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Marcel Bontenbal

    Marcel Bontenbal

    Dual-parameter flow cytometry, following bromodeoxyuridine (BrdUrd) incorporation and propidium iodide (PI) uptake into DNA, was used to study the effects of oestradiol and/or insulin on cell cycle kinetics of human breast cancer cells in... more
    Dual-parameter flow cytometry, following bromodeoxyuridine (BrdUrd) incorporation and propidium iodide (PI) uptake into DNA, was used to study the effects of oestradiol and/or insulin on cell cycle kinetics of human breast cancer cells in vitro. After a lag-period of 6-12 h, an optimum in the percentage of S-phase cells was reached between 18 and 24 h after hormone administration. A 1 h pulse of oestradiol was as effective as the continuous presence of oestradiol in pushing the cells from quiescent growing cultures into the cell cycle. A 1 h pulse of insulin was less effective than continuous administration. The addition of doxorubicin resulted in an accumulation of the cells in the late S/G2M-phases. It is concluded that dual-parameter flow cytometry allows accurate assessment of the effects of hormones and chemotherapy on the cell cycle. Therefore this method is very suitable for studying the interaction of hormones and chemotherapy on cell growth.
    Benefit from chemotherapy treatment in breast cancer patients is determined by the molecular make-up of the tumour. In a retrospective analysis, we determined the molecular subtypes of breast cancer originally defined by expression... more
    Benefit from chemotherapy treatment in breast cancer patients is determined by the molecular make-up of the tumour. In a retrospective analysis, we determined the molecular subtypes of breast cancer originally defined by expression microarrays by immunohistochemistry in tumours of patients who took part in a randomised study of adjuvant high-dose chemotherapy in breast cancer. In addition, the topoisomerase II alpha (TOP2A) amplification status was determined by fluorescence in situ hybridisation and chromogenic in situ hybridisation. 411 of the 753 tumours (55%) were classified as luminal-like, 137 (18%) as basal-like and 205 (27%) as human epithelial receptor type 2 (HER2) amplified. The basal-like tumours were defined as having no expression of ER and HER2; 98 of them did express epidermal growth factor receptor and/or cytokeratin 5/6. The luminal-like tumours had a significantly better recurrence free and overall survival than the other two groups. From the 194 HER2-positive tum...
    To obtain practical experience with venlafaxine for hot flushes in breast cancer patients and incorporate this in a treatment protocol. Twenty-two women with a history of breast cancer (mean age 49.2 years, range 35-65) were referred for... more
    To obtain practical experience with venlafaxine for hot flushes in breast cancer patients and incorporate this in a treatment protocol. Twenty-two women with a history of breast cancer (mean age 49.2 years, range 35-65) were referred for consideration of treatment with venlafaxine for hot flushes. Patients received extensive information on treatment with venlafaxine and were advised to self-monitor the frequency of their hot flushes. Eight women did not start venlafaxine because they had no postmenopausal complaints, were lost to follow-up, had too low a frequency of hot flushes, or refused treatment. Eventually 14 women started venlafaxine. Two of them did not tolerate venlafaxine, four reported some effect but stopped because of side effects, two women had no effect whatsoever. Six women observed a clear ( > 50%) reduction in their hot flush frequency that was maintained at a median follow-up of 13 months. The group of patients referred for treatment was more heterogeneous and ...
    Metastatic breast cancer is still an incurable disease. Standard hormonal and chemotherapeutic treatment modalities yield at the best a survival advantage of 1 to 2 years. However, palliation is still the second, very important goal of... more
    Metastatic breast cancer is still an incurable disease. Standard hormonal and chemotherapeutic treatment modalities yield at the best a survival advantage of 1 to 2 years. However, palliation is still the second, very important goal of treatment for metastatic disease. First-line chemotherapeutic treatment with an anthracycline-containing regimen induces a response in about half the patients. In second-line treatment docetaxel is an effective agent even in patients failing first-line therapy with an anthracycline-containing regimen. There is no effective standard third-line chemotherapy scheme.
    The EORTC Breast Cancer Cooperative Group carried out a randomized trial to compare doxorubicin with epirubicin as second-line chemotherapy in patients with metastatic breast cancer. Two hundred and fifty-nine patients with at least one... more
    The EORTC Breast Cancer Cooperative Group carried out a randomized trial to compare doxorubicin with epirubicin as second-line chemotherapy in patients with metastatic breast cancer. Two hundred and fifty-nine patients with at least one site of metastatic disease entered this trial, of whom 232 patients were eligible. Treatment consisted of doxorubicin 75 mg m(-2) or epirubicin 90 mg m(-2) i.v. every 3 weeks. The overall response rates for doxorubicin and epirubicin were 36% and 28% respectively (P = 0.173). The median time to progression was 23 weeks for doxorubicin and 19 weeks for epirubicin (P = 0.063) and the median duration of response was 40 weeks for doxorubicin and 32 weeks for epirubicin (P = 0.059). The median survival was 47 weeks for doxorubicin and 44 weeks for epirubicin (P = 0.196). Leucocyte count on retreatment day (P = 0.011) and platelet nadir (P = 0.031) were significantly lower in the doxorubicin-treated group. Also mucositis (P < 0.001), diarrhoea (P = 0.00...
    Suppression of the secretion of prolactin, growth hormone and insulin-like growth factor 1 (IGF-1) might be important in the growth regulation and treatment of breast cancer. Because oestrogens may counteract the anti-tumour effects of... more
    Suppression of the secretion of prolactin, growth hormone and insulin-like growth factor 1 (IGF-1) might be important in the growth regulation and treatment of breast cancer. Because oestrogens may counteract the anti-tumour effects of such treatment, the combination of an anti-oestrogen (tamoxifen), a somatostatin analogue (octreotide) and a potent anti-prolactin (CV 205-502) might be attractive. In this respect, we performed a first exploratory long-term study on the feasibility of combined treatment and possible clear differences in endocrine and anti-tumour effects during such combined treatment vs standard treatment with tamoxifen alone. Twenty-two post-menopausal patients with metastatic breast cancer (ER and/or PR positive or unknown) were randomized to receive either 40 mg of tamoxifen per day or the combination of 40 mg of tamoxifen plus 75 microg of CV 205-502 orally plus 3 x 0.2 mg of octreotide s.c. as first-line endocrine therapy. An objective response was found in 36% ...
    PS2, an oestrogen-inducible protein, was measured in the cytosol of 230 primary tumours from patients who were subjected to first-line tamoxifen therapy for advanced disease without prior adjuvant therapy with tamoxifen. PS2 correlated... more
    PS2, an oestrogen-inducible protein, was measured in the cytosol of 230 primary tumours from patients who were subjected to first-line tamoxifen therapy for advanced disease without prior adjuvant therapy with tamoxifen. PS2 correlated positively with oestrogen receptor (ER, P < 0.01) and progesterone receptor content (PgR, P < 0.001), and with the length of progression-free survival (PFS, P = 0.05). Although not statistically significant, higher levels of PS2 (> or = 10 ng mg-1 protein) were also associated with increased probability of response to tamoxifen treatment and a longer total post-relapse survival (PRS). ER, PgR, menopausal status, site of disease and prior adjuvant chemotherapy were all associated with response to tamoxifen therapy and with PFS. In multivariate analysis for PFS, low levels of ER and PgR, visceral metastasis, a disease-free interval of less than 1 year and prior adjuvant chemotherapy were all significantly associated with an increased probabilit...
    Purpose To compare the efficacy and safety of doxorubicin and docetaxel (AT) with fluorouracil, doxorubicin, and cyclophosphamide (FAC) as first-line chemotherapy for metastatic breast cancer (MBC). Patients and Methods Patients (n = 216)... more
    Purpose To compare the efficacy and safety of doxorubicin and docetaxel (AT) with fluorouracil, doxorubicin, and cyclophosphamide (FAC) as first-line chemotherapy for metastatic breast cancer (MBC). Patients and Methods Patients (n = 216) were randomly assigned to either AT (doxorubicin 50 mg/m2 and docetaxel 75 mg/m2) or FAC (fluorouracil 500 mg/m2, doxorubicin 50 mg/m2, and cyclophosphamide 500 mg/m2); both regimens were administered on day 1, every 3 weeks. Results A median number of six cycles was delivered in both arms, with a median relative dose-intensity of more than 98%. Median time to progression (TTP) and median overall survival (OS) were significantly longer for patients on AT compared with FAC (TTP: 8.0 v 6.6 months, respectively; P = .004; and OS: 22.6 v 16.2 months, respectively; P = .019). The overall response rate (ORR) was significantly higher in patients on AT compared with FAC (58% v 37%, respectively; P = .003). The ORR on AT was also higher in patients with vis...
    Purpose To evaluate and compare health-related quality of life (HRQOL) after conventional- and high-dose adjuvant chemotherapy in patients with high-risk breast cancer. Patients and Methods Patients were randomly assigned to either a... more
    Purpose To evaluate and compare health-related quality of life (HRQOL) after conventional- and high-dose adjuvant chemotherapy in patients with high-risk breast cancer. Patients and Methods Patients were randomly assigned to either a conventional or high-dose chemotherapy regimen; both regimens were followed by radiotherapy and tamoxifen. HRQOL was evaluated until disease progression using the Short Form-36 (SF-36), Visual Analog Scale, and Rotterdam Symptom Checklist and assessed every 6 months for 5 years after random assignment. For the SF-36, data from healthy Dutch women with the same age distribution served as reference values. Results Eight hundred four patients (conventional-dose chemotherapy, n = 405; high-dose chemotherapy, n = 399) were included. Median follow-up time was 57 months. Directly after high-dose chemotherapy, HRQOL decreased more compared with conventional chemotherapy for all SF-36 subscales. After 1 year, the reference value of healthy women was reached in b...
    Paclitaxel (Taxol), a new antineoplastic drug, has been reported to be neurotoxic at doses above 200 mg/m2 per course. It is uncertain whether neurotoxicity is related to cumulative amounts of paclitaxel. Neuropathy was prospectively... more
    Paclitaxel (Taxol), a new antineoplastic drug, has been reported to be neurotoxic at doses above 200 mg/m2 per course. It is uncertain whether neurotoxicity is related to cumulative amounts of paclitaxel. Neuropathy was prospectively assessed in 18 patients with breast cancer, receiving between two and eight courses of 135 or 175 mg/m2 of paclitaxel. Vibratory perception thresholds (VPT) and tendon reflex scores were proportionally related to the corresponding cumulative amounts of paclitaxel (P = 0.002; P = 0.0003). The amounts of paclitaxel administered between the first and last assessments (175-1225 mg/m2) were related to concomitant changes in VPT (P = 0.034). Paclitaxel had no clear neurotoxic threshold; if present, it lies below 540 mg/m2. Rather, VPT appeared to increase 0.1 micron per 400 mg/m2 over the entire range of 175-1225 mg/m2 of paclitaxel. Clinical neuropathy prevailed in 0/8 patients at screening and in 5/10 patients at the final assessment (P = 0.029). Neuropathy never exceeded grade 1. Thus, although neurotoxicity of paclitaxel is frequent and cumulative, it remains mild or subclinical up to at least 1400 mg/m2 administered over eight cycles.
    This trial studied the disease-free survival after high-dose chemotherapy in patients in complete remission of metastatic breast cancer. Thirty women, mean age 42.2 years (range 33-55) with metastatic breast cancer, received high-dose... more
    This trial studied the disease-free survival after high-dose chemotherapy in patients in complete remission of metastatic breast cancer. Thirty women, mean age 42.2 years (range 33-55) with metastatic breast cancer, received high-dose chemotherapy in a phase II study. Patients were eligible if they were < or = 55 years of age, had achieved complete remission within 6 months of the initiation of chemotherapy, and had a WHO performance scale of 0 or 1. The high-dose regimen consisted of melphalan 180 mg/m2 and mitoxantrone 60 mg/m2 both divided over 3 days. On day 7 bone marrow and/or peripheral stem cells were infused. After bone marrow recovery, external beam radiation was administered to sites of previous metastatic disease in 15 patients. Apart from leuko- and thrombocytopenia, mucositis was the major side effect. One patient died during the bone marrow transplant period due to an aspergillus infection. The median follow-up since high-dose chemotherapy is 25 months (range 13 to 56 months). The median disease-free survival since high-dose chemotherapy is 27 months and the disease free survival is still 43% with an overall survival of 53% at 3 years. In two patients tumor relapse occurred only in the brain; in one patient the only relapse sign was a meningeal carcinosis. At the moment 17 patients are disease-free (13(+)-56+) months after high-dose chemotherapy. Until now this high-dose regimen in selected patients with complete remission after induction chemotherapy for metastatic breast cancer has a promising disease free survival.
    RESULTS: A median number of six cycles was delivered in both arms, with a median relative dose-intensity of more than 98%. Median time to progression (TTP) and median overall survival (OS) were significantly longer for patients on AT... more
    RESULTS: A median number of six cycles was delivered in both arms, with a median relative dose-intensity of more than 98%. Median time to progression (TTP) and median overall survival (OS) were significantly longer for patients on AT compared with FAC (TTP: 8.0 v 6.6 ...
    Topical treatment of skin metastases with a cytotoxic agent is attractive for its easy self-administration and absence of major systemic interference. Miltefosine exerts its cytotoxicity by acting on cell membrane phospholipids and can be... more
    Topical treatment of skin metastases with a cytotoxic agent is attractive for its easy self-administration and absence of major systemic interference. Miltefosine exerts its cytotoxicity by acting on cell membrane phospholipids and can be administered topically. Twenty breast cancer patients with progression of skin metastases were treated with a 6% solution of miltefosine, which was topically administered once daily during the first week and twice daily thereafter. Sixteen out of 20 patients also had metastatic disease at other sites. Concomitant systemic treatment when ongoing for at least 2 months prior to study entry was permitted, and consisted of chemotherapy and hormonal therapy in seven and nine patients, respectively. Prior palliative cytotoxic and hormonal therapy had been administered to 11 and 19 patients, respectively. No grade 3 and 4 toxicity occurred. Miltefosine therapy was discontinued in two patients due to nausea and in one patient due to skin toxicity. Grade 1 and 2 adverse skin reactions, and nausea and vomiting were seen in 11 and two patients, respectively. In 18 patients evaluable for response, four partial responses were noted (response rate 22%), while seven patients had stable disease. Three partial responses were observed in patients in whom the skin lesions were smaller than 1.5 cm2. Median duration of response was 2.5 months and median time to progression for all patients was 1.9 months. In this study topically applied miltefosine for metastatic skin lesions of breast cancer showed modest activity in a relatively heavily pretreated patient population, without serious systemic toxicity.