Renal safety profiles of ibandronate 6 mg infused over 15 and 60 min: a randomized, open-label study.

BACKGROUND: Clinical data show that a single, 15-min i.v. infusion of ibandronate 6 mg does not significantly alter renal function. We evaluated the effect on renal function of repeated 15-min infusions of ibandronate 6 mg in women with breast cancer and bone metastases. PATIENTS AND METHODS: Patients were randomly assigned to i.v. ibandronate 6 mg every 3-4 weeks for < or =6 months, infusion over 15 min (n = 102) or 60 min (n = 28). The primary end point was the percentage of patients with increased serum creatinine of > or =44.2 micromol/l. Blood chemistry was assessed at each visit. RESULTS: Two per cent [2/101; 95% confidence interval (CI) 0.2-7.0] of patients in the 15-min infusion arm and no patients (0/26; 95% CI 0.0-13.2) in the 60-min infusion arm had increased serum creatinine that met the primary end point. There were no clinically relevant changes in serum creatinine, creatinine clearance, or N-acetyl-beta-d-glucosaminidase, alpha(1)-microglobulin, or microalbuminuria. Most adverse events were mild or moderate. No clinically relevant changes were observed in vital signs, hematology, blood chemistry, or urine analysis. CONCLUSIONS: Ibandronate 6 mg by 15-min infusion every 3-4 weeks appear to be consistent with those renal safety profiles of 60-min infusion.

Randomized phase II trial comparing different doses of the bisphosphonate ibandronate in the treatment of hypercalcemia of malignancy.

PURPOSE: To evaluate the hypocalcemic effect and safety of three different doses of the bisphosphonate ibandronate in tumor-associated hypercalcemia, and to identify factors predicting response. PATIENTS AND METHODS: One hundred seventy-four cancer patients with a serum calcium level greater than 2.7 mmol/L (10.8 mg/dL) were enrolled onto the trial. If hypercalcemia persisted after fluid repletion, patients were randomly assigned to treatment with 0.6 mg, 1.1 mg, and 2.0 mg of ibandronate. Response, defined as restoration of normocalcemia, was evaluated by an intent-to-treat analysis. RESULTS: One hundred seventy-three (99%) patients were assessable for toxicity and 151 (87%) for efficacy. The administration of 0.6 mg (group A), 1.1 mg (group B), or 2.0 mg (group C) of ibandronate led to response rates of 44%, 52%, and 67%, respectively. Significantly more patients in group C responded than in group A (P = .0276). Of the various parameters examined, only the initial serum calcium level (P < .0001; odds ratio, 0.083) and the dose of ibandronate (P = .0162; odds ratio, 2.094) correlated with response. One hundred ninety-five adverse events (AEs) were reported, 99 classified as serious and 96 as nonserious. Three serious and sixteen nonserious AEs were considered related to ibandronate treatment. The three serious AEs were one case with thrombocytopenia, one with nausea, and one with fever. CONCLUSION: Ibandronate therapy led to a dose-dependent reduction in serum calcium levels. The response to ibandronate treatment correlated negatively with the initial serum calcium level and positively with the dose administered. A dose of 2 mg was necessary to achieve a response rate comparable to that in previous studies with the bisphosphonates pamidronate and clodronate. Because the incidence of drug-associated AEs was low, a dose escalation of ibandronate can be recommended for further clinical trials.

Serum bone sialoprotein in patients with primary breast cancer is a prognostic marker for subsequent bone metastasis.

Bone sialoprotein (BSP) is a noncoflagenous bone matrix protein that is important for both mineralization and cell-cell interactions. Tissue studies in primary breast cancers have shown that immunohistochemical expression of BSP is associated with a high incidence of bone metastases in the course of the disease. We used a RIA to investigate the importance of serum BSP as a marker for subsequent bone metastases. Between 1994 and 1996, preoperative blood samples were collected from 388 consecutive patients with nonmetastatic breast cancer and from 30 control patients with benign breast disease. Serum BSP concentrations were measured in a blinded fashion by RIA. The cutoff for elevated serum BSP values was 24 ng/ml, ie., two SDs above the normal mean value. Serum BSP was correlated with the risk of metastasis and analyzed with regard to its prognostic value. After a median follow-up period of only 20 months, 28 patients had developed metastases. Fourteen patients had bone metastases only, 9 visceral metastases only, and 5 a combination of osseous and visceral metastases. Of the 19 women with skeletal metastases, 17 had preoperative serum BSP values in excess of 24 ng/ml (median BSP values: 48.3 ng/ml for isolated metastatic bone disease, 30.6 ng/ml for combined metastases), whereas none of the women with visceral metastases only had elevated serum BSP concentrations (median BSP value: 12.3 ng/ml). The median serum BSP value in the control group (benign breast disease) was 8.8 ng/ml serum BSP; levels correlated with the size of the primary tumor, but not with any other prognostic factors. Using a multivariate regression analysis, serum BSP was found to be the most important independent prognostic factor for the development of skeletal metastasis (P < 0.001; relative risk, 94); its specificity was 96.7%, and its sensitivity was 89.5%. Our study shows that patients with preoperatively elevated serum BSP levels are at high risk of subsequent bone metastases in the first years after primary surgery. The mechanism of BSP in the pathogenesis of skeletal metastases is unclear. Because BSP contains an integrin recognition sequence, its expression in tumor cells may facilitate their adhesion to the bone surface. However, it is possible that a proportion of circulation BSP is derived from normal or tumor-induced bone turnover. Breast cancer patients with elevated serum BSP levels may benefit from osteoprotective adjuvant therapy with bisphosphonates.

Effect of first treatment with aminobisphosphonates pamidronate and ibandronate on circulating lymphocyte subpopulations.

Up to 60% of patients receiving their first infusion of the bisphosphonate pamidronate experience an acute-phase reaction. In this study, we used flow cytometry to determine the effects of pamidronate treatment on circulating lymphocyte subpopulations, and we investigated whether pamidronate and ibandronate treatment affect lymphocyte subpopulations differently. Twenty patients received a pamidronate infusion, 20 patients received intravenously injected ibandronate, and 10 controls received a clodronate infusion. Pamidronate treatment was followed by a significant increase in median body temperature at the 10-hour measurement and a significant decrease in counts of circulating lymphocytes, natural killer cells, T cells, and CD4+ and CD8+ T-cell subsets. Ibandronate treatment did not affect median body temperature, and it was associated at the 10-hour measurement with maximum increases in total lymphocyte count, B cells, T cells, and CD4+ and CD8+ T-cell subsets. Thus, there is a substantial difference in the hematologic response to initial treatments with pamidronate and ibandronate. Clodronate treatment did not induce changes in body temperature or significantly affect the number of circulating T cells and NK cells. The reduction in lymphocyte subsets after initial pamidronate therapy might be mediated by the release of tumor necrosis factor alpha, whose source in the acute-phase reaction could be T cells.

Administration of the bisphosphonate ibandronate (BM 21.0955) by intravenous bolus injection.

Bisphosphonates (BPs) are used for the treatment of both benign and malignant diseases characterized by increased bone resorption. Because of their potential nephrotoxicity, currently available BPs have to be administered by slow intravenous infusion, with conventional doses requiring an infusion time of at least 2 h. In the present investigation, we evaluated the safety and efficacy of the new BP ibandronate as administered by intravenous bolus injection. On day 0, 15 normocalcemic breast cancer patients with bone metastases were treated with 3 mg of ibandronate injected intravenously over 60-120 s. Ibandronate treatment led to significant decreases in serum levels of calcium (p < 0.0001) and phosphate (p < 0.0001) and to subsequent increases in serum concentrations of parathyroid hormone (p <0.0001) and calcitriol (p <0.0001). Moreover, there was a significant reduction in the urinary excretion of calcium (p <0.0001), pyridinoline (p <0.001), and deoxypyridinoline (p < 0.0001). Three serious adverse events were observed: vomiting (WHO grade 3), pulmonary infection (WHO grade 2), and deterioration of a pre-existing impaired glucose tolerance (WHO grade 3). Only vomiting appeared to be related to administration of the drug. The most frequent nonserious adverse events were 10 cases of transient clinically asymptomatic hypocalcemia and 8 cases of asymptomatic hypophosphatemia. Serum levels of creatinine and urea nitrogen did not increase, nor did creatinine clearance deteriorate. When tested with the dipstick method, proteinuria was present in five (33%) patients prior to ibandronate treatment (median protein concentration, 30 mg/dl). Following the BP injection, seven (47%) patients showed slight (highest protein concentration, 30 mg/dl) transient proteinuria at at least one time point, of which six cases appeared in conjunction with leucocyturia and three with microhematuria. Side effects specific to aminosubstituted BPs (fever, reduction in white blood cell counts, and lymphocyte counts) were not seen in these 15 patients. In conclusion, a single intravenous injection of 3 mg of ibandronate significantly inhibited osteoclast activity as reflected by the decrease in serum calcium and in urinary parameters of bone resorption. Serum creatinine levels and estimates of creatinine clearance were not affected by therapy. However, before repeated bolus injections of ibandronate at this dosage can be recommended for further clinical trials, whether a relationship exists between the transient pathological urinary findings and injected ibandronate needs to be determined.

Novel serum markers of bone resorption: clinical assessment and comparison with established urinary indices.

Although urinary measurements of collagen degradation provide valid estimates of bone resorption, their clinical application is hampered by pronounced analytical and biological variability. Therefore, immunoassays for the determination of such parameters in serum have been developed. In this study, we assessed the performance of three new serum markers of bone turnover, i.e., C-terminal and N-terminal telopeptides of type I collagen (S-CTX and S-NTX) and bone sialoprotein. Results were compared with urinary total pyridinoline, total deoxypyridinoline, and urinary C-terminal telopeptides of type I collagen (U-CTX) and urinary N-terminal telopeptides of type I collagen (U-NTX). The study population included healthy men (n = 27), premenopausal (n = 30) and postmenopausal (n = 31) women, patients with hepatic dysfunction (HF, n = 24), renal failure (RF, n = 30), breast cancer without (BC-, n = 24) and with (BC+, n = 30) bone metastases, primary vertebral osteoporosis (OPO, n = 27), primary hyperparathyroidism (PHPT, n = 16), active Paget's disease of bone (n = 18), multiple myeloma (MM, n = 18), and patients with hypercalcemia of malignancy before and after treatment with pamidronate (HOM, n = 28). Changes in urinary and serum markers were similar in most metabolic bone diseases. However, differentiation between healthy controls and OPO, or PHPT, was improved by the serum markers. In MM, all serum and urinary markers were elevated (p < 0. 05 vs. controls). In BC+, skeletal involvement was reflected by significant increments in all indices (p < 0.01 vs. BC-), except U-CTX and S-CTX. In HOM, pamidronate-induced changes in biomarkers were most pronounced for U-CTX and S-CTX and S-NTX. HF and RF were associated with elevated levels of all serum markers (p < 0.05 vs. controls). In conclusion, measurements in serum reflect bone resorption to the same extent as the urinary indices. Since serum markers circumvent some of the limitations of urinary measurements, their use potentially improves the assessment of skeletal disorders.

Parathyroid hormone-related protein and life expectancy in hypercalcemic cancer patients.

We determined the effect of raised serum levels of midregional (53-84) parathyroid hormone-related protein (PTHrP) on life expectancy in 59 cancer patients with first presentation of hypercalcemia. The patients were stratified according to the serum PTHrP levels measured on day 0 after fluid repletion prior to bisphosphonate therapy. Twenty-nine patients were assigned to group N (PTHrP < or = 21 pmol/L) and 30 to group E (PTHrP > 21 pmol/L). Breast cancers were more common in group N, squamous cell cancers predominated in group E (p < 0.02). More patients with normal PTHrP had skeletal metastases, whereas group E was characterized by a higher incidence of prognostically unfavorable visceral involvement (p < 0.001). Bisphosphonates (pamidronate or BM.210955) were administered on day 0. Within one week, normocalcemia (serum calcium < or = 2.6 mmol/L) was restored in 96% of patients in group N, compared to 70% of patients in group E (p < 0.01). On day 12, 7 patients with elevated PTHrP were still hypercalcemic. Although a comparable number of patients in the two groups received cytostatic treatment after day 12, objective tumor responses were seen only in group N (n = 6; p < 0.05). Calculated from the first occurrence of hypercalcemia, the median survival was 66 days in group N and 33 days in group E (log-rank test: p = 0.0456; Wilcoxon-Breslow test: p = 0.0475). We conclude that in hypercalcemia of malignancy raised serum levels of PTHrP indicate a reduced hypocalcemic response to bisphosphonates, a more advanced tumor state and, therefore, an extremely poor prognosis.

Parathyroid hormone-related protein (PTHrP) does not regulate 1,25-dihydroxyvitamin D serum levels in hypercalcemia of malignancy.

We investigated in humoral hypercalcemia of malignancy whether parathyroid hormone-related protein (PTHrP) elevation causes a rise in 1,25-dihydroxyvitamin D (1,25-(OH)2 D) serum levels. We assessed 41 patients with hypercalcemia of malignancy in a prospective study. There were 19 patients who had serum PTHrP levels in the normal range; 22 patients had elevated serum PTHrP levels. All patients were treated with the bisphosphonate pamidronate resulting in a drop of serum calcium (p < 0.0001) and serum phosphate (p < 0.0023) within 12 days, independent of the group. Parathyroid hormone (PTH) was suppressed at the start of therapy and rose to within the normal range during therapy (p < 0.0001), regardless of the PTHrP levels. PTHrP levels were not influenced by calcium lowering therapy. The serum levels of 1,25-(OH)2 D were either suppressed or in the low normal range at the beginning of the study, without any significant difference between both groups. All patients showed a rise in 1,25-(OH)2 D during bisphosphonate therapy (p < 0.0001), independent of their PTHrP levels. Thus PTHrP did not influence the calcium, phosphate-, or PTH-dependent regulation of 1,25-(OH)2 D during calcium lowering therapy. We conclude, that PTHrP does not stimulate renal 1-hydroxylase activity in humoral hypercalcemia of malignancy.

The diagnostic value of urinary pyridinium cross-links of collagen, serum total alkaline phosphatase, and urinary calcium excretion in neoplastic bone disease.

Bone metastases strongly affect skeletal metabolism by both their growth and their paracrine activities. However, so far no specific laboratory marker has been found to signal the spread of neoplastic disease to bone. We performed a cross-sectional study of 153 cancer patients and an equal number of healthy controls matched for sex and age, in which we determined serum levels of calcium and total alkaline phosphatase (TAP) as well as the fasting urinary excretion of calcium (uCa) and of the collagen cross-links pyridinoline (uPYD) and deoxypyridinoline (uDPD). The aim of the study was to analyze the diagnostic validity of the biochemical parameters measured with regard to neoplastic bone involvement. In the cancer group, 98 patients had overt bone metastases, as judged from radiographic and radioisotopic bone imaging. The remaining 55 patients were also in an advanced stage of disease, but there was no evidence of malignant bone involvement. In comparison to healthy controls, patients both with and without metastatic bone disease had significantly higher levels of TAP, uPYD, and uDPD (P < 0.0001). Only in cancer patients with bone metastases was the median serum calcium level higher than in the healthy controls (P < 0.02). uCa was the same in cancer patients and the control group. Within the collective of cancer patients, individuals with skeletal metastases had higher levels of serum calcium (P < 0.05), TAP (P < 0.01), and uPYD and uDPD (both P < 0.0001), than patients without evidence of malignant bone disease. uCa did not differ between the 2 groups of cancer patients. The cancer patients were then stratified into 4 subgroups according to the serum calcium level (< or = 2.6 mmol/L >) and the absence or evidence of bone metastases. This stratification revealed that in patients with bone metastases, uPYD and uDPD levels were similar in normocalcemic and hypercalcemic subjects, whereas in hypercalcemic patients, uCa levels significantly exceeded those in normocalcemic patients. When the efficacy of TAP, uCa, uPYD, and uDPD in discriminating between patients with and without bone metastases was evaluated by use of receiver-operating characteristic curves and stepwise multivariate regression analysis, uPYD was found to have the highest diagnostic validity. Using 50 mumol PYD/mol creatinine (i.e. the upper limit of normal range) as the cut-off level, the sensitivity of uPYD was 88.7%, whereas the specificity was only 41.8% (odds ratio, 5.598; 95% confidence interval, 2.547-12.306).(ABSTRACT TRUNCATED AT 400 WORDS)

Serum immunoreactive bone sialoprotein as a new marker of bone turnover in metabolic and malignant bone disease.

Bone sialoprotein (BSP) is a phosphorylated glycoprotein with a M(r) of 70-80 kDa that accounts for approximately 5-10% of the noncollagenous proteins of bone. Due to its relatively restricted distribution to mineralized tissues, BSP may serve as a potential marker of bone metabolism. Employing a recently developed RIA, serum BSP was measured in 133 healthy subjects, aged 20-80 yr, and in patients with primary hyperparathyroidism (pHPT; n = 26), Paget's disease of bone (PD; n = 14), untreated multiple myeloma (MM; n = 32), and breast cancer with bone metastases (BC; n = 19). Results were compared to clinical and laboratory data, including serum total alkaline phosphatase as a marker of bone formation, and the urinary cross-links pyridinoline (PYD) and deoxypyridinoline (DPD) as markers of bone resorption. In healthy adults, serum BSP values ranged between 5.0-21.6 ng/mL (5-95% interval), with a median of 10.5 ng/mL (total group). In healthy females, a linear correlation was found between serum BSP and age (r = 0.51; P < 0.001), with significantly higher values in postmenopausal than in premenopausal women (13.3 +/- 4.8 vs. 9.0 +/- 3.8; P < 0.01). In the healthy group, BSP values did not change with body mass index, lumbar bone mineral density, serum calcium, serum creatinine, or serum total alkaline phosphatase levels. In contrast, a weak, but significant, correlation was observed between serum BSP and the urinary excretion of PYD and DPD. Compared to those in healthy controls, serum BSP levels were significantly higher in patients with pHPT, PD, MM, or BC (P < 0.01 for all groups). These differences remained after analyses were adjusted for age and sex. In pHPT, serum BSP levels were closely correlated to urinary PYD and DPD (r = 0.87 and 0.83, respectively; P < 0.01), whereas in PD, no correlation was observed between any of the bone markers. Serum BSP levels were highest in patients with MM, and there was a significant difference between early and advanced stages of the disease (30.2 +/- 8.0 vs. 64.3 +/- 6.8; P < 0.01). In a subgroup of 15 patients with metastatic BC, iv bisphosphonate treatment resulted in a rapid reduction of serum BSP levels to 40% of the baseline values within 4 days of treatment. In conclusion, BSP appears to be a sensitive marker of bone turnover, and the present data suggest that its serum levels predominantly reflect processes related to bone resorption.

Serum parathyroid hormone-related protein levels and response to bisphosphonate treatment in hypercalcemia of malignancy.

The pathogenesis of hypercalcemia of malignancy comprises increased net bone resorption and enhanced renal tubular reabsorption of calcium (Ca). To evaluate the prevalence of an increased renal tubular reabsorption of Ca index [tubular reabsorption of calcium index (TRCaI)] in cancer patients with hypercalcemia and of elevated circulating levels of PTH-related protein (PTHrP), which is recognized as a major mediator of this syndrome, we investigated 315 well rehydrated patients, aged 58.1 +/- 0.7 yr (mean +/- SEM), with hypercalcemia [albumin-corrected plasma Ca (pCa), >2.7 mmol/L] secondary to histologically proven malignancy. Changes in pCa and, therefore, various Ca filtered loads were obtained by different degrees of bone resorption inhibition achieved with a single infusion of the bisphosphonate ibandronate, given at various doses on a randomized, double blind basis. PTHrP was determined at baseline in 147 of the patients and 7 days after bisphosphonate therapy in 73. Before ibandronate therapy, pCa was 3.36 +/- 0.02 mmol/L, mean TRCaI was increased at 3.09 +/- 0.03 mmol/L glomerular filtration rate (GFR; normal, 2.40-2.90), and 65% of patients had TRCaI above 2.90 mmol/L GFR. Mean serum PTHrP levels were 4.9 +/- 0.5 pmol/L (normal, <2.5) and values above the normal range were found in 53% of the patients (76% in lung and upper respiratory tract malignancies). By 7 days after the infusion of ibandronate, a decrease in pCa of 0.69 +/- 0.03 mmol/L (20.0 +/- 0.7%; P < 0.001) and in bone resorption [mean change in fasting urinary Ca, 0.09 +/- 0.04 mmol/L GFR (47.6 +/- 8.6%; P < 0.001) and 14.4 +/- 1.7 nmol/mmol (27.6 +/- 10.6%; P < 0.01) in deoxypyridinoline] was observed. TRCaI was slightly lowered by 0.30 +/- 0.09 mmol/L GFR. Mean changes in PTHrP, 1,25-dihydroxyvitamin D3, and PTH were +0.7 +/- 0.4 (P = NS), +27.6 +/- 3.0 (P < 0.001), and +2.9 +/- 0.8 (P < 0.005) pmol/L, respectively. After ibandronate treatment, the relative risk of relapsing hypercalcemia was particularly increased (3.43-fold) in lung and upper respiratory tract malignancies. These results obtained in a large cohort of patients indicate a significant prevalence of an increased renal tubular reabsorption of calcium index in hypercalcemia of malignancy and a substantial proportion of patients with detectable PTHrP.

Glucocorticoids decrease the production of parathyroid hormone-related protein in vitro but not in vivo in the Walker carcinosarcoma 256 rat model.

In 50-90% of cases, humoral hypercalcemia of malignancy (HHM) is due to tumor secretion of parathyroid hormone-related protein (PTHrP). Glucocorticoids are sometimes used as calcium lowering agents and there are in vitro results showing that glucocorticoids diminish PTHrP production. In this study we tested whether the serum-calcium-lowering effect of glucocorticoids is due to decreased PTHrP production by the tumor. As an animal and cell culture model we used the Walker carcinosarcoma (WCS) 256, a rat mammary carcinoma cell line producing PTHrP. In vitro, dexamethasone caused a dose-dependent inhibition of PTHrP production, whereby already 1-5 nmol/L revealed a significant decrease by WCS 256 cells. In contrast to these in vitro results, in WCS 256 tumor-bearing rats, dexamethasone (4 mg/kg body weight on day 4, and 1 mg/kg body weight from day 5 until day 7 after WCS transplantation; circulating dexamethasone levels > 20 nmol/L) did not decrease PTHrP production, PTHrP secretion, serum calcium, or tumor weight in vivo. We conclude that, in this PTHrP-mediated model of humoral hypercalcemia of malignancy, glucocorticoids do not decrease PTHrP production and secretion in vivo and do not show a calcium-lowering effect.

Interleukin-6 and tumor necrosis factor alpha levels after bisphosphonates treatment in vitro and in patients with malignancy.

Bisphosphonates are potent inhibitors of bone resorption and are widely used in the treatment of bone diseases. One of the side effects of administered aminobisphosphonates is transient fever and some biological changes that are suggestive of an acute phase response. Pamidronate [(3-amino-1-hydroxypropylidene).1, 1-bisphosphonate] and ibandronate [1-hydroxy-3-(methylpentylamino) propylidenebisphosphonate] incubated in heparinized whole blood at doses of 10(-4) and 10(-5) mol/L, induced the production of tumor necrosis factor alpha (TNFalpha). Moreover, pamidronate was found to slightly stimulate interleukin-6 IL-6 production. In contrast, clodronate (dichloromethylenebisphosphonate) did not increase IL-6 or TNFalpha. To investigate these phenomena in vivo, acute phase reaction was assessed in patients with malignant disease treated with 60 mg of pamidronate (n = 29), 1500 mg of clodronate (n = 8), or 0.5-2 mg of ibandronate (n = 6), all given intravenously. A significant decrease in lymphocyte and leukocyte count was observed in the pamidronate group. In the same group, seven patients (24%) showed a transient increase of body temperature above 37 degrees C with an increase > or = 0.5 degrees C at 24 h. These changes were not found in the patients treated with clodronate or ibandronate. Plasma IL-6 and TNFalpha levels increased significantly after pamidronate treatment, whereas no change was seen after clodronate infusion. The peak of IL-6 level (53.7 +/- 14.1 [SEM] pg/mL) was observed at 24 h, and that of TNFalpha level (26.9 +/- 3.4 pg/mL) at 48 h after the beginning of pamidronate administration (values before treatment, respectively: 28.6 +/- 7.1 pg/mL, p < 0.006; and 13.1 +/- 1.5 pg/mL, p = 0.0001). The peak of C-reactive protein (CRP) level was found at 48 h (41.0 +/- 7.8 vs. 25.5 +/- 5.6 mg/L before treatment, p < 0.01) and CRP levels were strongly correlated with IL-6 levels (p = 0.65,p < 0.001). Only one patient treated with ibandronate showed an increase in IL-6 and CRP levels. Patients treated with pamidronate, whose body temperatures were increased at 24 h, had a greater increases of circulating IL-6, TNFalpha, and CRP at 24 h and 48 h than patients without temperature increase. These results suggest that pamidronate treatment, but not clodronate and possibly not ibandronate at the doses used, induced an increase in the plasma levels of IL-6 and TNFalpha, which may be responsible for the acute phase reaction observed clinically.

Biochemical modulation of 5-fluorouracil by leucovorin with or without interferon-alpha-2c in patients with advanced colorectal cancer: final results of a randomised phase III study.

5-Fluorouracil (5-FU) remains the mainstay of treatment for advanced colorectal carcinoma, although response rates are generally less than 20%. Improved therapeutic efficacy has been reported using biochemical modulation of 5-FU by leucovorin (LV) or interferon alpha (IFN), the combination of 5-FU/LV frequently considered as standard therapy in metastatic colorectal cancer. In an attempt to enhance the cytotoxicity of 5-FU, a prospective randomised trial was initiated to compare 5-FU/LV with 5-FU/LV plus IFN. Patients were randomised to receive either LV, 100 mg/m2 intravenously (i.v.), followed by 5-FU, 500 mg/m2 as a 1-h i.v. infusion, daily for 4 days, followed by weekly infusions until week 8, or the same regimen of 5-FU/LV plus IFN-alpha-2c, 30 micrograms subcutaneously (s.c.), three times weekly. Cycles were repeated after a 2-week rest period. Among 269 enrolled patients, 219 were available for response and 243 for toxicity. An objective tumour response was observed in 38 of 107 (36%) and 28 of 112 (25%) patients in the treatment arms with and without IFN, respectively (difference not significant). There was no significant difference between the two groups in response duration (median 8.4 versus 12.1 months), time to treatment failure (median 6.5 versus 4.9 months), or overall survival (median 10.0 versus 12.6 months). However, patients in the IFN arm experienced significantly more haematological and gastrointestinal toxicity and more frequent alopecia. In conclusion, the addition of IFN to 5-FU/LV in the schedules and doses used in the study did not provide any clinical benefit over 5-FU/LV alone and cannot be recommended for routine use in the treatment of advanced colorectal cancer.

Effect of clodronate treatment on bone scintigraphy in metastatic breast cancer.

Because of their high affinity for bone, bisphosphonates are used both in the treatment of benign and malignant bone disease and in radiopharmaceutical bone imaging. A prospective study was undertaken to evaluate whether intravenous clodronate (dichloromethylene bisphosphonate) therapy might affect the results of bone scintigraphy with 99mTc-labeled methylene diphosphonate (MDP). In 11 female patients with breast cancer and metastatic bone disease, quantitative bone scans were obtained using a region of interest (ROI) method on Days 0 and 22. After intravenous clodronate therapy from Day 1 to Day 21, all metastatic bone lesions were still detectable, and median ROI ratios did not differ to a statistically significant extent from baseline values. Serum calcium levels decreased (p = 0.0449), whereas parathyroid hormone concentrations showed an increase (p = 0.0053). Mean serum levels of creatinine, inorganic phosphorus, osteocalcin, gamma glutaminyl-transpeptidase and alkaline phosphatase remained unchanged. However, a more than twofold rise in the serum activity of alkaline phosphatase was measured in three patients. We conclude that 3 wk of intravenous clodronate treatment did not impair the sensitivity of 99mTc-MDP bone scintigraphy in detecting bone lesions in patients with metastatic breast cancer.

Comparative tolerability of drug therapies for hypercalcaemia of malignancy.

The bisphosphonates are the treatment of choice in hypercalcaemia of malignancy. However, plicamycin (mithramycin) an calcitonin treatment may still be of value should bisphophonate treatment fail, and gallium nitrate has recently been introduced as an alternative therapy. We analysed the tolerability of different treatments based on articles identified in a Medline search covering the period 1979 through September 1998. Articles were included if they met two criteria: (i) quantitative assessment of adverse effects; (ii) inclusion of > or = 10 patients. Although bisphosphonates are generally well tolerated, elevation of serum creatinine level, nausea/vomiting and fever have been reported following their application. Patients receiving etidronate (n = 268) or clodronate (n = 127) more frequently experienced creatinine elevation (8 and 5%, respectively) than did patients receiving pamidronate (n = 424; 2%), aledronate (n = 79; 0%), or ibandronate (n = 203; <1%). The difference in the frequency of reported creatinine level elevations reached statistical significance only for etidronate (z-test: p < 0.001 versus pamidronate; p < 0.02 versus alendronate; p < 0.001 versus ibandronate). With regard to the frequency of creatinine level elevations, clodronate treatment did not differ significantly from treatment with pamidronate, alendronate and ibandronate. An exception among the bisphosphonates is tiludronate, which has been reported on s a treatment of hypercalcaemia in only 1 study (n = 19) resulting in 1 case of lethal and 1 case of manageable acute renal failure. Nausea and vomiting are rare adverse effects of bisphosphonate treatment but seem to be more frequent with first generation drugs: etidronate (8%) and clodronate (7%) versus pamidronate (2%) [p < 0.001 and 0.009, respectively] and versus ibandronate (<1%) [p< 0.002 and 0.02, respectively]. Bisphosphonates containing a nitrogen atom were associated with an acute phase reaction leading to reported fever in 16% of pamidronate, 20% of aledronate, and 11% of ibandronate-treated patients. The most frequently reported adverse effects of treatment with the cytostatic drug plicamycin were hepatotoxicity (26%), nausea/vomiting (23%), and serum creatinine level elevation (5%). Furthermore. plicamycin application was associated with bone marrow suppression and a bleeding tendency due to abnormalities in multiple clotting factors and platelet dysfunction. The use of calcitonin is limited more by the short duration of its therapeutic effect than by toxicities (most frequent: nausea/vomiting in 16% of treated cases). The few publications on gallium nitrate in the treatment of hypercalcaemia of malignancy characterise it as an efficient drug, which is, however, associated with a higher frequency of renal toxicity (10%) and of nausea and vomiting (14%) than are the bisphosphonates.

pS2 protein status fails to be an independent prognostic factor in an average breast cancer population.

In this study we analysed the cytosolic concentrations of the estrogen-regulated protein pS2 in tumors of 462 breast cancer patients, 16 benign breast tumors and 58 metastases. The median pS2 values were highest in breast cancer, followed by benign tumors and metastases (Kruskal-Wallis Test: p < 0.05). Information on other prognostic factors and clinical outcome was available for 354 patients (median follow-up, 35 months). We found a pS2 value of 2 ng/mg protein to be the best cut-off level to discriminate between pS2+ (63%) and pS2- (37%) tumors with respect to relapse-free survival (RFS) and overall survival (OS). The pS2 status was significantly correlated with age, estrogen receptor (ER) and progesterone receptor (PR) status. pS2 was negatively correlated with grading and was more often positive in invasive lobular than in invasive ductal carcinomas. ER, pS2 and grading were highly significantly correlated with each other. In univariate analysis pS2- patients showed a significantly shorter RFS (p = 0.0001) and OS (p = 0.0005). However, multiple regression analysis revealed that in our series of patients the pS2 status provides no independent prognostic information.

[PTH-related protein (PTHrP) in serum of patients with tumor hypercalcemia]. / PTH-related protein (PTHrP) im Serum von Patienten mit Tumorhyperkalzämie.

Parathyroid hormone-related protein (PTHrP) is a recently described hormone, that was isolated from malignant tumors. It shows many properties of parathyroid hormone (PTH) and is related to the pathogenesis of humoral hypercalcemia of malignancy. Therefore, we analyzed PTHrP in the sera of 30 patients with hypercalcemia of malignancy and compared the values with those obtained in patients with primary hyperparathyroidism, Paget's disease of bone, and normal subjects. PTHrP was quantitated with radioimmunoassay (RIA) using aminoterminal antibodies without and with chromatographical sample purification applying SEP-PAK C18 cartridges. Measurements of PTHrP without sample purification yielded high values in all patient groups. There was no differentiation between patient groups. However, quantitation of PTHrP after SEP-PAK C18 purification of the samples resulted in values above the normal range only in tumour patients. In 30 normal subjects PTHrP levels were 110 +/- 75 pg-eq/ml. Eight out of 30 patients with malignant tumours displayed PTHrP-concentrations above 335 pg-eq/ml. PTHrP levels in patients with primary hyperparathyroidism or Paget's disease of bone were within the normal range. PTHrP concentrations were not affected from renal function. We conclude, that determination of PTHrP after sample purification may contribute to the differential diagnosis of malignant disease.