Cyclical etidronate increases bone density in the spine and hip of postmenopausal women receiving long term corticosteroid treatment. A double blind, randomised placebo controlled study. (1/313)

OBJECTIVE: To study the effect of cyclic etidronate in secondary prevention of corticosteroid induced osteoporosis. METHODS: A double blind, randomised placebo controlled study comparing cyclic etidronate and placebo during two years in 37 postmenopausal women receiving long term corticosteroid treatment, mainly for polymyalgia rheumatica (40% of the patients) and rheumatoid arthritis (30%). Bone density was measured in the lumbar spine, femoral neck, and femoral trochanter. RESULTS: After two years of treatment there was a significant difference between the groups in mean per cent change from baseline in bone density in the spine in favour of etidronate (p = 0.003). The estimated treatment difference (mean (SD)) was 9.3 (2.1)%. Etidronate increased bone density in the spine (4.9 (2.1)%, p < 0.05) whereas the placebo group lost bone (-2.4 (1.6)%). At the femoral neck there was an estimated difference of 5.3 (2.6)% between the groups (etidronate: 3.6% (1.4)%, p < 0.05, placebo: -2.4 (2.1)%). The estimated difference at the trochanter was 8.2 (3.0) (etidronate: 9.0 (1.5)%, p < 0.0001, placebo: 0.5 (2.3)%). No significant bone loss occurred in the hip in placebo treated patients. CONCLUSIONS: Cyclic etidronate is an effective treatment for postmenopausal women receiving corticosteroid treatment and is well tolerated.  (+info)

186Re-etidronate in breast cancer patients with metastatic bone pain. (2/313)

The aim of this study was to evaluate the efficacy of 186Re-1,1-hydroxyethylidene diphosphonate (etidronate) in breast cancer patients with painful bone metastases. METHODS: Thirty patients with advanced breast cancer who had metastatic bone pain were treated with 186Re-etidronate using different dosages in a noncomparative, open-label study. Twenty-four patients were evaluated for efficacy (6 patients had incomplete datasets). Dosages varied from 1295 to 2960 MBq (35 to 80 mCi). Efficacy was evaluated according to the multidimensional pain model using a paper-and-pencil diary. The diary was kept twice daily for 8-10 wk (2 wk before through 6-8 wk after 186Re-etidronate treatment). Response was determined with a strict criteria, in which pain intensity (PI), medication index (MI) and daily activities (DA) were core determinants. Response was defined as: (a) Reduced PI > or = 5% while MI and DA were at least constant; or (b) Reduced PI <25% in combination with improvement of MI or DA > or = 25%, without worsening of either factor. Duration of response should always exceed a minimum of 2 wk. RESULTS: Fifty-eight percent (n = 14) of all patients reported a response. The maximum follow-up period was 8 wk. Duration of response ranged from 2 to 8 wk (mean 4 wk). Patients (14/24) not only experienced considerable pain reduction, but in 12 patients this was also accompanied by noteworthy reduction in MI (> or = 25%). No clear dose-response relationship was found. CONCLUSION: With strict pain assessment criteria, 186Re-etidronate showed a response of 58% in the palliative treatment of metastatic bone pain originating from breast cancer.  (+info)

Combination 186Re-HEDP and cisplatin supra-additive treatment effects in prostate cancer cells. (3/313)

Radionuclide therapy has proven to be an efficacious palliative treatment for metastatic prostate cancer. Its potential therapeutic possibilities may be substantially increased by combining it with effective radiosensitizing drugs. METHODS: This study explores the radiosensitizing properties of cisplatin when combined with 186Re-labeled hydroxyethylidene diphosphonate (HEDP) in the treatment of R3327-MATLyLu prostate cancer cells in vitro. A concomitant incubation during 4 d, combining various concentrations of cisplatin (0, 0.42, 0.83 and 1.67 micromol/L) and 186Re-HEDP (0, 1.84 and 3.69 MBq/mL [0, 50 and 100 microCi/mL, respectively]) was followed by the determination of the cell numbers surviving and the replating of these cells in semisolid agar. RESULTS: The surviving fraction of clonogenic tumor cells after combination treatment clearly showed synergism when analyzed by a panel of three different published analytical methods. In addition, analysis of variance demonstrated a significant interaction between radionuclide therapy and cisplatin-based chemotherapy (P < 0.001). Treatment with 186Re-HEDP and cisplatin by sequential incubation yielded similar, but never superior results. CONCLUSION: It is concluded that radionuclide therapy in combination with cisplatin is able, in principle, to improve therapeutic success rate in metastatic prostate cancer in a more than additive way.  (+info)

Evidence for the promotion of bone mineralization by 1alpha,25-dihydroxycholecalciferol in the rat unrelated to the correction of deficiencies in serum calcium and phosphorus. (4/313)

Concurrent administration of 1alpha,25-dihydroxycholecalciferol [1alpha,25-(OH)2-CC] to intact and thyroparathyroidectomized rats treated with ethane-1-hydroxy-1,1-diphosphonate (EHDP) prevented or reversed the EHDP-induced inhibition of bone mineralization as measured by changes in epiphyseal plate width and ash content of bone. An analog, 1alpha-droxycholecalciferol, was also effective. Recovery of bone after EHDP treatment was also significantly improved by administration of 1alpha,25-(OH)2-CC as evidenced by enhanced uptake of 45Ca by epiphyseal plates and decreased plate widths. Cholecalciferol (CC), ergocalciferol, dihydrotachysterol2, 5,6-trans-CC, 25-OH-CC, 5,6-Trans-25-OH-CC, and 1alpha24R,25-(OH)3-CC also blocked EHDP-induced epiphyseal plate widening, but required high, pharmacological dose levels. 24R,25- (OH)2-CC was inactive at doses up to 10 microgram/day. Since EHDP-treated rats are not deficient in calcium or phosphate, these data suggest that 1alpha,25-dihydroxycholecalciferol promoted bone mineralization independently of effects upon the intestinal absorption of calcium and phosphate.  (+info)

Skeletal effects of constant and terminated use of sodium risedronate in ovariectomized rats. (5/313)

AIM: To study the skeletal effects of constant and terminated use of sodium risedronate (Ris) treatment in the ovariectomized (Ova) rats. METHODS: Ris 5, s.c., twice a wk. The proximal tibial metaphysis (PTM) were processed undecalcified for quantitive bone histomorphometry. RESULTS: (1) Placebo-treated (normal saline) Ova rats were characterized by decreased trabecular area (TA) on d 60, d 81, and d 150 compared with aging controls, and bone resorption was over formation with high bone turnover. (2) Ova rats were treated with Ris for 60, 81, and 150 d (Ris-on) increased. (TA 217%, 108%, and 101%) respectively, vs Ova rats and depressed bone turnover indices to aging control level, but bone mass did not maintain at high level in 150-d group as in the early stage. (3) Ova rats were pretreated with Ris for 60 d and then terminated (Ris-on/off), followed by sequential sacrifice of rats on 21 and 90 d. Withdrawal on 21 d showed the same results as the match-age Ris-on group. Withdrawal on 90 d still maintained cancellous bone mass at a high level vs 150 d Ris-on groups (+26%) and aging control group (+27%). CONCLUSION: Regimen of Ris 60 d on then 90 d off prevented the development of osteoporosis in Ova rats.  (+info)

Rhenium-186-labeled hydroxyethylidene diphosphonate dosimetry and dosing guidelines for the palliation of skeletal metastases from androgen-independent prostate cancer. (6/313)

Rhenium-186 (tin)-labeled hydroxyethylidene diphosphonate (186Re-labeled HEDP) was evaluated in 27 men with progressive androgen-independent prostate cancer and bone metastases. Administered activities ranged from 1251 to 4336 MBq (33.8-117.2 mCi). The primary objectives were to assess tumor targeting, normal organ dosimetry, and safety. Antitumor effects were assessed by posttherapy changes in prostate-specific antigen and, when present, palliation of pain. Whole-body kinetics, blood and kidney clearance, skeletal dose, marrow dose, and urinary excretion of the isotope were assessed. Targeting of skeletal disease was observed over the period of quantification (4-168 h). Radiation doses to whole body, bladder, and kidney were well tolerated. The dose-limiting toxicity was myelosuppression (grade III) at 4107 MBq (111 mCi) and grade II at 296 MBq (80 mCi). Probe clearance (whole body) and urinary excretion measurements were highly correlated. Of the six patients treated at the highest dosage schedules (three at 1510 MBq/m2 and three at 1665 MBq/m2), three showed a posttherapy decline in prostate-specific antigen of 50% or more. The declines were not sustained. The determination of total activity retained at 24 h, as well as an estimate of marrow dose, correlated with the amount of myelosuppression observed. These results suggest that a single 24-h measurement of retained activity would allow individualized dosing and an improved therapeutic index relative to fixed dosing schema. Repetitive dosing is required to increase palliation.  (+info)

Intermittent inhibition of dentin mineralization of rat incisors under continual infusion of 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) using a subcutaneous mini osmotic pump. (7/313)

The inhibitory effect of the continual administration of 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) (8 mgP/kg/day) through a mini osmotic pump on dentin mineralization was examined in relation to the diurnal rhythm of the rat and compared with that of daily injections of same amounts of HEBP known to inhibit dentin mineralization. After daily injections of HEBP, a series of alternating rows of mineralized and non-mineralized dentin islands appeared in the newly formed portion of the crown-analogue of rat incisors. A similar phenomenon occurred under the continual administration of HEBP in rats raised either under regular environmental photofraction or constant lighting conditions. The average distance between the adjacent mineralized dentin islands was 521.0 +/- 51.3 microns in the injected rats. After continual HEBP administration, this was 426.0 +/- 13.2 microns and 416.5 +/- 19.4 microns under ordinary photofraction and constant light, respectively. Although the pattern of individual mineralized dentin islands tended to become irregular in nocturnal rats, no statistical difference was noted between the two values. Rows of mineralized and non-mineralized dentin islands also appeared in the root analogue dentin. No sign of the intermittent inhibition of mineralization was recognized in mesodermal hard tissues other than dentin in the HEBP-affected animals. These data implicate the presence of intrinsic cycles in dentin mineralization at the growing end of rat incisors independent of environmental photofraction as well as the ameloblast function.  (+info)

Bone scintigraphy in renal osteodystrophy. (8/313)

Bone scintigraphy with Tc-99m HEDP was performed in 30 patients on maintenance hemodialysis, and the results of quantitative analysis were compared with those of a normal group. To permit this comparison, elevated background activity due to the absence of renal radiotracer excretion was reduced by hemodialysis to levels found in the normals. Histologic proof of renal osteodystrophy had been obtained in all patients. The incidence of radiographic abnormalities was 46%, whereas abnormal scans were found in 25 patients (83%); skeletal lesions were also more pronounced and detected earlier. However, even when the scans appeared normal, the quantitative analysis showed increased skeletal activity in all patients. The total skeletal activity proved to be a good index of the severity of renal osteodystrophy and appeared dependent on both osteomalacia and hyperparathyroidism. These findings show that bone scintigraphy is a sensitive method to detect skeletal involvement in renal osteodystrophy.  (+info)