Clinical course and risk factors of neurotoxicity following cisplatin in an intensive dosing schedule

An intensive weekly regimen of cisplatin was administered to 66 patients with solid cancer in doses varying from 70 to 85 mg/m(2) . The occurrence of sensory neuropathy was prospectively examined by assessment of neuropathic signs and symptoms and measurement of vibration perception threshold (VPT). Evaluation was performed before initiation of therapy and during follow-up until 3-12 months after the last cycle of cisplatin. A mild or moderate neuropathy developed in 47% of patients at 2 weeks after treatment This neuropathy continued to deteriorate until approximately 3 months after cessation of chemotherapy leading to a mild or moderate neuropathy in 71% of patients and a severe neuropathy in 9% of patients. Thereafter we observed a gradual but incomplete recovery. The high incidence of neuropathy we found may be explained by the prolonged observation period compared with earlier reports. The only factor correlated with severity of neuropathy was the cumulative dose of cisplatin, while there was no association with either pre-treatment VPT, age, sex, tumor type or co-treatment with etoposide. The progressing course up to approximately 3 months after the end of treatment underscores the need for prolonged follow-up in future studies on cisplatin neuropathy.-

A randomized trial in ovarian cancer (OC) of early treatment of relapse based on CA125 level alone versus delayed treatment based on conventional clinical indicators (MRC OV05/EORTC 55955 trials)

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Background: Serum CA125 often rises several months before women with OC have symptoms or clinical signs of relapse. OV05/55955 was designed to determine whether there were benefits from early treatment based on a confirmed elevation of CA125 levels versus delaying treatment until clinically indicated. Methods: Women with OC in clinical complete remission after first-line platinum-based chemotherapy and a normal CA125 were registered. CA125 was measured every 3 months but patients and investigators were blinded to the results, which were only monitored by the trials units. If CA125 levels exceeded twice the upper limit of normal, patients were randomized to either immediate treatment or to remain having blinded CA125 measurements with treatment commencing when clinical or symptomatic recurrence appeared. Patients in both arms were treated according to standard local practice. The primary outcome measure was overall survival. The study was designed to detect a 10% improvement in 2-year overall survival in the immediate treatment arm with at least 85% power and 5% significance level (2-sided). Results: 1,442 patients were registered from 59 sites in 10 countries between 1996 and 2005. Randomization closed on March 31, 2008 with 527 patients (264 immediate and 263 delayed) randomized and when the targeted number of events (deaths) were reached. 915 patients have not been randomized due to: no CA125 rise and no relapse (48%); relapse with or without CA125 rise (30%); death (6%); patient withdrawal (14%); or other reasons (2%). For randomized patients baseline characteristics were well balanced between the groups. Median age at registration was 61 years; 81% were FIGO stage III/IV. Second-line chemotherapy started a median of 5 months earlier in the immediate arm. With a median follow-up of 49 months from randomization and a total of 351 deaths, there was no evidence of a difference in overall survival between the immediate and delayed arms, hazard ratio 1.01, 95% CI 0.82–1.25, p = 0.91. Conclusions: There is no survival benefit from early treatment based on a raised serum marker level alone, and therefore no value in the routine measurement of CA125 in the follow-up of ovarian cancer patients.

No significant financial relationships to disclose.

A randomized trial in ovarian cancer (OC) of early treatment of relapse based on CA125 level alone versus delayed treatment based on conventional clinical indicators (MRC OV05/EORTC 55955 trials)

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The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

No significant financial relationships to disclose.

[Adjuvant chemotherapy in patients operated on for early ovarian carcinoma]

The desirability of adjuvant chemotherapy in patients with early ovarian carcinoma, i.e. a carcinoma limited to the internal genitalia (FIGO stage I-IIA), has long been controversial. Until recently, the few randomised studies that had been performed showed no improvement in survival after adjuvant chemotherapy, but the numbers of patients were too low to yield convincing proof. Complete surgical staging in patients with early ovarian carcinoma is of utmost importance to define the stage of the disease. In case of inadequate staging, there is a 24% risk (range 16-46%) that undetected tumour deposits will remain in the abdominal cavity following surgery, so that the estimated stage will be too low. The combined results of the two largest randomised clinical trials on early ovarian carcinoma to date have recently been published: the 'Adjuvant chemotherapy in ovarian neoplasm' (ACTION) trial, coordinated by the European Organisation for Research and Treatment of Cancer (EORTC), and the 'International collaboration in ovarian neoplasm' (ICON-1) trial; they showed a significant benefit from adjuvant chemotherapy on overall and progression-free survival in early ovarian cancer. The ACTION trial (448 patients), however, also showed that adjuvant chemotherapy only improved the overall and disease-free survival significantly in inadequately staged patients. In the patients who had undergone optimal surgical staging, adjuvant chemotherapy had no effect on the prognosis. In the ICON-1 study (477 patients) there was a favourable effect of adjuvant chemotherapy in the whole population. Analysis of this trial, however, shows that most probably only a very small percentage of these patients had undergone optimal surgical staging. Based on the published results, the best policy for the treatment of patients with early ovarian cancer is felt to be to make every effort to achieve optimal surgical staging and to reserve the burdensome adjuvant chemotherapy for those patients in whom optimal (re)staging is not feasible.

Reduced expression of BAX is associated with poor prognosis in patients with epithelial ovarian cancer: a multifactorial analysis of TP53, p21, BAX and BCL-2

Traditional clinicopathological features do not predict which patients will develop chemotherapy resistance. The TP53 gene is frequently altered in ovarian cancer but its prognostic implications are controversial. Little is known on the impact of TP53-downstream genes on prognosis. Using molecular and immunohistochemical analyses we examined TP53 and its downstream genes p21, BAX and BCL-2 in ovarian tumour tissues and have evaluated the results in relation to clinico-pathological parameters, clinical outcome and response to platinum-based chemotherapy. Associations of tested factors and patient and tumour characteristics were studied by Spearman rank correlation and Pearsons chi2 test. The Cox proportional hazard model was used for univariate and multivariate analysis. The associations of tested factors with response was tested using logistic regression analysis. TP53 mutation, p21 and BCL-2 expression were not associated with increased rates of progression and death. Expression of TP53 was associated with a shorter overall survival only (relative hazard rate [RHR] 2.01, P = 0.03). Interestingly, when combining TP53 mutation and expression data, this resulted in an increased association with overall survival (P = 0.008). BAX expression was found to be associated with both progression-free (RHR 0.44, P = 0.05) and overall survival (RHR 0.42, P = 0.03). Those patients who simultaneously expressed BAX and BCL-2 had a longer progression-free and overall survival compared to patients whose tumours did not express BCL-2 (P = 0.05 and 0.015 respectively). No relations were observed between tested factors and response to platinum-based chemotherapy. We conclude that BAX expression may represent a prognostic indicator for patients with ovarian cancer and that the combined evaluation of BAX and BCL-2 may provide additional prognostic significance.

Dose and schedule-finding study of oral topotecan and weekly cisplatin in patients with recurrent ovarian cancer

Both weekly cisplatin chemotherapy and single agent topotecan have proven to be effective in recurrent ovarian cancer. Preclinical data show synergism between cisplatin and topotecan. Side effects for this combination are drug sequence dependent and predominantly haematologic. Since preclinical data suggest that Cremophor EL (CrEL), the formulation vehicle of paclitaxel, has a protective effect on haematological toxicity of cisplatin, CrEL was added to the combination cisplatin and topotecan. In this phase I study, escalating doses of oral topotecan administered on day 1, 2, 8, 9, 15, 16, 29, 30, 36, 37, 43, 44 were combined with weekly cisplatin 70 mg m(-2) d(-1) on day 1, 8, 15, 29, 36, 43 (scheme A) or with the presumably less myelotoxic sequence weekly cisplatin day 2, 9, 16, 30, 37, 44 (scheme B). In scheme C, CrEL 12 ml was administered prior to cisplatin in the sequence of Scheme A. 18 patients have received a total of 85 courses. In scheme A 4/10 patients, all treated with topotecan 0.45 mg m(-2) d(-1), experienced DLT: 1 patient had vomiting grade 4, 1 patient had grade 4 neutropenia >5 days, 1 patient had >2 weeks delay due to thrombocytopenia and 1 patient due to neutropenia. Both patients in scheme B (topotecan 0.45 mg m(-2) d(-1)) had DLT due to a delay > 2 weeks because of prolonged haematological toxicity. No DLT was observed in the first 3 patients in scheme C (topotecan 0.45 mg m(-2) d(-1)). However, 2 out of 3 patients treated at dose level topotecan 0.60 mg m(-2)d(-1) in scheme C experienced DLT due to >2 weeks delay because of persistent thrombocytopenia or neutropenia. We conclude that there is a modest clinical effect of CrEL on haematological toxicity for this cisplatin-based combination regimen, which seems to reduce these side effects but does not really enable an increase of the oral topotecan dose.

Phase II study of mitomycin-C and cisplatin in disseminated, squamous cell carcinoma of the uterine cervix. A European Organization for Research and Treatment of Cancer (EORTC) Gynecological Cancer Group study

The aim of this study was to investigate the tumour response rate and toxicity of a combination chemotherapy consisting of mitomycin-C and cisplatin in patients with disseminated squamous-cell carcinoma of the uterine cervix. Chemotherapy consisted of mitomycin, 6 mg/m(2) intravenously (i.v.), and cisplatin, 50 mg/m(2) given i.v., both administered on day 1 of each cycle. The regimen was repeated at 4-weekly intervals. Mitomycin-C/cisplatin were used to treat 33 evaluable patients aged 29-67 years (median: 50 years). All patients except 1 had previously been treated with either surgery, radiation or both. At the initiation of chemotherapy, 8 patients had loco-regional and disseminated disease and 25 women had only distant metastases. The overall response rate was 42% (95% confidence interval (CI): 26-61%). Five complete and nine partial responses were observed with a median duration of response of 7.9 months (95% CI: 3.7-23.5 months). 9 patients had stable disease and 10 developed progressive disease during mitomycin-C/cisplatin-treatment. World Health Organization (WHO) grade III/IV side-effects were documented in 15 women, of whom 10 had gastro-intestinal toxicity, 3 had haematological toxicity, 1 had alopecia and 1 developed an allergic reaction to cisplatin. There were neither drug-related deaths nor severe or irreversible renal or hepatic dysfunction or peripheral neuropathy. The median progression-free survival was 5.0 months (95% CI: 3.6-6.2 months) for all patients and 10.5 months (95% CI: 6.2-15.2 months) for the responders. The median overall survival was 11.2 months (95% CI: 6.5-18.4 months).The mitomycin-C/cisplatin combination showed antitumour activity in the treatment of advanced or recurrent squamous-cell carcinoma of the uterine cervix. The regimen was well tolerated and could be administered on an outpatient basis.

Randomized phase III trial of bleomycin, vindesine, mitomycin-C, and cisplatin (BEMP) versus cisplatin (P) in disseminated squamous-cell carcinoma of the uterine cervix: an EORTC Gynecological Cancer Cooperative Group study

PURPOSE

Three previous mitomycin-cisplatin-based chemotherapy trials conducted within the EORTC Gynecological Cancer Cooperative Group (GCCG) in patients with disseminated squamous-cell carcinoma of the uterine cervix (SCCUC) suggested that with such regimens a higher overall response rate and a higher complete response rate could be obtained compared to what might have been expected from cisplatin alone. In that respect the combination of bleomycin, vindesine (Eldesine), mitomycin C and cisplatin (BEMP) was the most promising. In the present study BEMP has been compared with the best single agent, cisplatin (P) in the expectation that improved response rates might translate into a better survival.

PATIENTS AND METHODS

Eligible patients were those with SCCUC and disseminated measurable disease outside previously irradiated areas, aged < or = 75 years, with a WHO performance status < or = 2 and adequate bone marrow, renal, hepatic and pulmonary function, who gave consent according to regulations followed in individual institutions. Patients were randomized to BEMP: E 3 mg/m2 day 1, P 50 mg/m2 day 1, B 15 mg (24-hour infusion) day 2-4 and M 8 mg/m2 (at alternate cycles), or P 50 mg/m2. The first four cycles were given every 3 weeks (induction phase). Subsequent cycles were given every four weeks (maintenance phase), during which B was deleted from BEMP (MEP). Patients failing on P could be treated with BEM. Of the 287 patients entered, 235 were eligible and 201 evaluable for response.

RESULTS

BEMP induced a significantly higher response rate than P (42% vs. 25%, P = 0.006). There was no difference in complete response rate (11% vs. 7%). BEMP was significantly more toxic than P (+/- BEM), both with respect to hematologic and nonhematologic toxicities. After a median follow-up of 6.1 years, survival curves were not significantly different. Median progression-free survival and overall survival were 5.3 and 10.1 months with BEMP and 4.5 and 9.3 months with P (+/- BEM), respectively. In a multivariate analysis of prognostic factors for survival, a lower age (P = 0.003), a lower performance status (P = 0.0001) and a short (<1 year) interval since diagnosis (P = 0.0152) were all associated with an increased risk of dying. For progression-free survival, lower age, prior radiotherapy, locoregional involvement and no prior surgery were associated with a high risk. Treatment with BEMP or P had no significant impact on survival, but for progression-free survival there was a trend in favor of BEMP (P = 0.0893). Adjusting for prognostic factors did not change the effect of treatment.

CONCLUSIONS

Combination chemotherapy with BEMP produces more toxicity and more responses compared with cisplatin alone in patients with disseminated SCCUC, but this does not translate into a better survival. Therefore, in the palliative setting single-agent cisplatin should remain the standard therapy for these patients.

Advanced ovarian cancer

Ovarian cancer spreads early in the disease into the abdomen. An en bloc resection of the tumor, according to surgical principle, is not possible in patients with high-stage ovarian cancer. At surgery, large pelvic tumor lesions are found together with multiple tumor lesions involving the omentum, bowel, and mesentery together with a diffuse peritoneal carcinomatosis and diaphragmatic involvement. A multimodality approach with cytoreductive surgery and taxol platinum-based chemotherapy is therefore the mainstay of treatment of advanced ovarian cancer. The size of residual disease after surgery is one of the most important prognostic factors for survival. Patients with an optimal tumor cytoreduction (residual lesions smaller than 1 cm) have a significant longer survival (almost two times the median survival) than patients with larger residual lesions. This holds true even for patients with International Federation of Gynecology and Obstetrics (FIGO) stage IV disease. Patients in whom all macroscopic tumor is resected do have the longest survival. The 2-year survival of patients with a radical resection of all macroscopic tumors is 80%, in contrast to less than 22% for the patients with lesions larger than 2 cm. An optimal primary cytoreductive surgery can generally be performed in 30% to 50% of patients. Only in more experienced gynecologic oncology centers is the percentage as high as 85%, but sometimes at the cost of an increased morbidity and even mortality. The worse prognosis of the patients with a suboptimal primary cytoreductive surgery can be improved by an interval cytoreductive surgery after platinum-containing induction chemotherapy. The median survival and progression-free survivals are significantly lengthened by cytoreductive surgery. After more than 5-years follow-up there is still a significant survival benefit: the 5-year survival of the surgery patients was 24% versus 13% for the no-surgery patients (P = 0.0032). All patients, including those with unfavorable prognostic factors (stage IV disease, peritonitis carcinomatosis, or ascites at primary surgery), and even patients with stable disease after induction chemotherapy, seem to benefit from interval cytoreductive surgery. The increase in progression-free survival and overall survival does outweigh the morbidity associated with interval debulking surgery, which is not different from those associated with primary surgery.

D-TRP-6-LHRH (Triptorelin) is not effective in ovarian carcinoma: an EORTC Gynaecological Cancer Co-operative Group Study

Between March and September 1988, 74 patients with progressive ovarian cancer after prior platinum-based therapy were treated with the luteinizing hormone-releasing hormone (LHRH) agonist Triptorelin (Decapeptyl degrees). Treatment consisted of i.m. injection of 3.75 mg of microencapsulated Triptorelin on days 1, 8 and 28 followed by 4-weekly injections until tumor progression. No objective responses were observed. Eleven out of 68 evaluable patients (16%) had stable disease. The median progression-free survival was 5 months in patients with disease stabilization and 2 months for all evaluable patients. The median survival for patients with disease stabilization was 17 months, whereas for all patients it was 4 months. The treatment was well tolerated; the only reported adverse events were incidental hot flushes. This study showed that the LHRH agonist Triptorelin has only modest efficacy in patients pretreated with platinum-containing chemotherapy.

Phase I pharmacologic study of oral topotecan and intravenous cisplatin: sequence-dependent hematologic side effects

PURPOSE

In in vitro studies, synergism and sequence-dependent effects were reported for the combination of topotecan and cisplatin. Recently, an oral formulation of topotecan became available. This phase I study was performed to assess the feasibility of the combination of oral topotecan and cisplatin, the pharmacokinetic interaction, and sequence-dependent effects.

PATIENTS AND METHODS

Topotecan was administered orally (PO) daily for 5 days in escalating doses and cisplatin was given intravenously (IV) at a fixed dose of 75 mg/m(2) either before topotecan administration on day 1 (sequence CT) or after topotecan administration on day 5 (sequence TC) once every 3 weeks. Patients were treated in a randomized cross-over design.

RESULTS

Forty-nine patients were entered onto the study; one patient was not eligible. Sequence CT induced significantly more severe myelosuppression than did sequence TC, and the maximum-tolerated dosage of topotecan in sequence CT was 1.25 mg/m(2)/d x 5. In sequence TC, the maximum-tolerated dosage of topotecan was 2.0 mg/m(2)/d x 5. Dose-limiting toxicity consisted of myelosuppression and diarrhea. Pharmacokinetics of topotecan and cisplatin were linear over the dose range studied; no sequence-dependent effects were observed. In addition, topotecan did not influence the protein binding of cisplatin or the platinum-DNA adduct formation in peripheral leukocytes in either sequence.

CONCLUSION

The recommended dosages for phase II studies involving patients like the patients in our study are topotecan 1.25 mg/m(2)/d PO x 5 preceded by cisplatin 75 mg/m(2) IV day 1 once every 3 weeks, and topotecan 2.0 mg/m(2)/d PO followed by cisplatin 75 mg/m(2) IV day 5. No pharmacokinetic interaction could be discerned in our study. The antitumor efficacy of both schedules should be evaluated in a randomized phase II study.

The orally administered P-glycoprotein inhibitor R101933 does not alter the plasma pharmacokinetics of docetaxel

This Phase I study was performed to assess the feasibility of combining docetaxel with the new P-glycoprotein inhibitor R101933 and to determine the dose limiting toxicity of this combination. Fifteen patients received oral R101933 alone at a dose escalated from 200 to 300 mg twice daily (b.i.d.; cycle 0), an escalating i.v. dose of docetaxel (60, 75, and 100 mg/m2) as a 1-h infusion (cycle 1), and the combination (cycle 2 and further). Dose limiting toxicity consisting of mucositis and neutropenic fever was reached at the combination of docetaxel, 100 mg/m2, and R101933, 300 mg b.i.d., and the maximum tolerated dose was established at docetaxel, 100 mg/m2, and R101933, 200 mg b.i.d. Plasma concentrations of R101933 achieved in patients were in the same range as required in preclinical rodent models to overcome paclitaxel resistance. The plasma pharmacokinetics of docetaxel were not influenced by the R101933 regimen at any dose level tested, as indicated by plasma clearance values of 26.5 +/- 7.78 liters/h/m2 and 23.4 +/- 4.52 liters/h/m2 (P = 0.15) in cycles 1 and 2, respectively. These findings indicate that the contribution of a P-glycoprotein inhibitor to the activity of anticancer chemotherapy can now be assessed in patients for the first time independent of its effect on drug pharmacokinetics.

Phase I study of 3-week schedule of irinotecan combined with cisplatin in patients with advanced solid tumors

PURPOSE

To assess the feasibility, pharmacokinetic interaction, and possible sequence-dependent effects of the irinotecan/cisplatin combination given every 3 weeks, and to assess the influence of additional granulocyte colony-stimulating factor (G-CSF) on the hematologic toxicity.

PATIENTS AND METHODS

Patients who had received no more than one prior combination chemotherapy regimen or two single-agent regimens were entered. Treatment consisted of a 90-minute irinotecan infusion followed by a 3-hour cisplatin infusion on day 1, with cycles repeated once every 3 weeks. After the maximum-tolerated dose was determined, the sequence of administration was reversed. In a separate cohort of six patients, we assessed the effect of G-CSF on the experienced hematologic toxicity and dose-intensity. Irinotecan doses ranged from 175 to 300 mg/m(2) and cisplatin doses ranged from 60 to 80 mg/m(2).

RESULTS

Fifty-two patients entered the study; one was not eligible, and two were not assessable for response. Twenty-five patients were pretreated, and 26 were not. Fifty-one patients received a total of 223 courses. The dose-limiting toxicity was a combination of neutropenic fever, diarrhea, and fatigue at a dose level combining irinotecan 300 mg/m(2) with cisplatin 80 mg/m(2). Neutropenia was common (grades 3 to 4, 68%). Irinotecan pharmacokinetics were linear over the dose range studied. No sequence-dependent side effects were observed. Tumor responses included three complete responses and eight partial responses.

CONCLUSION

For phase II studies, we recommend irinotecan 260 mg/m(2) combined with cisplatin 80 mg/m(2) once every 3 weeks for chemotherapy-naive patients in good physical condition, and irinotecan 200 mg/m(2) combined with cisplatin 80 mg/m(2) for other patients.

Phase I and pharmacologic study of BMS-181174 given as a 6 h infusion every 4 weeks to patients with advanced solid tumors

BMS-181174, a new mitomycin C (MMC) analog, showed more activity than the parent compound in tumor xenografts. In a phase I study with a 5-30 min slow bolus administration, hematologic and vascular toxicity were observed as major side effects. A prolonged infusion was suggested to circumvent the vascular toxicity. In this phase I study BMS-181174 was administered as a 6 h infusion every 4 weeks; the doses studied were 3.2, 6.4, 11.5, 19.0, 32.0, 50.0, 75.0 and 100 mg/m2. Twenty-eight patients were enrolled in the study, the majority with colorectal cancer. Hematologic side effects consisted of thrombocytopenia, and mild leuko- and granulocytopenia. The most distressing non-hematologic side effect was vascular toxicity consisting of phlebosclerosis and phlebitis, becoming dose limiting at 100 mg/m2. One patient developed a hemolytic uremic syndrome at a cumulative dose of 350 mg/m2. Pharmacokinetic data are available for 24 patients. The AUC ranged from 3.35 to 41.49 (microg x h/ml) and was highly correlated with the dose administered (r = 0.83). The kinetics appeared to be linear. One patient with metastatic colon cancer had a partial response of liver metastases. BMS-181174 is a MMC analog with a toxicity profile comparable to that of the parent compound. As doses above 50 mg/m2 are complicated by vascular toxicity precluding multiple administrations, further exploration of BMS-181174 will not be performed.

Clinical pharmacokinetics of doxorubicin in combination with GF120918, a potent inhibitor of MDR1 P-glycoprotein

Previous clinical investigations with doxorubicin indicated that modulators of P-glycoprotein dramatically decrease the systemic clearance of the drug, which complicates the interpretation of toxicity and response data. In the present study, we examined the pharmacokinetics of doxorubicin and GF120918, a novel potent P-glycoprotein inhibitor, in cancer patients in a search for more selective modulation of multidrug resistance (MDR). Seven cohorts (46 patients) received sequential treatments with doxorubicin alone by a 5 min i.v. bolus (50-75 mg/m2), oral GF120918 alone (50 mg q.d.-400 mg b.i.d.), and the combination of doxorubicin and GF120918. Serial blood and urine samples were taken during both treatment courses and analyzed for doxorubicin and its metabolite doxorubicinol by a liquid chromatographic assay. The pharmacokinetic characteristics of doxorubicin in the presence or absence of GF120918 indicate a very minor overall effect of the modulator, except at the highest combined dose level (i.e. 75 mg/m2 plus 400 mg b.i.d.). A limited number of patients experienced significantly increased exposure to doxorubicinol upon combined treatment, which was associated with concomitantly higher plasma levels of GF120918. Sigmoidal maximum-effect models revealed significant correlations (p<0.02) between the area under the curve of doxorubicinol and the percent decrease in neutrophils and platelets. Sigmoidicity factors in the fitted Hill equation were similar between both treatment courses, suggesting no pharmacodynamic potentiation of doxorubicinol myelotoxicity by GF120918. Our data indicate that GF120918 at the tested doses of combination treatment achieves plasma concentrations that reverse MDR in experimental models and it lacks the significant kinetic interaction with doxorubicin observed previously with other modulators. Hence, it may be possible in future trials to assess the contribution of a potent inhibitor of P-glycoprotein activity to the toxicity and activity of doxorubicin with the knowledge that profound plasma pharmacokinetic interactions are unlikely.

Drug-administration sequence does not change pharmacodynamics and kinetics of irinotecan and cisplatin

In this study, 11 patients with solid tumors were randomized to receive irinotecan (CPT-11; 200 mg/m2) as a 90-min i.v. infusion, immediately followed by cisplatin (CDDP; 80 mg/m2) as a 3-h i.v. infusion in the first course and the reversed sequence in the second course or vice versa. No significant differences in any toxicity were observed between the treatment schedules (decrease in absolute neutrophil count, 74.7 +/- 18.3 versus 80.3 +/- 18.0%; P = 0.41). CPT-11 lactone clearance was similar to single agent data and not significantly different between study courses (60.4 +/- 17.1 versus 65.5 +/- 16.3 liter/h/m2; P = 0.66). The kinetic profiles of the major CPT-11 metabolites SN-38, SN-38 glucuronide, 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidinolcarbonyloxycamptothecine (APC), and 7-ethyl-10-[4-N-(1-piperidino)-1-amino]carbonyloxycamptothecine (NPC) were also sequence independent (P > or = 0.20). In addition, CPT-11 had no influence on the clearance of nonprotein-bound CDDP (40.8 +/- 16.7 versus 50.3 +/- 18.6 liter/h/m2; P = 0.08) and the platinum DNA-adduct formation in peripheral leukocytes in either sequence (1.94 +/- 2.20 versus 2.42 +/- 1.62 pg Pt/microg DNA; P = 0.41). These data indicate that the toxicity of the combination CPT-11 and CDDP is schedule independent and that there is no mutual pharmacokinetic interaction.

Phase I and pharmacologic study of oral (PEG-1000) 9-aminocamptothecin in adult patients with solid tumors

PURPOSE

9-Amino-20(S)-camptothecin (9-AC) is a specific inhibitor of topoisomerase-I. Recently, a bioavailability of approximately 48% for the oral PEG-1000 formulation was reported. We conducted a phase I and pharmacokinetic study of the oral PEG-1000 formulation of 9-AC to define the maximum-tolerated dose, toxicity profiles, pharmacokinetic-dynamic relationships, and preliminary antitumor activity in patients with solid tumors.

PATIENTS AND METHODS

Patients were treated with oral (PEG-1000) 9-AC given once a day for 7 or 14 days at doses ranging from 0.25 to 1.1 mg/m(2)/d; cycles were repeated every 21 days. For pharmacokinetic analysis, plasma sampling was performed on days 1 and 6 or 8 of the first course using a validated high-performance liquid chromatographic assay.

RESULTS

Thirty patients were entered onto the study; three patients were not assessable for toxicity and response. Twenty-seven patients received a total of 89 courses. The dose-limiting toxicities (DLTs) were myelosuppression and diarrhea at a dose of 1.1 mg/m(2)/d for 14 days. Pharmacokinetics showed a substantial interpatient variation of the area under the plasma concentration-time curve (AUC) of 9-AC. The intrapatient variability was extremely small. A significant correlation was observed between the percentage decrease in WBC count and the AUC of 9-AC lactone (r(2) = 0.86). One partial response was noted in a patient with metastatic colorectal cancer.

CONCLUSION

DLTs in this phase I study of oral 9-AC daily for 14 days every 21 days were myelosuppression and diarrhea. The recommended dose for phase II studies is 0.84 mg/m(2)/d. In view of the substantial interpatient variability in AUC and the availability of a limited sampling model, a pharmacokinetic guided phase II study should be considered.

A phase I/II study of combined weekly systemic cisplatin and locoregional hyperthermia in patients with previously irradiated recurrent carcinoma of the uterine cervix

We investigated the feasibility and the anti-tumour activity of weekly cisplatin and the simultaneous application of local hyperthermia in patients with a pelvic recurrence of cervical cancer in previously irradiated area. Dose levels of cisplatin 60 mg m(-2), 70 mg m(-2) and 80 mg m(-2) were studied. Treatment objective of hyperthermia was the achievement of a tumour temperature of > or = 42 degrees for 60 min, during cisplatin administration. The protocol advised six weekly cycles of combined treatment. Nineteen patients, median age 47 years (range 26-71), were treated. A total of 89 cycles of combined treatment were administered. Even at the highest dose level of cisplatin, 80 mg m(-2) weekly, no dose-limiting toxicity was observed. Leucocytopenia at scheduled retreatment resulted in 1 or 2 weeks postponement in five cases. Neurotoxicity and renal toxicity were mild or absent. Maximum tumour temperatures achieved ranged 39.7-43.6 degrees C, mean 41.6+/-0.7 degrees C. All 19 patients were evaluable for response. One patient achieved a complete response that lasted 20 months, and nine patients achieved a partial response for a median duration of 6 months (range 4-50+ months), for an overall response rate of 53%. One patient subsequently underwent salvage surgery and currently remains free of disease at 4 years. We found that this combined hyperthermia-dose-intensive cisplatin regimen was well-tolerated. The true impact of the combination of cisplatin and locoregional hyperthermia can only be answered in a randomized study. Nonetheless, based on existing data on the poor efficacy of cisplatin in pelvic recurrent cervical cancer, we believe that the combined modality approach of weekly hyperthermia plus dose-intensive cisplatin is an attractive regimen, particularly if subsequent salvage surgery is available.

Phase I study of high-dose epirubicin in platinum-pretreated patients with ovarian carcinoma

BACKGROUND

In vitro data demonstrated a dose-response relationship for doxorubicin in ovarian cancer (OC) cell lines. However, this dose-response question for doxorubicin was never carefully addressed in OC patients. These data and the more favorable toxicity profile of the anthracycline analogue epirubicin prompted us to study high-dose epirubicin (HDE) in relapsed OC patients.

PATIENTS AND METHODS

This phase I study included 19 OC patients with measurable or evaluable disease and no more than one prior (cisplatin-containing) chemotherapy regimen. Dose escalation was not allowed in individual patients. Epirubicin was administered by rapid intravenous infusion (<5 min) once every 3 weeks and studied at the following dose levels: 120, 135, 150, 180 and 200 mg/m2 (at least 3 patients per dose level). None of the patients received hematopoietic growth factors. We defined the maximum tolerated dose (MTD) as the dose at which we observed WHO grade 4 hematologic toxicity in >/=50% and/or WHO grade 3 nonhematologic toxicity in >/=30% of the patients.

RESULTS

The MTD was 200 mg/m2, with DLT being both hematologic (leukopenia and/or thrombocytopenia) and nonhematologic (mucositis). Objective responses were observed in 6 patients (response rate 32%), 3 of them occurring in 10 patients with primary platinum resistance.

CONCLUSIONS

HDE is tolerable and has activity in second-line after cisplatin-based chemotherapy in OC patients. The recommended dose for phase II trials in such patients is 150 mg/m2, with escalation to 180 mg/m2 if toxicity permits.

A comparison of clinical pharmacodynamics of different administration schedules of oral topotecan (Hycamtin)

Prolonged exposure to topotecan in in vitro and in vivo experiments has yielded the highest antitumor efficacy. An oral formulation of topotecan with a bioavailability of 32-44% in humans enables convenient prolonged administration. Pharmacokinetic/pharmacodynamic relationships from four Phase I studies with different schedules of administration of oral topotecan in 99 adult patients with malignant solid tumors refractory to standard forms of chemotherapy were compared. Topotecan was administered as follows: (a) once daily (o.d.) for 5 days every 21 days (29 patients); (b) o.d. for 10 days every 21 days (19 patients); (c) twice daily (b.i.d.) for 10 days every 21 days (20 patients); and (d) b.i.d. for 21 days every 28 days (31 patients). Pharmacokinetic analysis was performed in 55 patients using a validated high-performance liquid chromatographic assay and noncompartmental pharmacokinetic methods. Totals of 109, 48, 64, and 59 courses were given, respectively. Dose-limiting toxicity consisted of granulocytopenia for the o.d. x 5-day dosage, a combination of myelosuppression and diarrhea in both of the 10-day schedules, and only diarrhea in the 21-day schedule. Pharmacokinetics revealed a substantial variation of the area under curve (AUC) of topotecan lactone in all of the dose schedules with a mean intrapatient variation of 25.4 +/- 31.0% (o.d. x 5), 34.5 +/- 25.0% (o.d. x 10), 96.5 +/- 70.1% (b.i.d. x 10), and 59.5 +/- 51.0% (b.i.d. x 21). Significant correlations were observed between myelotoxicity parameters and AUC(t) day 1 and AUC(t) per course of topotecan lactone. In all of the studies, similar sigmoidal relationships could be established between AUC(t) per course and the percentage decrease of WBCs. At maximum-tolerated dose level, no significant difference in AUC(t) per course was found [AUC(t) per course was 107.4 +/- 33.7 ng x h/ml (o.d. x 5), 145.3 +/- 23.8 ng x h/ml (o.d. x 10), 100.0 +/- 41.5 ng x h/ml (b.i.d. x 10), and 164.9 +/- 92.2 ng x h/ml (b.i.d. x 21), respectively.] For oral topotecan, the schedule rather than the AUC(t)-per-course seemed to be related to the type of toxicity. Prolonged oral administration resulted in intestinal side effects as a dose-limiting toxicity, and short-term administration resulted in granulocytopenia. On the basis of this pharmacokinetic study, no schedule preference could be expressed, but based on patient convenience, administration once daily for 5 days could be favored.

Disposition of Cremophor EL in humans limits the potential for modulation of the multidrug resistance phenotype in vivo

The purpose of the present study was to characterize the distribution and elimination kinetics of the paclitaxel vehicle Cremophor EL (CrEL), a polyoxyethylated castor oil that can modulate P-glycoprotein-mediated multidrug resistance in vitro. The pharmacokinetics of CrEL were studied using noncompartmental models in 23 patients with histological proof of malignant solid tumors, receiving paclitaxel as a 3-h i.v. infusion at dose levels ranging from 100-225 mg/m2 (corresponding to CrEL doses of 8.33-18.8 ml/m2). Serial plasma samples were obtained before and up to 72 h after drug administration, and were analyzed for the presence of CrEL by a novel colorimetric dye-binding microassay. The area under the plasma concentration versus time curves and the peak plasma levels of CrEL increased from 253+/-36.8 (mean+/-SD) to 680+/- 180 microl.h/ml, and from 3.40+/-0.10 to 6.58+/-0.52 microl/ml, respectively, consistent with linear pharmacokinetics. Disappearance of CrEL from the central plasma compartment was characterized by a terminal elimination half-life of 84.1+/-20.4 h, resulting in extended persistence of substantial levels even at 1 week after paclitaxel treatment. The observed volume of distribution was extremely low and averaged 3.70+/-0.49 liters/m2, implying that the tumor delivery of CrEL is insignificant. Our results indicate that CrEL is a relatively slow clearance compound and that its distribution is limited to the central plasma compartment. Hence, CrEL is not likely to play a role in reversing P-glycoprotein-mediated multidrug resistance to paclitaxel in vivo.

High prevalence of codon 213Arg-->Stop mutations of the TP53 gene in human ovarian cancer in the southwestern part of The Netherlands

As in many human malignancies, TP53 mutations are the most common genetic alterations in malignant human ovarian tumours. An approach often used in the determination of TP53 status is immunohistochemical staining of the protein. Non-missense mutations, especially those of the null type, causing premature termination codons and resulting in truncated proteins, may often not be detectable by immunohistochemistry. Therefore, current estimates of TP53 alterations in ovarian cancer may be inaccurate. By using polymerase chain reaction-single strand conformation polymorphism analysis and sequencing techniques, we have found a high prevalence of TP53 non-missense mutations in exons 5-8 in ovarian tumour specimens from patients from the southwestern part of The Netherlands. Twenty-nine of 64 tumours showed mutations, of which 10 were non-missense mutations. The majority (9 of 10) of these non-missense mutations, including 7 nonsense mutations and 2 frameshift deletions, were null type mutations and could not be detected by immunohistochemical staining. Five of the 7 nonsense mutations were mutations at codon 213 (Arg-->Stop). The nature of the high prevalence of this nonsense mutation in our series of ovarian carcinomas remains unknown. In addition to the 9 null type mutations, a splice junction mutation was encountered. In conclusion, we have observed a high prevalence (13%) of ovarian tumours with null type mutations in exons 5-8 that did not result in immunostaining. Our data suggest that, especially in ovarian cancer, immunological assessment of TP53 is not an adequate tool to study TP53 alteration. A frequent nonsense mutation at codon 213 in 5 (8%) of 64 tumour specimens represents an important finding.

Oral topotecan given once or twice daily for ten days: a phase I pharmacology study in adult patients with solid tumors

Prolonged exposure to topotecan (TPT) in in vitro experiments and in vivo studies in animals yielded the highest antitumor efficacy. An oral bioavailability of TPT of 32-44% enables convenient prolonged administration. Because of unpredictable diarrhea in the third week of the twice daily (b.i.d.) 21-day schedule of p.o. administered TPT and the finding of optimal down-regulation of topoisomerase I level after 10-14 days in mononuclear peripheral blood cells, a shorter period of administration (10 days) was chosen for Phase I and pharmacological studies of oral administration of TPT. Adult patients with malignant solid tumors that were refractory to standard forms of chemotherapy were entered. Two dose schedules were studied: once daily (o.d.) and b.i.d. administration for 10 days every 3 weeks. TPT o.d. for 10 days was studied at dose levels 1.0, 1.4, and 1.6 mg/m2/day, and dose levels were 0.5, 0.6, 0.7, and 0.8 mg/m2 with the 10-day b.i.d. schedule. Pharmacokinetics were performed on days 1 and 8 of the first course using a validated high-performance liquid chromatographic assay and noncompartmental pharmacokinetic methods. Nineteen patients were entered in the 10-day o.d. schedule, with a total of 48 courses given. Dose-limiting toxicity (DLT) was reached at 1.6 mg/m2/day and consisted of common toxicity criteria (CTC) grade IV thrombocytopenia and CTC grade III diarrhea. The maximum tolerated dose was 1.4 mg/m2/day. In the 10-day b.i.d. administration of TPT, a total of 64 courses were studied in 20 patients. DLT was reached at a dose of 0.8 mg/m2 b.i.d. and consisted of CTC grade IV myelosuppression and CTC grade IV diarrhea. The maximum tolerated dose was 0.7 mg/m2 b.i.d. Nonhematological toxicities with both schedules included mild nausea and vomiting, fatigue, and anorexia. Pharmacokinetics revealed a substantial variation of the area under the plasma concentration-time curve of TPT lactone in both schedules. Significant correlations were observed between the myelotoxicity parameters and the area under the plasma concentration-time curve at day 1 of TPT lactone o.d. and b.i.d. The DLT of 10 daily administrations of oral topotecan every 3 weeks consisted of a combination of myelosuppression and diarrhea for both schedules studied. The recommended doses for Phase II studies are 1.4 mg/m2/day for 10 days for the o.d. administration and 0.7 mg/m2 for the b.i.d. schedule.

Quantitation of Cremophor EL in human plasma samples using a colorimetric dye-binding microassay

This paper describes an analytical procedure for the quantitative determination of the pharmaceutical vehicle Cremophor EL in human plasma samples. The procedure is based on rapid binding of Coomassie brilliant blue G-250 to Cremophor EL following plasma protein precipitation with acetonitrile and analyte extraction with n-butylchloride. The binding of the dye to Cremophor EL causes a shift in the absorption maximum from 465 to 624 nm, which is monitored using an automated microplate-absorbance reader. The assay permits estimation of Cremophor EL concentrations in the range 0.05-1.00% (v/v) in 50 microL of human plasma, with percentage deviation and precision of < or = 12 and < or = 15%, respectively. The assay was subsequently used to measure Cremophor EL concentrations in plasma samples in support of a project to develop a pharmacokinetic model for this compound in patients receiving paclitaxel.

Differential modulation of cisplatin accumulation in leukocytes and tumor cell lines by the paclitaxel vehicle Cremophor EL

BACKGROUND

Several clinical studies have shown that polychemotherapy with the taxanes paclitaxel or docetaxel preceded or followed by cisplatin is associated with important schedule-dependent differences in toxicities, such as leukocytopenia. In general, the pharmacokinetics of both drugs during the combined treatment are unaltered, suggesting that a pharmacodynamic interaction might have occurred.

MATERIALS AND METHODS

In order to gain insight into this pharmacologic interaction, we performed in vitro drug accumulation studies using peripheral blood leukocytes and a panel of tumor and non-malignant cell lines with paclitaxel and docetaxel, as well as with their respective formulation vehicles Cremophor EL and Tween 80.

RESULTS

Our results show a significant reduction in the intracellular cisplatin concentration in leukocytes of up to 42% in the presence of Cremophor EL and Tween 80 as compared to the control. This pharmacodynamic interaction of these surfactants with cisplatin seems to be specific for haematopoietic cells, and does not occur in solid tumor cells.

CONCLUSION

The present data suggest that the pharmaceutical vehicles Cremophor EL and Tween 80 might contribute to the reduced cisplatin-associated myelotoxicity observed in the clinical combination chemotherapy studies with paclitaxel and docetaxel.

Phase II study of weekly 4'-epidoxorubicin in patients with metastatic adenocarcinoma of the cervix: an EORTC Gynaecological Cancer Cooperative Group study

In this study 22 patients with metastatic adenocarcinoma of the cervix were treated with a weekly bolus injection of 4'-epidoxorubicin at a dose of 12 mg/m2. Seventeen patients had received prior radiotherapy, all patients were chemo-naive. Toxicity was generally absent or very mild. One patient had a complete response and 2 patients had a partial response, one was an unconfirmed partial response, giving a response rate of 14%. Six patients had stable disease. The median progression-free survival and overall survival was 2.8 months and 6.1 months, respectively. In conclusion, 4'-epidoxorubicin used at this dosage and schedule has minimal activity in metastatic adenocarcinoma of the cervix.

Phase I and pharmacologic study of docetaxel and cisplatin in patients with advanced solid tumors

PURPOSE

This phase I study was performed to assess the feasibility of the combination of docetaxel and cisplatin and to determine the maximum-tolerated dose (MTD) and the side effects with an emphasis on sequence-dependent side effects.

MATERIALS AND METHODS

Patients who were not pretreated with taxanes or cisplatin derivatives and who had received no more than one prior combination chemotherapy regimen or two single-agent regimens were entered. Treatment consisted of docetaxel given as a 1-hour infusion followed by cisplatin as a 3-hour infusion (schedule A), or cisplatin followed by docetaxel (schedule B). Docetaxel doses ranged from 55 to 100 mg/m2 and cisplatin doses from 50 to 100 mg/m2.

RESULTS

Leukocytopenia and granulocytopenia were common (overall, 90%; grade 3 or 4, 87%), short-lasting, and docetaxel dose-dependent. Infections and neutropenic fever occurred in 10% and 4.5% of courses, respectively. Nonhematologic toxicities were mild to moderate and included alopecia, nausea, vomiting, diarrhea, mucositis, neurotoxicity, fluid retention, and skin and nail toxicity. There were no significant differences in pharmacokinetic parameters between schedules A and B. Tumor responses included one complete response (CR) and nine partial responses (PRs).

CONCLUSION

The dose levels docetaxel 100 mg/m2 plus cisplatin 75 mg/m2 and docetaxel 85 mg/m2 plus cisplatin 100 mg/m2 appeared to be manageable. At these dose levels, the median relative dose-intensity was high and 81% and 88% of all cycles, respectively, could be given at full dose. Schedule A is advocated for further treatment.

Expression of urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 in benign, borderline, malignant primary and metastatic ovarian tumors

Elevated levels of expression of the urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 have shown to be related to poor prognosis in a variety of cancer types. In the present study, cytosolic levels of uPA and PAI-1 were determined with enzyme-linked immunosorbent assays in cytosols prepared from 244 human ovarian tissues of different histological sub-types. Both uPA and PAI-1 were significantly associated with the malignant progression of ovarian tissues; the levels were increased going from normal tissue, via benign and borderline adenomas, to primary and metastatic adenocarcinomas. For the 90 patients (34 early-stage and 56 patients with advanced disease) from whom the primary adenocarcinoma tissues were examined, uPA and PAI-1 levels were evaluated for their association with clinicopathological parameters and with progression-free and overall survival. Neither uPA nor PAI-1 were significantly associated with the age of the patient, FIGO stage, tumor grade, tumor rest, the presence of ascites, or with progression-free or overall survival. On the other hand, age, FIGO stage/tumor rest and the presence of ascites, were significantly related to the length of both progression-free and overall survival in univariate analyses. Tumor grade was of prognostic significance in the analysis for progression-free survival, but not for overall survival. After adjustment for FIGO stage/tumor rest, only age retained its prognostic significance, in the analysis for progression-free survival and in that for overall survival.

Expression of urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 in benign, borderline, malignant primary and metastatic ovarian tumors

Elevated levels of expression of the urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 have shown to be related to poor prognosis in a variety of cancer types. In the present study, cytosolic levels of uPA and PAI-1 were determined with enzyme-linked immunosorbent assays in cytosols prepared from 244 human ovarian tissues of different histological sub-types. Both uPA and PAI-1 were significantly associated with the malignant progression of ovarian tissues; the levels were increased going from normal tissue, via benign and borderline adenomas, to primary and metastatic adenocarcinomas. For the 90 patients (34 early-stage and 56 patients with advanced disease) from whom the primary adenocarcinoma tissues were examined, uPA and PAI-1 levels were evaluated for their association with clinicopathological parameters and with progression-free and overall survival. Neither uPA nor PAI-1 were significantly associated with the age of the patient, FIGO stage, tumor grade, tumor rest, the presence of ascites, or with progression-free or overall survival. On the other hand, age, FIGO stage/tumor rest and the presence of ascites, were significantly related to the length of both progression-free and overall survival in univariate analyses. Tumor grade was of prognostic significance in the analysis for progression-free survival, but not for overall survival. After adjustment for FIGO stage/tumor rest, only age retained its prognostic significance, in the analysis for progression-free survival and in that for overall survival.

Phase II study of a closely spaced ifosfamide--cisplatin schedule with the addition of G-CSF in advanced non-small-cell lung cancer and malignant melanoma

BACKGROUND

Ifosfamide and cisplatin are frequently combined cytotoxic agents. Both have a dose-response relationship. In view of this it appears attractive to study regimens with a higher dose intensity than usual. One way to increase the dose intensity is to shorten intervals between chemotherapy cycles. As bone marrow toxicity is dose limiting in ifosfamide-cisplatin combinations we started a phase II study with both drugs administered every 2 weeks in combination with G-CSF.

PATIENTS AND METHODS

Patients with advanced non-small-cell lung cancer or malignant melanoma were eligible for the study. The treatment consisted of ifosfamide 2 gram/m2/day days 1-3 combined with mesna, and cisplatin 33 mg/m2/day days 1-3, administered in hypertonic saline (3% NaCl). G-CSF was started on day 4 at a dose of 5 micrograms/kg/day and was continued until day 12. The cycles were to be repeated every 2 weeks for a maximum of 6 cycles.

RESULTS

Thirty-two patients were entered in the study; 30 patients were evaluable for response and toxicity. Neutropenia (grade 4 in 16 patients) and thrombocytopenia (grade 4 in 15 patients) were the most common toxicities. Thrombocytopenia incidence and -duration increased per cycle and was the main cause of treatment delays especially after the third cycle. Only 4 patients were able to complete the planned treatment without any delay or dose reduction and reached the intended dose intensity of 3 gram/m2/week of ifosfamide and 50 mg/m2/week of cisplatin. Non haematologic toxicities were generally mild. Out of 22 evaluable patients with non-small cell lung cancer 6 responded (27%; 95% CI: 10%-48%) while only one out of 8 patients with melanoma responded. The median response duration was 26 weeks (range 16-36 weeks).

CONCLUSION

The planned high-dose intensity of ifosfamide and cisplatin could be reached only for the first 2-3 cycles. Haematologic toxicity, especially cumulative thrombocytopenia, necessitated treatment delays jeopardizing the dose intensity. The response rate in non-small-cell lung cancer and melanoma was not superior to what can be expected from more conventional regimens.

Phase II study of a short course of weekly high-dose cisplatin combined with long-term oral etoposide in metastatic malignant melanoma

The results of cytostatic therapy in metastatic melanoma are very disappointing. In phase II studies with high-dose cisplatin regimens, a remarkably high response rate was observed. In a phase I study with a short course of weekly cisplatin, combined with oral etoposide, we were able to reach, in most patients, a cisplatin dose intensity of 60 mg/m2/week. We performed a phase II study with this schedule in metastatic malignant melanoma. 15 consecutive patients were entered in the study. Treatment consisted of cisplatin 70 mg/m2 on days 1, 8, 15 and days 29, 36, 43 combined with oral etoposide 50 mg daily, days 1-15 and days 29-43. Patients with a response or stable disease continued treatment with oral etoposide 50 mg/m2 daily, days 1-21 every 4 weeks. All patients were evaluable for response and toxicity. The majority of the patients received six cycles of cisplatin with the planned cisplatin dose intensity of 60 mg/m2/week. A partial response was observed in 2 patients (13%; 95% confidence interval (CI) 2-44%) of, respectively, 22 and 12 weeks; stable disease was observed in 6 patients. Toxicity consisted mainly of alopecia and bone marrow suppression. 4 patients had tinnitus, one patient had neurotoxicity grade 1. The regimen studied has only limited activity in metastatic melanoma in spite of the high-dose intensity of cisplatin reached with this schedule.

Phase II and pharmacologic study of topotecan administered as a 21-day continuous infusion to patients with colorectal cancer

PURPOSE

Topotecan is a specific inhibitor of topoisomerase I. Preclinical data have indicated that topoisomerase I inhibitors demonstrate more efficacy and have a greater therapeutic index with prolonged continuous exposure. The feasibility of this concept in humans using a 21-day continuous infusion of topotecan has been reported. We conducted a phase II study of this 21-day continuous topotecan administration schedule in patients with locally advanced, unresectable or metastatic colorectal cancer.

PATIENTS AND METHODS

Topotecan, initially applied at a dose of 0.6 mg/m2/d, was administered as a continuous infusion via an ambulatory pump for 21 days repeated every 4 weeks. The starting dose was reduced to 0.5 mg/m2/d, because in five of the first 11 patients, the second course had to be delayed due to prolonged myelosuppression. Forty-two patients entered the study; one patient was ineligible and was excluded from further analyses.

RESULTS

The overall response rate was 10%, with one complete and three partial responses. The median response duration was 7 months (range, 4 to 11). With this schedule, the major toxicity was prolonged cumulative myelosuppression, including a marked inhibition of erythropoiesis. A total transfusion of 250 U of erythrocytes was needed to maintain a hemoglobin level greater than 6.0 mmol/L. Other side effects were mild, and included alopecia (47%), periodic nausea (40%)/vomiting (22%), and fatigue (16%). Pharmacokinetic evaluation showed a mean steady-state plasma concentration (Css) of topotecan of 0.62 ng/mL (range, 0.33 to 1.1), with a significant relationship between the Css of topotecan and common cytotoxicity criteria (CTC) grade of leukocytopenia.

CONCLUSION

Topotecan administered as a 21-day continuous infusion exerts minor activity as single-agent therapy in patients with metastatic colorectal cancer.

Relationship between the exposure to cisplatin, DNA-adduct formation in leucocytes and tumour response in patients with solid tumours

The study was designed to investigate possible relationships between tumour response and exposure to cisplatin (area under the curve of unbound cisplatin in plasma, AUC) and DNA-adduct formation in leucocytes (WBC) in patients with solid tumours. Patients were treated with six weekly courses of cisplatin at a dose of 70 or 80 mg m-2. The AUC was determined during the first course and DNA-adduct levels in WBC during all courses at baseline, 1 h (A(max)) and 15 h after a 3 h infusion of cisplatin. The area under the DNA-adduct-time curve (AUA) was calculated. The tumour response was determined after six courses. Forty-five evaluable patients received 237 courses of cisplatin. Sixteen patients with head and neck cancer received a dose of 80 mg m-2 and 29 with various other tumour types received 70 mg m-2 plus daily 50 mg oral etoposide. There were 20 responders (partial and complete) and 25 non-responders (stable and progressive disease). The AUC was highly variable (mean +/- s.d. = 2.48 +/- 0.51 micrograms h-1 ml-1; range 1.10-3.82) and was closely correlated with the AUA (r = 0.78, P < 0.0001) and A(max) (r = 0.73, P < 0.0001). The AUC, AUA and A(max) were significantly higher in responders than in non-responders in the total population (P < 0.0001) and in the two subgroups treated at 70 or 80 mg m-2. In logistic regression analysis AUC, AUA and A(max) were important predictors of response. The magnitude of exposure to cisplatin is, through DNA-adduct formation, the major determinant of the response rate in this population. Hence, individualised dosing of cisplatin using AUC or DNA-adducts should lead to increased response rates.

Phase II study of a short course of weekly high-dose cisplatin combined with long-term oral etoposide in metastatic colorectal cancer

In a phase I study of weekly administered cisplatin combined with oral etoposide, we observed a partial response in 4 out of 11 patients with metastatic colorectal cancer. Subsequently, we performed a phase II study to investigate the activity of this combination as first-line treatment in this disease. Fourteen patients with metastatic colorectal cancer were enrolled in this study. Treatment consisted of cisplatin, administered in 3% sodium chloride, at a dose of 70 mg m-2 on days 1, 8 and 15 and days 29, 36 and 43 combined with oral etoposide 50 mg absolute dose daily on days 1-15 of both courses. Patients with stable disease or better continued treatment with etoposide 50 mg m-2 orally on days 1-21 every 28 days. A partial response was observed in two patients with liver metastases (14%; 95% confidence limits 2-42%) for 30 and 32 weeks. Five patients had stable disease. Toxicity consisted mainly of anaemia, leucocytopenia, nausea and vomiting. Tinnitus was reported by six patients. The activity of the combination cisplatin-oral etoposide in the schedule is only minimal in metastatic colorectal cancer.

Analysis of cumulative probabilities shows that the efficacy of 5HT3 antagonist prophylaxis is not maintained

PURPOSE

Several investigators have reported that the efficacy of 5HT3 receptor antagonists is maintained over repeated cycles of chemotherapy. These investigators presented conditional probabilities of protection. Because conditional analyses by definition only include patients with protection in previous cycles, the results are flattered.

PATIENTS AND METHODS

We applied a novel statistical approach to investigate whether the efficacy of the 5HT3 receptor antagonist ICS 205-930 (tropisetron) is maintained over repeated cycles of weekly high-dose cisplatin. Overall protection was determined based on cumulative probabilities with the Kaplan-Meier method. Complete protection was calculated with a three state model for transitional probabilities. Eighty-three patients were studied.

RESULTS

Over six consecutive cycles, protection against both acute and delayed emesis decreased significantly. The initial complete and overall protection rates against acute emesis of 71% and 95%, respectively, decreased to 43% and 72% in the sixth cycle of chemotherapy. Similarly, the protection rates of 31% and 68% against delayed emesis decreased to 6% and 40%, respectively.

CONCLUSION

We conclude that overall and complete long-term protection is more accurately measured by cumulative probabilities than with a method that is based on conditional probabilities. Our statistical approach shows that the efficacy of 5HT3 antagonists is not maintained.

Docetaxel and paclitaxel inhibit DNA-adduct formation and intracellular accumulation of cisplatin in human leukocytes

The purpose of this study was to determine the mechanism of the pharmacodynamic interaction between docetaxel/paclitaxel and cisplatin. Cisplatin-induced DNA-adducts and cisplatin accumulation were quantitated in peripheral blood leukocytes (WBC). The WBC were obtained from patients treated with docetaxel or paclitaxel in phase I/II studies and were incubated in vitro with cisplatin. In addition, blank whole-blood samples were obtained from patients and healthy subjects and incubated in intro with cisplatin or docetaxel/paclitaxel and cisplatin. The cisplatin-induced DNA-adduct levels measured in WBC after treatment with docetaxel or paclitaxel were significantly lower than those determined in non-pretreated WBC. Docetaxel and paclitaxel reduced the intracellular accumulation of cisplatin in WBC by 46-47%. If the pharmacodynamic interaction between docetaxel/paclitaxel and cisplatin also occurs in other normal tissues such as bone marrow, it may well contribute to the sequence dependent toxicity that has been observed in clinical studies.

Phase II study of a short course of weekly high-dose cisplatin combined with long-term oral etoposide in pleural mesothelioma

BACKGROUND

In a previous phase II study with a dose-intensive weekly cisplatin schedule for six cycles, we observed a partial response in 5 of 14 patients with pleural mesothelioma. However, response duration was short (median 6 months). Since oral etoposide may theoretically be synergistic to cisplatin, we performed a phase II study with the combination of both drugs.

PATIENTS AND METHODS

Twenty-five chemo-naive patients with pleural mesothelioma were treated with cisplatin 70 mg/m2 days 1-8-15 and days 29-36-43 in combination with oral etoposide 50 mg days 1-15 and days 29-43. Patients with stable disease, or better, continued treatment with oral etoposide 50 mg/m2/day days 1-21 every 28 days RESULTS All patients were evaluable for response and toxicity. Complete response was observed in one patient and partial responses in 5 patients (RR% 24%; 95% Cl: 10%-45%) for a median duration of 30 weeks. Twelve patients had stable disease. The response status never improved during maintenance treatment with oral etoposide. Most patients tolerated the regimen very well. Toxicity was manly haematologic with leukocytopenia causing treatment delays in 8 patients. Ototoxicity grade 1 or 2 was observed in 8 patients, neurotoxicity grade 1 in 9 patients and nephrotoxicity grade 1 in 1 patient.

CONCLUSION

Frequently administered cisplatin in combination with oral etoposide has a moderate but definite activity in pleural mesothelioma.

Effect of an ACTH(4-9) analogue on cisplatin neuropathy of longstanding duration: a phase II study

The efficacy of Org 2766, an ACTH(4-9) analogue, on the recovery of cisplatin neuropathy of longstanding duration was investigated in a phase II study. Twenty-two patients were treated with Org 2766 during a period of 4 months and vibration perception threshold (VPT) and sum scores for neuropathic symptoms and signs were compared with pre-treatment values. No change in VPT could be detected. Although there was a small improvement of clinical measures for neuropathy, no clear evidence for repair could be obtained. These results indicate no beneficial effect of Org 2766 on recovery of a longstanding cisplatin neuropathy.

The effect of debulking surgery after induction chemotherapy on the prognosis in advanced epithelial ovarian cancer. Gynecological Cancer Cooperative Group of the European Organization for Research and Treatment of Cancer

BACKGROUND

Although the value of primary cytoreductive surgery for epithelial ovarian cancer is beyond doubt, the value of debulking surgery after induction chemotherapy has not yet been defined. In this randomized study we investigated the effect on survival of debulking surgery.

METHODS

Eligible patients had residual lesions measuring more than 1 cm in diameter after primary surgery. After three cycles of cyclophosphamide and cisplatin, these patients were randomly assigned to undergo either debulking surgery or no surgery, followed by further cycles of cyclophosphamide and cisplatin. The study end points were progression-free and overall survival. At surgery 65 percent of the patients had lesions measuring more than 1 cm. In 45 percent of this group, the lesions were reduced surgically to less than 1 cm.

RESULTS

Of the 319 patients who underwent randomization, 278 could be evaluated (140 patients who underwent surgery and 138 patients who did not). Progression-free and overall survival were both significantly longer in the group that underwent surgery (P = 0.01). The difference in median survival was six months. The survival rate at two years was 56 percent for the group that underwent surgery and 46 percent for the group that did not. In the multivariate analysis, debulking surgery was an independent prognostic factor (P = 0.012). Overall, after adjustment for all other prognostic factors, surgery reduced the risk of death by 33 percent (95 percent confidence interval, 10 to 50 percent; P = 0.008). Surgery was not associated with death or severe morbidity.

CONCLUSIONS

Debulking surgery significantly lengthened progression-free and overall survival. The risk of death was reduced by one third, after adjustment for a variety of prognostic factors.

Current sample handling methods for measurement of platinum-DNA adducts in leucocytes in man lead to discrepant results in DNA adduct levels and DNA repair

DNA adduct levels were measured with atomic spectroscopy in white blood cells (WBCs) from patients with solid tumours who were treated with six weekly courses of cisplatin. In 21 patients (I) the WBCs were collected after thawing frozen whole-blood samples according to a previously described method. In 32 other patients (II) WBCs were collected immediately after blood sample collection. The two methods for WBC collection were also compared in vitro. The maximal DNA adduct levels in vivo after the first course were in I 2.48 +/- 1.14 and in II 1.28 +/- 0.40 pg of platinum per microgram of DNA (P < 0.0001). The DNA 'repair' in the first course (DNA adduct level at the end of the infusion minus the level 15 h post infusion) was in I 40% +/- 29% and in II 18% +/- 29% (P = 0.009). These differences were consistent in all measured courses. In vitro, the DNA adduct levels in the freshly prepared WBCs were significantly lower at 0, 1 and 4, but not 24 h, after start of the incubation with cisplatin than in the WBCs collected after freezing and thawing the blood sample. The same experiment with carboplatin in vitro also resulted in significantly lower adducts in freshly isolated WBCs. The higher DNA adduct levels and DNA 'repair' in I are caused by remaining unbound cisplatin in the sample tubes, which can form DNA adducts ex vivo. The same results in vivo can be anticipated when carboplatin is used.

Phase I study of weekly high-dose cisplatin combined with long-term oral etoposide in advanced solid tumors

BACKGROUND

In a previous phase I study we showed that single-agent cisplatin can be given weekly for six weeks at a dose of 80 mg/m2/wk. It has been suggested that etoposide has synergistic activity with cisplatin and the drug can be given orally continuously. We therefore performed a phase I study with weekly cisplatin combined with oral etoposide.

PATIENTS AND METHODS

Nineteen patients with metastases of a solid tumor were entered in the study. Cisplatin was administered in hypertonic saline (NaCl 3%). Etoposide was administered as 50-mg capsules.

RESULTS

The starting dose was cisplatin weekly at a dose of 70 mg/m2 for six weeks combined with daily oral etoposide at a dose of 50 mg. At the maximum tolerable dose of cisplatin 75 mg/m2/wk and etoposide 50 mg/m2 daily, leukocytopenia and thrombocytopenia were dose-limiting toxic effects which resulted in frequent treatment delays. Other toxicities were mild. Finally, a dose of cisplatin 70 mg/m2/wk weeks 1-2-3 and weeks 5-6-7 in combination with etoposide 50 mg orally days 1-15 and days 29-43 combined a high median cisplatin dose intensity of 52.5 mg/m2/wk with a good patient tolerance.

CONCLUSION

It is feasible to administer frequently dosed cisplatin in combination with oral etoposide. Leukocytopenia and thrombocytopenia are dose-limiting toxicities. The schedule will be explored further in phase II studies.

Neurotoxicity is not enhanced by increased dose intensities of cisplatin administration

It is uncertain whether intensive dosing schedules of cisplatin, intended to attain a higher anti-tumour efficacy, alter the severity of cisplatin-induced neuropathy. We assessed the development of neuropathy in three groups of patients treated with cisplatin in different dosing schedules. The severity of neuropathy was determined by measurement of the vibration perception threshold (VPT) before treatment and during follow-up for 2-12 months after the last cycle. 66 patients were treated with an intensive weekly regimen of doses varying from 70 to 85 mg/m2 in 1 day (trial A), 21 patients with a 3-weekly combination chemotherapy containing cisplatin 75 mg/m2 in 1 day (trial B) and 20 patients with a 3-weekly regimen containing cisplatin 20 mg/m2 for 5 consecutive days (trial C). The mean dose intensity achieved was 59 mg/m2/week in trial A, 21 mg/m2/week in trial B and 33 mg/m2/week in trial C. The maximum post-treatment VPT correlated significantly with pretreatment VPT (P < 0.001) and with the cumulative dose of cisplatin (P < 0.001). Following correction for these two variables, the maximum posttreatment VPT did not show a statistically significant association with dose intensity. These results suggest that neuropathy is not related to dose intensity of cisplatin. This implies that treatment with more intensive dosing schedules, employing equal cumulative doses of cisplatin, does not result in a concomitant increase in neurotoxicity within a cumulative dose range of 280-675 mg/m2.

European-Canadian randomized trial of paclitaxel in relapsed ovarian cancer: high-dose versus low-dose and long versus short infusion

PURPOSE

Taxol (paclitaxel; Bristol-Myers Squibb, Wallingford, CT) is a new anticancer agent with activity in a number of human tumors, including epithelial ovarian cancer. In nonrandomized trials, doses studied have ranged from 135 mg/m2 to 250 mg/m2 administered over 24 hours with premedication to avoid hypersensitivity reactions (HSRs). This study addressed two questions: the dose-response relationship of Taxol in relapsed ovarian cancer and the safety of a short infusion given with premedication.

METHODS

Women with platinum-pretreated epithelial ovarian cancer and measurable recurrent disease were randomized in a bifactorial design to receive either 175 or 135 mg/m2 of Taxol over either 24 or 3 hours. Major end points were the frequency of significant HSRs and objective response rate. Secondary end points were progression-free and overall survival.

RESULTS

Of 407 patients randomized, 391 were eligible and 382 assessable for response. Analysis was performed according to the bifactorial design. Severe HSRs were rare (1.5% patients) and were not affected by either dose or schedule. Response was slightly higher at the 175-mg/m2 dose (20%) than at 135 mg/m2 (15%), but this was not statistically significant (P = .2). However, progression-free survival was significantly longer in the high-dose group (19 v 14 weeks; P = .02). Significantly more neutropenia was seen when Taxol was administered as a 24-hour infusion. Response rates were similar in the 24- and 3-hour groups (19% and 16%, respectively; P = .6). No survival differences were noted.

CONCLUSION

The 3-hour infusion of Taxol is safe when given with premedication and is associated with less neutropenia. There is a modest dose effect with longer time to progression at 175 mg/m2. The observation that longer infusion produces more myelosuppression but does not yield higher response rates should lead to further studies to determine the optimal dose and schedule of this interesting new agent.

Phase II study of prolonged oral etoposide in patients with ovarian cancer refractory to or relapsing within 12 months after platinum-containing chemotherapy

PATIENTS AND METHODS

Twenty-eight patients with ovarian cancer refractory to or relapsing within 12 months after cisplatin-containing chemotherapy were treated with etoposide 50 mg/m2 daily for 21 days, followed by a 7-day break.

RESULTS

Of 25 evaluable patients, 4 achieved partial responses (16%, 95% confidence interval 5%-36%) of 4, 4, 7, and 10 months' duration. The platinum treatment-free intervals for these patients were 2, 9, 7, and 10 months, respectively. Etoposide in this schedule was generally well tolerated, with myelosuppression as the major toxicity, resulting in a median dose intensity over all cycles of 83% (range 47%-100%).

CONCLUSIONS

Prolonged oral etoposide is moderately active both in relapsed and platinum-refractory ovarian cancer, and a schedule of 50 mg/m2 days 1-21, every 4 weeks is fairly well tolerated in this usually heavily pretreated and elderly patient population.

Phase I and pharmacologic study of the novel indoloquinone bioreductive alkylating cytotoxic drug E09

BACKGROUND

A novel bioreductive alkylating indoloquinone compound, E09 [3-hydroxy-5-aziridinyl-1-methyl-2-(1H-indole-4,7-indione)- prop-F128b-en-alpha-ol], has been shown to have distinct antitumor activity against solid tumors, excellent activity under hypoxic conditions, but no notable bone marrow toxicity in preclinical models.

PURPOSE

A phase I study was carried out to determine the toxicity, maximum tolerated dose (MTD), pharmacology, and antitumor response of E09.

METHODS

E09 was administered as a 5-minute intravenous infusion once every 3 weeks to 32 patients with solid tumors. The starting dose of 2.7 mg/m2 was one tenth of the mouse equivalent of lethal dose to 10% of animals (MELD10). Dose was escalated by 100% until the area under the curve (AUC) at the MELD10 was reached, following a Fibonacci-like schedule. The pharmacokinetics of E09 and its metabolite E05A with an open aziridine ring was determined using a new high-pressure liquid chromatographic method and noncompartmental calculation of kinetic parameters. The sigmoid Emax model was used to fit pharmacokinetic parameters to toxicity. The renal function and proteinuria were quantitated and were further evaluated by determining renal clearance ratios of immunoglobulin G (IgG) to albumin and pancreatic amylase to salivary amylase.

RESULTS

The 32 patients were treated with a total of 85 assessable courses of E09. The dose-limiting toxicity was proteinuria, which was accompanied by sodium and water retention. All symptoms were reversible on day 15 except in two patients, who developed acute renal failure. The ratios of IgG to albumin and pancreatic amylase to salivary amylase suggested a loss of glomerular negative charge consistent with a minimal change glomerulopathy. The pharmacokinetics of E09 showed its rapid elimination from the central compartment but with wide interpatient variation in the overall disposition of the drug. Total plasma clearance of E09 ranged from 3.2 to 24 L/min. The AUC of E09 was linearly related to the administered dose. The relationship between the AUC and proteinuria was best fitted by the sigmoid Emax model (r = .98). In two patients with adenocarcinoma of unknown primary site and in a third patient with bile duct cancer, a partial response was observed.

CONCLUSIONS

The MTD of E09 was determined to be 27 mg/m2. The standard approach of drug administration is considered unsuitable because of potential renal toxicity and wide variability in the pharmacokinetics of E09. Individual dose adjustments based on plasma concentration measurements are recommended to combine maximally achievable exposure with tolerable toxicity.

Ki-67 staining in benign, borderline, malignant primary and metastatic ovarian tumors: correlation with steroid receptors, epidermal-growth-factor receptor and cathepsin D

Ki-67 immunoreactivity was studied in relation to immunohistochemically assessed expression of epidermal-growth-factor receptor (EGFR), estrogen receptor (ER) progesterone receptor (PgR) and cytosolic levels of cathepsin D in advanced human ovarian adenocarcinomas, borderline and benign cystadenomas and normal ovaries. A significantly higher number of Ki-67-positive cells were found in metastatic tumors vs. primary adenocarcinomas and in the total group of adenocarcinomas vs. benign/borderline cystadenomas. Cathepsin-D levels were also significantly higher in metastatic tumors than in primary adenocarcinomas, which in turn presented higher levels than were found in normal ovaries. However, no significant difference was observed between cathepsin-D levels in malignant adenocarcinomas and borderline/benign cystadenomas. Immunohistochemically assessed expression of ER and PgR was detected in variable percentages of epithelial tumor cells, and stromal cells were occasionally positive as well. In the group of primary adenocarcinomas, 46% were ER-positive and 34% were PgR-positive, although there was no significant difference between primary and metastatic lesions with respect to ER or PgR expression. Concordance between immunohistochemically assessed ER or PgR data and cytosolic ER and PgR levels measured with enzyme immunoassay was relatively low. EGFR, immunohistochemically assessed with MAb-EGFRI, was positive in 76% of the primary and in 78% of the metastatic adenocarcinomas. A strong positive association was detected between ER and PgR, and EGFR was observed to present a weak positive correlation with Ki-67 and ER. Cathepsin-D levels were not found to be significantly correlated with the expression of ER, PgR, EGFR or Ki-67.