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Biomedical subjects

G Auer

Publications and source records attributed to G Auer.

At least 145 records · Page 8Linked to original sources
PubMed1989

DNA evaluation in growth hormone producing pituitary adenomas: flow cytometry versus single cell analysis.

DNA patterns were analysed in 26 GH-producing pituitary adenomas by flow cytometry as well as by microspectrophotometry. Twelve tumours (46%) were diploid according to both methods, whereas 5 tumours (19%) showed aneuploid DNA patterns. Nine tumours were classified differently by the two methods: flow cytometry resulted in diploidy in 2 and aneuploidy in 7 patients, whereas microspectrophotometry showed diploidy in 5 tumours, tetraploidy in 3 and aneuploidy in 1. Methodological limitations may explain the discrepancy in the results obtained by the two methods. However, both the flow cytometry and the microspectrophotometry method show the presence of aneuploid DNA patterns in GH-producing pituitary adenomas despite their benign growth characteristics and the clinically benign course of the disease. This comparative study with two methods measuring DNA content, shows that depending on the criteria used for diploidy-aneuploidy, the frequency of aneuploidy will vary. In this material of 26 GH-producing adenomas, 46% were aneuploid according to flow cytometry and 23% according to microspectrophotometric. However, no correlation to tumour size or GH levels was found with either method when patients with aneuploid and diploid tumours were compared. Therefore, no clinical significance can so far be drawn from these results.

Acromegaly↗
PubMed1989

Nuclear DNA measurements on thyroid carcinoma in young patients.

Nuclear DNA measurements were performed on thyroid carcinomas from 36 patients aged 20 years or less. Histologic material from the tumors were stained according to the Feulgen technique and measured with slide cytophotometry. Thirty-two of the 36 tumors were of papillary type, 3 were medullary carcinoma and 1 was a follicular carcinoma. Of the 32 papillary carcinomas, 6 tumors (19%) were aneuploid and 26 (81%) were diploid, including 2 cases with lung metastases at diagnosis. Of the 3 medullary carcinomas, 2 were diploid and 1 aneuploid. The only follicular carcinoma was aneuploid. The patients were followed between 10 and 35 years, and 34 were alive at the end of the study. Two patients died, both had medullary carcinomas. One patient, with a diploid tumor, died during surgery. The other patient, with an aneuploid tumor, died 5 years after diagnosis of metastatic disease. Six patients had recurrences, all within 7 years. All the primary tumors and the corresponding recurrences showed a diploid DNA content. The results show that the majority of thyroid carcinomas in young patients exhibit diploid DNA profiles which is in agreement with the overall good prognosis in this patient category. However, since also patients with aneuploid tumors exhibited a similar good prognosis it seems that DNA measurements do not contribute additional prognostic information in young patients.

Adolescent↗
PubMed1989

Non-palpable invasive breast carcinomas from the Stockholm screening project.

Sixty-six non-palpable, invasive mammary adenocarcinomas from the Stockholm mammography screening project were studied with respect to histopathology. In 53 of these tumors estrogen receptor (ER) content was estimated and in 30 of them also the DNA distribution pattern. The tumors were predominantly of low or intermediate histological malignancy grade and ER-rich, whereas the distribution of DNA ploidy equalled that found in a non-selected tumor material. Only 2 tumors recurred during follow-up (median 51 months), indicating that non-palpable breast carcinomas represent a prognostically favourable subset in spite of a relatively high proportion of aneuploid tumors.

Adenocarcinoma↗
PubMed1989

Co-existent anaplastic and well differentiated thyroid carcinomas: a nuclear DNA study.

Clonal transformation of well differentiated follicular or papillary carcinomas has been suggested as a mechanism by which anaplastic carcinomas of the thyroid might arise. Of 126 cases of anaplastic (giant cell) carcinomas, 17 (13.5%) contained histologically well differentiated tumour foci within or adjacent to the high grade malignant anaplastic tumour. Cytophotometric DNA analysis after Feulgen staining was performed on 11 cases in order to evaluate ploidy of the anaplastic and the well differentiated tumour cells. The majority of these co-existent carcinomas (9/11) were papillary. All 11 anaplastic carcinomas demonstrated an aneuploid DNA pattern which correlated with a poor clinical outcome (7 of 11 died of disease in less than 6 months). In contrast six co-existent papillary and one co-existent follicular tumours were diploid. These data show that the co-existence of anaplastic and well differentiated carcinoma occurs only rarely and when it occurs only one third of the well differentiated tumours contain aneuploid tumour cells. This suggests that in the majority of cases of anaplastic thyroid carcinoma the malignant cells arise de novo rather than through clonal transformation of well differentiated carcinomas.

Adenocarcinoma↗
PubMed1989

DNA and nuclear protein characteristics in non-neoplastic and neoplastic endometrial tissue.

Feulgen-DNA and nuclear protein (NP) measurements were performed on non-neoplastic and neoplastic endometrium. Non-neoplastic endometrial cells were exclusively characterized by euploid nuclear DNA content. The NP content may vary significantly in relation to the proliferative stage as reflected by a 2-3-fold increase NP/DNA ratio in growing as compared to growth arrested cells. Endometrial adenocarcinomas could be subdivided into euploid and aneuploid types. The euploid tumors were found to exhibit DNA and NP characteristics comparable with those of normal tissue. In contrast, aneuploid tumors showed DNA and NP characteristics indicating increased proliferative activity as well as a pronounced disorder between the DNA and protein cycle.

Biomarkers, Tumor↗
PubMed1989

Nuclear DNA measurements in follicular thyroid adenomas.

The nuclear DNA content was measured retrospectively in histologically confirmed follicular adenomas in 20 patients, and prospectively in 25 patients. In the retrospective group two of the adenomas, and in the prospective group three of the adenomas were classified as atypical due to high cellularity and nuclear atypia, but with no sign of micro-invasive growth. In the group of patients studied retrospectively, the two patients with atypical adenoma had an aneuploid DNA pattern. One of these died 11 years after diagnosis with generalized disease. The other patient in this group with an aneuploid atypical adenoma is alive, as are all the remaining 18 patients with diploid adenomas. In the prospective group there were five aneuploid tumours. The atypical adenomas were aneuploid in two cases and polyploid in one case. No patient in the prospective group has shown any evidence of recurrence so far. Although DNA measurements are of value in distinguishing between low and high malignant potential in invasive tumors, the prognostic information if no invasion is found is uncertain. The importance of examining an adequate number of tissue blocks from the capsular region is emphasized.

Adenoma↗
PubMed1988

Nuclear DNA content and prognosis in Hürthle cell tumours of the thyroid gland.

The prognostic value of nuclear DNA content in Hürthle cell tumours of the thyroid was studied in 23 patients with more than 10 years follow up. Eleven of these neoplasms were classified as Hürthle cell carcinoma and 12 as adenoma. DNA measurements in morphologically identified single tumour cells were performed either on fine needle aspiration biopsy material or on histological sections from the primary tumours. The nuclear DNA content identifies those patients with a good versus a bad prognosis. These results correlate well with the findings in earlier studies about papillary, follicular and medullary thyroid tumours.

Adenoma↗
PubMed1987

Prognostic significance of clinical stage, histologic grade, and nuclear DNA content in squamous-cell carcinoma of the anus.

Specimens from 47 cases of anal squamous-cell carcinoma were examined in Stockholm county (1978 to 1981) with respect to clinical stage (43 cases), histologic grade (41 cases), and DNA content of the tumor cells (31 cases). Follow-up ranged from four to seven years (median, 5.5 years). The increased mortality in advanced stage and high-grade lesions was significant. Analysis of DNA content showed that most tumors were aneuploid. No statistically significant effect of DNA content on survival could be demonstrated. Thus, histologic grade and clinical stage seem to be the best predictors of patient outcome in squamous-cell carcinoma of the anus.

Adult↗
PubMed1987

Fine-needle biopsy cytology and DNA analysis. Their place in the evaluation and treatment of patients with thyroid neoplasms.

Fine-needle aspiration allows sampling of tissues without surgical biopsy. This technique provides accuracy, speed, patient acceptance, and individual cells for the study of neoplasia. When this procedure is combined with DNA analysis, it is possible to obtain preoperatively additional diagnostic and prognostic information superior to that obtained by clinical and morphologic methods alone. This information is of utmost importance when planning appropriate treatment.

Biopsy, Needle↗
PubMed1987

Assessment of malignancy potential in mammary carcinoma in elderly patients.

Tumors of 89 women, aged 75 or above, that were operated on for primary mammary carcinoma were analyzed with regard to histologic type and differentiation, estrogen receptor (ER) content, and nuclear DNA distribution pattern. The majority of the tumors were invasive ductal carcinomas but a relatively high frequency of papillary and colloid carcinomas was also found. The cancers were predominantly ER-positive (87%) and diploid (70%), indicating a favorable response to anti-estrogens and slow tumor growth. Despite these characteristics, the prognosis of elderly women with mammary carcinoma is no better than that of other age groups, as shown in previous studies. Nonsurgical treatment is often preferable in very old patients. Analysis of DNA profile can provide additional information and prognostic guidance when selecting patients for endocrine therapy.

Age Factors↗
PubMed1987

Nuclear DNA content in squamous cell carcinoma, small cell carcinoma, and bronchiolo-alveolar carcinoma of the lung.

Nuclear DNA content in individual, morphologically identified tumor cells from 33 squamous lung carcinomas, 20 small cell lung carcinomas, and 10 bronchiolo-alveolar carcinomas were analyzed by means of cytophotometry on Feulgen-stained histologic and cytologic specimens. Twenty-eight of the squamous cell carcinomas and 17 of the small cell carcinomas had high and scattered DNA values, indicative of high malignancy potentials. None of the bronchiolo-alveolar carcinomas showed such high DNA values. These results are in line with clinical experience that squamous cell and small cell carcinoma are associated with rapid progression and death in patients, whereas bronchiolo-alveolar carcinomas have a more indolent course.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1987

Relationship between certain radiographic and biologic characteristics in breast cancer.

The relationship between mammographic appearance of microcalcifications and tumor stage, malignancy grade, estrogen receptor (ER) content and nuclear DNA pattern was studied in 92 mammary carcinomas. The results indicate that no complementary prognostic guidance can be obtained from the radiographic appearance of a tumor apart from a high probability of a spiculated cancer being ER-rich. The finding of a relatively high proportion of aneuploid and ER-poor carcinomas among tumors with microcalcifications indicates that this radiographic characteristic might be associated with increased growth potential.

Adult↗
PubMed1986

High-resolution 2-dimensional protein mapping of "diploid" and "aneuploid" mammary adenocarcinomas.

Two-dimensional-electrophoretic analysis has been applied to non-neoplastic mammary epithelium from eight healthy women, tumor tissue from eight "diploid" mammary adenocarcinomas, and tumor tissue from eight "aneuploid" mammary adenocarcinomas. Compared with non-neoplastic mammary epithelium, a slight numerical net non-neoplastic mammary epithelium, a slight numerical net increase of the protein spots was detected in "diploid" tumors and a marked increase in "aneuploid" tumors. Two prominent spots were present in all 16 malignant tissues examined and absent in all eight non-neoplastic tissues (silver staining method). The results suggest that a difference in the composition of cellular proteins exists both between non-neoplastic mammary cells and malignant tumor cells, and between "diploid" and "aneuploid" tumors.

Adenocarcinoma↗