Prediction of successful revision surgery for mesh-related complaints after inguinal hernia and pelvic organ prolapse repair.

PURPOSE: With this retrospective case series, we aim to identify predictors for reduction of pain after mesh revision surgery in patients operated for inguinal hernia or pelvic organ prolapse with a polypropylene implant. Identifying these predictors may aid surgeons to counsel patients and select appropriate candidates for mesh revision surgery. METHODS: Clinical records before and after mesh revision surgery from 221 patients with chronic postoperative inguinal pain (CPIP) and 59 patients with pain after pelvic organ prolapse (POP) surgery were collected at two experienced tertiary referral centers. Primary outcome was patient reported improvement of pain after revision surgery. A multivariable logistic regression model was used to specify predictors for pain reduction. RESULTS: The multivariable logistic regression was performed for each patient group separately. Patients with CPIP had higher chances of improvement of pain when time between mesh placement and mesh revision surgery was longer, with an OR of 1.19 per year. A turning point in chances of risks and benefits was demonstrated at 70 months, with improved outcomes for patients with revision surgery ≥ 70 months (OR 2.86). For POP patients, no statistically significant predictors for reduction of pain after (partial) removal surgery could be identified. CONCLUSION: A longer duration of at least 70 months between implantation of inguinal mesh and revision surgery seems to give a higher chance on improvement of pain. Caregivers should not avoid surgery based on a longer duration of symptoms when an association between symptoms and the location of the mesh is found.

[The reliability of Delta-T]. / De betrouwbaarheid van Delta-T.

BACKGROUND: In Dutch mental health care there is an ongoing debate about the benefits of rom and utility of benchmarking. Opinions vary regarding the reliability and validity of performance indicators.
AIM: Investigation of the reliability of the main indicator of Foundation Benchmark Mental Health Care (sbg), Delta-T, the indicator of treatment outcome.
METHOD: The reliability was established with two indices: the intraclass correlation coefficient (icc) for the agreement between repeated assessments of average treatment outcome and the consistency in rank order of mental health care providers over time.
RESULTS: The reliability of Delta-T proved to be excellent.
CONCLUSION: Reliability is a basic requirement, but only the first step in establishing the utility of Delta-T. Further investigation of its validity is ongoing, especially on how robust treatment outcome is for bias due to instrumentation, selection, and confounding by casemix composition. Ultimately, the usefulness of treatment outcome as indicator of quality of care needs to be demonstrated in practice.

Improved survival for sequentially as opposed to concurrently delivered neoadjuvant chemotherapy in non-metastatic breast cancer.

PURPOSE: The INTENS study was designed to determine whether delivering neoadjuvant chemotherapy at a higher dose in a shorter period of time improves outcome of breast cancer patients. METHODS: Women with newly diagnosed breast cancer were randomly assigned to neoadjuvant chemotherapy consisting of four cycles of doxorubicin and cyclophosphamide followed by four cycles of docetaxel (AC 60/600-T 100 mg/m2) or six cycles of TAC as triplet chemotherapy (75/50/500 mg/m2) every 3 weeks. The primary outcome was the pathologic complete response (pCR), with disease-free and overall survival as secondary endpoints. RESULTS: In total, 201 patients were included. The pCR rates were 28% for patients treated with AC-T and 19% for patients treated with TAC, with an odds ratio of 1.60 (95% CI 0.90-3.21). With a median follow-up of 6 years (range 0.04-8.41 years), the five-year disease-free survival was 81% for patients treated with sequentially AC-T and 71% for patients treated with concurrent triplet TAC chemotherapy with a stratified hazard ratio (HR) of 0.50 (95% CI 0.29-0.86). Five-year overall survival was 84% versus 76%, respectively, with a stratified HR of 0.55 (95% CI 0.29-1.03). CONCLUSIONS: No differences were observed between the two treatment arms with respect to pCR rate, but the sequentially delivered chemotherapy outperformed the triplet combination chemotherapy in terms of survival, despite a lower cumulative dose per agent. GOV nr NCT00314977.

Does Internet-based guided-self-help for depression cause harm? An individual participant data meta-analysis on deterioration rates and its moderators in randomized controlled trials.

BACKGROUND: Almost nothing is known about the potential negative effects of Internet-based psychological treatments for depression. This study aims at investigating deterioration and its moderators within randomized trials on Internet-based guided self-help for adult depression, using an individual patient data meta-analyses (IPDMA) approach. METHOD: Studies were identified through systematic searches (PubMed, PsycINFO, EMBASE, Cochrane Library). Deterioration in participants was defined as a significant symptom increase according to the reliable change index (i.e. 7.68 points in the CES-D; 7.63 points in the BDI). Two-step IPDMA procedures, with a random-effects model were used to pool data. RESULTS: A total of 18 studies (21 comparisons, 2079 participants) contributed data to the analysis. The risk for a reliable deterioration from baseline to post-treatment was significantly lower in the intervention v. control conditions (3.36 v. 7.60; relative risk 0.47, 95% confidence interval 0.29-0.75). Education moderated effects on deterioration, with patients with low education displaying a higher risk for deterioration than patients with higher education. Deterioration rates for patients with low education did not differ statistically significantly between intervention and control groups. The benefit-risk ratio for patients with low education indicated that 9.38 patients achieve a treatment response for each patient experiencing a symptom deterioration. CONCLUSIONS: Internet-based guided self-help is associated with a mean reduced risk for a symptom deterioration compared to controls. Treatment and symptom progress of patients with low education should be closely monitored, as some patients might face an increased risk for symptom deterioration. Future studies should examine predictors of deterioration in patients with low education.

Addition of zoledronic acid to neoadjuvant chemotherapy does not enhance tumor response in patients with HER2-negative stage II/III breast cancer: the NEOZOTAC trial (BOOG 2010-01).

BACKGROUND: The role of zoledronic acid (ZA) when added to the neoadjuvant treatment of breast cancer (BC) in enhancing the clinical and pathological response of tumors is unclear. The effect of ZA on the antitumor effect of neoadjuvant chemotherapy has not prospectively been studied before. PATIENTS AND METHODS: NEOZOTAC is a national, multicenter, randomized study comparing the efficacy of TAC (docetaxel, adriamycin and cyclophosphamide i.v.) followed by granulocyte colony-stimulating factor on day 2 with or without ZA 4 mg i.v. q 3 weeks inpatients withstage II/III, HER2-negative BC. We present data on the pathological complete response (pCR in breast and axilla), on clinical response using MRI, and toxicity. Post hoc subgroup analyses were undertaken to address the predictive value of menopausal status. RESULTS: Addition of ZA to chemotherapy did not improve pCR rates (13.2% for TAC+ZA versus 13.3% for TAC). Postmenopausal women (N = 96) had a numerical benefit from ZA treatment (pCR 14.0% for TAC+ZA versus 8.7% for TAC, P = 0.42). Clinical objective response did not differ between treatment arms (72.9% versus 73.7%). There was no difference in grade III/IV toxicity between treatment arms. CONCLUSIONS: Addition of ZA to neoadjuvant chemotherapy did not improve pathological or clinical response to chemotherapy. Further investigations are warranted in postmenopausal women with BC, since this subgroup might benefit from ZA treatment.

Panitumumab monotherapy as a second-line treatment in metastasised colorectal cancer: a single centre experience.

AIMS: To report our clinical experience of panitumumab monotherapy as a second-line treatment for patients with metastatic colorectal cancer (mCRC). MATERIALS AND METHODS: This retrospective, descriptive study included a series of consecutive patients receiving panitumumab monotherapy (6 mg/kg 2 weekly) at a single centre in the Netherlands between June 2009 and November 2011. All patients had wild-type KRAS tumours, had progressed during first-line fluoropyrimidine-based therapy and were not candidates for, or refused, standard second-line therapy (usually irinotecan in the Netherlands). Prophylactic medication was given for epidermal growth factor receptor inhibitor-associated skin toxicities. RESULTS: Thirty-one patients were treated during this period. The most commonly administered first-line mCRC regimen was capecitabine/oxaliplatin/bevacizumab (18/31 patients; 58.1%). Patients received a mean of 7.9 (range 1-18) panitumumab cycles. The median progression-free survival was 3.4 (95% confidence interval 2.4, 4.4) months. The median overall survival estimates were 11.4 (95% confidence interval 1.2, 21.6) months from the initiation of panitumumab monotherapy. Ten patients experienced partial responses according to Response Evaluation Criteria In Solid Tumors (RECIST; objective response rate: 32.3%); disease was controlled (objective response or stable disease) in 15 patients (48.4%). Carcinoembryonic antigen (CEA) responses (two consecutive ≥10% decreases from baseline) occurred in 11/29 patients (37.9%); all of whom had >50% decreases in CEA levels. All patients with an objective response at week 12 had CEA reductions at weeks 6 and 12. The only adverse events were grade 1/2 skin toxicities (61.3%) and gastrointestinal complaints (6.5%); three other patients (9.7%) experienced both skin and gastrointestinal complaints. CONCLUSION: Panitumumab monotherapy seems to be a safe and active second-line treatment for patients with wild-type KRAS mCRC, with activity in line with that seen for irinotecan monotherapy, but with less toxicity. CEA may provide a useful early indicator of response to panitumumab.

Predictors and moderators of response to internet-delivered Interpersonal Psychotherapy and Cognitive Behavior Therapy for depression.

BACKGROUND: By identifying which predictors and moderators lead to beneficial outcomes, accurate selection of the best initial treatment will have significant benefits for depressed individuals. METHOD: An automated, fully self-guided randomized controlled internet-delivered noninferiority trial was conducted comparing two new interventions (Interpersonal Psychotherapy [IPT; n=620] and Cognitive Behavioral Therapy [CBT; n=610]) to an active control intervention (MoodGYM; n=613) over a period of 4 weeks to spontaneous visitors of an internet-delivered therapy website (e-couch). A range of putative predictors and moderators (socio-demographic characteristics [age, gender, marital status, education level], clinical characteristics [depression/anxiety symptoms, disability, quality of life, medication use], skills [mastery and dysfunctional attitudes] and treatment preference) were assessed using internet-delivered self-report measures at baseline and immediately following treatment and at six months follow-up. Analyses were conducted using Mixed Model Repeated Measures (MMRM). RESULTS: Female gender, lower mastery and lower dysfunctional attitudes predicted better outcome at post-test and/or follow-up regardless of intervention. No overall differential effects for condition on depression as a function of outcome were found. However, based on time-specific estimates, a significant interaction effect of age was found. For younger people, internet-delivered IPT may be the preferred treatment choice, whereas older participants derive more benefits from internet-delivered CBT programs. LIMITATIONS: Although the sample of participants was large, power to detect moderator effects was still lacking. CONCLUSIONS: Different e-mental health programs may be more beneficial for specific age groups. The findings raise important possibilities for increasing depression treatment effectiveness and improving clinical practice guidelines for depression treatment of different age groups.

Doxorubicin/cyclophosphamide with concurrent versus sequential docetaxel as neoadjuvant treatment in patients with breast cancer.

BACKGROUND: This study was designed to determine whether delivering neo-adjuvant chemotherapy at a higher dose in a shorter period of time improves outcome of breast cancer patients. PATIENTS AND METHODS: Women with newly diagnosed breast cancer were randomly assigned to neoadjuvant chemotherapy of four cycles of doxorubicin and cyclophosphamide followed by four cycles of docetaxel (AC 60/600 - T 100 mg/m(2)) or six cycles of TAC (75/50/500 mg/m(2)) every 3 weeks. The primary endpoint was the pathologic complete response (pCR) rate, defined as no invasive tumour present in the breast. RESULTS: In total, 201 patients were included. Baseline characteristics were well balanced. AC-T resulted in pCR in 21% and TAC in 16% of patients (odds ratio 1.44 (95% confidence interval (CI) 0.67-3.10). AC-T without primary granulocyte-colony stimulating factor (G-CSF) prophylaxis was associated with more febrile neutropenia compared to TAC with primary G-CSF prophylaxis (23% versus 9%), and with more grade 3/4 sensory neuropathy (5% versus 0%). CONCLUSIONS: With a higher cumulative dose for the concurrent arm, no differences were observed between the two treatment arms with respect to pCR rate. The differential toxicity profile could partly be explained by different use of primary G-CSF prophylaxis.

Identification of residual breast tumour localization after neo-adjuvant chemotherapy using a radioactive 125 Iodine seed.

INTRODUCTION: The use of neo-adjuvant chemotherapy has increased in the treatment of loco-regionally advanced primarily operable breast cancer. As a result of improved neo-adjuvant chemotherapy regimes the number of clinical as well as radiological responses have increased. In case of a complete response it is difficult to identify residual disease and to perform an adequate radical breast-conserving surgery. Therefore localization of the original tumour bed is mandatory. In this study we propose a novel technique with a seed containing radioactive 125 Iodine ((125)I). The (125)I has a half-time of 60 days and is therefore still recognisable with a gamma probe after admittance of several courses of neo-adjuvant chemotherapy. MATERIAL AND METHODS: In the period from July 2003 and November 2008, 47 consecutive patients had successful (125)I seed localization of a breast tumour before starting neo-adjuvant chemotherapy. RESULTS: The overall clinical response rate to neo-adjuvant chemotherapy was 100%. Complete clinical response occurred in 34 patients, partial clinical response occurred in 13 patients. Complete radiological response occurred in 18 patients, partial radiological response occurred in 29 patients. The initial surgical treatment consisted of breast-conserving surgery for all 47 patients, after a mean of 170 days (range: 70-220) after (125)I seed localization. In 19 patients pathology revealed no residual tumour, 23 patients showed a partial response. Only 3 lumpectomies were irradical. CONCLUSION: This study has shown that (125)I seed localization is a novel and highly successful technique in localizing the tumour bed in patients who receive neo-adjuvant chemotherapy for breast cancer leading to a high percentage of radical margins in case of breast-conserving surgery.

Pharmacokinetics and metabolism of docetaxel administered as a 1-h intravenous infusion.

Docetaxel, a taxane antitumor agent, was administered to 24 patients by a 1-h intravenous infusion at a dose level of 100 mg/m(2) with pharmacokinetic monitoring. The plasma concentration-versus-time data were fitted with a three-compartment model. The mean area under the curve (AUC) for docetaxel was 3.1 +/- 0.9 h. mg/l and the clearance was 34.8 +/- 9.3 l/h per m(2). There was considerable interpatient pharmacokinetic variability. In 33% of the patient population, metabolites were detected in plasma samples collected 5-30 min after the end of the infusion. The cyclized oxazolidinedione metabolite M4 was most frequently present and was detected in 8 out of 24 patients with maximal concentrations between 0.022 and 0.23 mg/l. Logistic regression analysis was performed to predict M4 docetaxel metabolism. In the final model, alanine aminotransferase and alkaline phosphatase levels were the strongest predictors. No relationship was found between M4 metabolism and percentage decrease in neutrophil count in this study. Three patients with high M4 concentrations in plasma during course 1 suffered from most pronounced fluid retention (grade 2-3) after two to five courses.

A limited-sampling model for the pharmacokinetics of carboplatin administered in combination with paclitaxel.

PURPOSE: Carboplatin doses are often determined by using modified Calvert formulas. It has been observed that the area under the concentration versus time curve (AUC) for free carboplatin is lower than expected when modified formulas are used for carboplatin/paclitaxel chemotherapy combination regimens. By using limited-sampling models, the carboplatin AUC actually reached can easily be verified, and the dose adjusted accordingly. METHODS: In this report, we describe the development and validation of a limited-sampling model for carboplatin from 77 pharmacokinetic curves, when carboplatin is used in combination with paclitaxel. RESULTS: The following single-point model was selected as optimal: AUC carboplatin (min mg(-1) ml(-1)) = 418. c(2.5 h)(mg/ml) + 0.43 (min mg(-1) ml(-1)), where c(2.5 h) is the concentration (mg/ml) of carboplatin 2.5 h after the start of a 30-min infusion. This model proved to be unbiased (mean prediction error = 3.4 +/- 1.6%) and precise (root mean square error = 10.1 +/- 1.5%). CONCLUSIONS: The proposed model can be very useful for ongoing and future carboplatin/paclitaxel studies aimed to optimise and individualize treatment.

Topoisomerase I/II inhibitor intoplicine administered as a 24 h infusion: phase I and pharmacologic study.

Intoplicine, an antitumor drug which interacts with both topoisomerase enzymes I and II, has demonstrated a broad spectrum of activity in preclinical studies. This indicates further clinical evaluation. In the present phase I study, with the primary objective to determine the maximum tolerated dose, intoplicine was administered by a 24 h continuous infusion every 21 days to 32 patients with solid malignant tumors. The patients received 12-640 mg/m2 by a central venous catheter. Liver toxicity was dose limiting. One patient died in a hepatic coma after the first course (dose 640 mg/m2), which was associated with intoplicine treatment. Other side effects were sporadic and mild. Myelotoxicity was virtually absent. Twenty-two patients had stable disease for four to six courses of treatment. The plasma concentration-time curves were compatible with standard linear pharmacokinetic models, with a protracted terminal half-life (mean 115 h). Although one sudden death occurred probably due to intoplicine toxicity, we nevertheless feel that research with intoplicine should continue, mainly because of its preclinical activity and its unique mechanism of action. The recommended dose for phase II studies with intoplicine administered as a 24 h infusion is 384 mg/m2. Liver toxicity, also seen in studies employing other dosages and infusion durations, should be investigated extensively in further clinical studies.

A single 24-hour plasma sample does not predict the carboplatin AUC from carboplatin-paclitaxel combinations or from a high-dose carboplatin-thiotepa-cyclophosphamide regimen.

PURPOSE: It has been observed that the area under the free carboplatin concentration in plasma ultrafiltrate versus time curve (AUC) is related to toxicity and tumour response. For this reason, it can be important to measure the carboplatin AUC and subsequently adjust the dose to achieve a predefined target AUC. The use of limited sampling strategies enables relatively simple measurement and calculation of actual carboplatin AUCs. METHODS: We studied the performance of a limited sampling model, based on a single 24-h sample (the Ghazal-Aswad model). in 52 patients who received carboplatin in two different chemotherapy regimens (a carboplatin-paclitaxel combination and a high-dose carboplatin-thiotepa-cyclophosphamide combination). RESULTS: The measured mean AUC in our population was 4.1 min x mg/ml (median 3.9, range 1.9 6.3, SD 1.0 min x mg/ml). With the limited sampling model, the predicted mean AUC was 4.4 min x mg/ml (median 4.2, range 2.4-8.4, SD 1.2 min x mg/ml). Statistical analysis revealed that the model was slightly biased (MPE%, 6.5%), but imprecise (RMSE%, 20.6%) in our study population. CONCLUSION: Although easy and attractive to use, the Ghazal-Aswad formula is not precise enough to predict the carboplatin AUC, and needs to be evaluated prospectively in other patient populations.

Pharmacologic study of 3-hour 135 mg M-2 paclitaxel in platinum pretreated patients with advanced ovarian cancer.

Paclitaxel (Taxol(R)) is an active agent in platinum-refractory ovarian cancer. Since the available pharmacokinetic data of 135 mg m-2 paclitaxel administered by 3-h infusion are scarce and fragmented, we now describe a comprehensive pharmacologic study in a group of 13 patients who were pretreated with platinum for advanced ovarian cancer. The mean paclitaxel AUC was 10.3+/-2.4 h micromol l-1 (range 6.8-13.9 h micromol l-1). Quantification of the two major paclitaxel metabolites, 6alpha-hydroxypaclitaxel and 3'-p-hydroxypaclitaxel yielded AUCs of 0.44+/-0.30 h micromol l-1 and 0.31+/-0.20 h micromol l-1, respectively. The AUC of 3'-p-hydroxypaclitaxel was significantly different from that of patients with an altered hepatic function. The administration of 135 mg m-2 single-paclitaxel was safe, and the toxicities observed at higher doses in earlier studies were absent in this study. This is important, because the schedule and paclitaxel dose of 135 mg m-2 given by a 3-h infusion is expected to be used more frequently in combination with other cytotoxic agents with the aim of improving efficacy.

Carboplatin dosage formulae can generate inaccurate predictions of Carboplatin exposure in carboplatin/paclitaxel combination regimens.

Carboplatin is a frequently used antitumour agent recommended to be administered according to the Calvert formula: dose = AUC x (GFR+25), where GFR is the glomerular filtration rate as measured by (51)Cr-EDTA clearance and AUC is the targeted area under the carboplatin concentration versus time curve. In several modified Calvert formulae, the GFR is estimated on the basis of serum creatinine levels. We compared AUCs of carboplatin that were predicted by modified Calvert formulae with actual measured AUCs in 75 courses in patients with non-small cell lung cancer or ovarian cancer who were treated with the combination of carboplatin-paclitaxel. Predictions were made using two modified Calvert formulae, in which the GFR was calculated by serum creatinine level-based equations, according to Jelliffe (Eq. 1) and Cockroft-Gault (Eq. 2). We also studied the performance of a formula for the clearance of carboplatin, as proposed by Chatelut (Eq. 3). The actual measured mean AUC was 4.6 mg/ml.min (range 1.9 to 10.4 mg/ml.min, SD 1.7). Equation 1 overestimated the AUC by 32.9% with an imprecision of 43.0%, and equation 2 overestimated the AUC by 27.6% with an imprecision of 33.4%. For equation 3, an AUC overestimation of only 10.2%, but with an imprecision of 25.3%, was observed. In conclusion, all three equations overestimated the carboplatin AUCs and had poor precisions. We concluded that the real carboplatin AUCs were lower than calculated, using the three tested formulae. This may have important consequences for ongoing and future phase II and III studies with carboplatin-paclitaxel combinations, utilising these formulae to calculate the carboplatin dose. Thus far, the original Calvert dosage formula remains the 'golden standard'.

Tailor-made chemotherapy for cancer patients.

Dosages of anticancer agents are usually calculated from a uniform standard-the body surface area (BSA). Although the BSA is proportionate to many physiological functions, it is however only partially related to the overall drug clearance. Consequently, a wide variability in drug exposure and drug concentrations can be found between patients, by which some experience little toxicity, while others may show severe toxic symptoms. It seems clear that monitoring of plasma drug concentrations can be a useful tool to further optimize current cancer chemotherapy. The problem that pharmacokinetic parameters are usually generated from concentration-time profiles obtained after multiple venepunctures can be reduced by applying limited sampling models (LSM). Other tailor-made dosing strategies include the Calvert formula for carboplatin dosing and strategies based on the characteristics of the individual patient. It can be concluded that the determination of pharmacokinetic parameters and adjustment of the drug dose in each patient to a predefined 'target' value with an optimal therapeutic outcome, could contribute substantially to improvement of current chemotherapeutic treatment.

Phase I and pharmacologic study of the combination paclitaxel and carboplatin as first-line chemotherapy in stage III and IV ovarian cancer.

PURPOSE: To determine the maximum-tolerated dose for the combination paclitaxel and carboplatin administered every 4 weeks and to gain more insight into the pharmacokinetics and pharmacodynamics of this combination in previously untreated ovarian cancer patients. PATIENTS AND METHODS: Thirty-five chemotherapy-naive patients with suboptimally debulked stage III (tumor masses > 3 cm) and stage IV ovarian cancer were entered onto this phase I trial in which paclitaxel was administered as a 3-hour intravenous (IV) infusion at dosages of 125 to 225 mg/m2 immediately followed by carboplatin over 30 minutes at dosages of 300 to 600 mg/m2. A total of six courses was planned, followed by a second-look laparoscopy/laparotomy. Patients with a response and/or minimal residual disease at second-look laparoscopy received three additional courses. Twenty-six patients participated in the pharmacokinetic part of the study. RESULTS: The most important hematologic toxicity encountered was neutropenia. Neutropenia was more pronounced for the higher dose levels (DLs) and was cumulative. Thrombocytopenia was mild in the first eight DLs, but increased during the treatment courses. Nonhematologic toxicities consisted mainly of vomiting, neuropathy, fatigue, rash, pruritus, myalgia, and arthralgia. Dose-limiting toxicities (DLTs) in this trial were neutropenic fever, thrombocytopenia that required platelet transfusions, and cumulative neuropathy. Of 33 patients assessable for response, 26 major responders (78%, 20 complete response [CR] and six partial response [PR]) were documented. The maximal concentration (Cmax) of paclitaxel and the area under the concentration-time curve (AUC) were not different from the historical data for paclitaxel as a single agent. Retrospective analysis using a modified Calvert formula showed that the measured carboplatin AUCs in plasma ultrafiltrate (pUF) were 30% +/- 3.4% less than the calculated carboplatin AUC. Neutropenia was more pronounced than could be expected on the basis of the historical times above a threshold concentration greater than 0.1 mumol/L (T > or = 0.1 mumol/L) or 0.05 mumol/L (T > or = 0.05 mumol/L), and thrombocytopenia was less than could be expected from historical sigmoidal Emax models. CONCLUSION: The combination of paclitaxel 200 mg/ m2 and carboplatin 550 mg/m2 every 4 weeks is a well-tolerated treatment modality. The paclitaxel-carboplatin combination is highly active in stage III (bulky) and stage IV ovarian cancer. No indications for a pharmacokinetic drug-drug interaction between carboplatin and paclitaxel were found.

Phase II study of the combination carboplatin and paclitaxel in patients with ovarian cancer.

BACKGROUND: Recently the feasibility of combining carboplatin with paclitaxel has been demonstrated in dose-finding studies. Maximum tolerated doses were 550 mg/m2 and 200 mg/m2 (three hours), respectively. We report now a phase II study in ovarian cancer patients. PATIENTS AND METHODS: Twenty-one chemo-naïve patients with optimally (n = 6) or suboptimally (n = 15) debulked stage III or IV ovarian cancer were treated every three weeks for six courses with paclitaxel (200 mg/m2) as a three-hour infusion, immediately followed by carboplatin (550 mg/m2) as a 30-minute infusion. RESULTS: Uncomplicated neutropenia was the principal toxicity, with mild anemia occurring regularly. As observed in the preceding phase I study, a relative lack of thrombocytopenia, generally grade III was found. Other toxicities consisted of mild neurotoxicity, nausea and vomiting, alopecia, myalgia, and bone pain. All suboptimally debulked patients responded to therapy. Overall, 12 patients underwent second-look laparoscopy, which revealed a pathologically confirmed complete remission in six. The median follow-up interval at the time of analysis was 14 months. Twelve patients are currently free of progression, at 8+ to 19 +/- months after the start of therapy. CONCLUSION: The carboplatin/paclitaxel combination appears to be a well-tolerated regimen, yielding high response rates. This combination has now gone forward to be evaluated in prospective randomized trials versus the cisplatin/paclitaxel combination.

Clinical pharmacology of carboplatin administered in combination with paclitaxel.

The clinical pharmacology of carboplatin (C) administered with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) (P) was investigated in two phase I studies undertaken in 83 previously untreated patients with either non-small cell lung cancer or ovarian cancer. Carboplatin was administered over 30 minutes and paclitaxel over 3 hours. Both agents were given every 4 weeks. Non-small cell lung cancer patients were randomized to two administration sequences, either carboplatin followed by paclitaxel (C-->P) or the reverse (P-->C). Each patient received the alternate sequence during the second and subsequent courses. Ovarian cancer patients uniformly received paclitaxel before carboplatin. Platinum concentrations in plasma ultrafiltrate were measured via flameless atomic absorption spectrometry, and 122 concentration-time curves were obtained. For non-small cell lung cancer patients, the mean area under the concentration-time curve (AUC) per 300 mg/m2 carboplatin was 3.52 mg/mL x min (range, 1.94 to 5.83) for the sequence C-->P and 3.62 mg/mL x min (range, 1.91 to 5.01) for the sequence P-->C. No sequence-dependent effect was observed (P > .5). For ovarian cancer patients, the mean AUC per 300 mg/m2 carboplatin was 3.83 mg/mL x min (range, 2.72 to 6.10), showing no difference when compared with data derived from non-small cell lung cancer patients (P = .13). In addition, the carboplatin AUC was not influenced by increasing paclitaxel doses from 100 to 250 mg/m2. Neutropenia was the principal toxicity, and anemia was frequent. However, there was a striking lack of thrombocytopenia. Modeling of the relationship between the carboplatin AUC and the decrease in platelets revealed a 50% decrease in platelets at a carboplatin AUC (AUC50) of 6.3 mg/mL x min. This contrasts with historical data documenting a carboplatin AUC50 of 4.0 mg/mL x min. Our findings suggest that there is a considerable interaction of both drugs at the cellular level, with at least an additive effect of carboplatin on the main hematologic toxicity of paclitaxel (ie, neutropenia). There is also a protective effect exerted by paclitaxel on carboplatin-related toxicity (ie, thrombocytopenia). The clear protective effect of paclitaxel in this combination suggests that it is possible to reduce the dose interval to 3 weeks. Studies are in progress to test this hypothesis and to investigate the underlying pharmacologic interactions.

An overview of the clinical pharmacology of topotecan.

Topotecan (Hycamtin; SmithKline Beecham Pharmaceuticals, Philadelphia, PA), a topoisomerase I inhibitor, is a semisynthetic camptothecin that has been structurally modified for increased water solubility. The closed lactone ring predominates at acidic pH, but the reverse reaction of the parent into the metabolite predominates at physiologic pH. The pharmacokinetic profile of topotecan is usually characterized by a two-compartment model and is linear in the dose range of 0.5 to 3.5 mg/m2. Following intravenous administration for 5 days at doses of 0.5 to 1.5 mg/m2/d as a 30-minute infusion, topotecan has a volume of distribution of approximately 130 L. Mean plasma clearance for topotecan (total) was approximately 1,000 mL/min with a plasma half-life of 2 to 3 hours. Renal clearance is an important determinant of topotecan elimination, with approximately 30% of the dose excreted in the urine. In three phase I studies in which the schedule of five daily doses every 21 or 28 days was investigated, all found 1.5 mg/m2/d to be the maximum tolerated dose. Neutropenia (reversible and noncumulative over time) was the major dose-limiting toxicity; fevers and infections were infrequently reported. The magnitude of topotecan exposure was correlated to the observed myelosuppression.