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U Abel

Publications and source records attributed to U Abel.

At least 19 recordsLinked to original sources
PubMed1992

Chemotherapy of advanced epithelial cancer--a critical review.

This article is a short version of a report which presents a comprehensive analysis of clinical trials and publications examining the value of cytotoxic chemotherapy in the treatment of advanced epithelial cancer. As a result of the analysis and the comments received from hundreds of oncologists in reply to a request for information, the following facts can be noted. Apart from lung cancer, in particular small-cell lung cancer, there is no direct evidence that chemotherapy prolongs survival in patients with advanced carcinoma. Except for ovarian cancer, available indirect evidence rather supports the absence of a positive effect. In treatment of lung cancer and ovarian cancer, the therapeutical benefit is at best rather small, and a less aggressive treatment seems to be at least as effective as the usual one. It is possible that certain sub-groups of patients benefit from the treatment, yet so far the available results do not allow a sufficiently precise definition of these groups. Many oncologists take it for granted that response to therapy prolongs survival, an opinion which is based on a fallacy and which is not supported by clinical studies. To date, it is unclear whether the treated patients, as a whole, benefit from chemotherapy as to their quality of life. For most cancer sites, urgently required types of studies such as randomized de-escalations of dose or comparisons of immediate versus deferred chemotherapy are still lacking. With few exceptions, there is no good scientific basis for the application of chemotherapy in symptom-free patients with advanced epithelial malignancy.

Bias↗
PubMed1991

Mononuclear cells in peripheral venous blood of patients with Crohn's disease: preoperative status and postoperative course, influence of duration, activity and extent of disease.

In Crohn's disease (CD) the intestinal lesion is supposed to be the cause of the observed systemic immunologic changes. Based on this assumption, peripheral blood mononuclear cells (PBMC) are of specific interest as a possible indicator of intestinal activity of the disease. From 151 surgical patients CD3+, CD4+, CD8+, B cells, macrophages, leucocytes and the relative number of lymphocytes were analysed preoperatively and 10 days, 3 and 6 months postoperatively. The cell data were correlated with the main clinical data of disease. There was a highly significant preoperative increase of leucocytes, macrophages, CD8+, and B cells in the CD group, and a marked decrease of CD3+, CD4+ cells, and the relative lymphocyte count in the same group. Six months postoperatively, highly elevated macrophages, and leucocytes, and a depressed number of CD4+ cells were the only changes. The preoperative cell data did not correlate with the duration of illness, CDAI, localisation, and extent of the intestinal lesion nor did they correlate with any modality of preoperative drug treatment. Thus, the determination of PBMC characteristics in CD is only of limited value for routine diagnostic purposes. However, the persistence of some pathological values long after operation might be caused by residual microscopic lesions and thus reflect the intestinal process.

Adolescent↗
PubMed1991

Common infections in the history of cancer patients and controls.

The association between the frequency of manifest infectious diseases and cancer risk was investigated in a case-control study at Heidelberg, FRG. A total of 255 cases with carcinomas of the stomach, colon, rectum, breast, and ovary, as well as 255 population controls and 230 hospital controls were interviewed using a standard questionnaire. Controls were matched to the cases for age, sex, and region of residence at the time of the interview. A history of common colds or gastroenteric influenza prior to the interview was found to be associated with a decreased cancer risk. Thus the odds ratios for "three or more common colds per year (on average)" versus "no common cold within the last 5 years prior to the interview" were 0.18 (95% CI = 0.05-0.69) and 0.23 (95% CI = 0.06-0.89) relative to population controls and hospital controls, respectively. There was no apparent relationship between childhood infections or other diseases reported in the earlier history, and cancer risk. While the findings are supported by previous studies and fit well into the results of other fields of cancer research, a conclusive interpretation and biological explanation cannot yet be given.

Adult↗
PubMed1990

[Extent of psammoma carcinomas of the ovary--a clinical, DNA flow cytophotometric and morphometric image analysis study].

There is no agreement in literature on the biological behavior of psammoma carcinomas of the ovary. The majority of authors consider psammoma bodies to be the result of tumour regression, associating the occurrence of psammoma bodies with longer survival. On the other hand, several studies reveal a poor prognosis for psammoma carcinomas, similar to that of other epithelial malignant tumours. In our study, the psammoma body content in 174 serous carcinomas stage III/IV was morphometrically quantified by image analysis and the results correlated to survival time and progression time. In 20 carcinomas the psammoma body content was extremely high. In such cases, DNA flow cytometry revealed these tumours to be slowly-growing. The DNA index was 1.0 (DNA-diploid) and the number of S phases was low (max. 5.9%). The five year estimate survival was 50%, as opposed to 10% for other tumours. If no methods are available for cell kinetic analysis and for objectification and quantification of psammoma body content in serous carcinomas it is sufficient to make a semiquantitative assessment of the psammoma body content to differentiate tumours with longer survival from carcinomas of poor prognosis.

Cystadenoma↗
PubMed1989

Assessment of serial carcinoembryonic antigen: determinations to monitor the therapeutic progress and prognosis of metastatic liver disease treated by regional chemotherapy.

It is difficult, time-consuming, and expensive to evaluate the therapeutic efficacy of regional chemotherapy of metastatic liver disease by means of imaging procedures. Therefore it was the aim of this study to find out whether serial carcinoembryonic antigen (CEA) determinations yield reliable data on the therapeutic progress and the individual prognosis of these patients. Since there exists no generally accepted modality to assess CEA curves of patients receiving chemotherapy, we developed our own criterion and tested it in a group of 35 patients. For each patient an individual reference level (CEA-means) was fixed which was obtained as the arithmetical mean of serial CEA values taken during the first three courses of chemotherapy (reference time). On the basis of CEA-means the marker curves of the 35 patients could be divided into two groups. After the reference time the CEA values of group 1 (12 patients) never decreased below CEA-means. Survival of these patients was significantly (P = 0.00001) shorter than that of the 23 patients (group 2) who showed a decrease in their CEA curves below CEA-means after the reference time. Beyond this it could be observed that the improvement in survival was significantly greater in those patients who showed a CEA decrease below CEA-means for a prolonged period (3 months). This difference in prognosis is not an artefact due to different pretherapeutic conditions but is a sign of different responses to therapy. The decrease in CEA values below the individual reference level (CEA-means) is a certain sign of the efficacy of the chosen chemotherapy. A continuous rise of the CEA curve above CEA-means signifies an ineffective intrahepatic chemotherapy or extrahepatic tumor manifestation. In this case an intensive diagnostic workup of the patient and possibly a modification of the therapy are indicated.

Adult↗
PubMed1989

[Proliferation index, axillary lymph node status, hormone receptors and age as prognostic factors in primary breast cancer].

A total of 233 primary carcinomas of the breast (n = 68 nodal negative and n = 165 nodal positive) of 77 woman patients of less than 50 years of age and pf 156 women patients of 50 years of age or older were examined for the prognostic significance of a proliferation index (in vitro chemoresistance assay). The prognostic significance of the proliferation index (high vs low proliferation) is compared with other prognostic factors that have already been in clinical use (age, axillary lymph node status, oestrogen and progesterone receptor status). The total median observation period was 4.8 years (3-9.1 years). Determination of the proliferation index proved to be the most important prognostic factor both for premenopausal and postmenopausal, nodal negative and nodal positive primary tumours when assessing the total survival time and the time that remains free from recurrences. A simultaneous assessment of low proliferation index and positive hormone receptor as a so-called low-risk situation shows in comparison to a high-risk situation (high proliferation index, negative receptor status) the most pronounced differences. For premenopausal women (younger than 50 years of age) the hormone receptor status has no prognostic significance as far as our group of patients is concerned, whereas for women of 50 years of age or older the receptor status is of great prognostic relevance. Besides the lymph node status, the proliferation index shows in a Cox regression model the greatest prognostic importance for the further course of a primary carcinoma of the breast.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1989

[Prognostic significance of cell kinetic parameters of endometrial cancer].

In 120 patients suffering from carcinoma of the endometrium of a wide variety of histological types, conventional clinical and morphological criteria of prognosis were compared with the DNA index (DI) and the S-phase fraction. The cellular kinetics parameters were obtained via flow cytophotometry. Adenocarcinomas (n = 101) were more frequently DNA diploid and had a lower S-phase share (less than 5%) than adenoacanthomas, clear-cell carcinomas and malignant Müller's mixed tumors. There are close correlations between the conventional prognostic factors such as FIGO stage, relative tumor invasion depth, grading and oestrogen or progesteron receptor content and the DNA content or S-phase fraction. Carcinomas with a DI less than or equal to 1.1 (n = 83) and the S-phase fraction less than 5% (n = 77), have a significantly longer survival time and recurrence-free interval than DNA-aneuploid tumors with a high S-phase fraction. The studies underline the need to use flow cytophotometry in the prognostic assessment of the carcinoma of the endometrium. The method is superior to histological grading, since the results obtained can be objectively assessed.

Aged↗
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↗