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U Abel

Publications and source records attributed to U Abel.

At least 55 records · Page 3Linked to original sources
PubMed1988

[Principles for evaluating simple, diagnostic tests].

The fundamental terms in the evaluation of diagnostic tests are described and the differences to corresponding test parameters in clinical chemistry are emphasized. The derivation of a two-by two contingency table is explained in detail and basic characteristics of diagnostic tests, i.e. sensitivity and specificity as well as their independence of the prevalence (in the sense of a-priori-probability) is pointed out. The importance of the so-called predictive values is shown graphically, also the problem of selecting a cut-off-level (discrimination value) for the evaluation of quantitative data. The various attempts to find a single value for the description of a diagnostic test are discussed and it is stressed that there is no principal necessity to use other terms than those mentioned above. Nevertheless it is possible to give a prevalence-independent measure which has some additional advantages in rating and comparing simple diagnostic tests.

Diagnostic Tests, Routine↗
PubMed1988

Correlation of DNA flow cytometric results and other prognostic factors in primary breast cancer.

The percentage of cells in S-phase and DNA-ploidy have been measured in 300 primary mammary carcinomas by means of DNA-flow cytometry (FCM). The data were compared with the age and menopausal status of the patients as well as with the size, regional lymph-node involvement, histologic type, grade and concentration of estrogen (ER) and progesterone (PR) receptors of the tumors. A DNA-diploid distribution of the G0/1-peak was found in 37.6% of the cases. The mean percentage of S-phase fractions was 4.83. DNA-aneuploid tumors had significantly higher amounts of S-phase fractions (6.12%) than DNA-diploid tumors (2.66%). There was also a significant correlation between the DNA measurement data (DNA-ploidy and S-phase fractions) and histologic grade, as well as the content of ER and PR, but not between DNA-ploidy, S-phase fractions, tumor size (T) and evidence of axillary lymph-node metastases. DNA-FCM gives a biological characterization of the tumor in addition to the histopathologic examination. The method can be used as a routine procedure because of the reliability and reproducibility of the results as well as the short time needed for the measurements.

Age Factors↗
PubMed1988

Comparison of S-phase fractions measured by flow cytometry and autoradiography in human transplant tumors.

The 3H-thymidine labeling index (TLI) and the percentage of cells in the S-phase have been determined by autoradiography and by flow cytometry, (FCM), respectively, in six malignant tumors of human origin transplanted on athymic nude mice. The Dean and Jett model and the graphical model were used to determine the percent of S-phase cells by FCM. Cell cycle analysis was performed using 1) no correction for background; 2) an algebraic function for background correction; and 3) an exponential function for background subtraction. Each of these three data sets was evaluated using both the Dean and Jett model and a graphical model for the evaluation of DNA histograms. The S-phase fractions (SPF) were compared to the corresponding labeling index results. SPF without background correction were 1.54 times higher than the TLI. SPF, after correction using the algebraic model, were 1.29-fold higher than the TLI, whereas SPF obtained after background subtraction according to the exponential model were only 1.05-fold higher than the TLI. Student's t-test revealed significant differences between the mean TLI values (16.25 +/- 9.06) and the mean SPF obtained by FCM without background correction (mean 25.0 +/- 9.36, P less than 0.01), but not between the mean TLI values and the mean SPF percentages after algebraic (mean 21.0 +/- 10.29) and exponential background correction (mean 17.11 +/- 11.59), P greater than 0.05 each. There was no difference between the results obtained using the Dean and Jett model and those obtained using the graphic evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

[Flow cytophotometry parameters, hormone receptors and axillary lymph node status as prognostic factors in primary breast cancer].

The prognostic significance of DNA flow cytometric examinations of 247 patients (mean age 57 years; 27-84) with operable breast cancer was analyzed. The findings were compared with biochemically determined steroid-hormone receptors and lymph node status. Forty-two percent of the tumors were diploid and 58% aneuploid; 32% of them had a high S-phase portion (greater than 5%; definition by the crit-level method). S-phase fractions were lower in diploid than in aneuploid tumors (2.5 +/- 2.2% versus 5.5 +/- 3.4%). Both with diploid tumors as well as tumors with a low S-phase fraction (less than 5%), recurrence-free survival was better than with aneuploid tumors (p = 0.02) and tumors with a high S-phase fraction (p = 0.004). A direct proportional relationship was found between the S-phase fraction and the mean recurrence-free interval. As regards overall survival, no significant differences have been detected so far, either for diploid and aneuploid tumors or tumors with low and high S-phase fractions. Using the Cox regression model, the prognostic significance of ploidy status and S-phase, as new factors, independent of age, lymph node and steroid-hormone receptor status, is shown. DNA flow cytometry is suitable for routine clinical use and should be used in particular as an independent prognostic factor for planning and stratification in adjuvant therapeutic studies.

Adult↗
PubMed1987

Carcinoembryonic antigen, CA 19-9, and CA 125 in normal and carcinomatous human colorectal tissue.

In 115 primary colorectal carcinomas and 64 normal colorectal mucosa specimens the concentrations of carcinoembryonic antigen (CEA), CA 19-9, and CA 125 were measured. The determinations were performed in cytosols by use of radioimmunometric and enzymeimmunometric assays and related to the wet tissue weight. In the cancer tissue the CEA levels ranged from 5.5 to 1990 micrograms/g tissue and were significantly higher (P less than 0.0001) than those found in the normal mucosa (1.2-58.6 micrograms/g). The CA 19-9 content in carcinoma specimens (120-72660 U/g) was also significantly higher (P = 0.011) than in the normal mucosa (37-5800 U/g). In contrast, no significant difference of the CA 125 concentrations between the normal and the cancer tissue was found. The relative operating characteristic (ROC) curves for the three markers corroborate CEA as the marker superior to CA 19-9. On the other hand is shown that CA 125 is completely unable to discriminate between normal and cancer tissues. A decreasing CEA tissue concentration and an increasing dedifferentiation of colorectal cancers were significantly (P = 0.018) related with each other. Higher tumor stages implied significantly higher tissue marker values of CA 19-9 (P = 0.027) and CA 125 (P = 0.0008). The findings correspond quite well with serum examinations of the three markers which have been reported earlier.

Antigens, Neoplasm↗
PubMed1987

Modified replacement randomization.

We propose a slight modification of replacement randomization by imposing an imbalance criterion within a restricted range of patient entry numbers. The bound on imbalance is stated most simply in terms of the maximum allowable difference in treatment assignments at the end of the trial. For clinical trials in which two therapies are compared, we study, by means of computer simulations, the dependence of both selection bias and the mean number of randomization list replacements on the parameters defining the procedure.

Biometry↗
PubMed1987

[Phase III study of chemotherapy in low-malignancy non-Hodgkin's lymphomas: comparison of vincristine-vindesine combination chemotherapy].

In a phase-III study in non-Hodgkin's lymphoma of low malignancy we compared a combination therapy with vincristine (COP) with a vindesine combination (CEP). Remission rates, duration of remission and survival was favorable for the CEP combination without reaching the level of significance. The peripheral neurotoxicity of grade 2 and 3 according to WHO criteria was observed more frequently with vincristine. The vincristine-induced neurotoxicity in 6 patients was not impaired when a change was made to vindesine treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

[Significance of primary radical surgery for survival following treatment of breast cancer. Problems of interpretation of treatment results of prospective, nonrandomized studies exemplified by the Southwest Germany Breast Cancer Study].

In a prospective non-randomised trial 1642 patients were included. After a mean time of 10 years a follow-up analysis was performed. The importance of the radicality of the primary operative therapy of breast cancer should be evaluated. The mean 5 years survival rate was 67.3%, the 10 year survival rate 51.6%. Tumor stage and age had a highly significant influence on the survival rate. Patients with simple mastectomy had a lower survival rate as patients with radical mastectomy. This apparent difference was caused by a different age distribution in the therapy groups. Accordingly the mean life deficiency was the lowest in the simple mastectomy group. In a multiple hazard statistical analysis tumor stage and age showed a highly significant influence on the survival rate. The intraoperative radicality classification showed a significant correlation to the prognoses of the patients. The operative therapy itself had no significant influence on the survival rate of the patients.

Adult↗
PubMed1986

Experience with ifosfamide combinations (etoposide or DDP) in non-small cell lung cancer.

In all, 171 patients with histologically verified non-small cell lung carcinoma were treated with ifosfamide 2.0 g/m2 on days 1-5 in combination with (91 patients) etoposide 120 mg/m2 on day 1. Therapeutic regimens were repeated after 4 weeks. Supportive treatment with mesna (20% of the ifosfamide doses at 0, 4, and 8 h) was performed. Cisplatin treatment was supported by mannitol-induced diuretic hydration. The overall response rate of ifosfamide/etoposide was calculated to be 27%, with 1 complete and 24 partial remissions. The median survival time for all patients was 8.5 months, for responders 14 months (P less than 0.05), for patients with no change 9.5 months, and for patients with tumor progression 4 months. With ifosfamide/cisplatin, there were 4 complete and 21 partial remissions (response rate 35%). The median survival time for all patients was 8.3 months, for responders 11.5 months, and for patients with tumor progression 4 months. Age, sex, and histological tumor type had no significant effect on survival. Patients with better performance stage and limited disease lived significantly longer. The main side-effects of the cisplatin combination were vomiting, bone marrow depression, and neuropathy. The etoposide combination was tolerated better. Urotoxicity was not significant, as a consequence of treatment with mesna. The results show that the combination ifosfamide/etoposide or ifosfamide/cisplatin are effective in the treatment of non-small cell lung cancer, being comparable to other combinations of etoposide/cisplatin and vindesine/cisplatin. Because of the better tolerability, the combination ifosfamide/etoposide is superior to cisplatin combinations.

Adenocarcinoma↗
PubMed1986

[Effect of intestinal resection on the behavior of mononuclear subpopulations in Crohn disease].

The literature data about the distribution of mononuclear cells in Crohn's disease are still contradictory. In 50 surgical C.D. patients, clinically classified corresponding to the Crohn's Disease Activity Index (CDAI), the T-lymphocytes and their subsets helper-T- and suppressor-T-lymphocytes (TH/TS) were therefore determined by use of monoclonal antisera, the B-lymphocytes by F(a b)-anti human Ig and the macrophages by uptake of latex microparticles. 37 C.D. patients underwent diseased bowel removal. Blood was drawn from the Crohn-draining mesenteric vein for analysis. Further investigations were performed at the 10th p. op. day as well as after an average period of 7 months (2-18). In comparison the mononuclear cell distribution was examined in 14 patients suffering from chronic osteitis and in 14 patients without any inflammatory disease as controls. C.D. patients showed preoperatively a significantly decreased TH/TS-ratio as well as a significantly increased proportion of macrophages. There was a lymphocytopenia in the peripheral differential blood count. Whereas the distribution of mononuclear subpopulations in the mesenteric blood was identical to the peripheral blood, significant lymphocytosis in the differential blood count of mesenteric blood was found. On the 10th p. op. day the TH/TS-ratio rose almost up to normal, which continued during the follow-up period. The macrophages remained constantly increased in all stages of investigation although during the follow-up none of the patients had signs of disease recurrence. Osteitis patients showed a similar distribution as C.D. patients, even if the changes compared to controls were not as distinct. The proportion of B-lymphocytes was the same in all groups examined. The individual TH/TS-ratios and proportions of macrophages of C.D. patients did not correlate to their clinical data. The changes within the T-cell-subpopulations seem to reflect less M. Crohn's disease itself than its inflammatory complications. Further studies have to be undertaken concerning the impact of the constant increase in macrophages, even after resection of the Crohn bearing bowel segment.

Adolescent↗
PubMed1986

Prospective randomized trial concerning hyper- and normoprolactinemia and the use of bromoergocryptine in patients with metastatic breast cancer.

This prospective trial was designed to help in selecting therapy for patients with elevated and normal plasma prolactin. Ninety-two patients entered this trial, of whom 86 were evaluable for final analysis. Hyperprolactinemic patients (n = 31) were randomized to receive VAC/FMC chemotherapy with or without bromoergocryptine. Normoprolactinemic patients with 'low risk' metastatic disease (disease-free interval greater than 30 months, ER/PR positive or unknown) were treated with medroxyprogesterone acetate or VAC/FMC chemotherapy. Normoprolactinemic 'high risk' patients (n = 42) (disease-free interval less than 30 months, EP/PR negative) received VAC/FMC chemotherapy with or without medroxyprogesterone acetate (MAP). The results show that bromoergocryptine does not improve response rate, duration of response and survival. Median survival of patients with elevated basal plasma prolactin (greater than 15 ng/ml) is reduced to 9 months compared to patients with normal basal plasma prolactin (17 months, log-rank p = 0.005). Unexpectedly, TRH stimulation proved inappropriate to separate normo- and hyperprolactinemic patients in terms of survival. Normoprolactinemic 'low risks' (tamoxifen failures) were observed to qualify for further hormone therapy (median survival 21+ months). Normoprolactinemic 'high risks' showed median survival of about 12 months with no apparent benefit for those receiving MAP, additionally. The results suggest that basal hyperprolactinemia, disease free interval, ER/PR receptor status, and liver metastasis are important prognostic variables. Endocrine and cytotoxic chemotherapy should be selected according to these risk factors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

The contribution of polycyclic aromatic hydrocarbon fractions with different boiling ranges to the carcinogenic impact of emission condensate from coal fired residential furnaces as evaluated by topical application to the skin of mice.

Flue gas condensate from briquet-fired residential furnaces was separated into a polycyclic aromatic compound (PAC)-free and a PAC-containing part, followed by a subfractionation of the PAC-containing fraction into 3 parts: PAC consisting predominantly of (a) 2 and 3 rings, (b) 4 and 5 rings and (c) 6 and more rings. To evaluate the carcinogenic potency of the condensate and its fractions, local application onto skin of mice in 2 or 3 doses was used. Since it was known from an earlier investigation that both the PAC-free fraction and the fraction containing PAC with 2 and 3 rings were almost ineffective, only PAC-fractions containing more than 3 rings were tested. The probit and Weibull analysis of the results showed that the condensate and the fractions containing PAC with 4 and 5 rings as well as 6 and more rings provoke local tumors after repeated application to the dorsal skin of mice. The tumor incidence exhibited a clear cut dose-response relationship. Fractions (b) and (c) were almost equally active, each contributing by about 50% to the total carcinogenicity. The content of benzo[a]pyrene (0.72 mg/g condensate) contributed by 10-11% to the total carcinogenicity of the emission.

Administration, Topical↗
PubMed1985

DNA flow cytometry of ovarian tumors with correlation to histopathology.

Tissue samples from 49 women with seven benign and 42 malignant ovarian tumors were examined by means of DNA flow cytometry (FCM). The FCM data (DNA-ploidy and the number of S-phase fractions) were compared with the International Federation of Gynecology and Obstetrics (FIGO) stage, the histologic grade of differentiation and in some cases with the clinical outcome. The benign ovarian tumors were all diploid with a mean of 2.1% (+/- 1.66) S-phase fractions. Adenocarcinomas with the histologic grade 1 were diploid and had a mean of 2.1% (+/- 1.17) S-phase fractions. Grade 2 adenocarcinomas were aneuploid in eight of nine cases and revealed an increased proliferative activity (7.7% +/- 2.67 S-phase fractions). A high number of aneuploid cases (nine of 13) and an increased DNA synthesis were found in grade 3 adenocarcinomas (12.0% +/- 5.72 S-phase fractions). Four of six malignant nonepithelial tumors also had high numbers of S-phase fractions (9.7-14.5%). A significant correlation between the histologic grade and the DNA synthesis, FIGO stage, and DNA-ploidy was found. DNA-FCM may be used as an additional diagnostic tool supplementing routine histopathologic examination of ovarian tumors for better biological characterization, especially for those with uncertain grading, for grade 2 neoplasms, and for malignant nonepithelial tumors.

Adenocarcinoma↗
PubMed1984

[Chemotherapy of the non-small cell carcinoma of the lung with ifosfamide and cisplatin].

80 patients with inoperable non-small cell bronchial carcinoma were treated, at an interval of 4 weeks between them, with ifosfamide (2 g/m2 on days 1-5) and cisplatin (75 mg/m2, day 1). All diagnoses had been confirmed histologically. The course of 72 patients (36 with squamous carcinoma, 25 with adenocarcinoma, two with alveolar-cell carcinoma and nine with large-cell carcinoma) could be evaluated. There were four complete and 21 partial remissions (response rate 35%). In a further 14 patients temporary arrest of tumor growth was registered. Median survival time of all patients was 8.3 months, for those with complete and partial remission 11.5 months. Patients in whom the tumor progressed lived on average 3.9 months. Age and general state of the patients, as well as histological tumor type, had no influence on the results of treatment. Patients in stage IV lived, at seven months, significantly less long than those with only loco-regional spread (11 months). Main side-effects were vomiting, bone-marrow depression and neuropathy. Urotoxicity was not significant, as a result of treatment with mesna. Remission rate and survival time of these patients corresponded with the results obtained with other cisplatin combinations.

Adenocarcinoma↗