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PubMed1986

Medicare payment for new technologies. Can the process be improved despite conflicting goals? An ECRI technology management assessment.

Decisions about Medicare payment for new technologies are made by a multiagency process that became even more complex with the advent of DRG-based payments for inpatient care. Numerous problems with this decision-making process are widely acknowledged to exist but difficult to solve because of inherent conflicting goals. This report proposes consideration of basic improvements to the process, including: increased support for clinical and cost studies, particularly from manufacturers of new technologies; approval of provisional payments to providers who agree to collect effectiveness and cost data; additional research into technology assessment methods; clarification of decision-making criteria; opening of the coverage-decision process to greater public scrutiny; according more weight to recommendations of the Prospective Payment Assessment Commission; submission of additional data to the Food and Drug Administration; and increasing the flow of information among Medicare coverage-decision agencies and other third-party payers. Many of these modifications can be accomplished without congressional action, if the interested parties are willing to work together to improve the coverage-decision process.

Centers for Medicare and Medicaid Services, U.S.↗

PubMed2001

Neuroblastoma.

OBJECTIVE: Due to the poor results achieved on combination chemotherapy and the unproven cost-effectiveness value of myeloablative therapy, the question has been raised; should patients with stage IV neuroblastoma be actively treated? The aim of the current study is to analyze retrospectively treatment results of 43 children with neuroblastoma with special stress on the rate and duration of remission in children with disseminated neuroblastoma. METHODS: Treatment of children with neuroblastoma consisted of surgical removal of the tumor, if possible, followed by chemotherapy for unresectable residual tumor including metastases. Second look surgery was performed to resect residual masses rendered resectable on chemotherapy in the absence of distal metastases. The chemotherapy protocol used in the current study consisted of alternating combination chemotherapy regimens containing, Cyclophosphamide, Vincristine and Doxorubicin, alternating with Cis-platinum and Etoposide. RESULTS: The male to female ratio was 2:1 with a median age of 2.1 years. The abdomen was the primary site of involvement encountered in 32 patients (74%). According to the childrens cancer study group (CCSG) staging system, only 6 patients (14%) had localized tumors (stages I and II). Two patients (5%) were found to have stage IV. Stage III was documented in 5 patients (12%). The majority of patients (70%) had disseminated disease at presentation. The bone marrow was the most common site of metastatic deposit, encountered in 23 patients out of the 30 with stage IV disease (77%). Out of the 12 evaluable non-stage IV patients, only one patient (8%) showed treatment failure. Assessment of response by the end of the 6th month from the date of diagnosis revealed that out of the 27 evaluable patients with stage IV, 4 patients achieved complete remission, 7 patients achieved very good partial remission, 8 patients achieved partial remission and 4 patients achieved mixed response. Three patients showed progressive disease on chemotherapy. Twenty-one patients (78%) were symptom-free and were conducting normal life. Assessment of response to treatment by the end of the 12th month from diagnosis revealed that 6 patients (2 complete remissions, 1 very good partial response, 3 partial responses) were maintaining their remission. Out of the 19 patients showing complete or partial remission at early assessment, 4 patients maintained their remission for more than 18 months. Two (one was in complete remission and the other was in partial response) of them progressed in areas of previous involvement after 20 and 21 months. The other 2 patients (one was in complete remission and the other was in partial response) showed disease progression in areas not previously affected by disease at presentation after 23 and 42 months. CONCLUSION: Results of treatment by multiagent chemotherapy regimens used in the current study show that children with neuroblastoma, even those with advanced stages, should receive the benefit of intensive multimodal therapy, even those with partial response to initial therapy. These patients may experience reasonable symptom-free and sometimes, disease-free survival.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1989

A phase I-II trial of cisplatin, hyperthermia and radiation in patients with locally advanced malignancies.

A Phase I-II trial testing the addition of systemic cisplatin (CDDP) to local hyperthermia and radiation was conducted to determine the dose of cisplatin that is tolerable once weekly for 6 weeks and to estimate the therapeutic potential of this trimodality combination in patients with locally advanced malignancies. Cisplatin at 20 mg/m2 (4 patients), 30 mg/m2 (8 patients), and 40 mg/m2 (12 patients) was given rapidly (over 5-10 min) i.v. after prehydration with 1 liter of normal saline. After approximately two-thirds of the cisplatin dose had been delivered, microwave hyperthermia was begun and continued for 60 min; the target minimum tumor temperature was 43 degrees C. Following hyperthermia, a 400 cGy fraction of radiation was delivered to the tumor. On other days during the treatment weeks, additional 200 cGy fractions were given to total doses of 6,000-6600 cGy in patients with full radiation tolerance or 2400-3600 cGy in patients with limited radiation tolerance. The 24 patients in this trial had a median age of 57 years and the predominant sites/tumor types were head and neck/squamous cell carcinoma (9) and chest wall/breast adenocarcinoma (9). Seventeen of the 24 treated tumors (70%) had previously been irradiated. Eighteen patients (75%) had received prior chemotherapy and nine patients (38%) had previously been treated with cisplatin. Bone marrow suppression was dose limiting in patients heavily pretreated with chemotherapy and chest wall radiation. No significant toxicities were observed at the 20 and 30 mg/m2 dose levels, but 5 of the 12 patients (42%) treated at 40 mg/m2 required modification of the cisplatin dose because of blood count suppression in four patients and mild renal dysfunction in one patient. Each of the patients with bone marrow suppression, however, had been heavily pretreated except for one patient with thrombocytopenia due to hypersplenism. Nausea and vomiting were mild with use of a standard, multiagent antiemetic regimen. Twelve patients (50%) attained a complete regression (CR) and 12 patients (50%) a partial regression (PR). Complete regression appeared to correlate with small tumor volumes (115 cc for CR versus 199 cc for PR patients) and higher tumor temperatures (4.6 average minimum equivalent minutes at 43 degrees C in CR versus 2.0 min in PR patients). Local toxicities included second degree burns in 12 patients (50%) and third degree burns in 6 (25%), but all burns healed in 4-12 weeks without surgical intervention.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1983

Lack of potentiation of vincristine-induced neurotoxicity by VP-16-213.

Due to a recent alarming report suggesting that the severe neurotoxicity observed following treatment with a multiagent chemotherapy regimen might be due to the interaction of vincristine and VP-16-213, the neurologic toxicity data from a randomized trial conducted by the Bowman Gray School of Medicine and the Piedmont Oncology Association in small cell carcinoma of the lung have been analyzed. Of 102 patients evaluable for toxicity, 50 were treated with a combination of cyclophosphamide, adriamycin, and vincristine (CAV) and 52 received this regimen plus VP-16-213. Vincristine dosage was the same in both arms of the study. When analyzed by severity, neurologic complications were similar in both treatment groups: Grade 1-2 neurotoxicity occurred in 55% of patients on both arms and grade 3-4 neurotoxicity was observed in six (12%) patients on the CAV arm and four (8%) on the CAV-VP-16-213 arm. Addition of VP-16-213 to vincristine did not potentiate vincristine-induced neurotoxicity when administered in this dose-schedule relationship.

Adult↗

PubMed2006

A multiagent evolutionary algorithm for constraint satisfaction problems.

With the intrinsic properties of constraint satisfaction problems (CSPs) in mind, we divide CSPs into two types, namely, permutation CSPs and nonpermutation CSPs. According to their characteristics, several behaviors are designed for agents by making use of the ability of agents to sense and act on the environment. These behaviors are controlled by means of evolution, so that the multiagent evolutionary algorithm for constraint satisfaction problems (MAEA-CSPs) results. To overcome the disadvantages of the general encoding methods, the minimum conflict encoding is also proposed. Theoretical analyzes show that MAEA-CSPs has a linear space complexity and converges to the global optimum. The first part of the experiments uses 250 benchmark binary CSPs and 79 graph coloring problems from the DIMACS challenge to test the performance of MAEA-CSPs for nonpermutation CSPs. MAEA-CSPs is compared with six well-defined algorithms and the effect of the parameters is analyzed systematically. The second part of the experiments uses a classical CSP, n-queen problems, and a more practical case, job-shop scheduling problems (JSPs), to test the performance of MAEA-CSPs for permutation CSPs. The scalability of MAEA-CSPs along n for n-queen problems is studied with great care. The results show that MAEA-CSPs achieves good performance when n increases from 10(4) to 10(7), and has a linear time complexity. Even for 10(7)-queen problems, MAEA-CSPs finds the solutions by only 150 seconds. For JSPs, 59 benchmark problems are used, and good performance is also obtained.

Algorithms↗

PubMed2005

Drug-metabolizing enzyme polymorphisms predict clinical outcome in a node-positive breast cancer cohort.

PURPOSE: Adjuvant chemotherapy cures only a subset of women with nonmetastatic breast cancer. Genotypes in drug-metabolizing enzymes, including functional polymorphisms in cytochrome P450 (CYP) and glutathione S-transferases (GST), may predict treatment-related outcomes. PATIENTS AND METHODS: We examined CYP3A4*1B, CYP3A5*3, and deletions in GST mu (GSTM1) and theta (GSTT1), as well as a priori-defined combinations of polymorphisms in these genes. Using a cohort of 90 node-positive breast cancer patients who received anthracycline-based adjuvant chemotherapy followed by high-dose multiagent chemotherapy with stem-cell rescue, we estimated the effect of genotype and other known prognostic factors on disease-free survival (DFS) and overall survival (OS). RESULTS: Patients who carried homozygous CYP3A4*1B and CYP3A5*3 variants and did not carry homozygous deletions in both GSTM1 and GSTT1 (denoted low-drug genotype group) had a 4.9-fold poorer DFS (P = .021) and a four-fold poorer OS (P = .031) compared with individuals who did not carry any CYP3A4*1B or CYP3A5*3 variants but had deletions in both GSTT1 and GSTM1 (denoted high-drug genotype group). After adjustment for other significant prognostic factors, the low-drug genotype group retained a significantly poorer DFS (hazard ratio [HR] = 4.9; 95% CI, 1.7 to 14.6; P = .004) and OS (HR = 4.8; 95% CI, 1.8 to 12.9; P = .002) compared with the high- and intermediate-drug combined genotype group. In the multivariate model, having low-drug genotype group status had a greater impact on clinical outcome than estrogen receptor status. CONCLUSION: Combined genotypes at CYP3A4, CYP3A5, GSTM1, and GSTT1 influence the probability of treatment failure after high-dose adjuvant chemotherapy for node-positive breast cancer.

Adult↗

PubMed2001

Continuous infusion prochlorperazine: pharmacokinetics, antiemetic efficacy, and feasibility of high-dose therapy.

PURPOSE: The purpose of these sequential phase I studies was to evaluate the antiemetic efficacy and pharmacokinetics of high-dose continuous infusion prochlorperazine. METHODS: A total of 52 patients with advanced cancer were treated in two sequential phase I studies utilizing high-dose prochlorperazine. In study 1, designed to investigate the antiemetic effects of dose-intensive prochlorperazine, various cisplatin-based multiagent chemotherapeutic regimens were administered in combination with escalating doses of prochlorperazine. In study 2, a fixed dose of cisplatin (60 mg/m2) was administered over 24 h as a continuous intravenous infusion in combination with infusional high-dose prochlorperazine. Antiemetic efficacy in the first trial was assessed in terms of the number of episodes of nausea, retching, and/or emesis during the 24 h following cisplatin administration. The pharmacokinetics of high-dose prochlorperazine were evaluated in eight patients treated in study 2 at the two dose levels below those at which dose-limiting toxicity was noted. RESULTS: The maximally tolerated dose of prochlorperazine in combination with cisplatin (60 mg/m2 administered as a continuous infusion over 24 h) was 24 mg/h. The dose-limiting toxicity was grade 4 agitation and confusion noted in one patient treated at 26 mg/h. This patient died 3 days following cessation of chemotherapy due to the toxicity of the regimen in combination with the debilitating pulmonary effects of the disease. The mean end of infusion prochlorperazine level at the 24 mg/h dose level was 1.1 microM, a concentration previously reported to be consistent with the reversal of the multidrug resistance phenotype. Two partial responses were observed in study 2. CONCLUSIONS: We conclude that the antiemetic efficacy of high-dose infusional prochlorperazine does not appear to be improved over more convenient bolus administration. However, prochlorperazine levels consistent with those required in vitro for drug resistance reversal are attainable within the dose range having a tolerable toxicity profile.

Adult↗