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L Holmberg

Publications and source records attributed to L Holmberg.

339 records · Page 19Linked to original sources
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Future prospects of population-based mammographic screening.

Mammographic screening is one worthwhile way of reducing deaths from breast cancer among women diagnosed in ages 50-69. Our knowledge is less clear for women below 50 and above 70. Major research issues include whether by new approaches we can achieve a definitive mortality reduction in women under 50 and investigations of the efficacy of screening in the elderly. The optimal interval time has yet to be decided. When screening is taken to previously unscreened populations, effects on many parameters have to be followed, e.g., sensitivity, specificity, positive predictive value, gains, and costs. We do not as yet know what the implications of finding large numbers of women with in situ cancer are. Keeping high standards in population-based programs also means fighting potential drawbacks: minimizing the proportion of "unnecessary" biopsies and anxiety, avoiding over-treatment of cancers with excellent prognosis, preventing false reassurance or that women with suspicious findings are left without advice. Potential drawbacks of screening are best dealt with within a team of specialists on breast cancer diagnosis and treatment. Mammographic screening has become widely accepted as one important way of reducing breast cancer deaths, and this success has been dependent on the fact that its development has been science driven. To continue to develop, the tradition of critical evaluation and unsentimental bold testing of new ideas has to be carried on.

Adult↗
PubMedDate not supplied

The biology and natural history of breast cancer from the screening perspective.

A review of the tumor biology of breast cancer from the screening perspective reveals important research issues. It is not known if the induction phase includes any detectable preneoplastic lesions. Evidence for the existence of preneoplasias is conflicting. The effect of removal of such lesions on the incidence of breast cancer has not yet been studied. The mechanisms that govern progression of in situ lesions--or even small preclinical invasive cancers--are not fully understood. It is not clear to what extent progression into cancers with metastatic behavior occurs. Current predictors for progression are weak. One major benefit of the scientific evaluation of the screening programs is that we can learn more about the natural history of the disease. Mammographic screening detects tumors that are smaller in size than those detected by clinical examination only. There is an inverse relationship between tumor size and the probability that the patient has acquired axillary metastases. These facts, taken together, indicate that the mortality reduction seen in screening is a result of a real impact on the natural history. Calculations of the lead time gained in randomized screening projects give empirical proof that a third of the cancers progress from a localized stage to a disseminated disease relatively late in the preclinical phase of the tumor. Analyses of interval cancers in screening have pointed to the conclusion that the net growth rate of the primary tumor does not directly parallel metastatic ability, and that the tumors grow faster in younger women.

Age Factors↗
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High 10-year survival rate in patients with early, untreated prostatic cancer.

OBJECTIVE: To learn about the natural history of untreated, early-stage prostatic cancer. DESIGN: Cohort study with a mean follow-up of 123 months (range, 81 to 165 months). SETTING: Population-based, regionally well defined. PATIENTS: A consecutive sample of 223 patients (98% of all eligible) with early-stage (T0-2, NX, M0), initially untreated prostatic cancer. MAIN OUTCOME MEASURES: Progression-free, disease-specific, and overall survival. Need for palliative and terminal care. INTERVENTION: Patients with tumor progression were hormonally treated (orchiectomy or estrogens) if they had symptoms. RESULTS: After complete follow-up, only 19 (8.5%) of the 223 patients had died of prostate cancer and 105 (85%) of a total of 124 deaths were from other causes. The 10-year, disease-specific survival rate was 86.8% (95% confidence interval, 80.7% to 92.9%) and was equally high (87.9%) in a subgroup of 58 patients who met current indications for radical prostatectomy. The progression-free, 10-year survival rate was 53.1% (95% confidence interval, 44.2% to 62.0%). In 50 of 76 patients, local growth provided the only evidence of progression, and endocrine treatment was generally successful in these cases. Following an initial increase, the rate of disease progression and death from prostate cancer decreased during the last years of follow-up. CONCLUSION: The low disease-specific mortality rate, especially in patients with highly and moderately differentiated tumors, means that any local or systemic therapy intended for patients with early prostatic cancer must be evaluated in clinical trials with untreated controls for comparison.

Aged↗
PubMedDate not supplied

Transamidating enzymes in maternal plasma and placenta in human pregnancies complicated by intrauterine growth retardation.

Transamidases are enzymes, which are necessary for normal clot formation. They fall into two types: thrombin-dependent Factor XIII and thrombin-independent tissue transglutaminases. The investigation showed that human placenta contains not only Factor XIII, but also considerable amounts of a tissue trans-glutaminase identical with an enzyme present in red blood cells. A quantitative assay for transamidases, using incorporation of radioactively labelled putrescine into casein, was applied to placental extracts. With this assay the amounts of thrombin-dependent and thrombin-independent transamidases were determined in the placenta of fullterm infants and term infants who were small for gestational age. The transamidase activities of the placenta in the two groups showed no statistically significant difference. Plasma Factor XIII subunit a antigen concentration was increased by about 40% in midpregnancy and returned to normal nonpregnant values in the 3rd trimester, but when intrauterine growth was retarded the plasma Factor XIII concentration remained elevated. Plasma Factor XIII activities showed a similar variation.

Factor XIII↗