PubMed Health⌕ Search

Biomedical subjects

M C Sunderland

Publications and source records attributed to M C Sunderland.

7 recordsLinked to original sources

Failure of GM-CSF to permit dose-escalation in an every other week dose-intensive regimen for advanced breast cancer.

BACKGROUND: In an attempt to improve dose intensity and therapeutic effectiveness in breast cancer, GM-CSF was incorporated into a multi-drug every other week chemotherapy regimen that had been previously reported to have promising activity, but whose dose-limiting toxicity was neutropenia. PATIENTS AND METHODS: A Phase I-II study in patients with locally advanced or metastatic breast cancer was initiated using GM-CSF and a 5-drug chemotherapy regimen employing oral cyclophosphamide daily for 7 days and doxorubicin, vincristine, methotrexate, 5-fluorouracil, and leucovorin IV every 2 weeks for 10 courses. In the first 8 patients, GM-CSF in escalating doses (1-20 micrograms/kg s.c. per day) was given on days 8-13 of each 2 week cycle. In the last 12 patients, GM-CSF was given on days 3-14 of each cycle in an attempt to improve its effectiveness by prolonging treatment duration. RESULTS: The regimen was poorly tolerated. Only 10 patients completed all 10 courses of treatment, and most of those required dose delays and/or reductions. GM-CSF failed to reduce neutropenia when given by either schedule. Furthermore, thrombocytopenia was severe and progressive, especially with the more prolonged GM-CSF schedule in which the mean lowest nadir platelet count was 15,000/microliters. Anemia, fatigue, mucositis, and neutropenic fevers were also common, and dose escalations were not possible in any patient. Central venous catheter complications were also common. Complete or partial remissions were observed in 15 of 20 patients, but response durations were brief. CONCLUSIONS: GM-CSF in two different schedules failed to ameliorate myelosuppression when used in combination with this multiple drug, every other week regimen. Neutropenia and, especially, thrombocytopenia remained dose limiting.

Adult↗

Interleukin-3. Its biology and potential uses in pediatric hematology/oncology.

The hematopoietic growth factor interleukin (IL)-3 is a potent regulator of blood cell proliferation. It promotes the survival, proliferation, and development of hematopoietic stem cells and committed progenitor cells of the granulocyte-macrophage, erythrocyte, eosinophil, basophil, megakaryocyte, mast cell, and lymphocyte lineages. In addition, IL-3 enhances mature myeloid cell functions such as phagocytosis and activation of basophils and eosinophils, as well as monocyte cytotoxicity. The first phase of clinical trials suggested that IL-3 may augment myelopoiesis in a number of clinical conditions. It may be efficacious for treatment of primary marrow disorders, including myelodysplastic syndromes and aplastic anemia. However, replacement therapy with IL-3 alone is probably not sufficient to obtain maximal stimulation of myelopoiesis. Preclinical and clinical studies published to date suggest that sequential use or combinations of growth factors will be needed to obtain optimal hematopoietic responses.

Animals↗

Tamoxifen in premenopausal patients with metastatic breast cancer: a review.

The antiestrogen tamoxifen is the most widely used hormonal therapy for breast cancer. The drug exerts its antiproliferative effects primarily through estrogen receptor (ER)-mediated mechanisms, although other cellular actions may augment tumor inhibition. Clinically, tamoxifen has been less well studied in premenopausal than in postmenopausal patients. The drug has complex endocrine effects that are dependent on the treatment duration and dose, menopausal status, and target organ. In postmenopausal women receiving tamoxifen, serum estrogen levels remain low, and the normally elevated gonadotropin levels decrease. In contrast, serum estrogen levels are strikingly elevated in many premenopausal women, and gonadotropin concentrations are either unchanged or slightly increased. Large systematic trials in metastatic breast cancer have established tamoxifen as the recommended hormonal therapy for postmenopausal women with ER-positive tumors. Tamoxifen is also an active agent for premenopausal metastatic disease, and response rates are comparable to those reported for oophorectomy. Clinical experience with tamoxifen in this younger age group, however, is more limited. Few premenopausal women (less than 400) have been included in phase II and phase III trials. Two randomized trials (total of 160 patients) comparing oophorectomy with tamoxifen do not definitively establish therapeutic equivalence, and a survival advantage for either treatment cannot be excluded. Many questions remain concerning the appropriate role for tamoxifen in premenopausal patients. Still, tamoxifen has an attractive toxicity profile, and it offers a favorable therapeutic alternative for premenopausal women with ER-positive metastatic breast cancer who wish to avoid surgical or radiation castration.

Breast Neoplasms↗

Prognostic indicators in invasive breast cancer.

Tumor size and axillary lymph node involvement are the primary determinants of clinical course for most patients. Receptors for estrogen and progesterone are important additional prognostic factors for disease-free survival, overall survival, survival time after initial disease recurrence, and the likelihood of response to hormonal therapy. Histologic grading has merit as a prognostic factor, although poor reproducibility limits its broad application. Promising data have been emerging from the use of flow cytometry to analyze DNA content and proliferative rate. Patients with aneuploid tumors are more likely to have a shorter survival time than patients with diploid tumors. A high S-phase fraction also identifies a subset of patients at increased risk for early relapse. A combined index of ploidy and S-phase may be a more useful guide; together, diploidy and low S-phase identify a subgroup of node-negative patients at very low risk for disease recurrence. A number of oncogenes have been identified in breast cancer; amplification of the HER-2/neu gene or overexpression of the gene product may be an important prognostic indicator for node-positive patients.

Breast Neoplasms↗

Serum gamma-glutamyl transpeptidase activity in patients receiving chronic phenytoin therapy.

To better define the incidence and range of elevated gamma-glutamyl transpeptidase (GGT) activity in patients taking a drug known to induce hepatic microsomal enzymes, GGT was measured in the sera of 58 patients before and after six months of phenytoin therapy. Enzyme activity at six months was greater than baseline in 52 of 58 patients (90%). GGT activity (normal, 0-50 units/liter) was 45.2 +/- 9.9 (mean +/- SEM) at baseline and 135.8 +/- 18.1 after six months of therapy, a mean threefold increase (P less than 0.001). Of the 45 patients with normal baseline GGT activity, some had marked elevation of serum GGT activity with values rising over 200 units/liter in eight patients and over 300 units/liter in four patients. Mean serum GGT activity remained significantly elevated at 12 and 24 months. This elevation in GGT activity was not influenced by age, sex, or additional anticonvulsant drug therapy. Both baseline and six-month GGT activity was lowest in patients who drank no alcohol, higher in patients who drank 0-1 pint/week, and greatest in patients who drank greater than 1 pint/week. All 13 patients with elevated baseline GGT activity were regular users of alcohol and/or taking other enzyme-inducing drugs. In conclusion, increase in serum GGT activity occurs in 90% of patients on long-term phenytoin therapy, most often to moderate but occasionally to high levels, and this rise in GGT activity is accentuated by regular consumption of alcohol.

Adult↗