Bone mineral density in breast cancer patients treated with adjuvant letrozole, tamoxifen, or sequences of letrozole and tamoxifen in the BIG 1-98 study (SAKK 21/07).

BACKGROUND: The risk of osteoporosis and fracture influences the selection of adjuvant endocrine therapy. We analyzed bone mineral density (BMD) in Swiss patients of the Breast International Group (BIG) 1-98 trial [treatment arms: A, tamoxifen (T) for 5 years; B, letrozole (L) for 5 years; C, 2 years of T followed by 3 years of L; D, 2 years of L followed by 3 years of T]. PATIENTS AND METHODS: Dual-energy X-ray absorptiometry (DXA) results were retrospectively collected. Patients without DXA served as control group. Repeated measures models using covariance structures allowing for different times between DXA were used to estimate changes in BMD. Prospectively defined covariates were considered as fixed effects in the multivariable models. RESULTS: Two hundred and sixty-one of 546 patients had one or more DXA with 577 lumbar and 550 hip measurements. Weight, height, prior hormone replacement therapy, and hysterectomy were positively correlated with BMD; the correlation was negative for letrozole arms (B/C/D versus A), known osteoporosis, time on trial, age, chemotherapy, and smoking. Treatment did not influence the occurrence of osteoporosis (T score < -2.5 standard deviation). CONCLUSIONS: All aromatase inhibitor regimens reduced BMD. The sequential schedules were as detrimental for bone density as L monotherapy.

Differential efficacy of three cycles of CMF followed by tamoxifen in patients with ER-positive and ER-negative tumors: long-term follow up on IBCSG Trial IX.

BACKGROUND: The benefit of adjuvant chemotherapy in postmenopausal patients with estrogen receptor (ER)-positive lymph node-negative breast cancer is being reassessed. PATIENTS AND METHODS: After stratification by ER status, 1669 postmenopausal patients with operable lymph node-negative breast cancer were randomly assigned to three 28-day courses of 'classical' CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy followed by tamoxifen for 57 months (CMF→tamoxifen) or to tamoxifen alone for 5 years. RESULTS: ERs were positive in 81% of tumors. At a median follow-up of 13.1 years, patients with ER-positive breast cancers did not benefit from CMF [13-year disease-free survival (DFS) 64% CMF→tamoxifen, 66% tamoxifen; P = 0.99], whereas CMF substantially improved the prognosis of patients with ER-negative breast cancer (13-year DFS 73% versus 57%, P = 0.001). Similarly, breast cancer-free interval (BCFI) was identical in the ER-positive cohort but significantly improved by chemotherapy in the ER-negative cohort (13-year BCFI 80% versus 63%, P = 0.001). CMF had no influence on second nonbreast malignancies or deaths from other causes. CONCLUSION: CMF is not beneficial in postmenopausal patients with node-negative ER-positive breast cancer but is highly effective within the ER-negative cohort. In the future, other markers of chemotherapy response may define a subset of patients with ER-positive tumors who may benefit from adjuvant chemotherapy.

Is chemotherapy alone adequate for young women with oestrogen-receptor-positive breast cancer?

BACKGROUND: The prognosis of breast cancer in very young women is generally considered to be unfavourable. Therefore, the outcome of adjuvant therapy was analysed in a population of young (<35 years) premenopausal patients treated in four randomised controlled trials. METHODS: Between 1978 and 1993 the International Breast Cancer Study Group (IBCSG) treated 3700 premenopausal and perimenopausal patients with various timing and duration of adjuvant cyclophosphamide, methotrexate, and fluorouracil (CMF with or without low-dose prednisone and oophorectomy). 314 of these women were less than 35 years old at randomisation. FINDINGS: Relapse and death occurred earlier and more often in younger (<35 years) than in older (> or = 35) patients with a 10 year disease-free survival of 35% (SE 3) versus 47% (1) (hazard ratio 1.41 [95% CI 1.22-1.62], p<0.001) and overall survival of 49% (3) versus 62% (1) (1.50 [1.28-1.77], p<0.001). Younger patients with oestrogen-receptor positive tumours had a significantly worse disease-free survival than younger patients with oestrogen-receptor negative tumours. By contrast, among older patients the disease-free survival was similar irrespective of oestrogen-receptor status. INTERPRETATION: Young premenopausal breast cancer patients treated with adjuvant CMF chemotherapy had higher risk of relapse and death than older premenopausal patients, especially if their tumours expressed oestrogen receptors. The endocrine effects of chemotherapy alone are insufficient for the younger age group and these patients should strongly consider additional endocrine therapies (tamoxifen or ovarian ablation) if their tumours express oestrogen receptors.

High-dose intravenous glutathione in man. Pharmacokinetics and effects on cyst(e)ine in plasma and urine.

Parenteral glutathione has therapeutic potential for targeted delivery of cysteine equivalents. Thus, high doses of reduced glutathione (GSH) protect from the nephrotoxic and urotoxic effects of cisplatinum and oxazaphosphorines. In order to elucidate the underlying mechanisms the kinetics and the effect of glutathione on plasma and urine sulphydryls were studied in 10 healthy volunteers. Following the intravenous infusion of 2 g m-2 of glutathione the concentration of total glutathione in plasma increased from 17.5 +/- 13.4 mumol l-1 (mean +/- SD) to 823 +/- 326 mumol l-1. The volume of distribution of exogenous glutathione was 176 +/- 107 ml kg-1 and the elimination rate constant was 0.063 +/- 0.027 min-1 corresponding to a half-life of 14.1 +/- 9.2 min. Cysteine in plasma increased from 8.9 +/- 3.5 mumol l-1 to 114 +/- 45 mumol l-1 after the infusion. In spite of the increase in cysteine, the plasma concentration of total cyst(e)ine (i.e. cysteine, cystine, and mixed disulphides) decreased, suggesting an increased uptake of cysteine from plasma into cells. Urinary excretion of glutathione and of cyst(e)ine was increased 300-fold and 10-fold, respectively, in the 90 min following the infusion. The present data suggest that the concentration of sulphydryls in the urinary tract and, more importantly, the intracellular availability of cysteine increase markedly following parenteral glutathione. The high intracellular concentration of cysteine may protect against cisplatinum and oxazaphosphorine toxicity either directly or indirectly by supporting the synthesis of glutathione.