Survey estimates of fishable biomass following a mass mortality in an Australian molluscan fishery.

Mass mortality events are relatively uncommon in commercially fished populations, but when they occur, they reduce production and degrade ecosystems. Observing and documenting mass mortalities is simpler than quantifying the impact on stocks, monitoring or predicting recovery, and re-establishing commercial fishing. Direct survey measures of abundance, distribution and harvestable biomass provide the most tenable approach to informing decisions about future harvests in cases where stock collapses have occurred because conventional methods have been disrupted and are less applicable. Abalone viral ganglioneuritis (AVG) has resulted in high levels of mortality across all length classes of blacklip abalone, Haliotis rubra Leach, off western Victoria, Australia, since May 2006. Commercial catches in this previously valuable fishery were reduced substantially. This paper describes the integration of research surveys with commercial fishermen's knowledge to estimate the biomass of abalone on AVG-impacted reefs. Experienced commercial abalone divers provided credible information on the precise locations of historical fishing grounds within which fishery-independent surveys were undertaken. Abalone density estimates remained low relative to pre-AVG levels, and total biomass estimates were similar to historical annual catch levels, indicating that the abalone populations have yet to adequately recover. Survey biomass estimates were incorporated into harvest decision tables and used with prior accumulated knowledge of the populations to determine a conservative harvest strategy for the fishery.

Spinal cord penetration of intrathecally administered cytarabine and methotrexate: a quantitative autoradiographic study.

Carcinomatous meningitis is an increasingly common complication of systemic cancer. Treatment usually involves the use of intrathecal methotrexate or cytarabine, which have been reported to be toxic to the spinal cord. This study was performed to determine the penetration and distribution of intrathecally administered chemotherapy within the spinal cord. Tritiated methotrexate and cytarabine were administered intraventricularly and by lumbar puncture to New Zealand White rabbits. The extent and pattern of penetration of drug into the spinal cord were determined using quantitative autoradiographic techniques. The results demonstrate that 1 hour after administration 67%-99% of the total area of the spinal cord sections were exposed to these intrathecally administered agents. The pattern of distribution of the labeled drugs was inhomogeneous and was not dependent on the agent or the route of administration. High drug levels were seen in the area of the substantia gelatinosa and peripheral white matter which correspond to the location of pathological changes seen in the spinal cords of patients with neurotoxicity from intrathecal chemotherapy. This rapid and extensive penetration of intrathecally administered chemotherapy may offer insight into the myelopathy observed with these treatments.

Desmin mutation responsible for idiopathic dilated cardiomyopathy.

BACKGROUND: Idiopathic dilated cardiomyopathy, of which approximately 20% of cases are familial (FDCM), is a primary myocardial disorder characterized by ventricular dilatation and impaired systolic function. It is a common cause of heart failure and the need for cardiac transplantation. Although 6 chromosomal loci responsible for autosomal dominant FDCM have been mapped by linkage analysis, none of these genes have been identified. By use of the candidate-gene approach, actin was identified recently as being responsible for dilated cardiomyopathy. Considerable evidence suggests desmin, a muscle-specific intermediate filament, plays a significant role in cardiac growth and development. METHODS AND RESULTS: To determine whether a defect of desmin induces dilated cardiomyopathy, 44 probands with FDCM underwent clinical evaluation and DNA analysis. Diagnostic criteria, detected by echocardiography, consisted of ventricular dimension of >/=2.7 cm/m(2) with an ejection fraction

Favorable outcome of invasive aspergillosis in patients with acute leukemia.

During a 2-year period, 15 of 110 patients (14%) admitted for intensive therapy of acute leukemia associated with prolonged deep granulocytopenia developed documented invasive aspergillosis (IA). Antemortem diagnosis was accomplished in 14, and 13 of 15 (87%) survived the infection. Because of the high success rate, we reviewed the courses of the 15 patients to assess factors associated with this favorable outcome. Eleven presented with pulmonary IA; early symptoms occurred at a mean 21.6 days of granulocytopenia (less than 100/muL) and included refractory fever in 14 and pulmonary signs or symptoms in 11. Primary necrotic chest wall lesions associated with Hickman catheters developed in four at a mean 11 days of granulocytopenia, followed by pulmonary involvement. All 15 patients had chest radiographs during granulocytopenia, with 14 (93%) demonstrating pulmonary infiltrates and/or nodules at a mean 20.6 days of aplasia. Nine patients had lung computerized tomography (CT) scans, revealing nodular infiltrates in one patient and a characteristic zone of low attenuation surrounding a mass-like infiltrate in seven other patients, which was found to be diagnostic of IA. Subsequent CT scans performed during and following bone marrow recovery showed progression to cavitation followed by either complete resolution or minimal pulmonary scarring. Eleven patients developed IA during empiric amphotericin B (Amp-B) therapy (0.5 mg/kg/d) for fever refractory to antibacterial antibiotics. Fourteen patients received high-dose Amp-B (1.0 to 1.5 mg/kg/d), which was started within a mean of 2.2 days of first clinical findings; 13 survived. Ten patients received 5-fluorocytosine in addition to high dose amp-B. Survival was similar regardless of presentation, as 91% with primary pulmonary IA and 75% presenting with chest wall lesions survived. All 13 surviving patients had complete granulocyte recovery at a mean 33.8 days. Nephrotoxicity (creatinine greater than 2.0 mg/dL) was observed in seven patients during therapy for IA, but was transient in all seven. We conclude IA can be successfully treated in the deeply granulocytopenic patient provided that it is recognized and treated early, and provided that antifungal therapy is aggressive and is continued until granulocyte recovery occurs.

Early evaluation of combined fluorouracil and leucovorin as a radiation enhancer for locally unresectable, residual, or recurrent gastrointestinal carcinoma. The North Central Cancer Treatment Group.

PURPOSE: To develop a tolerable regimen of fluorouracil (5-FU), low-dose leucovorin, and radiation, and to obtain an early estimate of therapeutic effectiveness. PATIENTS AND METHODS: Forty patients with locally unresectable or recurrent gastrointestinal carcinoma were studied (pancreas, n = 22; rectum and sigmoid, n = 10; gastric, n = 6; other, n = 2). Irradiation therapy was administered in 1.8-Gy fractions 5 days per week, with total doses ranging from 45 to 54 Gy. 5-FU 400 mg/m2/d plus leucovorin 20 mg/m2/d, both by rapid intravenous injection, were administered for 3 or 4 days during the first and fifth weeks of radiation. 5-FU 425 mg/m2/d plus leucovorin 20 mg/m2/d were administered for 4 days at 4 weeks following radiation and for 5 days at 9 weeks. RESULTS: Major toxicities with upper abdominal treatment were nausea, vomiting, weight loss, and leukopenia. A tolerable dosage regimen was radiation at 45 Gy with 4 days of 5-FU plus leucovorin during the first week and 3 days during the last week with postradiation chemotherapy. Major toxicities with pelvic radiation were diarrhea and leukopenia. A tolerable regimen was 54 Gy with 4 days of 5-FU plus leucovorin during the first and fifth week followed by the postradiation chemotherapy. Median survival durations for pancreatic and rectal/sigmoid carcinomas are 13 months and 31 months, respectively. Five patients have no evidence of disease from 38 to 50 months after the onset of therapy (rectal, n = 2; stomach, n = 2; pancreas, n = 1). CONCLUSION: We have developed patient-tolerable regimens for combined 5-FU plus leucovorin followed by radiation to the abdomen and to the pelvis. The favorable results observed in locally unresectable disease allow cautious optimism for possible effectiveness in the surgical adjuvant setting, a possibility currently being tested in national trials of rectal and gastric carcinoma.

Sequential intrahepatic fluorodeoxyuridine and systemic fluorouracil plus leucovorin for the treatment of metastatic colorectal cancer confined to the liver.

PURPOSE: Extrahepatic metastasis represents a frequent pattern of disease progression when fluorodeoxyuridine (FUDR) is given by the intraarterial route for the treatment of unresectable colorectal liver metastases. Systemic fluorouracil (5-FU) plus leucovorin was added to intrahepatic FUDR to prolong the duration of disease control. METHODS: Only patients with colorectal cancer who had evidence of unresectable metastases confined to the liver were eligible. Laparotomy was performed to establish arterial perfusion of the liver. Cycles of intrahepatic FUDR followed by a 1-week rest period then intravenous chemotherapy with 5-FU plus leucovorin were administered until maximal regression of hepatic metastases. Maintenance chemotherapy with 5-FU plus leucovorin was then given until disease progression. RESULTS: Fifty-seven patients entered this trial; four patients (7%) were ineligible and 13 (23%) did not receive any chemotherapy on study because of findings at laparotomy. The 40 eligible patients who began chemotherapy are included in the statistical analyses. Twenty-five patients (62% of those who received chemotherapy) experienced regression of liver metastases. The median time to tumor progression was 9 months, but only 3% remained progression-free at 24 months. The median survival duration was 18 months. Toxicity was tolerable with no cases of biliary sclerosis. One treatment-related fatality due to sepsis was observed. CONCLUSION: Although short-term treatment results appear to be somewhat better than we have previously observed with intrahepatic FUDR alone, the sequential regimen did not have an impact on long-term, progression-free survival in patients with unresectable liver metastases. We are now investigating this regimen as surgical adjuvant therapy in selected patients following hepatic metastasectomy where this aggressive approach might have a greater therapeutic effect in the minimal residual disease setting.

Phase II trial of nitrogen mustard, vincristine, and procarbazine in patients with recurrent glioma: North Central Cancer Treatment Group results.

PURPOSE: Previous investigators have reported responses in 52% of patients treated with mechlorethamine (nitrogen mustard), vincristine, and procarbazine (MOP) for recurrent glioma. To confirm these promising results, we conducted a phase II prospective study. PATIENTS AND METHODS: Sixty-three patients with histologic confirmation of recurrent glioma were treated with the MOP regimen. Patients with or without prior chemotherapy received nitrogen mustard 3 mg/m2 or 6 mg/m2, respectively, intravenously on days 1 and 8 plus vincristine 2 mg/m2 intravenously on days 1 and 8, and procarbazine 100 mg/m2 orally on days 1 to 14. Cycles were repeated every 28 days. RESULTS: Of 61 patients assessable for response, eight responded (13%), with one complete response (CR). Responses were as follows: low-grade gliomas, 19%; anaplastic astrocytomas, 11%; anaplastic oligodendrogliomas or oligoastrocytomas, 25%; and glioblastomas, 4.3%. The most common toxicity was myelosuppression with leukocyte nadirs less than 1,000/microL in 23% and platelet nadirs less than 25,000/microL in 13% of patients. Two patients died of infection in the setting of neutropenia. Nonhematologic toxicity included neurosensory changes in 21% of patients (severe in 3%) and severe dermatologic reactions in 8%. In multivariate analysis, Eastern Cooperative Oncology group (ECOG) performance status (PS) was the best predictor for response to chemotherapy (P=.01) and time to progression (P=.008), while PS and grade were the most important predictors of survival (P=.002 and .05, respectively). CONCLUSION: This study did not confirm the high response rate previously reported in recurrent gliomas. Patients with recurrent anaplastic oligodendrogliomas or oligoastrocytomas and recurrent low-grade gliomas had the highest response rates (25% and 19%, respectively). In multivariate analysis, ECOG PS was the best predictor of response, while PS and tumor grade were the most important predictors of survival.

Immunotherapy of advanced malignancy by direct gene transfer of an interleukin-2 DNA/DMRIE/DOPE lipid complex: phase I/II experience.

PURPOSE: We have completed a phase I study, followed by three phase I/II studies, in patients with metastatic melanoma, renal cell carcinoma (RCC), and sarcoma in order to evaluate the safety, toxicity, and antitumor activity of Leuvectin (Vical Inc, San Diego, CA), a gene transfer product containing a plasmid encoding human interleukin (IL)-2 formulated with the cationic lipid 1, 2-dimyristyloxypropyl-3-dimethyl-hydroxyethyl ammonium bromide/dioleyl-phosphatidyl-ethanolamine (DMRIE/DOPE) and administered intratumorally. PATIENTS AND METHODS: Twenty-four patients were treated in the phase I study. Leuvectin doses were 10 microg, 30 microg, or 300 microg weekly for 6 weeks. In three subsequent phase I/II studies, a total of 52 patients (18 with melanoma, 17 with RCC, and 17 with sarcoma) were treated with further escalating doses of Leuvectin: 300 microg twice a week for 3 weeks, 750 microg weekly for 6 weeks, and 1,500 microg weekly for 6 weeks. RESULTS: There were no drug-related grade 4 toxicities and only one grade 3 toxicity, but the majority of patients experienced mild constitutional symptoms after treatment. In the phase I/II studies, 45 patients were assessable for response (14 with RCC, 16 with melanoma, and 15 with sarcoma). Two patients with RCC and one with melanoma have achieved partial responses lasting from 16 to 19 months and continuing. In addition, two RCC, three melanoma, and six sarcoma patients had stable disease lasting from 3 to 18 months and continuing. The plasmid was detected by polymerase chain reaction assay in the posttreatment samples of 29 of 46 evaluated patients. Immunohistochemistry studies on serial biopsy specimens showed increased IL-2 expression and CD8(+) infiltration after treatment in the tumor samples of several patients (12 and 16, respectively). CONCLUSION: Direct intratumoral injection of Leuvectin is a safe and possibly effective immunotherapeutic approach in the treatment of certain tumor types.

Regulatory role of fructose-2,6-bisphosphate in pancreatic islet glucose metabolism remains unsettled.

Fructose-2,6-P2 was measured in perifused, isolated rat pancreatic islets. Fructose-2,6-P2 was present in pancreatic islets at low levels approximately equal to fructose-2,6-P2 content of liver from fasted rats. In islets perifused with glucose at physiologic concentrations, fructose-2,6-P2 was increased from 0.8 microM in the presence of 5.5 mM glucose to 1.0 microM at 10 mM glucose and 1.3 microM at 16.7 mM glucose, but did not increase further at higher glucose concentration. Therefore, only modest increases in the phosphofructokinase-1 activator, fructose-2,6-P2, occur at glucose concentrations stimulating insulin secretion.

Adaptation of glycolytic enzymes: glucose use and insulin release in rat pancreatic islets during fasting and refeeding.

Starvation refeeding experiments were conducted in rats to test the hypothesis that adaptation of glucokinase (the high Km component of glucose phosphorylation) could be the major determinant of glucose metabolism of pancreatic islet cells and of glucose-stimulated insulin release. It was found that glucokinase of islet homogenates, glucose use by intact isolated islets, and glucose-induced insulin release as studied in a perifusion system were decreased after 24 h of fasting, whereas P-fructokinase and 3-P-glyceraldehyde DH were unaltered. After extended fasting (e.g., 120 h) all three enzymes were decreased but glucose use did not change any further. Refeeding normalized all parameters. These and previous results support the concept that glucokinase serves as the adaptive beta-cell glucoreceptor relating blood glucose to insulin release.

Identification of glucokinase as an alloxan-sensitive glucose sensor of the pancreatic beta-cell.

Alloxan inactivated glucokinase in intact, isolated pancreatic islets incubated in vitro. Inactivation of glucokinase was antagonized by 30 mM glucose present during incubation of islets with alloxan. Glucokinase partially purified from transplantable insulinomas or rat liver was inactivated by alloxan with a half-maximal effect at 2-4 microM alloxan. Inactivation of purified glucokinase was antagonized by glucose, mannose, and 2-deoxyglucose in order of decreasing potency but not by 3-O-methylglucose. Glucose anomers at 6 and 14 mM were discriminated as protecting agents, with the alpha-anomer more effective than the beta-anomer. Glucokinase was not protected from alloxan inactivation by N-acetylglucosamine, indicating that the reactive site for alloxan is not the active site; therefore, glucose may protect glucokinase by inducing a conformational change. Glucokinase is thought to be the glucose sensor of the pancreatic beta-cell. The finding that glucokinase is inactivated by alloxan and protected by glucose with discrimination of its anomers similar to inhibition of glucose-stimulated insulin secretion by alloxan supports this hypothesis and appears to explain the mechanism for inhibition of hexose-stimulated insulin secretion by this agent and the unique role of glucose and mannose as protecting agents.

Regulation of glucose metabolism in pancreatic islets.

We evaluated the possible role of islet glucokinase in controlling the rate of islet glucose metabolism, and thereby the rate of glucose-induced insulin release. The activities of glucokinase, hexokinase, P-fructokinase, and glyceraldehyde-P dehydrogenase were quantitated in sonicated or isotonically homogenized islet preparations using pyridine nucleotide-dependent fluorometric assays. In sonicates, about 1/4 of the islet glucose phosphorylating activity was due to an enzyme with kinetic properties similar to glucokinase; 3/4 of the activity was due to hexokinase. The procedure for determining islet glucokinase activity was improved by centrifuging isotonic islet homogenates at 12,000 x g. The supernatant fraction was enriched for glucokinase. About 1/2 of the glucose phosphorylating activity in this fraction was due to glucokinase and 1/2 was due to hexokinase. The glucokinase activity in islet homogenates was !23 of the activity of hexokinase, 1/40 of the activity of P-fructokinase, and 1/400 of the activity of glyceraldehyde-P dehydrogenase. Detailed concentration dependency curves of glucose and mannose utilization were also obtained with intact isolated pancreatic rat islets. Glucose and mannose usage in islets was governed by two superimposed hyperbolic systems differing in Km and Vmax. A high Km system (Km for glucose 11 mM and for mannose 21 mM) predominated. A low Km system (Km for glucose 215 and for mannose 530 microM) contributed about 15% to the total activity. The available data with intact islets could be rationalized by the existence of two distinct hexose phosphorylating enzymes with differing capacities and kinetic properties. These enzymes, tentatively identified as glucokinase and hexokinase, could coexist in the same cell or could be distributed among different cell types. The possible physiologic significance of these results is discussed, emphasizing the idea of dual control of glycolysis and insulin release by glucokinase and hexokinase. An earlier proposal that glucokinase serves as glucoreceptor of beta-cells [J. Biol. Chem. 243:2730 (1968)] is greatly strengthened by the present studies.

Phase I trial of temozolomide (NSC 362856) in patients with advanced cancer.

Temozolomide (TMZ) is a new imidazotetrazine derivative with early clinical activity in glioma and melanoma. The purpose of this Phase I study is to characterize the toxicity, pharmacokinetics, and antitumor activity of TMZ administered on an oral 5-day schedule to patients with or without prior exposure to nitrosourea (NU). Thirty-six eligible patients received a total of 77 cycles of therapy with TMZ administered p.o. at doses ranging from 50 mg/m2/day to 250 mg/m2/day for 5 days, every 4 weeks. Separate dose escalations were carried out in patients, with or without prior exposure to NU. Pharmacokinetic studies were performed during the first cycle of treatment on days 1 and 5. Dose-limiting toxicity was thrombocytopenia, and the maximally tolerated doses for patients with and without prior exposure to NU were 150 mg/m2/day for 5 days (total dose, 750 mg/m2) and 250 mg/m2/day for 5 days (total dose, 1250 mg/m2), respectively. Significant (grade 3 or higher) thrombocytopenia was observed in six patients during cycle 1. The median times to nadir and recovery were 17 and 15 days, respectively. Nonhematological toxicity was generally manageable and consisted of fatigue, nausea, and vomiting. There were two complete responses (one glioma and one melanoma) in patients without prior NU. No objective responses were seen in patients with prior NU treatment. Pharmacokinetic studies showed rapid absorption with a mean time to peak concentration of 60 min and mean t1/2 of 109 min (range, 80-121 min). The area under the curve and the peak plasma concentrations were linear over the dose range of 50-250 mg/m2/day. The mean apparent oral clearances on day 1 for patients with and without prior NU exposure were 102+/- 27 and 115+/- 22 ml/min/m2, respectively. Apparent oral clearances on days 1 and 5 were found to differ with respect to NU exposure (P = 0.047). Renal clearance of the parent drug and its metabolism to 3-methyl-2, 3-dihydro-4-oxoimidazo[5,1-d]tetrazine-8-carboxylic acid were minor pathways of TMZ elimination. We conclude that TMZ is well tolerated in this oral 5-day schedule with dose-limiting thrombocytopenia and that it has promising activity in glioma and melanoma. The recommended doses for Phase II studies in patients with and without prior NU are 125 mg/m2/day for 5 days and 225 mg/m2/day for 5 days, respectively.

Aerosol granulocyte macrophage-colony stimulating factor: a low toxicity, lung-specific biological therapy in patients with lung metastases.

The objective was to study the feasibility of granulocyte macrophage-colony stimulating factor (GM-CSF) delivery to the lung using an aerosol in humans. A Phase I dose escalation study provided GM-CSF at three dose levels as a twice-a-day (BID) x 7 days schedule. Pulmonary functions were monitored using a remote spirometry device. Blood counts were checked at the beginning and end of each week of GM-CSF nebulization. If no toxicity was encountered, patients rested for 7 days and then were treated at the next dose level. Six of seven patients were successfully dose escalated from 60 microg/dose BID x 7 days, to 120 microg/dose BID x 7 days, then 240 microg/dose BID x 7 days. No toxicity was seen. Comparison of day 0 and day 7 blood leukocyte counts showed no significant increases in either leukocyte numbers or percentage of neutrophils. Pulmonary functions test changes were minor. No significant change in forced vital capacity, FEV1, peak flow, or FEF 25-75 related to either time or dose level was observed. One patient's lung metastases progressed. The other five patients received an additional 2-6 months of intermittent aerosol GM-CSF at dose level 3 without side effects. One patient with Ewing's sarcoma has a complete response, and a patient with melanoma had a partial response; the other three had stabilization of pulmonary metastases for 2-6 months. Aerosol delivery of GM-CSF is feasible, safe, and possibly effective. Aerosol cytokine delivery may achieve effective immunological activation against cancer in the lung and is worthy of further study.

Phase III evaluation of octreotide versus chemotherapy with 5-fluorouracil or 5-fluorouracil plus leucovorin in advanced exocrine pancreatic cancer: a North Central Cancer Treatment Group study.

There continues to be a need for new systemic approaches for the treatment of advanced pancreatic cancer. The purpose of this study was to compare the antitumor activity of the somatostatin analogue octreotide to 5-fluorouracil chemotherapy in a Phase III setting. Eighty-four patients with an Eastern Cooperative Oncology Group performance status of 0 or 1 and limited tumor volume were randomized to receive octreotide 200 microg three times daily or 5-fluorouracil with or without leucovorin. After the first 12 patients had been randomized to octreotide, we increased the dose in the remaining patients to 500 microg three times daily. This change was based on early reports in other studies, suggesting that our original dose may not have been effective and that higher doses of octreotide were well tolerated. A planned interim analysis performed after 84 patients were enrolled demonstrated inferior time to progression and survival for the patients randomized to octreotide. Further accrual to the octreotide arm of this protocol was therefore terminated. Octreotide in doses of 200-500 microg three times daily does not delay progression or extend survival in patients with advanced pancreatic cancer compared with treatment with 5-fluorouracil with or without leucovorin.

Priming tissue-specific cellular immunity in a phase I trial of autologous dendritic cells for prostate cancer.

We attempted to induce therapeutic immunity against prostate-derived tissues in patients suffering from progressive hormone-refractory metastatic prostate carcinoma. Thirteen patients were treated with two infusions, 1 month apart, of autologous dendritic cells (APC8015) preexposed ex vivo to PA2024, a fusion protein consisting of human granulocyte/macrophage-colony stimulating factor (GM-CSF) and human prostatic acid phosphatase (PAP). The infusions were followed by three s.c. monthly doses of PA2024 without cells. Three groups of patients each received PA2024 at 0.3, 0.6, or 1.0 mg/injection. All Ps were two-sided. Treatment was well tolerated. After infusions of APC8015, patients experienced only mild (grade 1-2) short-lived fever and/or chills, myalgia, pain, and fatigue. One patient developed grade 3 fatigue. Four patients developed mild local reactions to s.c. PA2024. Twelve patients were evaluable for response to treatment. Circulating prostate-specific antigen levels dropped in three patients. T cells, drawn from patients after infusions of APC8015, but not before, could be stimulated in vitro by GM-CSF (P = 0.0004) and PAP (P = 0.0001), demonstrating broken immune tolerance against these two normal proteins. Injections of PA2024 did not influence the reactivity of T cells against PAP and GM-CSF. However, antibodies to GM-CSF and, to a much lesser extent, to PAP reached maximum titers only after two or even three injections of PA2024, showing that directly injected PA2024 was involved in stimulation of humoral immunity. Dendritic cells exposed to antigen ex vivo can induce antigen-specific cellular immunity in prostate cancer patients, warranting further studies of this mode of immunotherapy.

Phase I dose-finding and pharmacokinetic trial of irinotecan hydrochloride (CPT-11) using a once-every-three-week dosing schedule for patients with advanced solid tumor malignancy.

A Phase I study was performed to determine the maximum tolerated dose (MTD), toxicities, and pharmacokinetic profile of irinotecan (CPT-11) and its active metabolites when given on a once-every-3-week schedule. Thirty-four patients with advanced refractory solid malignancies were treated with CPT-11 (240-340 mg/m2) administered as a 90-min i.v. infusion every 3 weeks. Patients were divided into two groups: those with and those without prior abdominal/pelvic (AP) radiotherapy. Gastrointestinal toxicity (nausea, vomiting, and diarrhea) and hematological toxicity (leukopenia and neutropenia) were dose-limiting side effects. Other common toxicities included anorexia, asthenia, and acute cholinergic symptoms (abdominal cramps, diaphoresis, and lacrimation). For patients with no prior AP radiation therapy, the MTD was determined to be 320 mg/m2, whereas those with prior AP radiation therapy had a MTD of 290 mg/m2. Dose-proportional increases in the mean area under the concentration-time curves for CPT-11, SN-38, and SN-38G were not observed over the narrow dose range studied. Mean values of terminal phase half-life, clearance, terminal phase volume of distribution, and steady-state volume of distribution for CPT-11 were 12.4 +/- 1.8 h, 13.0 +/- 3.8 liters/h/m2, 234 +/- 83 liters/m2, and 123 +/- 38 liters/m2, respectively. The pharmacodynamic analyses indicated the strongest correlation to be between SN-38 area under the concentration-time curves and neutropenia (p = 0.60; P = 0.001). A total of five responses (one complete response and four partial responses) were observed in the cohort of 32 patients with previously treated metastatic colorectal carcinoma. In conclusion, gastrointestinal toxicity and hematological toxicity were the dose-limiting toxicities of CPT-11 when administered as a 90-min infusion every 3 weeks. In this trial, the recommended Phase II starting dose for patients with no prior AP radiation therapy was found to be 320 mg/m2; for patients with prior AP radiation, the recommended Phase II starting dose was 290 mg/m2. This once-every-3-week schedule has been incorporated into a Phase I trial of CPT-11 combined with 5-fluorouracil and leucovorin.

Decreased protein binding and thiopental kinetics.

Thiopental kinetics and protein binding were determined in seven surgical patients with chronic renal failure and a thiopental free fraction of 28.0 +/- 6.5% (SD) and in seven age- and weight-matched normal surgical patients with a thiopental free fraction of 15.7 +/- 2.4%. Thiopental clearance, based upon total plasma concentrations, rose from 3.2 +/- 0.6 ml/kg/min in the normal group to 4.5 +/- 1.1 ml/kg/min in the chronic renal failure group. Volume of distribution at steady state, also based on total drug concentrations, rose from 1.9 +/- 0.5 l/kg in the normal group to 3.0 +/- 1.0 l/kg in the chronic renal failure group. These changes in clearance and volume of distribution at steady state are secondary to changes in free drug distribution and elimination. When kinetics were calculated from free drug concentrations, the intrinsic clearance, unbound volume of distribution at steady state, and free fraction in tissues in the normal and renal failure groups did not differ substantially. These data suggest that the kinetic changes based on total drug concentrations are secondary to changes in free fraction in plasma. In chronic renal failure patients, the underlying rate and extent of thiopental distribution and elimination are much the same as in normal patients.

Alleviation of cancer anorexia and cachexia: studies of the Mayo Clinic and the North Central Cancer Treatment Group.

Anorexia and cachexia are common clinical problems of many patients with advanced cancer. Approximately 20 years ago, a controlled, clinical study demonstrated that dexamethasone could stimulate appetites of patients with advanced gastrointestinal cancer without causing any apparent effect on patient weight or survival. More recently, two double-blind, placebo-controlled trials investigated cyproheptadine and megestrol acetate in patients with cancer anorexia/cachexia. The first of these studies suggested that cyproheptadine could mildly stimulate appetite without causing any discernible effect on patient weight. Megestrol acetate, on the other hand, can clearly cause an increase in patient-perceived appetite and food intake and can also lead to substantial nonfluid weight gain in a proportion of patients with cancer anorexia/cachexia. Ongoing studies have been designed to better study the appetite-enhancing effects of megestrol acetate. In addition, current studies are evaluating the effect of the drug hydrazine sulfate on the appetite and weight status of patients with advanced lung or colon cancer.

Treatment of epidural cord compressions from Hodgkin's disease with chemotherapy. A report of two cases and a review of the literature.

Epidural cord compressions are a frequent and serious problem for patients with cancer. Standard treatment for these lesions includes local irradiation with or without surgery. Herein are reported two cases of epidural cord compression from Hodgkin's disease that responded dramatically to systemic chemotherapy. A review of the literature reveals reports of successful chemotherapy in the treatment of seven patients with epidural metastases secondary to lymphomas and 15 secondary to a variety of other tumors. The use of systemic chemotherapy is an increasingly important therapeutic option for treatment of epidural cord compressions in carefully selected patients.