[Predonation and transfusion in open heart surgery]

The efficacy of predonation of autologous blood in reducing the use homologous blood during open heart surgery was investigated. Between January 1997, and February 1998, predonation and transfusion was studied in 100 consecutive open heart operations (CABG, 77; valve surgery, 17; ASD, 5; myxoma, 1). The guidelines for autologous predonation were as follows: an age < 70 years, a weight > 40 kg and a hemoglobin > 12 g/dl. Patients in NYHA class IV or undergoing emergency operation were excluded. The blood loss during operation ranged from 195 to 1,850 ml (mean; 670 ml), being from 305 to 1,850 ml (723 ml) for CABG, from 260 to 1,020 ml (493.5 ml) for valve surgery and from 195 to 570 ml (342 ml) for ASD. The blood loss was not significantly dependent on sex or age and did not differ elective and emergent operations. Only 36.6% of patients with autologous predonation needed homologous transfusion versus 63.4% of those without predonation. Homologous transfusion was done in only 5% of the those with predonation of 800 ml versus 69% at 400 ml and 71% at 200 ml. In conclusion, autologous blood transfusion is effective for reducing the homologous blood requirement. It also seems that predonation of 800 ml may be sufficient to allow open heart surgery without blood transfusion.

[Clinical study of emergency coronary artery bypass surgery]

Between January, 1996 and December, 1998, 29 patients were undergone emergency coronary artery bypass grafting (CABG) in our institute. Age ranged 34 to 85 years (mean 65 +/- 11 years, male:female = 25:4). Of 29 emergency cases, 3 were hospital death. Hospital mortality rate was 10.7%, which was significantly higher than the hospital mortality of elective CABG (1.4%) during the same period. The necessity of IABP before CABG was 72% in emergency cases (elective surgery: 0%). Thus the use rate of arterial grafts were 86.2% in emergency cases (elective surgery: 100%), the patency of the arterial grafts were 100%. It is important to make stable condition of the patients before the operation, and therefore it is important to make contact closely with the cardiologists for making stable condition and for lowering the operative mortality. And, we should use arterial grafts for the long term result as much as possible if it is an urgent operation.

[New screening method for coagulation abnormality including AT III deficiency during CABG]

In our institute, 1 ml of heparin is administered to the patients undergoing CABG before dissection and mobilization of the internal thoracic arteries (ITAs) and/or right gastroepiploic artery (GEA) to prevent possible thrombosis or coagulation tendency. Two patients with AT III deficiency underwent CABG and one of them died. The aim of this study is to know whether ACT check before and after administration of 1 ml of heparin is useful as a screening test of coagulation abnormalities including AT III deficiency. One hundred patients (84 males and 16 females) undergoing CABG were studied. Age ranged from 41 to 79 years (mean 64.8 +/- 8.0 years). One ml of heparin was administered to all the patients before ITAs and/or GEA were dissected and mobilized. ACT was doubly checked before (control ACT: c-ACT) and after (heparinized ACT: h-ACT) administration of heparin. ACT extension was defined as follows: ACT extension = (c-ACT)-(h-ACT). Mean c-ACT was 124 +/- 12 sec., h-ACT 188 +/- 26 sec. and ACT extension 64 +/- 24 sec. There were only 3 cases which ACT extension were less than 30 sec.: two of them were combined with AT III deficiency and the other was due to insufficient administration of heparin. In conclusion, examination of ACT after 1 ml administration of heparin is new, simple and convenient screening method for coagulation abnormalities including AT III deficiency during CABG.

Hypoxia potentiates ultraviolet A-induced riboflavin cytotoxicity

Flavins are thought to be important chromophores for chronic photo-induced skin injury, but the mechanism is not well known. We have reported that the primary cytotoxicity remaining in ultraviolet A-irradiated riboflavin solution is attributable to hydrogen peroxide. Because the dermis is more hypoxic than the atmosphere, we investigated the cytotoxicity of riboflavin solution during and after ultraviolet A irradiation under hypoxia. Riboflavin solution showed stronger cytotoxicity during irradiation under hypoxia than under air. Riboflavin solution that had been irradiated under hypoxia at lower ultraviolet A doses showed stronger cytotoxicity and contained more hydrogen peroxide than solution irradiated under air at the same doses. At higher ultraviolet A doses, however, the cytotoxicity and hydrogen peroxide quantity were similar in riboflavin solutions irradiated under different oxygen conditions. The effect of a singlet oxygen quencher, sodium azide, on the induction of cytotoxicity and production of hydrogen peroxide by ultraviolet A irradiation of riboflavin solution was examined. The presence of sodium azide in the solution during ultraviolet A irradiation suppressed the cytotoxicity and hydrogen peroxide production to similar levels at various ultraviolet A doses regardless of oxygen conditions. At the maximum suppression by sodium azide, hydrogen peroxide production decreased to 10% of the unsuppressed production. About 40% of the oxygen molecules of hydrogen peroxide produced was thought to be derived from oxygen dissolved in the riboflavin solution.

Pharmacological analysis of etoposide in elderly patients with lung cancer

To analyze the pharmacological characteristics of etoposide in elderly patients, we conducted a Phase I trial of a 14-day administration of oral etoposide on 12 chemotherapy-naive patients, ages 75 years or older, with lung cancer. The pharmacological profiles of etoposide in elderly patients were compared with those of younger patients in our previous studies (H. Minami et al., J. Clin. Oncol., 11: 1602-1608, 1993; H. Minami et al., J. Clin. Oncol., 13: 191-199, 1995; Y. Ando et al., Jpn. J. Cancer Res., 87: 200-205, 1996). The sigmoid Emax model and logistic regression model were used for pharmacodynamic analysis. The maximum tolerated dose for elderly patients was 75 mg/body/day. The apparent oral clearance in elderly patients was 37+/-10 (mean +/- SD) ml/min, which was not different from that in younger patients (44+/-12 ml/min). The area under the concentration-versus-time curve of etoposide over the treatment period (total AUC) that produced a 50% decrease in absolute neutrophil counts was significantly different between elderly and younger patients, 14.3+/-2.5 and 21.6+/-2.7 mg x min/ml, respectively (P = 0.048). The incidence of grade 3 or 4 neutropenia at total AUC of 30 mg x min/ml (corresponding to a plasma concentration of 1.5 microg/ml for 14 days) was 81% in elderly patients but only 48% in younger patients. Although there was no pharmacokinetic difference between elderly and younger patients, equivalent exposure to etoposide resulted in severer myelosuppression in elderly patients. These findings suggest that prolonged etoposide administration with plasma concentration maintained at 1-2 microg/ml may cause severe myelotoxicity in elderly patients.

Low-grade B-cell lymphoma of mucosa-associated lymphoid tissue in the lung: a report of a case with pleural dissemination

A 79-year-old man with an abnormal shadow on a chest radiograph was referred to our hospital for further examination. Open lung biopsy revealed numerous nodules on visceral pleura and the tumor, obtained by wedge resection of the left upper lobe of the lung, consisted of centrocyte-like cells and lymphoplasmacytoid cells, expressing CD20 and CD79a. These cells invaded bronchiolar epithelium to form lymphoepithelial lesions. The pleural-based nodules were similarly composed of the same cells as those in the left upper lobe tumor. To our knowledge, pleural dissemination of low grade B-cell lymphoma of mucosa-associated lymphoid tissue has not been reported previously.

Pharmacokinetics and pharmacodynamics of 9-aminocamptothecin infused over 72 hours in phase II studies

A novel derivative of camptothecin, 9-aminocamptothecin (9-AC), is currently under Phase II evaluation in various cancers. Exceptionally mild toxicities were observed in patients with brain tumors who were treated with anticonvulsants. To investigate a pharmacokinetic interaction between 9-AC and anticonvulsants, and to evaluate the pharmacodynamics of 9-AC, we investigated the clinical pharmacology of 9-AC, administered by a 72-h infusion, in three Phase II studies. Plasma concentrations of total 9-AC (lactone plus carboxylate) at a steady state were measured in 56, 10, and 14 patients with non-small cell lung cancer, malignant glioma, and head and neck cancer, respectively. For lung cancer or glioma patients, 9-AC was infused at 45 (51 patients) or 59 (15 patients) microg/m2/h, and 9-AC was infused at 35.4 microg/m2/h in head and neck cancer patients. All glioma patients had been treated with phenytoin or carbamazepine. 9-AC clearance did not differ among the dosage rates, but differed according to the diseases (P = 0.002). Glioma patients had a higher clearance (1.0-18.0; median, 2.0 liters/h/m2) than lung cancer patients (0.3-5.1; median, 0.9 liters/h/m2). A logistic regression model described the relationship between the 9-AC concentration and the probability of grade 4 neutropenia, which was the main toxicity. Observed incidences of grade 4 neutropenia for patients with model-predicted probability of 0-20%, 20-40%, and 40-100% were 10%, 32%, and 67%, respectively, and corresponded to 9-AC concentration of <54, 54-86, and >86 ng/ml, respectively. Anticonvulsants seem to induce the clearance of 9-AC, and the concentration of 9-AC predicts the probability of grade 4 neutropenia.

Lung carcinoma in patients age younger than 30 years

BACKGROUND

To the authors' knowledge, no study regarding lung carcinoma patients age <30 years has been published. Therefore, this study was undertaken to define the characteristics of lung carcinoma patients age <30 years.

METHODS

Information regarding 26 patients with primary lung carcinoma who were age <30 years was obtained from 10 medical institutions and reviewed retrospectively. For comparison, 304 patients age > or = 30 years who were admitted to the First Department of Internal Medicine at Toyama Medical and Pharmaceutical University between 1980-1996 were studied.

RESULTS

Among the characteristics observed in the group of lung carcinoma patients age <30 years was a high incidence of female gender, no history of smoking, so-called "low grade malignancy," American Joint Committee on Cancer Stage I disease, and previous surgical resection. In addition, a low incidence of squamous cell carcinoma was noted, and a more favorable prognosis was observed.

CONCLUSIONS

The current study noted clinical features that could be defined clearly in lung carcinoma patients age <30 years.

Evaluation of acute aortic dissection by cine-MRI

We investigated operative indication of acute aortic dissection by analyzing the movement of the intimal flap using cine-MRI.

METHODS

Ten consecutive cases of acute aortic dissection diagnosed between December 1997 and September 1998 participated in this study. Six of these patients had in Stanford type A and four Stanford type B aortic dissection. The diagnosis of aortic dissection was based on demonstration of two aortic channels with each cardiac cycle. After obtaining SE(spin-echo) images, gradient echo sequences (FFE) were obtained such that the false lumen was maximally imaged and the intimal flap was depicted perpendicularly. During one RR-interval of ECG, 12 to 16 measurements were recorded and combined in a cineloop mode. We defined the intimal flap, the site of the entry and thrombosis in the false lumen, and evaluated the movement of the intimal flap as the flap movement index (FMI). Maximum and minimum aortic diameters (ADmax, ADmin), as well as maximum and minimum false lumen diameters (FDmax, FDmin) were measured. FMI was defined as[(FDmax/ADmax) - (FDmin/ADmin)]/(FDmin/ADmin) x 100(%).

RESULTS

Total thrombosis was noted in four cases, partial thrombosis in 3, and in the remaining 3 no thrombosis of the false lumen was noted. The FMI ranged between 4% and 87% (mean 26.3 +/- 8.6%). Among the 4 cases with the large FMI of greater than 30%, 3 underwent emergency surgery and were confirmed to have no thrombosis in the false lumen. The fourth case, who had partial thrombosis, underwent medical therapy, but since complete thrombosis in the false lumen never did occur in this case, surgery became absolutely necessary. The other 6 cases with a FMI of less than 30% showed a tendency toward gradual reduction of the false lumen.

CONCLUSION

FMI is a potentially useful parameter in cases with acute aortic dissection to determine whether or not emergency surgery is indicated.

Prognostic factors for short-term survival in patients with stage IV non-small cell lung cancer

Prognostic factors which can forecast short-term survival in patients with stage IV non-small cell lung cancer have not been well evaluated. Characteristics of such factors may be different from those for overall survival, and would be an important eligibility criterion for clinical trials of chemotherapy. We retrospectively analyzed the data of 158 patients with stage IV non-small cell lung cancer whose performance status was 0, 1 or 2. Univariate and multivariate logistic regression models revealed demographic variables which significantly correlated with the survival at 8 or 12 weeks. The univariate model showed the following significant variables: T factor, N factor, number of organs with metastases, grade of performance status, weight loss within 6 months, evidence of metastasis either at bone or lymph node, and lactate dehydrogenase level. The subsequent multivariate model demonstrated that both grade of performance status under 2 and number of metastasized organs less than 3 are important factors for 8- or 12-week survival. The survival rate in patients meeting the two criteria (grade of performance status under 2 and number of metastasized organs less than 3) and in those meeting only one of them was 93% versus 80% at 8 weeks (P = 0.030) and 88% versus 62% at 12 weeks (P < 0.001), respectively. Grade of performance status and number of organs with metastases appear to be important prognostic factors for short-term survival in patients with stage IV non-small cell lung cancer.

Chemical conversion of vibsanin C to vibsanin E and structure of 3-hydroxyvibsanin E from viburnum awabuki

Vibsanin E (4), a tricyclic vibsane-type diterpene, has been prepared in 50% yield from vibsanin C (2), a seven-membered ring vibsane-type diterpene by reaction with BF3.OEt2 at -78 degrees C. This chemical correlation not only established structure, including absolute configurations, but also has demonstrated a possible biosynthetic route to 4 via 2 derived from vibsanin B (1). The structure of 3-hydroxyvibsanin E (5), another example of a tricyclic seven-membered ring vibsane, isolated from the leaves of Viburnumawabuki, has been established by extensive analyses of 2D NMR data and comparison of its spectral data with those of 4.

Does pressure antagonize anesthesia? High-pressure stopped-flow study of firefly luciferase and anatomy of initial flash

The antagonizing effect of high pressure against anesthesia is well known. With purified firefly luciferase, however,. Biophys. J. 60:1309-1314) reported that high pressure did not affect the initial flash intensity. Firefly luciferase emits a burst of light when the substrates luciferin and ATP are added in the presence of O2. The light intensity decays rapidly and the weak light lasts for hours. The initial flash is a transient event and is not in a steady state. The steady state is represented by the slope of the linear part of the integral of the light output. The present study used a high-pressure stopped-flow system to compare the pressure effects on the initial flash intensity and the steady-state light intensity. The flash intensity did not change by the application of hydrostatic pressure in the presence or absence of chloroform or 1-octanol. In contrast, high pressure increased the steady-state light intensity. The application of 12 MPa pressure increased the steady-state light intensity of firefly luciferase inhibited by 5 mM chloroform or 0.7 mM 1-octanol by 19.7% and 18.8%, respectively. When analyzed by the rapid reaction kinetics of the transition state theory, the initial peak intensity represents the total amount of active enzyme and is unrelated to the reaction rate. Anesthetics inhibited the initial flash by unfolding the protein, thereby decreasing the concentration of the active enzyme. Pressure affected the steady-state light intensity by changing the reaction rates.

Toxicity and efficacy of ifosfamide, carboplatin and etoposide (modified ICE) as a salvage chemotherapy in Japanese patients with relapsed or refractory aggressive non-Hodgkin's lymphoma

The combination of ifosfamide, carboplatin and etoposide (modified ICE), was evaluated for its toxicity and activity in relapsed or refractory aggressive non-Hodgkin's lymphoma. Twenty patients, 14-69 years of age, with relapsed (19 cases) or refractory (one case) aggressive non-Hodgkin's lymphoma were treated with modified ICE therapy, consisting of ifosfamide 6 g/m2 (1.2 g/m2 day 1-5), carboplatin 400 mg/m2 (day 1) and etoposide 500 mg/m2 (100 mg/m2 day 1-5). The regimen was repeated at approximately 28-day intervals. All patients had undergone a doxorubicin-containing regimen before modified ICE therapy. Median total dose of previously received doxorubicin was 406 mg/m2 (range: 200-825 mg/m2). The median interval from diagnosis to modified ICE therapy was 9.4 months (range: 3.6-121 months). Two patients achieved CR and five achieved PR out of 16 patients with measurable lesions (response rate 43.8%; 95% confidence interval 19.0-68.6%). Median overall survival was 227 days (range: 41-552 days) from the start of modified ICE therapy. Myelosuppression was the most serious toxicity, namely 16 patients (80%) and 11 patients (55%) showed grade 4 neutropenia and grade 4 thrombocytopenia after the first course, respectively. Modified ICE therapy might be an active regimen with acceptable toxicity as a salvage chemotherapy in aggressive non-Hodgkin's lymphoma.

Identification of 1,6- and 1,8-dinitropyrene isomers as major mutagens in organic extracts of soil from Osaka, Japan

The organic extracts of soil collected at parks in residential areas in Osaka and neighboring cities in the Kansai area, Japan, showed mutagenicity in Salmonella typhimurium strain TA98 in the presence or absence of a mammalian metabolic activation system (S9 mix). The soil extracts from Ibaraki and two different sites in Osaka, i.e., Sumiyoshi-ku and Minato-ku, were mutagenic in strain TA100 as well as in strain TA98. Direct-acting mutagenicity of soil extracts from Sumiyoshi-ku and Minato-ku toward strain TA98 were 66 or more times higher than that of the other cities. Both extracts exerted stronger mutagenicity in strains YG1021 and YG1024 than TA98 and TA100, and the potency was especially high in strain YG1024: Sumiyoshi-ku, 153 000 revertants/g of soil; and Minato-ku, 246 000 revertants/g of soil. Two mutagenic compounds (I and II) were isolated from the Soxhlet extract of soil from the park in Sumiyoshi-ku by repetitive separation using normal-phase and reversed-phase column chromatography. By comparing the mass and UV spectra and retention times for HPLC on two individual ODS columns of compounds I and II with those of authentic chemicals, we identified these two compounds as 1,6- and 1,8-dinitropyrene (DNPy) isomers. Amounts of DNPy isomers in soil from Sumiyoshi-ku and Minato-ku were 1.7-2.2 ng/g. Forty-three percent and 40% of the mutagenicity of soil from Sumiyoshi-ku and Minato-ku could be attributed to these DNPy isomers, respectively.

Indirect-response model for the time course of leukopenia with anticancer drugs

BACKGROUND

Because both the nadir count and the duration of leukopenia after chemotherapy with anticancer drugs are important, a pharmacodynamic model describing the entire time course of leukopenia is valuable. In this study, a pharmacodynamic model was developed to simulate leukopenia.

METHODS

The model was developed with the 3-hour infusion data of paclitaxel. A concentration-time curve of paclitaxel for each patient estimated by a 3-compartment pharmacokinetic model was used as input to the model, which had 2 compartments corresponding to leukocytes in bone marrow and peripheral blood, respectively. Differentiation stages of myeloid cells sensitive to anticancer drugs were assumed, and exposure to a drug during their sensitive period as a function of time was used to inhibit the production of leukocytes in bone marrow. The model was validated by fitting the data of 24-hour infusion of paclitaxel or 14-day infusion of etoposide.

RESULTS

Successful fitting of the leukopenia after a 3-hour infusion of paclitaxel was achieved. The following parameters were estimated: lag-time, 58 +/- 38 (mean +/- SD) hours before the leukocyte count started to decline; exposure giving 50% inhibition of leukocyte production (IC), 12.1 +/- 6.1 microg x h/mL; and sensitive period, 288 +/- 64 hours. These estimations were within physiologic ranges. In validation, leukopenia after 24-hour infusion of paclitaxel or 14-day infusion of etoposide was also explained by the model. Age was significantly negatively correlated with IC of paclitaxel (P = .039).

CONCLUSIONS

This mechanistic model describes the time course of leukopenia and may provide a platform for pharmacodynamic analysis of anticancer drugs.

Acute myelogenous leukemia with monosomy 7, inv(3) (q21q26), involving activated EVI 1 gene occurring after a complete remission of lymphoblastic lymphoma: a case report

A 42-year-old female with a mediastinal tumor and massive pleural effusion ws admitted to our hospital in June 1993. Biopsy revealed lymphoblastic lymphoma. She had no evidence of distant metastasis except pleural effusion. Bone marrow examination revealed a normal karyotype (46, XY). The patient had been progression-free for more than 1 year after achieving complete remission by induction, consolidation and maintenance therapy according to the standard chemotherapy and involved-field radiation for lymphoblastic lymphoma. From May 1996 progressive leukopenia and thrombocytopenia developed. The diagnosis of refractory anemia with excess of blasts (RAEB) was made. Subsequently, in November 1996, she developed acute myelogenous leukemia (AML), M4 type by FAB classification. The karyotype of MDS and AML clones involved inversion (3) (q21q26) and monosomy 7. The EVI 1 gene was examined and was proved to be rearranged and activated. This may be the first case among the therapy-related cases of MDS/AML reported whose karyotypes were followed and in which the mRNA expression of EVI 1 gene involved was directly proved in the leukemogenesis process of chemotherapy-induced secondary MDS and AML.

Dehydration of Hydrated Bilayer of Dipalmitoylphosphatidylcholine Caused by Beryllium Ion: Evidence from a Differential Scanning Calorimetry of Bilayer Phase Transition

The effect of polyvalent metal ions Be2+, Mg2+, Ca2+, Sr2+, Ba2+, and La3+ on the phase transition behavior of hydrated bilayer of dipalmitoylphosphatidylcholine (DPPC) was investigated by differential scanning calorimetry (DSC) in relation to their ability to induce the aggregation of DPPC vesicles. The addition of the metal ions other than Be2+ provided DSC thermograms characteristic to a fully hydrated DPPC bilayer. By the addition of Be2+, the endothermic peak associated with the bilayer phase transition was shifted to that corresponding to partially dehydrated DPPC bilayer, which was reported by Kodama et al. (Biochem. Biophys. Acta 689, 567, 1982). This demonstrates that Be2+ causes dehydration of DPPC head group in hydrated bilayer and supports the speculation that the unusual property of Be2+ to induce the aggregation of PC vesicles is attributed to the destruction of repulsive hydration force due to the partial dehydration of vesicular surface. Copyright 1998 Academic Press.

[Promotion of phagocytosis and prevention of phagosome-lysosome (P-L) fusion in human peripheral blood monocytes by serotype specific glycopeptidolipid (GPL) antigen of Mycobacterium avium complex (MAC)]

Mycobacterium avium complex (MAC) is one of the most important opportunistic pathogens co-infected with HIV (AIDS) and a typical intracellular parasitic bacteria similar to M. tuberculosis. It is also noticed that M. avium infection causes immunosuppression especially in the cellular immunity of host animals, and specific serotype-subspecies such as sero-2, -4 or -8 can be isolated frequently in human infection. Furthermore, the prognosis after infection differs by the serotypes and serotype-4 shows heavy infection in general, while serotype-16 shows rapid improvement. Therefore, we have been interested in the immunomodifying activity of surface glycopeptidolipid (GPL) antigen. However, to date, no information has been available on the virulence factor of MAC related directly with intracellular bactericidal activity. Recently, we have tested the effect of various GPLs purified form MAC complex on phagocytic processes of human peripheral blood monocytes (PBMC). We have used GPL-coated heat-killed staphylococcal cells to be phagocytosed by PBMC, and phagosome-lysosome (P-L) fusion was estimated by the acridine orange staining of fused vesicles including bacteria. It was revealed that the serotype-4, -12 and -17 GPLs showed strong phagocytosis promotion and marked inhibition of P-L fusion, while serotype-9, -13, -16 and -19 GPLs showed neither promotion of phagocytosis, nor inhibition of P-L fusion in phagocytic cells. Serotype-5, -7, -8 and -10 GPLs showed stimulation of both phagocytosis and P-L fusion, concomitantly. These effects may be due to unknown interaction between specific carbohydrate chain of MAC and phagocytic cell membranes, and serotype-4, -12 and -17 GPLs may be one of the possible virulence factors in MAC.

Study of cohort-specific consent and patient control in phase I cancer trials

PURPOSE

To address the challenging ethical dilemmas created from the participation of advanced cancer patients in phase I trials, we assessed the feasibility of a clinical trial design that uses an interactive informed consent process in which patient-subjects can choose to become directly involved in decisions of dose escalation.

PATIENTS AND METHODS

Subjects were advanced cancer patients in the Hematology/Oncology Clinics at the University of Chicago who were eligible to participate in a phase I trial in which they underwent a three-step informed consent process that used cohort-specific consent and allowed them the option to choose their own doses of the chemotherapeutic agents under study, vinorelbine (NVB) and paclitaxel (TAX), within predetermined limits. NVB and TAX were administered in conventional 21- to 28-day cycles for two cycles while on study. Dose escalation occurred when a patient-subject chose a higher untested dose after they received information on all previously assessable patient-subjects. In addition to the phase I trial itself, a survey that consisted of structured interviews, which sought to evaluate patients' experiences with the interactive subject-choice phase I trial design and consent process, was conducted with participating subjects. The phase I trial itself sought to determine the associated toxicities of the agents under study. The survey results were compared with a similar survey of a matched control population of subjects who participated in other concurrently active conventional phase I trials at our institution.

RESULTS

Twenty-nine patient-subjects participated in the phase I trial, with 24 who agreed to and completed the survey interviews. Seventy-six percent of patient-subjects opted to choose their dose of the agents under study, and 28% chose the highest available doses. More than half of the patient-subjects (56%) felt some degree of comfort in being asked to choose their dose of chemotherapy, with 53% stating that being asked to choose their dose made them feel in control, fully informed, or content. However, there were no statistically significant improvements in objective measures of the informed consent process, which included surveyed subjects' stated understanding of either provided information about phase I trials and alternatives to trial participation or of the research purpose of phase I trials. By making choices, the group of patients in the interactive subject choice trial changed the size of the dose cohorts and modified the process of dose escalation in this phase I study.

CONCLUSION

Although complex, our innovative phase I trial design is feasible. In addition to the use of cohort-specific consent, the trial design may reduce the magnitude of many of the commonly recognized ethical dilemmas associated with this form of clinical research, which include difficulties with information provision and the understanding of possible risks and benefits of phase I trial participation, through direct subject involvement in research decision making by otherwise potentially vulnerable cancer patients.