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C J van Groeningen

Publications and source records attributed to C J van Groeningen.

At least 19 recordsLinked to original sources
PubMed2006

The determination of gemcitabine and 2'-deoxycytidine in human plasma and tissue by APCI tandem mass spectrometry.

A fast, sensitive and accurate method for the determination of gemcitabine (difluorodeoxycytidine; dFdC) and deoxycytidine (CdR) in human plasma/tissue was developed using LC-MS/MS techniques. Effectiveness of the method is illustrated with the analysis of plasma from a phase I trial of dFdC administered as a 24h infusion. The method was developed using (15)N(3) CdR as an internal standard across the concentration range of 1-500ng/ml, using a cold alcohol-protein precipitation followed by desorption with freeze drying. Sample clean-up for LC-MS/MS analysis was performed by an innovative liquid/liquid back extraction with ethyl acetate and water. Chromatography was performed using a Chrompak-spherisorb-phenyl-column (3.1mmx200mm, 5microm) with a 50mM formic acid: acetonitrile (9:1) mobile phase eluted at 1ml/min. Extracted samples were observed to be stable for a minimum of 48h after extraction when kept at 4 degrees C. Detection was performed using an atmospheric pressure chemical ionization (APCI) source and mass spectrometric positive multi-reaction-monitoring-mode (+MRM) for dFdC (264 m/z; 112 m/z), CdR (228 m/z; 112 m/z), and (15)N(3) CdR (231 m/z; 115 m/z) at an ion voltage of +3500V. The accuracy, precision and limit-of-quantitation (LOQ) were as follows: dFdC: 99.8%, +/-7.9%, 19nM; CdR: 100.0%, +/-5.3%, 22nM, linear range LOQ to 2microM. During 24h infusion dFdC levels were detected with no interference from either CdR or difluorodeoxyuridine (dFdU). CdR co-eluted with dFdC but selectivity demonstrated no "crosstalk" between the compounds. In conclusion the analytical assay was very sensitive, reliable and robust for the determination of plasma and tissue concentrations of dFdC and CdR.

Chromatography, High Pressure Liquid↗
PubMed2006

Iron absorption during epoetin alfa therapy for chemotherapy-associated anaemia.

Absorption of a physiological dose of ferrous iron was studied in 18 patients with solid malignancy receiving epoetin therapy for mild chemotherapy-associated anemia. The historical control group consisted of 25 iron replete volunteers (iron absorption 20 +/- 11% in males and 26 +/- 13% in females) and 21 patients with uncomplicated iron deficiency (iron absorption 71 +/- 19%). Iron absorption was increased in the majority of the cancer patients (iron absorption 59 +/- 35%). There were no significant differences in iron absorption between cancer patients who were iron replete or iron deficient according to current clinical practice guidelines (iron deficiency: transferrin saturation < 20% and/or serum ferritin < 100 ng/mL). Red cell iron incorporation was not disturbed in the majority (89%) of patients.

Adult↗
PubMed2006

Analysis of deoxycytidine accumulation in gemcitabine treated patients.

Deoxycytidine (CdR) analogs are increasingly popular as chemotherapeutic agents and their effectiveness can be linked to the direct competition with active forms of endogenous CdR. A tandem mass spectrometric assay was developed to determine the plasma concentrations of CdR. Plasma extracts were prepared by protein precipitation and an ethyl acetate/water back extraction, and then separated chromatographically. Detection parameters were optimized for multi-reaction monitoring (MRM) tandem mass spectrometry and assay efficiency was improved using 15N3 CdR as an isotopic internal standard. Preliminary results from a gemcitabine trial are shown which indicate that CdR concentrations increase systemically during infusion, from about 5 nM to 78 nM after hepatic artery infusion and to 102 nM after systemic infusion for 24 hours. The developed assay demonstrated good sensitivity and selectivity for CdR.

Antimetabolites, Antineoplastic↗
PubMed2005

Seven year update of an EORTC phase III trial of high-dose intensity M-VAC chemotherapy and G-CSF versus classic M-VAC in advanced urothelial tract tumours.

EORTC protocol 30924 is an international randomized trial reporting a 7.3 year update of a 2 weekly regimen of high-dose intensity chemotherapy with M-VAC plus granulocyte colony stimulating factor (HD-M-VAC) compared to classic M-VAC in advanced transitional cell carcinoma (TCC). Two hundred and sixty three untreated patients with bidimensionally measurable TCC were included. In an intention to treat analysis, there were 28 complete responses (CR) (21%) and 55 partial responses (PR) (41%), for an overall response rate (RR) of 64% on the HD-M-VAC arm. On M-VAC, there were 12 CR (9%) and 53 PR (41%), for an overall RR of 50% . The P-value for the difference in CR was 0.009; and for RR, was 0.06. After a median follow-up of 7.3 years, 24.6% are alive on the HD-M-VAC arm vs. 13.2% on the M-VAC arm. Median progression-free survival was better with HD-MVAC (9.5 months) vs. M-VAC (8.1 months). The mortality hazard ratio (HR) was 0.76. The 2-year survival rate for HD-M-VAC was 36.7% vs. 26.2% for M-VAC. At 5 years, the survival rate was 21.8% in the HD-M-VAC vs. 13.5%. Median survival was 15.1 months on HD-MVAC and 14.9 months on M-VAC. There was one death from toxicity in each arm; and more patients died to malignant disease in the M-VAC arm (76%) than in the HD-M-VAC arm (64.9%). With longer follow-up initial results have been confirmed, and shows that HD-M-VAC produces a borderline statistically significant relative reduction in the risk of progression and death compared to M-VAC.

Adult↗
PubMed2005

No evidence of gemcitabine accumulation during weekly administration.

Some anticancer agents tend to accumulate during repeated administration. We determined whether gemcitabine or its metabolites would accumulate during repeated administration. Gemcitabine was administered over two courses with each course consisting of a 30-min infusion at 1000 mg/m(2) weekly for 3 weeks followed by 1 week of rest. In 14 patients we evaluated eventual accumulation by comparing the concentrations in blood samples taken before, and at 30 and 60 min after the start of infusion on days 1, 8 and 15, in both cycles. At the end of the infusion gemcitabine concentrations at day 1 of both courses varied between 18 and 77 microM and at day 15 between 13 and 90 microM. The mean ratios day 8/day 1 and day 15/day 1 varied from 0.94 to 1.18. For the inactive metabolite 2',2'-difluoro-2'-deoxyuridine (dFdU) these values varied between 54 and 152 microM and 55 and 157, respectively, and the ratios from 0.96 to 1.08. The concentration of the active metabolite of gemcitabine, gemcitabine triphosphate (dFdCTP) in peripheral white blood cells, ranged between 37 and 283 pmol/10(6) cells at the end of infusion on day 1 and 35 and 115 pmol/10(6) cells on day 15. Potential accumulation was evaluated using a mixed effects model and no evidence was observed of accumulation for either gemcitabine or its metabolites. Gemcitabine can be administered safely without the risk that the drug will accumulate.

Aged↗
PubMed2005

Phase II study of tailored chemotherapy for advanced colorectal cancer with either 5-fluouracil and leucovorin or oxaliplatin and irinotecan based on the expression of thymidylate synthase and dihydropyrimidine dehydrogenase.

BACKGROUND: Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) are essential enzymes for 5-fluorouracil (5-FU) metabolism. In patients with advanced colorectal cancer (ACRC), retrospective studies have shown that low expression levels of TS and DPD correlated with response to 5-FU. We performed a prospective study in which the choice of first-line chemotherapy with either 5-FU or a non-5-FU containing regimen was based on TS and DPD expression. PATIENTS AND METHODS: Fresh-frozen samples of metastases were obtained from 58 previously untreated patients with ACRC. mRNA expression of TS and DPD was quantified using an RT-PCR assay. Patients with low tumor expression of both TS and DPD received weekly bolus 5-FU/leucovorin (LV) 500 mg/m2 (group A); patients with high TS and/or DPD received 3-weekly oxaliplatin 85 mg/m2 and irinotecan 200 mg/m2 (group B). After progression, cross-over to the alternative regimen was attempted. RESULTS: Of 53 eligible patients, 31 had tumors with both low TS and low DPD, and were treated in group A. A response was observed in 11 patients [35%; 95% confidence interval (CI) 19% to 54%]. Cross-over to second-line oxaliplatin/irinotecan resulted in a partial response in two out of 16 patients (13%; 95% CI 1% to 38%). In group B, four out of 22 patients responded (18%; 95% CI 5% to 40%), while no responses were observed in 12 patients after cross-over to 5-FU/LV (0%; 95% CI 0% to 28%). CONCLUSIONS: Prospective selection of 5-FU/LV chemotherapy based on low TS and DPD expression in patients with ACRC did not confirm the high response rates reported in retrospective studies. The procedure of obtaining metastatic tissue and quantitation of enzymes appeared feasible but cumbersome. Before assessing the clinical utility of a predictive marker in a randomized trial, future studies should focus on prospective validation of the assay in a large and well defined population.

Adult↗
PubMed2005

Phase I and pharmacokinetic study of the novel chemoprotector BNP7787 in combination with cisplatin and attempt to eliminate the hydration schedule.

BNP7787 (disodium 2,2'-dithio-bis-ethane sulphonate; Tavocept) is a novel agent developed to protect against cisplatin (cis-diammine-dichloroplatinum(II))-associated chronic toxicities. In this study, we determined the recommended dose of BNP7787 when preceding a fixed dose of cisplatin, the pharmacokinetics (PKs) and the possible reduction of saline hydration. Patients with advanced solid tumours received BNP7787 in escalating doses of 4.1-41 g m(-2) as a 15-min intravenous (i.v.) infusion followed by cisplatin 75 mg m(-2) as a 60-min i.v. infusion together with pre- and postcisplatin saline hydration in a volume of 2200 ml; cycles were repeated every 3 weeks. PK was carried out using BNP7787, cisplatin and the combination. Twenty-five patients were enrolled in stage I of the study to determine the recommended dose of BNP7787. No dose-limiting toxicity was reached. The highest dose level of 41 g m(-2) resulted in a low incidence of grade 2 toxicities, being nausea and vomiting, dry mouth or bad taste and i.v. injection site discomfort. Doses of BNP7787 > or = 18.4 g m(-2) did not show a drug interaction between BNP7787 and cisplatin. In stage II of the study, patients received a fixed dose of BNP7787 of 18.4 g m(-2) preceding cisplatin and were entered in prespecified reduced saline hydration steps. A total of 21 patients in cohorts of six to nine patients received reduced saline hydration of 1600 ml (step A), 1000 ml (step B) and 500 ml (step C). In step C, two out of six evaluable patients experienced grade 1 nephrotoxicity. Cisplatin acute toxicities in all 46 patients were as expected. Only five patients complained of paresthesias grade 1 and six developed slight audiometric changes. Partial tumour response was observed in four patients and stable disease in 15 patients. In conclusion, BNP7787 was tolerated well up to doses of 41 g m(-2). The recommended dose of 18.4 g m(-2) enabled safe reduction of the saline hydration schedule for cisplatin to 1000 ml. Further studies will assess whether BNP7787 offers protection against platinum-related late side effects.

Adult↗
PubMed2005

Effects of early intervention with epoetin alfa on transfusion requirement, hemoglobin level and survival during platinum-based chemotherapy: Results of a multicenter randomised controlled trial.

This work was conducted to evaluate the effect of early intervention with epoetin alfa (EPO) on transfusion requirements, hemoglobin level (Hb), quality of life (QOL) and to explore a possible relationship between the use of EPO and survival, in patients with solid tumors receiving platinum-based chemotherapy. Three hundred and sixteen patients with Hb12.1g/dL were randomised 2:1 to EPO 10000 IU thrice weekly subcutaneously (n = 211) or best supportive care (BSC) (n = 105). The primary end point was proportion of patients transfused while secondary end points were changes in Hb and QOL. The protocol was amended before the first patient was recruited to also prospectively collect survival data. EPO therapy significantly decreased transfusion requirements (P < 0.001) and increased Hb (P < 0.005). EPO-treated patients had significantly improved QOL compared with BSC patients (P < 0.05). Kaplan-Meier estimates showed no differences in 12-month survival (P = 0.39), despite a significantly greater number of patients with metastatic disease in the EPO group (78% vs. 61%, P = 0.001). EPO was well tolerated. This study has shown that early intervention with EPO can result in a significant reduction of transfusion requirements and increases in Hb and QOL in patients with mild anemia during platinum-based chemotherapy.

Adult↗
PubMed2004

Carcinomatous meningitis in cancer of the uterine cervix.

Carcinomatous meningitis is extremely rare in cervical cancer. The diagnosis of carcinomatous meningitis is a difficult one when clinical symptoms are limited and radiographic imaging is normal. Demonstration of malignant cells in the cerebrospinal fluid remains the gold standard to establish the diagnosis. For patients without bulky disease who can be treated with radiotherapy, standard treatment for carcinomatous meningitis is chemotherapy, which may be administered intrathecally. Despite the poor prognosis, treatment may result in effective palliation. We describe a 54-year-old patient who was diagnosed with carcinomatous meningitis in the course of metastatic cervical cancer and who responded to administration of intrathecal methotrexate.

Antimetabolites, Antineoplastic↗
PubMed2004

Polymorphism of the thymidylate synthase gene and thymidylate synthase levels in colon cancer cell lines and different tissues of colorectal cancer patients.

In a panel of 18 colon cancer cell lines we found that the thymidylate synthase (TS) genotype was related to TS enzyme activity, but not to TS protein and mRNA levels. In addition, no relation with drug sensitivity was observed. TS genotyping of different tissues from 78 colorectal cancer patients revealed a high level of homology in polymorphic status between normal and malignant tissues and the heterozygous genotype to be the most frequent.

Antimetabolites, Antineoplastic↗
PubMed2004

Continuous infusion of hepatic arterial irinotecan in pretreated patients with colorectal cancer metastatic to the liver.

BACKGROUND: Irinotecan is an active drug in colorectal cancer. In patients with liver metastases, hepatic arterial infusion of irinotecan could theoretically result in higher exposure to the drug. In order to determine the efficacy of hepatic arterial irinotecan we conducted a phase II study in pretreated patients with liver metastases of colorectal cancer. PATIENTS AND METHODS: Patients with measurable liver metastases of colorectal cancer with World Health Organization performance status (WHO PS) <2 were treated with a 5-day continuous infusion of hepatic arterial irinotecan every 3 weeks at a dose of 20 mg/m(2)/day. RESULTS: Of the 25 patients included, 22 were evaluable for response. Three of 22 patients (13.6%) had a partial response, nine (40.9%) had stable disease and 10 (45.4%) had progressive disease. No complete responses were observed. Median time to progression was 2.8 (range 1.2-23.8) months. Major toxicities were vomiting and diarrhea. There was no major hematological toxicity. CONCLUSIONS: Five-day continuous hepatic arterial infusion of irinotecan 20 mg/m(2)/day has low activity in patients with liver metastases of colorectal cancer previously treated by chemotherapy.

Adult↗
PubMed2004

Phase II trial of cisplatin and gemcitabine in patients with advanced gastric cancer.

BACKGROUND: This phase II study was performed to determine the efficacy and toxicity of cisplatin and gemcitabine in patients with advanced gastric cancer. PATIENTS AND METHODS: Forty chemo-naïve patients with measurable locoregionally advanced or metastatic gastric cancer were included; the median patient age was 53 years (range 35-71). Cisplatin was administered at a dose of 50 mg/m2, given in 1 h intravenously (i.v.) on days 1 and 8, followed after 24 h by gemcitabine at a dose of 800 mg/m2 given in 30 min i.v. on days 2, 9 and 16, every 28 days. RESULTS: A median number of four therapy cycles were given (range 2-8). Myelosuppresion was the most important toxicity. Grade 3-4 thrombopenia was observed in 19 patients (48%) and grade 3-4 leukopenia was observed in 23 (58%). Myelotoxicity was cumulative and caused omission of gemcitabine on day 16 in 55% of cycles. Non-haematological toxicity consisted mainly of grade 1-2 nausea and vomiting. Objective responses were observed in 30% of patients including two complete remissions and 10 partial remissions. Median survival was 11 months (range 3-27+). CONCLUSIONS: This cisplatin-gemcitabine regimen had moderate efficacy in patients with advanced gastric cancer, with manageable toxicity. Further studies with this combination may be warranted.

Adenocarcinoma↗
PubMed2003

Compassionate use programme of irinotecan in colorectal cancer patients in The Netherlands.

BACKGROUND: Irinotecan is an effective treatment for metastatic colorectal cancer. However, its use may be associated with troublesome adverse effects such as delayed diarrhoea, acute cholinergic syndrome and neutropenic infection. The manufacturer decided to release irinotecan for compassionate use in The Netherlands prior to its regulatory approval (June 1998) and first introduction for second-line treatment of metastatic colorectal cancer. In view of the drug's adverse effect profile this was done in a carefully controlled manner. METHODS: Irinotecan was made available to patients with colorectal cancer with elaborate precautions. Treating physicians requesting irinotecan for compassionate use received a protocol, providing recommendations for the proper use and the prevention/management of potentially troublesome adverse events. Limited demographic, toxicity and efficacy data were collected. RESULTS: Between June 1997 and September 1998, 112 patients were registered for this programme, 103 of whom actually received irinotecan. The percentage of patients experiencing grade 3-4 adverse effects was relatively low: delayed diarrhoea in 17%, nausea and vomiting 17%, acute cholinergic syndrome 6%, febrile neutropenia 4% and neutropenic infection 2%. Five partial tumour responses and a high proportion of patients with 'no change' were noted. CONCLUSIONS: The carefully controlled release of irinotecan for compassionate use with a very detailed protocol for guidance and advice on safety precautions seems to have contributed to the relatively safe use of the drug outside the setting of a formal clinical trial.

Adult↗
PubMed2002

Induction of thymidylate synthase as a 5-fluorouracil resistance mechanism.

Thymidylate synthase (TS) is a key enzyme in the de novo synthesis of 2'-deoxythymidine-5'-monophosphate (dTMP) from 2'-deoxyuridine-5'-monophosphate (dUMP), for which 5,10-methylene-tetrahydrofolate (CH(2)-THF) is the methyl donor. TS is an important target for chemotherapy; it is inhibited by folate and nucleotide analogs, such as by 5-fluoro-dUMP (FdUMP), the active metabolite of 5-fluorouracil (5FU). FdUMP forms a relatively stable ternary complex with TS and CH(2)THF, which is further stabilized by leucovorin (LV). 5FU treatment can induce TS expression, which might bypass dTMP depletion. An improved efficacy of 5FU might be achieved by increasing and prolonging TS inhibition, a prevention of dissociation of the ternary complex, and prevention of TS induction. In a panel of 17 colon cancer cells, including several variants with acquired resistance to 5FU, sensitivity was related to TS levels, but exclusion of the resistant variants abolished this relation. For antifolates, polyglutamylation was more important than the intrinsic TS level. Cells with low p53 levels were more sensitive to 5FU and the antifolate raltitrexed (RTX) than cells with high, mutated p53. Free TS protein down-regulates its own translation, but its transcription is regulated by E2F, a cell cycle checkpoint regulator. Together, this results in low TS levels in stationary phase cells. Although cells with a low TS might theoretically be more sensitive to 5FU, the low proliferation rate prevents induction of DNA damage and 5FU toxicity. TS levels were not related to polymorphisms of the TS promoter. Treatment with 5FU or RTX rapidly induced TS levels two- to five-fold. In animal models, 5FU treatment resulted in TS inhibition followed by a two- to three-fold TS induction. Both LV and a high dose of 5FU not only enhanced TS inhibition, but also prevented TS induction and increased the antitumor effect. In patients, TS levels as determined by enzyme activity assays, immunohistochemistry and mRNA expression, were related to a response to 5FU. 5FU treatment initially decreased TS levels, but this was followed by an induction, as seen with an increased ratio of TS protein over TS-mRNA. The clear retrospective relation between TS levels and response now forms the basis for a prospective study, in which TS levels are measured before treatment in order to determine the treatment protocol.

Animals↗
PubMed2002

Gemcitabine-radiotherapy in patients with locally advanced pancreatic cancer.

A feasibility study was performed to assess the toxicity and efficacy of a combination of gemcitabine-radiotherapy in patients with locally advanced pancreatic cancer (LAPC). 24 patients (15 females and 9 males) with measurable LAPC were included; the median age of the patients was 63 years (range 39-74 years). The performance status ranged from 0 to 2. Gemcitabine was administered at a dose of 300 mg/m(2), concurrent with radiotherapy, three fractions of 8 Gy, on days 1, 8 and 15. When compliance allowed, gemcitabine alone was continued thereafter, at 1000 mg/m(2), weekly times 3, every 4 weeks, depending on the response and toxicity. All patients were evaluable for toxicity and response. The objective response rate was 29.2% (1 complete remission+6 partial remissions); 12 patients had stable disease. However, 2 of the radiological partial remissions were shown to be complete remissions by pathology assessment. Median duration of response was 3 months (range 1-35+months). Median time to progression was 7 months (range 2-37+months). Median survival was 10 months (range 3-37+months). Dose reduction or omission of gemcitabine was necessary in 10 patients. Non-haematological toxicity consisted of 87.5% nausea and vomiting grade I-II, diarrhoea 54%, ulceration in stomach and duodenum 37.5% (20.8% ulceration with bleeding); 1 patient developed a fistula between the duodenum and aorta, 5 months after treatment. Anaemia grade III-IV was observed in 8.3% of the patients. Neutropenia grade III-IV was observed in 8.3%, thrombocytopenia grades III-IV in 16.7%. In 1 patient who underwent resection postchemoradiation, no viable tumour cells were found. In addition, in the patient who suddenly died of a fistula between the duodenum and aorta, no viable tumour cells were detectable at autopsy. Although the toxicity of this treatment was occasionally severe, the response and survival are encouraging and warrant further studies of this combination.

Adult↗
PubMed2001

Randomized phase III trial of high-dose-intensity methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) chemotherapy and recombinant human granulocyte colony-stimulating factor versus classic MVAC in advanced urothelial tract tumors: European Organization for Research and Treatment of Cancer Protocol no. 30924.

PURPOSE: This randomized trial evaluated antitumor activity of and survival asociated with high-dose-intensity chemotherapy with methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) plus granulocyte colony-stimulating factor (HD-MVAC) versus MVAC in patients with advanced transitional-cell carcinoma (TCC). PATIENTS AND METHODS: A total of 263 patients with metastatic or advanced TCC who had no prior chemotherapy were randomized to HD-MVAC (2-week cycles) or MVAC (4-week cycles). RESULTS: Using an intent-to-treat analysis, at a median follow-up of 38 months, on the HD-MVAC arm there were 28 complete responses (CRs) (21%) and 55 partial responses (PRs) (41%), for an overall response of 62% (95% confidence interval [CI], 54% to 70%). On the MVAC arm, there were 12 CRs (9%) and 53 PRs (41%), for an overall response of 50% (95% CI, 42% to 59%). The P value for the difference in CR rate was.009; and for the overall response, it was.06. There was no statistically significant difference in survival (P =.122) or time to progression (P =.114). Progression-free survival was significantly better with HD-MVAC (P=.037; hazard ratio.75; 95% CI.58 to.98). The median progression-free survival time was 9.1 months on the HD-MVAC arm versus 8.2 months on the MVAC arm. The 2-year progression-free survival rate was 24.7% for HD-MVAC (95% CI, 17.1% to 32.3%) versus 11.6% for MVAC (95% CI, 5.9% to 17.4%). CONCLUSION: With HD-MVAC, it was possible to deliver twice the doses of cisplatin and doxorubicin in half the time, with fewer dose delays and less toxicity. Although a 50% difference in median overall survival was not detected, a benefit was observed in progression-free survival, CR rates, and overall response rates with HD-MVAC.

Adult↗