Biomedical subjects

Gilberto Schwartsmann

Publications and source records attributed to Gilberto Schwartsmann.

39 records · Page 3Linked to original sources

PubMed2002

Clinical and pharmacokinetic study of fractionated doses of oral etoposide in pediatric patients with advanced malignancies.

BACKGROUND: The purpose of this phase I study was to evaluate the toxicity profile, dose-limiting toxicities (DLT), maximum tolerated dose (MTD), and plasma pharmacokinetics of oral etoposide, and to recommend a safe fractionated dose for phase II trials in pediatric patients with refractory solid tumors. MATERIAL/METHODS: All patients had tumors no longer amenable to established forms of treatment. The initial dose of etoposide was 20 mg/m(2) TID for 14 days every 21 days (dose-level I). Etoposide plasma pharmacokinetics were studied on day 1 of treatment and determined by HPLC. RESULTS: Seventeen children were enrolled, 13 of whom were included in the pharmacokinetic study, for a total of 64 courses. Nine patients were included at dose-level I; grade 2-3 leucopenia was observed in 5. The dose was then raised to 25 mg/m(2) (dose-level II) in another 8 patients; grade 3-4 leucopenia was observed in 4. This dose-level was therefore considered the MTD. The DLT was neutropenia. In patients at dose-level I and II the maximum plasma etoposide concentration was 2.97 and 8.59 mg/ml, respectively. Drug levels > 1 microg/ml were maintained for about 6.3 hours following drug administration at both dose-levels. Partial response was observed in 1 patient and 4 patients showed stable disease. CONCLUSIONS: Prolonged oral etoposide was well tolerated by our patients. Considering the MTD, and the fact that the patients included at dose-level I achieved an adequate (>1 microg/ml) plasma concentration of etoposide for a sufficient time, this dose level was recommended for phase II studies in pediatric malignancies.

Administration, Oral↗

PubMedDate not supplied

Overview of breast health care guidelines for countries with limited resources.

Among women around the globe, breast cancer is both the most common cancer and the leading cause of cancer-related death. Women in economically disadvantaged countries have a lower incidence of breast cancer, but poorer survival rates for the disease relative to women in affluent countries. Evidence suggests that breast cancer mortality can be reduced if resources are applied to the problem in a systematic way. The purpose of the Global Summit Consensus Conference was to begin a process to develop guidelines for improving breast health care in countries with limited resources-those with either low- or medium-level resources based on World Health Organization (WHO) criteria. Breast cancer experts and patient advocates representing 17 countries and 9 world regions participated in the conference. They reviewed the existing breast health guidelines, which generally assume unlimited resources. Individual panels then discussed and debated how limited resources can best be applied to improve three areas of breast health care--early detection, diagnosis, and treatment--and how to integrate these areas in building a breast health care program. The panelists unanimously agreed on the guiding principle that all women have the right to access to health care. They also agreed that collecting data on breast cancer is imperative for deciding how best to apply resources and for measuring progress. The panelists acknowledged the considerable challenges in implementing breast health care programs when resources are limited, as well as the need to build a program that is specific to each country's unique situation. The panelists noted that the development of centralized, specialized cancer centers may be a cost-effective way to deliver breast cancer care to some women when it is not possible to deliver such care to women nationwide. In countries with limited resources, at least half of the women have advanced or metastatic breast cancer at the time of diagnosis. Because advanced breast cancer has the poorest survival rate and is the most resource intensive to treat, measures to reduce the stage at diagnosis are likely to have the greatest overall benefit in terms of both survival and costs. Women should have access to diagnosis and treatment if efforts are undertaken to improve early detection of breast cancer. The panels' findings outline specific steps for prioritizing the use of limited resources to decrease the impact of breast cancer around the globe.

Breast Neoplasms↗

PubMedDate not supplied

Treatment of breast cancer in countries with limited resources.

Early and accurate diagnosis of breast cancer is important for optimizing treatment. Local treatment of early stage breast cancer involves either mastectomy or breast-conserving surgery followed by whole-breast irradiation. The pathologic and biologic properties of a woman's breast cancer may be used to estimate her probability for recurrence of and death from breast cancer, as well as the magnitude of benefit she is likely to receive from adjuvant endocrine therapy or cytotoxic chemotherapy. Ovarian ablation or suppression with or without tamoxifen is an effective endocrine therapy in the adjuvant treatment of breast cancer in premenopausal women with estrogen receptor (ER)-positive or ER-unknown breast cancer. In postmenopausal women with ER- and/or progesterone receptor (PR)-positive or PR-unknown breast cancer, the use of tamoxifen or anastrozole is effective adjuvant endocrine therapy. The benefit of tamoxifen is additive to that of chemotherapy. Cytotoxic chemotherapy also improves recurrence rates and survival, with the magnitude of benefit decreasing with increasing age. Substantial support systems are required to optimally and safely use breast-conserving approaches to local therapy or cytotoxic chemotherapy as systemic therapy. Locally advanced breast cancer (LABC) accounts for at least half of all breast cancers in countries with limited resources and has a poor prognosis. Initial treatment of LABC with anthracycline-based chemotherapy is standard and effective. Addition of a sequential, neoadjuvant taxane thereafter increases the rate of pathologic complete responses. Neoadjuvant endocrine therapy may benefit postmenopausal women with hormone receptor-positive LABC. After an initial response to neoadjuvant chemotherapy, the use of local-regional surgery is appropriate. Most women will require a radical or modified radical mastectomy. In those women in whom mastectomy is not possible after neoadjuvant chemotherapy, the use of whole-breast and regional lymph node irradiation alone is appropriate. In those women who cannot receive neoadjuvant chemotherapy because of resource constraints, mastectomy with node dissection, when feasible, may still be considered in an attempt to achieve local-regional control. After local-regional therapy, most women should receive additional systemic chemotherapy. Women with LABC that has a positive or unknown hormone receptor status benefit from endocrine therapy with tamoxifen. The treatment of LABC requires multiple disciplines and is resource intensive. Efforts to reduce the number of breast cancers diagnosed at an advanced stage thus have the potential to improve rates of survival while decreasing the use of limited resources.

Antibiotics, Antineoplastic↗