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G Steineck

Publications and source records attributed to G Steineck.

At least 73 records · Page 4Linked to original sources
PubMed1995

Hormone-refractory (D3) prostate cancer: refining the concept.

OBJECTIVES: A wide range of responses have been reported to second-line hormonal therapies, including corticosteroids and the withdrawal of antiandrogens in patients with hormone-refractory prostate cancers. This suggested the need to classify patients on the basis of hormonal sensitivity. A schema was developed by assessing the differences in entry criteria in relation to outcomes for clinical protocols with hydrocortisone alone or in combination with other agents for patients who had progressed after primary hormone therapy. METHODS: Published clinical trials of patients who had progressed after primary hormone treatment, which included glucocorticoids, were retrieved from Medline listings. The trials included patients treated with hydrocortisone alone, hydrocortisone and aminoglutethimide, hydrocortisone plus suramin, dexamethasone, and prednisone alone or in combination with chemotherapy. RESULTS: The definitions used for refractory disease ranged from none, to "progression", to "unsuccessful second medical or surgical castration. "None of the trials included a definition for hormone-refractory disease based on objective criteria. Details were lacking on most trials with respect to the response to and specific types of hormonal therapies. Furthermore, few trials controlled for the potential contribution of the "flutamide withdrawal syndrome" on outcome. CONCLUSIONS: The term "hormone-refractory" prostate cancer has evolved to include patients with a spectrum of diseases. As utilized in clinical trials of second-line hormonal therapies, patients who have received one and as many as six different treatments have been included in the same study. A new classification of patients based on hormonal sensitivity is proposed to recognize that androgen-independent proliferation, progression of disease despite castrate levels of testosterone, does not necessarily mean that a tumor is refractory to hormonal manipulations. Future trials in hormonally relapsed patients must include more details of the hormonal therapies utilized.

Aminoglutethimide↗
PubMed1995

Effect of cooking temperature on the formation of heterocyclic amines in fried meat products and pan residues.

Frequent consumers of meat have an increased risk of colorectal cancer and possibly also of breast, stomach, pancreas and urinary bladder cancer. Bacon, 'Falusausage', ground beef, meatballs, pork belly, pork chops and sliced beef account for more than one-third of the intake of fried meat of the population of Stockholm of age 50-75. These dishes were fried at four temperatures (150, 175, 200 and 225 degrees C) representing normal household cooking practices in Stockholm. Heterocyclic amines in these dishes were analysed using solid-phase extraction and HPLC. The heterocyclic amines 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were recovered. The formation of IQ was favoured by moderate cooking temperatures; IQ was detected in one meat sample cooked at 150 degrees C and in some pan residues. The yield of MeIQx, DiMeIQx and PhIP increased with the temperature. For several of the meat dishes, the content of heterocyclic amines in the pan residue was as large or larger than for corresponding piece of meat. The highest levels of MeIQx were 23.7 ng/g in the meat and 23.3 ng/g in the pan residue. Corresponding data for DiMeIQx were 2.7 and 4.1 ng/g and for PhIP 12.7 and 82.4 ng/g. The study leaves little doubt that mutagenic heterocyclic amines are ingested by the population of Stockholm, and added to previous epidemiological studies from the same area, the combined data are consistent with human carcinogenicity of heterocyclic amines. However, analytical epidemiological studies are needed before any statement on causality can be made.

Aged↗
PubMed1995

Acetaminophen, some other drugs, some diseases and the risk of transitional cell carcinoma. A population-based case-control study.

The purpose of this study was to investigate the risk of transitional cell carcinoma among subjects with an intake of acetaminophen, aspirin, some other drugs and with some intercurrent diseases. The source person-time ('study base') included subjects living in Stockholm in 1985-1987. The study included 325 subjects with a transitional cell carcinoma of the urinary tract and 393 controls randomly selected from the source person-time. Data were obtained by a postal questionnaire supplemented by a telephone interview. A relative risk (with a 95% confidence interval) of 1.6 (1.1-2.3) was obtained after an intake of acetaminophen, adjusted for age, aspirin, gender and smoking. Conversely, a 30% decrease in risk was obtained after an intake of aspirin. No details in the exposure substantiated the finding for acetaminophen. The inherent validity problems of observational studies, and the weak evidence in this and previous studies of the association between acetaminophen and transitional cell carcinoma, makes available epidemiological evidence insufficient to regulate the use of this commonly ingested analgesic. Increased risks were, in addition, found for tetracyclines, nitrofurantoin and a history of allergic asthma and a decreased risk found for rheumatic symptoms. The findings stress the nonepidemiological data concerning the potential carcinogenicity of acetaminophen and may be a foundation for future research of some other drugs and diseases.

Acetaminophen↗
PubMed1994

Intake of fried meat and risk of cancer: a follow-up study in Finland.

It has been suggested that mutagens in fried meat may be involved in the cancer process. Therefore the relationships between intake of fried meat and subsequent risk of cancers at different sites were studied among 9,990 Finnish men and women, 15-99 years of age and initially free of cancer. The baseline study was carried out in 1966-1972, and cases of cancer were identified through data linkage with the Finnish Cancer Registry. During a 24-year follow-up, 853 cancer cases were diagnosed. The intake of fried meat was estimated from a dietary history interview covering the total diet of the participants during the previous year. There was a positive association between fried meat intake and the risk of female-hormone-related cancers, i.e., cancer of the breast, endometrium and ovary combined. The relative risk of these cancers combined between persons in the highest and lowest tertiles of daily intake of fried meat adjusted for age, personal characteristics and intake of other main food groups was 1.77 (95% confidence interval = 1.11-2.84). Pancreatic and nervous system cancers also presented non-significant suggestive associations. No associations were observed with respect to other single cancer sites studied or to all sites of cancer combined. Further epidemiological efforts are needed to ascertain the potential link between fried-food mutagens and cancer risk.

Adolescent↗
PubMed1994

Delayed chemotherapy-induced nausea is augmented by high levels of endogenous noradrenaline.

The relation between pretreatment night-time urinary catecholamine excretion and chemotherapy-induced nausea and vomiting was studied. The first cohort included 17 women and three men with various cancer forms receiving low or moderately emetogenic chemotherapy. The second cohort included 42 women receiving cisplatinum (50 mg m-2) for ovarian cancer and ondansetron as an antiemetic (8 mg i.v. x 3 at chemotherapy and 8 mg p.o. x 3 for 5 days). Relatively higher noradrenaline, but not adrenaline, excretion was associated with an increased intensity of delayed nausea following treatment. Vomiting was not consistently related to the excretion of either catecholamine. The results indicate that noradrenaline modulates delayed nausea resulting from chemotherapy.

Adult↗
PubMed1993

Recent results of management of palpable clinically localized prostate cancer.

BACKGROUND: There is uncertainty regarding if, when, and how localized prostate cancer should be managed. METHODS: To examine evidence of a beneficial effect of aggressive treatment on metastatic failure and disease-specific mortality in clinically localized prostate cancer, the authors compiled data from the literature since 1980 regarding radical prostatectomy, external radiation therapy, and deferred treatment. RESULTS: The weighted mean of reported disease-specific survival at 10 years was 93% for radical prostatectomy, 83% for deferred treatment, and 74% for external radiation therapy. To broaden the database we have also computed, from the recorded number of patients who died of prostate cancer and the number of person-years at risk, a calculated disease-specific survival at 10 years of 93% for radical prostatectomy, 83% for deferred treatment, and 62% for external radiation therapy. The data suggest a favorable treatment effect with regard to disease-specific mortality for radical prostatectomy, but not for external radiation therapy at 10 years of follow-up. This observation must be tempered by the absence of convincing randomized trials and by the possibility of selection biases in the reviewed studies. CONCLUSIONS: As judged from our analysis, clinically localized prostate cancer often has a protracted course associated with a significant competing mortality and marginal benefit from radical prostatectomy at 10 years in terms of the endpoints used.

Adult↗
PubMed1993

Methodology and utility of a job-exposure matrix.

We have previously reported a study in which a job-exposure matrix was applied to census data, identifying, e.g., polychlorinated biphenyls (PCBs) and creosote as increasing the risk of urothelial cancer. In this article, we expand on some theoretical issues, and present detailed accounts of constructed linkages for PCBs, creosote, and phenols. For agents of interest, one should emphasize the positive predictive value rather than the sensitivity in the construction of the matrix. The reverse is true for confounding factors; to avoid residual confounding after restriction to subjects unexposed for the confounding factors, one should emphasize sensitivity, possibly compromising the positive predictive value. This discrepancy between agents of interest and confounding factors may limit the application of a general matrix for studying several different diseases. The construction of the matrix is much harder, if sensitivity rather than positive predictive value is emphasized for an agent. Confounding from industry-related agents arises due to a true mixed exposure in certain work tasks, but also due to a gross classification of occupations in the census. One should not confuse different levels of the positive predictive value with exposure dose. A "dose-response" with different levels of positive predictive value reflects an accuracy of the matrix, not a biological phenomenon. Studies with exposure information from a job-exposure matrix applied to registers with scant information on occupation and industry may be warranted for exposures and diseases for which previous studies with a detailed documentation of exposure have low precision.

Cohort Studies↗
PubMed1993

The epidemiological evidence concerning intake of mutagenic activity from the fried surface and the risk of cancer cannot justify preventive measures.

In the fried meat surface layer (the meat crust) mutagenic heterocyclic amines are formed during cooking. A human cancer risk is conceivable after intake of such mutagenic activity. We investigated the current literature mentioning fried foods, and six studies of colorectal cancer, three of stomach cancer and one each of cancer of the breast, lower urinary tract and pancreas are included. None of the reports tried to assess directly the intake of mutagenic activity from the fried surface. One indirect measure of mutagenic activity is to look at the browning of the meat surface; two investigations are available for this variable. The content of mutagenic activity in the surface may vary with the 'doneness' of meat and two studies consider this variable. Another indirect measure is to compare results from meat irrespective of cooking methods (ie, comparing meat not fried with fried meat or fried foods). There are several validity problems in the reviewed studies. Major potential sources of bias include, quite apart from misclassification of mutagenic activity, possible confounding factors from meat per se and fat. The epidemiological evidence in the field is sparse and cannot justify preventive measures.

Colonic Neoplasms↗
PubMed1993

Conditioned nausea after cancer chemotherapy and autonomic nervous system conditionability.

There are marked individual differences in conditioned nausea after cancer chemotherapy. To examine if part of this variation is associated with individual differences in autonomic nervous system conditionability, the present study addressed whether patients with conditioned nausea acquired conditioned heart rate and electrodermal responses at a different rate than patients without conditioned nausea. Of 28 relapse-free patients who had completed cisplatinum treatment for testicular cancer between 1981 and 1986, 10 reported persistent conditioned nausea, 8 extinguished conditioned nausea and 10 no conditioned nausea. These three groups were subjected to a differential conditioning paradigm with 8 sec pictorial stimuli (circles and triangles) serving as conditioned stimuli for an unconditioned electric shock while heart rate and electrodermal activity was monitored. There were 4 habituation, 8 acquisition and 8 extinction trials with each of the two cues. Analyses of variance using nausea status as the independent variable and physiological responses as the dependent lended some support to the notion that conditioned heart rate deceleration developed in response to the reinforced compared to the nonreinforced cue during acquisition in the two groups with persistent or extinguished conditioned nausea but not in the group with no conditioned nausea. In addition, patients that displayed good, as compared to poor heart rate conditionability during acquisition, were more likely to have persistent conditioned nausea, whereas those who showed poor heart rate conditioning mostly were those without conditioned nausea. Electrodermal variables revealed no systematic differences between groups. This tentatively supports that individual differences in parasympathetic but not sympathetic nervous system conditionability may be associated with individual differences in conditioned nausea resulting from cancer chemotherapy.

Adult↗
PubMed1992

Aspects of misclassification of confounding factors.

Misclassification of exposure in epidemiologic investigations has been extensively studied and is now well understood. In contrast, misclassification of confounding factors has been much less investigated. First, we consider a situation with confounding by age, in which misclassification is introduced through stratification of this inherently continuous variable. This misclassification turns out to be benign: 75% of the original confounding is removed by stratification into two age classes and more than 90% by using three age classes. Second, we consider a situation with serious confounding and serious misclassification of the confounding factor but no misclassification of the exposure. In this situation, the misclassification turns out to be of importance. After stratification for the misclassified confounding factor, it appears as though the exposure has a stronger effect on the incidence than the confounder, which is the reverse of the true situation.

Adult↗
PubMed1992

Occupational exposures and cancer of the colon and rectum.

The associations between occupational risks and colorectal cancer were examined in a Swedish population-based, case-referent study. The study was performed in Stockholm in 1986-1988 and included 569 cases and 512 referents. Relative risks (RRs) with 95% confidence intervals were calculated for different occupations/chemicals. Elevated risks of colon cancer were found among male petrol station/automobile repair workers (RR = 2.3, 0.8-6.6) and among males exposed to asbestos (RR = 1.8, 0.9-3.6), while elevated risks of rectal cancer were found among males exposed to soot (RR = 2.2, 1.1-4.3), asbestos (RR = 2.2, 1.0-4.7), cutting fluids/oils (RR = 2.1, 1.1-4.0), and combustion gases from coal/coke/wood (RR = 1.9, 1.0-3.7). However, due to a high correlation between the above-mentioned variables and the few exposed subjects, it is difficult to separate their effects properly. These analyses were adjusted for age. Further adjustments for diet, body mass, and physical activity had little or no influence on the results.

Adult↗
PubMed1992

Control of cisplatin induced emesis--a multidisciplinary intervention strategy.

A pharmacological, behavioural and nursing intervention strategy was evaluated for prevention of cisplatin (50 mg m-2) induced emesis in ovarian cancer patients. 46 patients received metoclopramide 2.5 mg kg-1 i.v., b.i.d., dexamethasone 20 mg i.v., lorazepam and biperiden as well as training in relaxation, nutritional advice and continuity in nursing care. Controls (n = 34) received standard treatment (metoclopramide 10-20 mg i.v. or dixyracin 20 mg i.v.). The intensity and duration of nausea and vomiting were significantly lower and measures of quality of life higher for patients on the experimental ward during the three cycles that were studied. No significant changes in emesis were observed between the cycles. There was no correlation between emesis and any of the parameters of quality of life measured. The reliability and validity of nausea ratings are discussed and we suggest that an underreporting of nausea and vomiting might be common.

Adult↗
PubMed1992

Conservative management of localized prostatic cancer.

Radical prostatectomy (RP), irradiation (RT), early endocrine therapy (EET), and expectant treatment (DT) are strategies for the management of clinically localized prostatic cancer. EET has not been systematically studied, but warrants prospective exploration. DT in uncontrolled studies results in disease-specific survival rates at 10 years that appear comparable to those achieved following RP or RT and may be considered a management option in patients with limited life expectancy. Serial observations in untreated patients provide a clinical indication of the rate of tumor progression, but better indicators of growth rate, metastatic potential, and responsiveness to a particular therapy are needed. Decision analysis may ultimately provide a practical supplement to clinical judgment in the choice of treatment.

Humans↗