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.

Rapid administration of ibandronate does not affect renal functioning: evidence from clinical studies in metastatic bone disease and hypercalcaemia of malignancy.

Ibandronate is a third-generation aminobisphosphonate that has an excellent safety record in hypercalcaemia of malignancy, and has recently been approved for the prevention of skeletal events from metastatic breast cancer. This paper reviews the safety data from clinical studies of intravenous ibandronate by infusion or injection, focusing on renal adverse events (AEs). In clinical trials of patients with hypercalcaemia of malignancy, 2-h infusions of ibandronate at doses of up to 6 mg had a low potential for renal events. In a phase III trial of patients with metastatic bone disease from breast cancer, 6 mg ibandronate infused over 1-2 h had a renal safety profile comparable to that of placebo. In pilot studies, repeated daily infusions of ibandronate (4 mg infused over 2 h for four consecutive days, or 6 mg infused over 1 h for three consecutive days) for severe metastatic bone pain were not associated with any renal AEs. The safety of single 15-min infusions of 6 mg ibandronate has been demonstrated in healthy volunteers and patients with metastatic bone disease from breast cancer or multiple myeloma. Furthermore, single and rapid bolus injections of 2 or 3 mg ibandronate did not increase the risk of renal dysfunction in patients with skeletal metastases. Implications for the renal safety of ibandronate in the management of patients with metastatic bone disease are discussed.

Oral ibandronate reduces the risk of skeletal complications in breast cancer patients with metastatic bone disease: results from two randomised, placebo-controlled phase III studies.

Although intravenous (i.v.) bisphosphonates are the standard of care for metastatic bone disease, they are less than ideal for many patients due to infusion-related adverse events (AEs), an increased risk of renal toxicity and the inconvenience of regular hospital visits. The use of oral bisphosphonate therapy is limited by concerns over efficacy and gastrointestinal (GI) side effects. There remains a clinical need for an oral bisphosphonate that offers equivalent efficacy to i.v. bisphosphonates, good tolerability and dosing convenience. Oral ibandronate, a highly potent, third-generation aminobisphosphonate, has been evaluated in phase III clinical trials of patients with bone metastases from breast cancer. In two pooled phase III studies, patients with breast cancer and bone metastases were randomised to receive oral ibandronate 50 mg (n=287) or placebo (n=277) once daily for up to 96 weeks. The primary end point was the skeletal morbidity period rate (SMPR), defined as the number of 12-week periods with new skeletal complications. Multivariate Poisson's regression analysis was used to assess the relative risk of skeletal-related events in each treatment group during the study period. Oral ibandronate 50 mg significantly reduced the mean SMPR compared with placebo (0.95 vs 1.18, P=0.004). There was a significant reduction in the mean number of events requiring radiotherapy (0.73 vs 0.98, P<0.001) and events requiring surgery (0.47 vs 0.53, P=0.037). Poisson's regression analysis confirmed that oral ibandronate significantly reduced the risk of a skeletal event compared with placebo (hazard ratio 0.62, 95% CI=0.48, 0.79; P=0.0001). The incidence of mild treatment-related upper GI AEs was slightly higher in the oral ibandronate 50 mg group compared with placebo, but very few serious drug-related AEs were reported. Oral ibandronate 50 mg is an effective, well-tolerated and convenient treatment for the prevention of skeletal complications of metastatic bone disease.

Efficacy and safety of ibandronate in the treatment of hypercalcemia of malignancy: a randomized multicentric comparison to pamidronate.

GOALS: To compare the efficacy and safety of ibandronate and pamidronate in patients with hypercalcemia of malignancy (HCM). PATIENTS AND METHODS: Seventy-two patients with HCM [albumin-corrected serum calcium (CSC) >2.7 mmol/l] were treated with a single infusion of ibandronate (2 or 4 mg) or pamidronate (15, 30, 60, or 90 mg) on day 0. The dose was dependent on the severity of hypercalcemia (baseline CSC level). CSC was assessed daily until day 4, then at intervals until day 28. The primary endpoint was lowering of CSC at day 4. Secondary endpoints included the number of patients responding and time to re-increase following response. MAIN RESULTS: Using the CSC baseline approach, the most frequently administered doses were 4 mg ibandronate (78.4%) and 60 mg pamidronate (50.0%). Mean lowering of CSC at day 4 was 0.6 mmol/l for ibandronate and 0.41 mmol/l for pamidronate. The 95% confidence interval for the difference ibandronate pamidronate had a lower limit of 0.05 mmol/l, indicating that ibandronate was as effective as pamidronate. The number of patients responding to the two agents was also similar; 76.5% of ibandronate patients and 75.8% of pamidronate patients were rated as responders after the first dose of study medication. The median time to re-increase after response was longer for ibandronate (14 days) than pamidronate (4 days) ( P=0.0303). In the subgroup of 17 patients with high baseline CSC (>3.5 mmol/l), ibandronate appeared to be more effective than pamidronate. The safety profile of both agents was similar. CONCLUSIONS: Ibandronate is at least as effective as pamidronate in the treatment of HCM. Furthermore, in patients with higher baseline CSC ibandronate appears to be more effective than pamidronate. The duration of response is significantly longer with ibandronate than pamidronate.

Regional cerebral blood flow in patients suffering from post-traumatic stress disorder.

OBJECTIVE: The aim of the study was to determine whether regional cerebral blood flow in survivors of torture suffering from post-traumatic stress disorder (PTSD) differed significantly from that in healthy controls. METHOD: We examined the cerebral regional distribution of 99m-technetium-hexamethylpropyleneamineoxime (HMPAO) using single photon emission computed tomography (SPECT) in 8 patients and in 8 healthy controls. A semi-quantitative analysis was performed in which symmetrical regions of interest (ROI) were drawn in all subjects. RESULTS: Regional blood flow was markedly more heterogeneous in patients suffering from PTSD than in healthy controls. The differences are significant. CONCLUSION: Severe psychological trauma induced by torture can cause neurobiologic alterations that may contribute, even years after the original trauma, to a number of complaints commonly expressed by patients suffering from PTSD.

Biochemical markers of bone formation in patients with plasma cell dyscrasias and benign osteoporosis.

BACKGROUND: Myeloma-induced bone loss is related to an uncoupling of bone formation and bone resorption. The aim of the present study was to assess the potential clinical value of biochemical markers of bone formation in the work up of patients with plasma cell dyscrasias. METHODS: Serum total alkaline phosphatase, bone-specific alkaline phosphatase (BAP), and osteocalcin (OC) were measured in 43 patients with newly diagnosed multiple myeloma (MM), in 40 patients with monoclonal gammopathy of undetermined significance (MGUS), in 40 patients with untreated benign vertebral osteoporosis (OPO), and in 48 healthy adults. RESULTS: In MM and MGUS patients, serum BAP, but not serum OC, was lower than in healthy controls (P<0.05). Serum OC was higher in patients with OPO than in healthy controls (P<0.05). The strongest associations between markers were found in OPO patients and in healthy adults. MM patients with early-stage disease or without detectable osteolysis had decreased serum BAP values (P<0.05). Serum OC was higher in MM patients with stage III disease (P<0.05) than in healthy controls. MM patients with OPO-like bone involvement had lower BAP values than sex- and age-matched MGUS patients with OPO-like bone involvement and patients with benign OPO (P<0.05). CONCLUSIONS: In patients with plasma cell dyscrasias, serum BAP, rather than serum OC, appears to reflect a suppressed bone formation rate and may be helpful in the differentiation between benign and myeloma-induced OPO. However, the overall clinical use of biochemical markers of bone formation in patients with plasma cell dyscrasia appears limited.

Serum bone sialoprotein as a marker of tumour burden and neoplastic bone involvement and as a prognostic factor in multiple myeloma.

To test the potential of immunoreactive BSP, a non-collagenous bone matrix component, as a clinical guide in patients with plasma cell dyscrasias, serum BSP concentrations were measured in 62 patients with newly diagnosed multiple myeloma (MM) followed over a period of 4 years, in 46 patients with monoclonal gammopathy of undetermined significance (MGUS), in 71 patients with untreated benign vertebral osteoporosis (OPO), and in 139 healthy adults. Results were compared with clinical and laboratory data, including serum osteocalcin (OC), and urinary pyridinoline (PYD) and deoxypyridinoline (DPD) as markers of bone turnover. In MM, serum BSP, and urinary PYD and DPD were higher than in healthy controls and in MGUS or OPO (P< 0.001). BSP levels correlated with the bone marrow plasma cell content (r = 0.40, P< 0.001), and serum beta2-microglobulin (r = 0.31, P < 0.01). The differentiation of MM from healthy controls and from MGUS or OPO was highest for BSP. After chemotherapy, BSP reflected the response to treatment and correlated with the change in monoclonal protein (r = 0.55, P< 0.001). MM patients with normal baseline BSP levels survived longer than patients with initially elevated BSP values (P< 0.001, log rank test). Only serum monoclonal protein and BSP were independent predictors of survival. We conclude that in MM, BSP levels are associated with skeletal involvement and tumour cell burden. The quantification of serum BSP may be a non-invasive method for the diagnosis and follow-up, and may improve the prognostic value of conventional staging in MM.

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.

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.

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.

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.

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.

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.

Bone resorption in multiple myeloma and in monoclonal gammopathy of undetermined significance: quantification by urinary pyridinium cross-links of collagen.

To quantify osseous breakdown in multiple myeloma (MM), monoclonal gammopathy of undetermined significance (MGUS), and benign osteoporosis, we measured urinary levels of pyridinium cross-links of collagen in 50 patients with newly diagnosed and untreated MM, 40 patients with MGUS, 40 untreated patients with osteoporotic vertebral fractures, and 64 healthy adults. Ion-paired, reverse-phase high-performance liquid chromatography (HPLC) was used to measure total urinary excretion of pyridinoline (h-PYD) and deoxypyridinoline (h-DPD). Urinary excretion of free immunoreactive deoxypyridinoline (i-DPD) was determined with an enzyme immunoassay. MM patients had significantly (P < .0001) higher levels of h-PYD, h-DPD, and i-DPD than the healthy adults, patients with MGUS, or patients with osteoporosis. The MGUS and osteoporosis groups presented with elevated (P < .05) levels of urinary pyridinium cross-links when compared with healthy controls. In 20 MM patients who subsequently received chemotherapy, the percent changes in i-DPD did not correlate with the changes in the monoclonal protein. In one of three patients experiencing a transition of initial MGUS into stage I MM, i-DPD increased above the upper limit of the normal range. In 13 patients with stable MGUS, i-DPD remained normal in repeated measurements. Based on the upper limits of the normal range, the sensitivity of urinary pyridinium cross-links in stage I and II MM was low (<50%), but it was between 78% (h-DPD) and 93% (i-DPD) in stage III MM. Specificity in patients with MGUS was between 87% (h-PYD) and 97% (h-DPD). In conclusion, determining the urinary excretion of pyridinium cross-links seems to be a promising noninvasive and thus easily repeatable method for evaluating the actual degree of osseous breakdown. Although measurement of pyridinium cross-link levels is not useful in discriminating patients with MGUS from early-stage myeloma patients, determination of i-DPD levels may contribute importantly to clinical guidance, since increased i-DPD levels seem to identify patients who are particularly likely to benefit from osteoclast-inhibiting drugs such as bisphosphonates. The fact that in a number of patients paraprotein concentrations and i-DPD levels did not change in parallel but instead diverged strongly after chemotherapy might explain the observation that bone lesions sometimes progress even in patients who achieve complete remission.

Interphase fluorescence in situ hybridization improves the detection of malignant cells in effusions from breast cancer patients.

In diagnostic evaluation of effusions, difficulties are encountered when atypical reactive mesothelial cells have to be differentiated from malignant cells. We tested the impact of fluorescence in situ hybridization (FISH) to identify metastatic cells in breast cancer effusions by detection of numerical chromosomal changes. Pleural and ascitic fluid samples (n=57) from 41 breast cancer patients were concomitantly evaluated by routine cytology and FISH, using centromere-specific probes representing chromosomes 7, 11, 12, 17 and 18. After setting stringent cut-off levels deduced from non-malignant control effusions (n=9), the rates of cells with true aneuploidy were determined in each effusion sample from breast cancer patients. The occurrence of aneuploid cells, as detected by FISH and indicative of malignancy, was correlated with the cytological findings. Routine cytology revealed malignancy in 60% of effusions. Using FISH, aneuploid cell populations could be observed in 94% of cytologically positive and in 48% of cytologically negative effusions, thus reverting diagnosis to malignancy. To confirm malignancy in cases with a low frequency of aneuploid cells, two-colour FISH was additionally performed and indeed showed heterogeneous chromosomal aneuploidy within single nuclei. We conclude that FISH is a valuable tool in the diagnosis of malignancy and may serve as an adjunct to routine cytological examination, as demonstrated here for breast cancer effusions.

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.

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.

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.