a remarkable similarity between the presence of cancer cells in voided urine and the DNA ploidy of bladder tumors, as established by Tribukait. The observations reported herein suggest that positive urine cytologies may correspond to aneuploid tumors and hence be not only of diagnostic but also of prognostic value. A direct proof of this hypothesis is under investigation; the results of this study justify the need for a field trial of an automated image analysis diagnostic system that was developed in this department.

Carcinoma↗
PubMedDate not supplied

A simple method of preparation and identification of cells for scanning electron microscopy.

A simple and inexpensive method of cell preparation for scanning electron microscopy (SEM) is described. This method allows for rapid identification of the same cells under the light microscope and by SEM. The method does not perceptibly alter the ultrastructural surface features of target cells. It is applicable to all cells in suspension, and its performance has been tested on human urinary sediment and effusions.

Cytodiagnosis↗
PubMedDate not supplied

Urinary cytology: the subjective diagnostic clues and their evaluation by computer.

Subjective diagnostic clues of cells contained in the urinary sediment are summarized and correlated with the clinical data. The rationale, techniques and strategy of the automation process for cells in the urinary sediment are discussed. The encouraging preliminary results of the application of a high-resolution approach to automation by the TICAS system are briefly presented.

Carcinoma in Situ↗
PubMedDate not supplied

Thin needle aspiration biopsy of endocrine organs.

The purpose of this paper is to summarize the advantages and disadvantages of the fine needle aspiration technique in reference to the endocrine organs. The principles of technique and interpretation are presented. The application of aspiration biopsies to the breast, the prostate, the pancreas and the thyroid are briefly discussed.

Biopsy↗
PubMedDate not supplied

Configuration of surfaces of human cancer cells obtained by fine needle aspiration biopsy: a comparative light microscopic and scanning electron microscopic study.

The surface configuration of human cancer cells removed from their natural setting by fine needle aspiration biopsies was studied by scanning electron microscopy. Cells from several carcinomas of the breast, malignant melanomas, oat cell carcinomas and a malignant lymphoma were the subject of this study. Only viable cells, identified by light microscopy prior to scanning, were selected for study. Contrary to prior observations on cancer cells in effusions, the surface configuration of human cancer cells obtained directly from tissues is variable and may depend significantly on the histologic patterns.

Breast Neoplasms↗