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Biomedical subjects

W S Fletcher

Publications and source records attributed to W S Fletcher.

At least 37 records · Page 2Linked to original sources
PubMed1994

Results of cisplatin hyperthermic isolation perfusion for stage IIIA and IIIAB extremity melanoma.

Between 1983 and 1992, 21 patients with extremity stage IIIA or IIIAB melanoma underwent hyperthermic isolation limb perfusion (HILP) with cisplatin in dosages varying from 26 to 237 mg/m2 as part of a pharmacokinetics and maximum-tolerated dose study. Extremity temperatures were up to 40 degrees C and the pH was controlled near 7.4. There were no major complications in this series of patients. Overall survival was 55% at 2 years and 47% at 5 years. Local control rates excluding regional nodal control was 79% at 2 years and 53% at 5 years. Local control, including regional nodal control, was 61% at 2 years and 36% at 5 years, indicating that cisplatin is not as effective at nodal control as it is at control of dermal or subcutaneous metastases. Three patients who failed cisplatin HILP have responded to re-perfusion with melphalan and actinomycin D. Two of the three patients had complete responses. It is concluded that cisplatin is an active agent against melanoma when employed by HILP. The drug is well tolerated at the doses and temperature employed, but it is not superior to HILP with melphalan.

Adult↗
PubMed1994

Didemnin B in metastatic malignant melanoma: a phase II trial of the Southwest Oncology Group.

Didemnin B is a cyclic peptide isolated from the marine tunicate Trididemnin cyanophorum. It is a known potent inhibitor of RNA, DNA and protein synthesis, with activity against the murine B16 melanoma. Fourteen patients with disseminated malignant melanoma were evaluated in a Southwest Oncology Group phase II trial of didemnin B at 4.2 mg/m2 by 30 min i.v. infusion every 28 days (SWOG-8754). Only patients with no prior chemotherapy were eligible; prior radiation therapy, surgery and at most one prior biologic regimen were allowed. Patients with brain metastasis were eligible only if the disease in the brain had been treated and controlled. All patients had to have normal renal and hepatic function and adequate granulocyte and platelet counts, a performance status of 0-2, and bidimensionally measurable disease. Fourteen patients were entered on the study; five received one and nine received two courses of didemnin B. No responses were noted among the 11 patients evaluable for response. Five patients developed unusual but reversible hypersensitivity reactions during the second course of therapy. Other toxicity in this trial was nausea and vomiting and diarrhea, none of severity greater than grade 3. Given the lack of antitumor efficacy and the unusual toxicity, further evaluation of didemnin B in this dose and schedule in malignant melanoma is not warranted.

Adult↗
PubMed1993

Cyclophosphamide, methotrexate, and 5-fluorouracil in the treatment of metastatic prostate cancer. A Southwest Oncology Group study.

BACKGROUND: Hormone-refractory metastatic prostate cancer remains a therapeutic challenge. Cyclophosphamide, methotrexate, and 5-fluorouracil (CMF), a drug combination that is active in solid tumors, was evaluated using specific response criteria. METHODS: Fifty-two eligible patients with measurable (19), evaluable (29), or bone scan only (4) metastatic prostate cancer were treated with cyclophosphamide, 100 mg/m2 every day by mouth, methotrexate, 15 mg/m2 intravenously weekly, and 5-fluorouracil, 300 mg/m2 intravenously weekly. Treatment was given continuously unless interrupted by toxicity or disease progression. RESULTS: There were two partial responses (7%) among the evaluable patients. Six (32%) measurable patients and four (14%) evaluable patients had stable disease. Median time to progression was 3.2 months for measurable and 2.8 months for evaluable disease patients. Median survivals were 10.9 and 10.2 months, respectively. There was no difference between the two groups with regard to response rate or survival. Toxicity was acceptable and consisted primarily of myelosuppression. CONCLUSIONS: CMF is minimally active in hormone-refractory metastatic prostate cancer.

Acid Phosphatase↗
PubMed1993

Inhibition of angiogenesis by somatostatin and somatostatin-like compounds is structurally dependent.

We have previously demonstrated that somatostatin analogues SMS 201-995 and RC-160 inhibit angiogenesis using the chorioallantoic membrane (CAM) of the developing chicken embryo. In this study, we evaluated the ability of native somatostatin 14 and nine somatostatin analogues to inhibit angiogenesis. Two-millimeter methylcellulose disks containing 50 micrograms of somatostatin or somatostatin analogue were implanted on the CAM of 6- to 7-day-old shell-less chick embryos. Inhibition of blood vessel growth was visually assessed and graded in the region of the disk 24-36 hr following implementation. The analogues SMS 201-995 and RC-160 showed statistically significant inhibition of neovascularization when compared to native somatostatin 14. The amino acid homology comparison of the nine analogues revealed that individual differences in their abilities to inhibit angiogenesis may be structurally dependent.

Animals↗
PubMed1993

Evaluation of cisplatin and DTIC in inoperable stage III and IV melanoma. A Southwest Oncology Group study.

The Southwest Oncology Group entered 62 patients with Stage IV or inoperable Stage III (one patient) melanoma into SWOG protocol 8804 and treated them with cisplatin 100 mg/m2 and DTIC 750 mg/m2 i.v. infusion over 15-30 minutes. There were 18 patients with brain metastases and four ocular primaries. Five patients, all without bain metastases, were ineligible. Responses of 8 patients could not be determined, and 11 patients received only one course of treatment. Of the eligible patients, 46 (81%) had some hematologic toxicities, with 31 of these (67%) having grade III or worse. There were 23 patients (40%) with renal toxicities. The miscellaneous toxicities were muscle weakness, flu-like symptoms, and fatigue. Five patients died while on treatment. There were no complete responses. Eight patients had partial responses ranging from 1.5 to 10.5 months, although two patients were still alive at 30.4 and 30.9 months. The estimated response rate for patients with brain metastases was 11%. The estimated response rate for patients without brain metastases was 13%. If one unconfirmed partial response is included, the overall response rate is 14% with a 95% confidence interval of 6% to 26%. It is concluded that DTIC and cisplatin have definite activity in melanoma, but, at least in this population, the toxicity is treatment-limiting and requires close attention to patient care.

Adult↗
PubMed1992

Effective palliative treatment of metastatic carcinoid tumors with intra-arterial chemotherapy/chemoembolization combined with octreotide acetate.

Survival in patients with metastatic carcinoid tumors is dependent on control of tumor growth and adequate palliation of vasoactive amine-induced symptoms of flushing, diarrhea, wheezing, and valvular heart disease. Eight patients with carcinoid tumors metastatic to the liver were treated with long-term octreotide acetate therapy (100 to 500 micrograms three times a day), intra-arterial 5-fluorouracil infusion (2 g/day x 5 days), and hepatic tumor chemoembolization. All eight patients became asymptomatic and have remained so with a mean follow-up duration of 22 months from the time of first infusion. Following institution of subcutaneous octreotide acetate, intra-arterial infusion, and tumor chemoembolization, all patients are alive with a mean survival of 40 months from the time of diagnosis of carcinoid syndrome (range: 2 to 108 months). Four patients had greater than a 50% decrease in tumor size after therapy (mean follow-up duration: 10.6 months), and the other four patients have had stable disease after institution of therapy. It appears that combinations of long-term subcutaneous administration of octreotide acetate, intra-arterial 5-fluorouracil, and tumor chemoembolization effectively control progressive liver metastasis and provide excellent symptomatic palliation in patients with hepatic metastasis from functional carcinoid tumors.

Carcinoid Tumor↗
PubMed1992

Synergistic cytotoxicity of combinations of dimethyl sulfoxide and antineoplastic agents against P388 leukemia in CD-F1 mice.

We have reported that dimethyl sulfoxide (DMSO) and antineoplastic agents exhibit synergistic cytotoxicity against human tumors in vitro. This study was undertaken to investigate this effect in vivo. Groups of mice were given intraperitoneal (i.p.) injections of P388 leukemia cells. Groups were treated with i.p. injections of either saline, DMSO alone, mitoxantrone hydrochloride (DHAD) alone, methotrexate alone, DHAD in DMSO or methotrexate in DMSO. Combinations of DMSO and DHAD produced 46-61% increases above expected survival, demonstrating synergistic cytotoxicity in vivo. Following confirmatory animal studies, trials utilizing i.p. delivery of antineoplastics in DMSO as treatment for peritoneal tumors should be undertaken.

Animals↗
PubMed1991

Phase III comparison of doxorubicin and dacarbazine given by bolus versus infusion in patients with soft-tissue sarcomas: a Southwest Oncology Group study.

Disseminated soft-tissue sarcomas are a group of uncommon malignancies generally treated in a uniform manner. This study questioned the impact of schedule on response rate and toxicity in patients with metastatic soft-tissue sarcoma treated with the two-drug combination doxorubicin and dacarbazine. Patients were randomly assigned to receive either bolus therapy with doxorubicin at a dose of 60 mg/m2 and dacarbazine at a dose of 750 mg/m2 intravenously on day 1 (118 patients) or infusional therapy with doxorubicin at 60 mg/m2 and dacarbazine at 750 mg/m2 delivered by continuous intravenous infusion for 96 hours on days 1-4 (122 patients). Chemotherapy was to be repeated every 3 weeks. A unique feature of this cooperative group protocol was a provision for surgical resection of residual disease in patients with a partial response or with stable disease following chemotherapy. Similar overall response rates (17% in both treatment arms) and complete response rates (5% in both treatment arms) were observed. For patients receiving bolus therapy, the median response duration was 19.6 months for those in complete remission and 6.6 months for those in partial remission. For patients receiving infusional therapy, the median response duration was 12.6 months for those in complete remission and 9.3 months for those in partial remission. Examination of dose intensity received when combining treatment arms revealed a weak doxorubicin dose-response relationship. There was no difference in median survival times between the two treatment arms (bolus therapy, 10.6 months; infusional therapy, 10.5 months; logrank P = .97). Analysis of toxic effects favored infusional therapy. Significant reductions in cardiac toxicity (all events, P = .04; clinical events, P = .01) and nausea and emesis (P = .04) were seen in infusional therapy. Of 47 patients eligible for cytoreductive surgery following chemotherapy, 12 received surgery, and of those 12, eight were rendered disease free. The use of a 96-hour continuous intravenous infusion of doxorubicin-dacarbazine was comparable therapeutically with bolus dosing of these two agents and was better tolerated by the patients.

Adolescent↗
PubMed1990

High-dose cisplatin for metastatic soft tissue sarcoma.

Between August 1984 and January 1987, the Southwest Oncology Group (SWOG) registered 46 patients with metastatic sarcomas on SWOG 8465, a Phase II trial of high-dose cisplatin in patients with metastatic soft tissue sarcoma. Six patients were ineligible for the following reasons: poor performance status (two patients); ineligible diagnosis (three patients, two with Ewing's sarcoma of bone and one with metastatic chondrosarcoma); and evaluable but nonmeasurable disease (one patient with bone-only disease). Of the 40 fully evaluable patients, 34 had received prior chemotherapy; treatment was with cisplatin (40 mg/m2/d for 5 consecutive days). Cisplatin was mixed in 250 ml of 3% NaCl and hydrated with a normal saline solution at a rate of 250 ml/h, beginning 12 hours before the first dose of cisplatin was specified. The second treatment was given 3 weeks after the first, with all subsequent treatments given every 4 weeks. After three cycles of treatment, responding patients were treated at a cisplatin dose of 20 mg/m2/d for 5 consecutive days. Leukopenia was of Grade 3 or 4 in seven patients, whereas thrombopenia was of Grade 3 or 4 in eight patients. More severe myelosuppression was produced in patients who had received prior radiotherapy. A single case of reversible Grade 4 nephrotoxicity was produced; neurotoxicity was observed in 11 cases, but was of Grade 3 in only 2 cases. Of the 40 evaluable cases, six showed partial responses or no responses, for a major response rate of 15%. High-dose cisplatin has minor activity and major toxicity in the treatment of metastatic soft tissue sarcomas, and should be considered investigational.

Adult↗
PubMed1990

Treatment of nonendocrine gastrointestinal disorders with octreotide acetate.

Somatostatin and its longer-acting analog, octreotide acetate, can be used effectively for the treatment of nonendocrine gastrointestinal disorders. Octreotide has been shown to decrease pancreatic fistula output by suppressing exocrine pancreatic function. We believe that octreotide acetate may be useful to prophylaxis against the development of pancreatic fistulas following pancreatic resection and may reduce the enzymatic and volume output of established pancreatic fistulas. We also have shown that administration of octreotide acetate 2 hours before a high carbohydrate test meal reduces gut peptide levels, which increase following meal ingestion in patients with the dumping syndrome. Reduction of circulating peptides in these patients may slow gut motility and improve glucose regulation, thus, providing relief of postvagotomy dumping symptoms.

Dumping Syndrome↗
PubMed1990

Effect of somatostatin analog on peptide release and tumor growth in the Zollinger-Ellison syndrome.

The clinical presentation of Zollinger-Ellison syndrome (ZES) is the result of gastrin hypersecretion and may be modified by secondary peptide hypersecretion. Treatment is medical (H2-blockers) or surgical (tumor excision and total gastrectomy). H2-blocker escape occurs up to 23 per cent and surgical mortality ranges to 15 per cent. Treatment of advanced disease has limited success. Sandostatin (SMS 201-995) has been shown to decrease basal gastrin and gastric acid secretion in ZES. We hypothesized that SMS would suppress basal and provoked gastrin and secondary peptide secretion in ZES. A patient with refractory, metastatic gastrinoma underwent provocative testing (test meal, calcium infusion, secretion bolus and tolbutamide bolus). Thirteen peptides were drawn at set intervals during these provocative tests. Testing was repeated during SMS therapy (100 micrograms subcutaneously three times per day). Gastrin, pancreatic polypeptide (PP) and glucagon levels were elevated at baseline. SMS suppressed all three peptides (mean 74 per cent) (p less than 0.05). Gastrin, PP and glucagon were provoked by all four tests (means above baseline, 19, 155 and 138 per cent, respectively). Gastrin-releasing peptide, gastric inhibitory peptide and insulin were provoked by calcium infusion (427, 306 and 162 per cent above baseline, respectively). SMS suppressed 14 of 15 of these peaked-provoked peptide levels (mean 72.5 per cent, p less than 0.05). Gastric analysis during calcium infusion showed SMS suppression of hourly gastric secretory volume by 77.5 per cent and of acid production (milliequivalents of acid) by 87.5 per cent. During a 20 month follow-up period, the patient was maintained on SMS, 200 micrograms subcutaneously three times per day. She has remained asymptomatic. Interval peptide profiles at two, eight and 18 months show normal gastrin, PP and glucagon levels. A computed tomographic scan at eight months shows a remarkable regression of primary and metastatic tumor. Regrowth, however, was noted at 19 months. SMS may be useful in ZES by suppressing basal and provoked gastrin and secondary peptide secretion and may occasionally give palliation by yielding temporary tumor registration.

Aged↗
PubMed1990

Adult onset nesidioblastosis: response of glucose, insulin, and secondary peptides to therapy with Sandostatin.

Adult onset nesidioblastosis (AON) is an extremely rare entity associated with hypersecretion of insulin. Previous reports have demonstrated that the somatostatin analog, Sandostatin (SMS), will control the clinical symptoms induced by infantile nesidioblastosis. We hypothesized that insulin, C-peptide, and secondary peptide secretion from AON is provocable. We also hypothesized that SMS would suppress both basal and provoked primary and secondary peptide secretion in AON. To test this hypothesis, in a patient with AON, 13 gut peptide levels were determined at set intervals during provocative testing with a test meal, a calcium infusion, a secretin bolus, and a glucagon bolus. These tests were repeated under the influence of SMS. Insulin, C-peptide, and pancreatic polypeptide (PP) levels were elevated in the basal state. SMS suppressed all three peptides (mean 68%) (p less than 0.05). Basal fasting glucose rose by 65%, and glucose ratios were raised throughout all four tests. Insulin:glucose ratios decreased during SMS therapy. Insulin and PP secretion was increased by all four provocative tests (mean 458% and 665% above baseline, respectively). C-peptide was provoked by three tests (mean 204%). Peptides with normal basal values were also provocable. GRP and glucagon were provoked by secretin stimulation (182%, 186%, respectively). Calcium infusion stimulated CIP release by 372%. SMS suppressed the peak provoked peptide levels in all positive provocation tests (p less than 0.05). Peak provoked insulin values were decreased by 59%, C-peptide by 75%, and PP by 92%. Peak provoked glucagon, CRP, neurotensin, and GIP levels were decreased by 20%, 65%, 51%, and 73%, respectively. The patient has been maintained on SMS (25 micrograms bid) for 1 yr and has shown decreased insulin levels, normal glucose levels, and, at 1 yr, leads an asymptomatic normal life. SMS is able to suppress primary and secondary peptide secretion in both the fasting and provoked state. The long-term efficacy of SMS may be predicted by its ability to suppress primary peptide release during peak provocation.

Aged↗
PubMed1989

Long-term results with primary retroperitoneal tumors.

Primary retroperitoneal tumors represent a variety of lesions, with different treatments and prognoses. Of 182 patients in our study, retroperitoneal tumor was recognized preoperatively in only 39% of them. Sarcomas were most common (43% of patients), followed by lymphomas (23%), benign tumors (11%), undifferentiated malignant tumors (11%), carcinomas (8%), and germ cell tumors (4%). In 81 patients since 1960, the resection rate was 50%. Operative determinants of resectability were pathologic category and grade and extent of tumor. Resection included segments of the gastrointestinal tract (30% of the patients), kidney (25%), and pancreas, bladder, spleen, aorta, and vena cava (for each, 5% or less of the patients). The operative mortality was 6%. Tumor caused late death in 95% of the patients. Pathologic findings were a significant determinant of survival in the 81 patients. For sarcomas, 69% of the patients underwent resection, and the 1- and 5-year actuarial survival rates were 80% and 43%, respectively. Sixty percent of these patients underwent multiple operations. For lymphomas, most patients were treated with radiotherapy and chemotherapy; the 1- and 5-year survival rates were 67% and 35%, respectively. Benign tumors, almost all resected, yielded a 5-year survival rate of 100%. Undifferentiated tumors and carcinomas, most treated with radiotherapy and chemotherapy, had a 1-year survival rate of less than 33%. Other determinants of survival were age, weight loss, grade of tumor, and extent of tumor. Patients who underwent palliative resection had the same survival rate as patients who underwent biopsy alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗