Marijke Bontenbal

Risk of endometrial cancer after tamoxifen treatment of breast cancer

Since large trials have been set up to assess whether tamoxifen decreases the risk of breast cancer in healthy women, it has become important to investigate the drugs potential adverse effects, including occurrence of endometrial cancer. We undertook a case-control study in the Netherlands to assess the effect of tamoxifen on the risk of endometrial cancer after breast cancer. Through the population-based Netherlands Cancer Registry and two older, hospital-based, registries, we identified 98 patients who had endometrial cancer diagnosed at least 3 months after a diagnosis of primary breast cancer. Detailed information about treatment was obtained for all these patients, and for 285 controls, who were matched to the cases for age, year of breast cancer diagnosis, and survival time with intact uterus. Tamoxifen had been used by 24% of patients with subsequent endometrial cancer and 20% of controls (relative risk 1.3 [95% CI 0.7-2.4]). Women who had used tamoxifen for more than 2 years had a 2.3 (0.9-5.9) times greater risk of endometrial cancer than never users. There was a significant trend of increasing risk of endometrial cancer with duration of tamoxifen use (p = 0.049), and also with cumulative dose (p = 0.046). The duration-response trends were similar with daily doses of 40 mg or 30 mg and less. These findings support the hypothesis that tamoxifen use increases the risk of endometrial cancer. This oestrogenic effect on the endometrium was not related to the dose intensity. Physicians should be aware of the higher risk of endometrial cancer in tamoxifen users.

Taxanes alone or in combination with anthracyclines as first-line therapy of patients with metastatic breast cancer.

PURPOSE Taxanes (paclitaxel or docetaxel) have been sequenced or combined with anthracyclines (doxorubicin or epirubicin) for the first-line treatment of advanced breast cancer. This meta-analysis uses data from all relevant trials to detect any advantages of taxanes in terms of tumor response, progression-free survival (PFS), and survival. PATIENTS AND METHODS Individual patient data were collected on eight randomized combination trials comparing anthracyclines + taxanes (+ cyclophosphamide in one trial) with anthracyclines + cyclophosphamide (+ fluorouracil in four trials), and on three single-agent trials comparing taxanes with anthracyclines. Combination trials included 3,034 patients; single-agent trials included 919 patients. RESULTS Median follow-up of living patients was 43 months, median survival was 19.3 months, and median PFS was 7.1 months. In single-agent trials, response rates were similar in the taxanes (38%) and in the anthracyclines (33%) arms (P = .08). The hazard ratios for taxanes compared with anthracyclines were 1.19 (95% CI, 1.04 to 1.36; P = .011) for PFS and 1.01 (95% CI, 0.88 to 1.16; P = .90) for survival. In combination trials, response rates were 57% (10% complete) in taxane-based combinations and 46% (6% complete) in control arms (P < .001). The hazard ratios for taxane-based combinations compared with control arms were 0.92 (95% CI, 0.85 to 0.99; P = .031) for PFS and 0.95 (95% CI, 0.88 to 1.03; P = .24) for survival. CONCLUSION Taxanes were significantly worse than single-agent anthracyclines in terms of PFS, but not in terms of response rates or survival. Taxane-based combinations were significantly better than anthracycline-based combinations in terms of response rates and PFS, but not in terms of survival.

Treatment of breast cancer during pregnancy: an observational study

BACKGROUND Little is known about the treatment of breast cancer during pregnancy. We aimed to determine whether treatment for breast cancer during pregnancy is safe for both mother and child. METHODS We recruited patients from seven European countries with a primary diagnosis of breast cancer during pregnancy; data were collected retrospectively if the patient was diagnosed before April, 2003 (when the registry began), or prospectively thereafter, irrespective of the outcome of pregnancy and the type and timing of treatment. The primary endpoint was fetal health for up to 4 weeks after delivery. The registry is ongoing. The study is registered with ClinicalTrials.gov, number NCT00196833. FINDINGS From April, 2003, to December, 2011, 447 patients were registered, 413 of whom had early breast cancer. Median age was 33 years (range 22-51). At the time of diagnosis, median gestational age was 24 weeks (range 5-40). 197 (48%) of 413 women received chemotherapy during pregnancy with a median of four cycles (range one to eight). 178 received an anthracycline, 15 received cyclophosphamide, methotrexate, and fluorouracil, and 14 received a taxane. Birthweight was affected by chemotherapy exposure after adjustment for gestational age (p=0·018), but not by number of chemotherapy cycles (p=0·71). No statistical difference between the two groups was observed for premature deliveries before the 37th week of gestation. 40 (10%) of 386 infants had side-effects, malformations, or new-born complications; these events were more common in infants born before the 37th week of gestation than they were in infants born in the 37th week or later (31 [16%] of 191 infants vs nine [5%] of 195 infants; p=0·0002). In infants for whom maternal treatment was known, adverse events were more common in those who received chemotherapy in utero compared with those who were not exposed (31 [15%] of 203 vs seven [4%] of 170 infants; p=0·00045). Two infants died; both were exposed to chemotherapy and delivered prematurely, but both deaths were thought not to be related to treatment. Median disease-free survival for women with early breast cancer was 70·6 months (95% CI 62·1-105·5) in women starting chemotherapy during pregnancy and 94·4 months (lower 95% CI 64·4; upper 95% CI not yet reached) in women starting chemotherapy after delivery (unadjusted hazard ratio 1·13 [95% CI 0·76-1·69]; p=0·539). INTERPRETATION Although our data show that infants exposed to chemotherapy in utero had a lower birthweight at gestational age than did those who were unexposed, and had more complications, these differences were not clinically significant and, since none of the infants was exposed to chemotherapy in the first trimester, were most likely related to premature delivery. Delay of cancer treatment did not significantly affect disease-free survival for mothers with early breast cancer. Because preterm birth was strongly associated with adverse events, a full-term delivery seems to be of paramount importance. FUNDING BANSS Foundation, Biedenkopf, Germany and the Belgian Cancer Plan, Ministry of Health, Belgium.

Prognosis of Women With Primary Breast Cancer Diagnosed During Pregnancy: Results From an International Collaborative Study

PURPOSE We aimed to determine the prognosis of patients with breast cancer diagnosed during pregnancy (BCP). PATIENTS AND METHODS In this cohort study, a multicentric registry of patients with BCP (from Cancer in Pregnancy, Leuven, Belgium, and GBG 29/BIG 02-03) compiled pro- and retrospectively between 2003 and 2011 was compared with patients who did not have associated pregnancies, using an age limit of 45 years. Patients with a diagnosis postpartum were excluded. The main analysis was performed using Cox proportional hazards regression of disease-free survival (DFS) and overall survival (OS) on exposure (pregnant or not), adjusting for age, stage, grade, hormone receptor status, human epidermal growth factor 2 status, histology, type of chemotherapy, use of trastuzumab, radiotherapy, and hormone therapy. RESULTS The registry contained 447 women with BCP, mainly originating from Germany and Belgium, of whom 311 (69.6%) were eligible for analysis. The nonpregnant group consisted of 865 women. Median age was 33 years for the pregnant and 41 years for the nonpregnant patients. Median follow-up was 61 months. The hazard ratio of pregnancy was 1.34 (95% CI, 0.93 to 1.91; P = .14) for DFS and 1.19 (95% CI, 0.73 to 1.93; P = .51) for OS. Cox regression estimated that the 5-year DFS rate for pregnant patients would have increased from 65% to 71% if these patients had not been pregnant. Likewise, the 5-year OS rate would have increased from 78% to 81%. CONCLUSION The results show similar OS for patients diagnosed with BCP compared with nonpregnant patients. This information is important when patients are counseled and supports the option to start treatment with continuation of pregnancy.

Phase II to III Study Comparing Doxorubicin and Docetaxel With Fluorouracil, Doxorubicin, and Cyclophosphamide As First-Line Chemotherapy in Patients With Metastatic Breast Cancer: Results of a Dutch Community Setting Trial for the Clinical Trial Group of the Comprehensive Cancer Centre

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/m(2) 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 visceral disease compared with FAC patients with visceral disease (59% v 36%, respectively; P = .003). There were no differences in grade 3 to 4 neutropenia and infections (AT 89% v FAC 84% and AT 12% v FAC 9%, respectively). Neutropenic fever was more common in AT-treated patients than FAC-treated patients (33% v 9%, respectively; P < .001). Grade 3 to 4 nonhematologic toxicity was infrequent in both arms. Congestive heart failure was observed in 3% and 6% of patients on AT and FAC, respectively. CONCLUSION In this phase II to III study, AT resulted in a significantly longer TTP and OS and a higher objective ORR than FAC. First-line AT is a valid treatment option for patients with MBC.

Multimodality treatment for anaplastic thyroid carcinoma--treatment outcome in 75 patients.

PURPOSE To retrospectively analyze the outcome of patients with anaplastic thyroid carcinoma (ATC) treated in the Erasmus MC. MATERIAL AND METHODS Seventy-five ATC-patients were treated between 1972 and 2003. Mean age was 68 years. Tumor stage was IVA in 9%, IVB in 51%, and IVC in 40%. Thirty-six patients underwent up-front surgery, with 53% resulting in R0/R1 resection. Before 1988 adjuvant treatment consisted of conventional radiotherapy (RT) and/or chemotherapy (CT). As of 1988, 30 eligible patients were enrolled in a newly designed protocol. This consists of locoregional RT in 46 fractions of 1.1 Gy, given twice daily, followed by prophylactic irradiation of the lungs (PLI) in 5 daily fractions of 1.5 Gy. During radiation, low-dose Doxorubicine (15 mg/m(2)) is administered weekly and is followed by adjuvant Doxorubicine (50 mg/m(2)) 3-weekly up to a cumulative dose of 550 mg/m(2). Twenty-five ineligible patients were treated conventionally. RESULTS Overall median survival was 3 months, 1-year OS 9%. Locoregional control was significantly higher in patients who had undergone R0/R1 resection or chemoradiation, with best results for patients who underwent both (complete remission in 89%). However, the survival benefit of patients who reached CR remained borderline (median OS 7 months, 1-year OS 32%). Three patients survived for more than 5 years; all had undergone R0/R1 surgical resection and chemoradiation. Acute toxicity in the protocol group was significantly higher than in the nonprotocol group, with 46% versus 11% grade 3 pharyngeal and/or esophageal toxicity. CONCLUSION Despite the ultimately dismal prognosis of ATC-patients, multimodality treatment significantly improved local control and improved the median survival.

Molecular subtypes of breast cancer and amplification of topoisomerase IIα: Predictive role in dose intensive adjuvant chemotherapy

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 IIα (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 tumours, 47 (24%) were shown to harbour an amplification of TOP2A. Patients with an HER2-amplified tumour randomised to the high-dose therapy arm did worse than those in the conventional treatment arm, possibly caused by the lower cumulative anthracycline dose in the high-dose arm. The tumours with a TOP2A amplification contributed hardly to this difference, suggesting that TOP2A amplification is not the cause of the steep dose–response curve for anthracyclines in breast cancer. Possibly, the difference of the cumulative dose of only 25% between the treatment arms was insufficient to yield a survival difference.

Altered clearance of unbound paclitaxel in elderly patients with metastatic breast cancer

The pharmacokinetic behaviour of anticancer drugs may be altered with aging due to (for example) differences in body composition and decreased hepatic and renal function. To address this issue for paclitaxel, we studied the pharmacokinetics of the drug in eight elderly women (>or=70 years) with metastatic breast cancer (median age (range), 77 years (70-84 years)) and a control group of 15 patients aged <70 years (median age (range), 54 years (22-69 years)). Paclitaxel was administered as a 1-h intravenous (i.v.) infusion at a dose of 80 (elderly) or 100 mg/m(2) (<70 years), and serial blood samples were obtained at baseline, and up to 24 h after the end of infusion. Paclitaxel concentration-time profiles were fitted to a linear three-compartment model without any demonstration of saturable behaviour. The clearance of unbound paclitaxel was 124+/-35.0 (elderly) versus 247+/-55.4 l/h/m(2) (<70 years) (P=0.002), and was inversely related to the patients age (R(2)=0.857; P<0.00001). Total plasma clearance of the formulation vehicle Cremophor EL (CrEL) was 150+/-60.7 (elderly) versus 115+/-39.2 ml/h/m(2) (<70 years) (P=0.04). These data indicate an approximately 50% change in total body clearance of unbound paclitaxel and a concomitant significant increase in systemic exposure with age, most likely as a result of altered CrEL disposition. The clinical relevance of these observations with respect to toxicity profiles and antitumour efficacy requires further evaluation.

Randomized cross-over evaluation of body-surface area-based dosing versus flat-fixed dosing of paclitaxel.

PURPOSE Despite dose calculation using body-surface area (BSA), pharmacokinetics of most anticancer drugs show wide interindividual variability. In this study, we evaluated the role of BSA in paclitaxel disposition. PATIENTS AND METHODS Paclitaxel pharmacokinetics were prospectively studied in 12 patients that were treated in a randomized cross-over design with paclitaxel (3-hour infusion at a 3-week interval) at 175 mg/m2 in cycle 1 (A) and a flat-fixed dose of 300 mg in cycle 2 (B), or vice versa. Blood samples were collected up to 24 hours after dosing and analyzed for total and unbound paclitaxel. RESULTS The area under the curves (AUC) of unbound paclitaxel were similar in both dosing groups, with mean values +/- SD (A v B) of 1.34 +/- 0.158 versus 1.30 +/- 0.329 microM x h, indicating that BSA-based dosing reduced the coefficient of variation by 53.3%. Unbound and total paclitaxel clearance was also significantly related to various body-size measures, including BSA (R > or = 0.617; P < or =.033), weight (R >or = 0.621; P < or =.031), and lean-body mass (r > or = 0.630; P < or = .028). We hypothesize that this is caused by the association of paclitaxel in the circulation with Cremophor EL, the distribution of which is linked to total blood volume, and thus to BSA. CONCLUSION This study indicates that paclitaxel disposition is significantly related to BSA. This provides a pharmacokinetic rationale for BSA-based dosing of this drug.

The efficacy of taxane chemotherapy for metastatic breast cancer in BRCA1 and BRCA2 mutation carriers

We assessed the efficacy of taxane chemotherapy in BRCA1‐ and BRCA2‐associated patients compared with sporadic metastatic breast cancer patients.