Use of radionuclides for the palliation of bone metastases

Analyses of production capacity of 89Sr and 90Sr in the 2 MW molten salt reactor

The production capacity of ⁸⁹Sr and ⁹⁰Sr in the 2 MW MSR are evaluated. The gaseous ⁸⁹Kr and ⁹⁰Kr are extracted from the core through the helium bubbling system, and then decay to ⁸⁹Sr and ⁹⁰Sr, respectively. In order to improve purity of ⁸⁹Sr product, two cooling devices are adopted in the ⁸⁹Sr and ⁹⁰Sr production system. The annual yields of ⁸⁹Sr and ⁹⁰Sr are about 9000 Ci and 32 Ci, respectively, and the impurity of ⁸⁹Sr product is less than 2 ppm which can meet the medical requirement.

Internal dosimetry studies of 170Tm-EDTMP complex, as a bone pain palliation agent, in human tissues based on animal data

Radiopharmaceuticals with therapeutic applications are designed to deliver high doses of radiation to target organs with minimizing unwanted radiation to healthy tissues. Owing to the potential of targeted radiotherapy to treat a wide range of malignancies, ¹⁷⁰Tm -EDTMP was developed for possible therapeutic applications. This study describes absorbed dose prediction of ¹⁷⁰Tm-EDTMP in human organs after animal injection which is determined via medical internal radiation dose (MIRD) and MCNP-4C code methods. It was estimated that a 1-MBq administration of ¹⁷⁰Tm-EDTMP into the human body would result in an absorbed dose of 37.9 mGy (MIRD method) and 38.02 mGy (MCNP-4C code) in the bone surface after 60 days post injection. Highest and lowest difference between MIRD and MCNP results are for lung and bone surface respectively. Finally, the results show that there is a good agreement between MIRD method and MCNP-4C simulation code for absorbed dose estimation.

Targeted Palliative Radionuclide Therapy for Metastatic Bone Pain

Bone metastasis develops in multiple malignancies with a wide range of incidence. The presence of multiple bone metastases, leading to a multitude of complications and poorer prognosis. The corresponding refractory bone pain is still a challenging issue managed through multidisciplinary approaches to enhance the quality of life. Radiopharmaceuticals are mainly used in the latest courses of the disease. Bone-pain palliation with easy-to-administer radionuclides offers advantages, including simultaneous treatment of multiple metastatic foci, the repeatability and also the combination with other therapies. Several β¯- and α-emitters as well as pharmaceuticals, from the very first [⁸⁹Sr]strontium-dichloride to recently introduced [²²³Ra]radium-dichloride, are investigated to identify an optimum agent. In addition, the combination of bone-seeking radiopharmaceuticals with chemotherapy or radiotherapy has been employed to enhance the outcome. Radiopharmaceuticals demonstrate an acceptable response rate in pain relief. Nevertheless, survival benefits have been documented in only a limited number of studies. In this review, we provide an overview of bone-seeking radiopharmaceuticals used for bone-pain palliation, their effectiveness and toxicity, as well as the results of the combination with other therapies. Bone-pain palliation with radiopharmaceuticals has been employed for eight decades. However, there are still new aspects yet to be established.

Novel Agents and Targets in Managing Patients with Metastatic Prostate Cancer

Background

Docetaxel has recently been found to improve survival in patients with metastatic androgen-independent prostate cancer (AIPC). Chemotherapy as a first-line option leaves room for improvement, while second-line options are multiple and somewhat controversial.

Methods

Clinically relevant articles focusing on chemotherapy drugs for metastatic prostate cancer and their mechanism of action and efficacy were reviewed from January 2004 through April 2006.

Results

Docetaxel is the standard of care for AIPC. However, for doublets with docetaxel or second-line chemotherapy, multiple studies have shown interesting and promising results with calcitriol, thalidomide, bevacizumab, satraplatin, vaccines, ixabepilone, and atrasentan.

Conclusions

Docetaxel should be considered for first-line treatment of metastatic AIPC. Due to its progression-free survival of only 6 months, more effective drugs and drug combinations need to be developed to treat patients with AIPC. Combination treatments with docetaxel and other new agents are promising, but adequately powered phase III trials need to be conducted with survival as the principal endpoint for these promising drug combinations.

Comparative Therapeutic Efficacy of 153Sm-EDTMP and 177Lu-EDTMP for Bone Pain Palliation in Patients with Skeletal Metastases: Patients' Pain Score Analysis and Personalized Dosimetry

Introduction

The aim of the present study was to compare the therapeutic efficacy of ¹⁵³Sm-EDTMP and ¹⁷⁷Lu-EDTMP in pain palliation in cancer patients with skeletal metastases.

Materials and methods

Thirty patients (25 M:5 F, mean age: 66.0 ± 14.7 years) of breast/prostate cancer with documented skeletal metastases were recruited prospectively. Twenty patients were considered randomly for treatment with ¹⁵³Sm-EDTMP and with ¹⁷⁷Lu-EDTMP in 10 patients, respectively. Using fixed dose of 37.0 MBq/kg body weight of each, the mean administered doses of ¹⁵³Sm-EDTMP and ¹⁷⁷Lu-EDTMP were 2,155.2 ± 419.6 MBq (1,347–2,857) and 1,935.1 ± 559.4 MBq (1,073–2,627), respectively. Anterior and posterior whole body images were acquired at different time points following radioactivity administration. The first data set of pre-void images (acquired at 0.5 h) representing the total activity of either of ¹⁵³Sm-EDTMP or ¹⁷⁷Lu-EDTMP was considered as reference images. All the serial images were used for patients’ dosimetry analysis by using organ level internal dosimetry assessment algorithm. Reduction in pain scoring was assessed clinically over 8 weeks by using appropriate WHO criteria and correlated with the absorbed dose to the metastatic sites.

Results

A total of 86 metastatic lesions clearly visualized on post-therapy serial images (matching on bone scans) were evaluated for absorbed dose calculations. Both ¹⁵³Sm-EDTMP and ¹⁷⁷Lu-EDTMP delivered similar absorbed dose to the metastatic sites, i.e., 6.22 ± 4.21 and 6.92 ± 3.92 mSv/MBq, respectively. The mean absorbed doses to various other organs were found to be comparable and within the safe limits. A complete response (CR) for each radionuclide was evaluated as 80.0%. No significant alternation in blood parameters and no untoward reaction were observed. However, a mild to severe toxicity was observed in two patients (1 each with ¹⁵³Sm-EDTMP and ¹⁷⁷Lu-EDTMP). Kaplan–Meier survival analysis demonstrated that 27/30 patients had pain-free survival (CR) up to the observational period of 8 weeks. However, no statistically significant correlation could be established between the pain scoring and absorbed dose to metastatic sites.

Conclusion

Both the radionuclides thus offer an effective and comparable therapeutic efficacy for bone pain palliation at an affordable cost and can be used interchangeably as per the availability.

Radiopharmaceuticals for the palliation of painful bone metastases

Metastatic bone pain is prevalent in advanced cancer, and, despite a plethora of available therapies, effective palliation remains a clinical challenge. Bone-seeking radiopharmaceuticals are an often-overlooked but valuable analgesic option for select patients. These agents work by binding to hydroxyapatite at the tumor-bone interface of osteoblastic lesions, delivering therapeutic doses of radiation to closely circumscribed tissue regions. They have been shown to reduce pain and improve quality of life. Their safety, simplicity, convenience of administration, and cost-effectiveness make them suitable for hospice and palliative care settings.

Internal radiation therapy: a neglected aspect of nuclear medicine in the molecular era

With increasing evidence, internal radiation therapy, also known as brachytherapy, has become a neglected aspect of nuclear medicine in the molecular era. In this paper, recent developments regarding internal radiation therapy, including developments in radioiodine-131 (¹³¹I) and thyroid, radioimmunotherapy (RIT) for non-Hodgkin lymphoma (NHL), and radiopharmaceuticals for bone metastases. Relevant differences and status of their applications in China were mentioned as well. These molecular mediated internal radiation therapies are gaining increasing importance by providing palliative and curative treatments for an increasing number of diseases and becoming one of the important parts of molecular nuclear medicine.

Clinical Efficacy and Safety Comparison of 177Lu-EDTMP with 153Sm-EDTMP on an Equidose Basis in Patients with Painful Skeletal Metastases

This prospective study compared 177Lu-ethylene diamine tetramethylene phosphonate (EDTMP) with 153Sm-EDTMP for painful skeletal metastases.

METHODS

Half of the 32 patients were treated with 177Lu-EDTMP and half with 153Sm-EDTMP, at 37 MBq/kg of body weight. Analgesic, pain, and quality-of-life scores (EORTC, Karnofsky, ECOG) and bone proliferation marker were used to examine efficacy. Hematologic toxicity was evaluated using NCI-CTCAE and compared between groups at baseline and each month till 3 mo after therapy. Pain relief was categorized as complete, partial, minimal, or none.

RESULTS

Pain relief with 177Lu-EDTMP was 80%: 50% complete, 41.67% partial, and 8.33% minimal. Pain relief with 153Sm-EDTMP was 75%: 33.33% complete, 58.33% partial, and 8.33% minimal. The difference was not significant (P=1.000). Quality of life at 3 mo after therapy improved significantly in both groups as per ECOG score (P=0.014 and 0.005 for 177Lu-EDTMP and 153Sm-EDTMP, respectively), Karnofsky index (P=0.007 and 0.023 for 177Lu-EDTMP and 153Sm-EDTMP, respectively), and EORTC score (P=0.004 and <0.001 for 177Lu-EDTMP and 153Sm-EDTMP, respectively). Bone proliferation marker in responders of both groups dropped significantly (P=0.008 for 177Lu-EDTMP and P=0.019 for 153Sm-EDTMP), parallel to clinical response. For 177Lu-EDTMP, anemia, leukopenia, and thrombocytopenia were nonserious (grade I/II) in 46.67%, 46.67%, and 20%, respectively, and serious (grade III/IV) in 20%, 6.67%, and 0%, respectively. For 153Sm-EDTMP, anemia, leukopenia, and thrombocytopenia were nonserious (grade I/II) in 62.5%, 31.25%, and 18.75%, respectively, and serious (grade III/IV) in 18.75%, 0%, and 6.25%, respectively. One patient treated with 153Sm-EDTMP had grade IV thrombocytopenia but required no blood transfusion. Differences between groups were not significant for either nonserious or serious toxicity. For 177Lu-EDTMP, 3 of 12 responders experienced the flare phenomenon on the third day after therapy and one on the fifth day, showing no response to therapy. For 153Sm-EDTMP, 2 of 12 responders experienced the flare phenomenon, both on the third day after therapy.

CONCLUSION

177Lu-EDTMP has pain response efficacy similar to that of 153Sm-EDTMP and is a feasible and safe alternative, especially in centers with no nearby access to 153Sm-EDTMP.

Dosimetry of bone metastases in targeted radionuclide therapy with alpha-emitting (223)Ra-dichloride

PURPOSE

Ra-dichloride is an alpha-emitting radiopharmaceutical used in the treatment of bone metastases from castration-resistant prostate cancer. Image-based dosimetric studies remain challenging because the emitted photons are few. The aim of this study was to implement a methodology for in-vivo quantitative planar imaging, and to assess the absorbed dose to lesions using the MIRD approach.

METHODS

The study included nine Caucasian patients with 24 lesions (6 humeral head lesions, 4 iliac wing lesions, 2 scapular lesions, 5 trochanter lesions, 3 vertebral lesions, 3 glenoid lesions, 1 coxofemoral lesion). The treatment consisted of six injections (one every 4 weeks) of 50 kBq per kg body weight. Gamma-camera calibrations for (223)Ra included measurements of sensitivity and transmission curves. Patients were statically imaged for 30 min, using an MEGP collimator, double-peak acquisition, and filtering to improve the image quality. Lesions were delineated on (99m)Tc-MDP whole-body images, and the ROIs superimposed on the (223)Ra images after image coregistration. The activity was quantified with background, attenuation, and scatter correction. Absorbed doses were assessed deriving the S values from the S factors for soft-tissue spheres of OLINDA/EXM, evaluating the lesion volumes by delineation on the CT images.

RESULTS

In 12 lesions with a wash-in phase the biokinetics were assumed to be biexponential, and to be monoexponential in the remainder. The optimal timing for serial acquisitions was between 1 and 5 h, between 18 and 24 h, between 48 and 60 h, and between 7 and 15 days. The error in cumulated activity neglecting the wash-in phase was between 2 % and 12 %. The mean effective half-life (T 1/2eff) of (223)Ra was 8.2 days (range 5.5-11.4 days). The absorbed dose (D) after the first injection was 0.7 Gy (range 0.2-1.9 Gy. Considering the relative biological effectiveness (RBE) of alpha particles (RBE = 5), D RBE = 899 mGy/MBq (range 340-2,450 mGy/MBq). The percent uptake of (99m)Tc and (223)Ra (activity extrapolated to t = 0) were significantly correlated.

CONCLUSION

The feasibility of in vivo quantitative imaging in (223)Ra therapy was confirmed. The lesion uptake of (223)Ra-dichloride was significantly correlated with that of (99m)Tc-MDP. The D RBE to lesions per unit administered activity was much higher than that of other bone-seeking radiopharmaceuticals, but considering a standard administration of 21 MBq (six injections of 50 kBq/kg to a 70-kg patient), the mean cumulative value of D RBE was about 19 Gy, and was therefore in the range of those of other radiopharmaceuticals. The macrodosimetry of bone metastases in treatments with (223)Ra-dichloride is feasible, but more work is needed to demonstrate its helpfulness in predicting clinical outcomes.

Metastatic Bone Pain Palliation using (177)Lu-Ethylenediaminetetramethylene Phosphonic Acid

¹⁷⁷Lu-ethylenediaminetetramethylene phosphonic acid (EDTMP) is presently suggested as an excellent bone seeking radionuclide for developing metastatic bone pain (MBP) palliation agent owing to its suitable nuclear decay characteristics. To find the exact dosage and its efficiency, this clinical study was performed on the human being, using ¹⁷⁷Lu-EDTMP for MBP palliation. ¹⁷⁷Lu-EDTMP was prepared by Iran, atomic energy organization. Thirty consecutive patients with determined tumors, incontrollable MBP, and positive bone scan at 4 weeks before the beginning of the study participated in this study in the nuclear medicine ward. ¹⁷⁷Lu-EDTMP in the form of sterile slow IV injection was administered with a dose of 29.6 MBq/kg. Short form of brief pain inventory questionnaire was used to evaluate the efficiency of the intervention. Questionnaires were filled out by an expert nuclear physician every 2 weeks while the cell blood count was also checked every 2 weeks up to 12 weeks for evaluation of bone marrow suppression and hematological toxicity. Furthermore, whole body scan was done at days 1, 3, and 7. Twenty-five patients showed a significant pain relief since 2 weeks after the injection, and continued until the end of the follow up period (12 weeks). There were no significant early complications such as bone marrow suppression, hematological toxicity, and no systemic adverse effects. No complication was observed in renal function. Twenty one patients showed flare phenomenon that was started after the 12.2 ± 1.78 h lasting for 38.4 ± 23.08. Sixteen patients (53%) were completely treated; nine patients (30%) showed a partial response, and five patients (17%) had no response to treatment. Total response to treatment was achieved in 25 patients (83%). At the end of the evaluation, no bone marrow suppression or hematologic toxicity was observed. ¹⁷⁷Lu-EDTMP has shown suitable physical and biological properties with good results in long term bone pain relief for patients with bone metastasis.

Palliative effects and adverse events of strontium-89 for prostate cancer patients with bone metastasis

The aim of the present study was to evaluate the palliative effects and adverse events of strontium-89 (Sr-89) in patients with bone metastasis from prostate cancer. A total of 18 patients with prostate cancer and painful bone metastases, as diagnosed on bone scintigraphy, who were treated with Sr-89 at the National Kyushu Cancer Center between February, 2008 and April, 2014 were reviewed. Of the 18 subjects, 13 (72.2%) achieved a pain response, whereas 5 were classified as pain non-responders (27.8%). According to a logistic regression analysis, the pre-administration characteristics, including age, prostate-specific antigen (PSA), alkaline phosphatase (ALP), history of bone-modifying agent administration, opioid use or palliative radiation therapy, time after the combined androgen blockade nadir and time since the pain onset, were not found to be significant predictors of the pain response. Similarly, the post-administration characteristics, including pain flares and the PSA and ALP response, were not found to be significant predictors of the pain response. Although no patients exhibited leukocyte toxicities, 2 patients experienced myelosuppression, involving anemia and thrombocytopenia, requiring transfusion of red cell or platelet concentrate following Sr-89 treatment. Of the 18 patients, 5 (27.8%) reported pain flares, all of whom were successfully treated with rescue drugs alone. According to the logistic regression analysis, of the pre-administration characteristics, only ALP was identified as a significant predictor of bone marrow suppression in the univariate and multivariate analyses (P=0.006). Therefore, Sr-89 treatment was found to be effective in ameliorating bone pain associated with metastasis from prostate cancer. Although it is difficult to identify the patients who will receive pain relief prior to Sr-89 administration, this drug should be administered during the early stages due to the potential for bone marrow suppression in patients with high ALP levels.

Samarium-153-ethylene diamine tetramethylene phosphonate, a beta-emitting bone-targeted radiopharmaceutical, useful for patients with osteoblastic bone metastases

Bone metastases are prevalent among cancer patients and frequently cause significant morbidity. Oncology providers must mitigate complications associated with bone metastases while limiting therapy-related adverse effects and their impact on quality of life. Multiple treatment modalities, including chemotherapy, surgery, external beam radiation therapy, and radioisotopes, among others, have been recommended and utilized for palliative treatment of bone metastases. Radioisotopes such as samarium-153 are commonly used in the setting of multifocal bone metastases due to their systemic distribution, affinity for osteoblastic lesions, acceptable toxicity profile, and convenience of administration. This review focuses on samarium-153, first defining its radiobiologic and pharmacokinetic properties before describing many clinical trials that support its use as a safe and effective tool in the palliation of patients with bone metastases.

Effective use of strontium-89 in osseous metastases

Bone is one of the organs to which cancer metastasizes most frequently. However, it is not a vital organ, therefore, survival after the occurrence of osseous metastasis is relatively favorable. Improvements of medical treatment bring prolonged survival to patients with osseous metastases. But this makes us to recognize the importance of quality of life (QOL) due to several factors, including pain. It is important for oncologists to know how to deal with such painful osseous metastases, as pain relief may enable patients to live their remaining lives to the fullest. Strontium-89 (89Sr) has been used worldwide as in Japan, while being reported to have positive effects on pain relief and QOL improvement in patients with osseous metastases. This review paper is aimed to present not only the history, roles, and medical characters of 89Sr, but also new aspects, such as how to use bone turnover markers, which location of osseous metastases is suitable for effective use of 89Sr.

Concurrent use of Sr-89 chloride with zoledronic acid is safe and effective for breast cancer patients with painful bone metastases

Our aim in this study was to examine the safety and efficacy of the concurrent use of the radiopharmaceutical strontium-89 (Sr-89) chloride with zoledronic acid in standard anticancer therapy for breast cancer patients with painful multifocal bone metastases. The study comprised 16 breast cancer patients with painful multifocal bone metastases detected by bone scintigraphy, computed tomography or magnetic resonance imaging. All patients were treated with Sr-89 and zoledronic acid concurrently between March 2007 and February 2011 as part of a standard therapeutic regimen comprising chemotherapy, endocrine therapy, molecular targeting therapy and targeted radiotherapy. Sr-89 was administered intravenously at 2 MBq/kg to a maximum of 141 MBq per person. Safety was evaluated according to myelotoxicity as measured by the Common Terminology Criteria for Adverse Events (v3.0). To assess treatment efficacy, we monitored changes in analgesic drug dosages. Furthermore, bremsstrahlung imaging after the administration of Sr-89 was utilized to examine the relationship between the accumulation of Sr-89 in metastatic sites and treatment efficacy. Based on the results, a total of 14 out of 16 patients (88%) reported bone pain relief, indicating a high efficacy of Sr-89 combined with zoledronic acid. In responsive cases, a strong uptake of Sr-89 was observed on bremsstrahlung imaging at the same sites indicated by (99m)Tc bone scintigraphy. Moreover, severe myelosuppression (> grade 3) was not observed, and adverse events were tolerable. In conclusion, the use of Sr-89 with zoledronic acid in breast cancer patients with painful bone metastases was safe and effective when administered concurrently with other standard therapies. In the future, the treatment with Sr-89 at the early stage should be considered, and a large-scale clinical study should be conducted.

Cancer to bone: a fatal attraction

When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and invasion, is central to the pathophysiology of bone metastases. Basic findings of tumour-bone interactions have uncovered numerous therapeutic opportunities that focus on the bone microenvironment to prevent and treat bone metastases.

Cancer to bone: a fatal attraction

When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and invasion, is central to the pathophysiology of bone metastases. Basic findings of tumour-bone interactions have uncovered numerous therapeutic opportunities that focus on the bone microenvironment to prevent and treat bone metastases.

Safety and feasibility of percutaneous vertebroplasty with radioactive (153)Sm PMMA in an animal model

PURPOSE

We investigated the safety and feasibility of the combination of samarium-153-ethylenediamine tetramethylene phosphonate ((153)Sm-EDTMP)-incorporated bone cement (BC) with percutaneous vertebroplasty (PVP) in dogs.

METHODS AND MATERIALS

(153)Sm-EDTMP-incorporated BC was prepared by combining solid (153)Sm-EDTMP and polymethylmethacrylate (PMMA) immediately before PVP. It was then injected into the vertebrae of four healthy mongrel dogs (two males and two females) by PVP under CT guidance. Each dog was subjected to five PVP sessions at a (153)Sm-EDTMP dose of 30-70 mCi. The suppressive effect of local injection of (153)Sm-EDTMP on the hematopoietic system was evaluated through counting of peripheral blood cells. Distribution of (153)Sm-EDTMP-incorporated BC and the status of tissues adjacent to injected vertebrae were evaluated with SPECT, CT and MRI. Histopathology was carried out to assess the influence of PVP on the vertebra and adjacent tissues at the microscopic level.

RESULTS

PVP was done successfully, and all dogs exhibited normal behavior and stable physical signs after procedures. (153)Sm-EDTMP-incorporated BC was concentrated mainly in target vertebrae, and the peripheral blood cells remained within normal range. The spinal cord and tissues around BC did not exhibit signs of injury even when the dosage of (153)Sm-EDTMP increased from 30 mCi to 70 mCi.

CONCLUSION

A dose lower than 70 mCi of (153)Sm is safe when it was injected into vertebrae. (153)Sm-EDTMP-incorporated BC did not influence the effect of PVP. This means might strengthen anti-tumor activity locally for vertebra with osseous metastasis without damaging adjacent tissues.

Phase I trial of vertebral intracavitary cement and samarium (VICS): novel technique for treatment of painful vertebral metastasis

PURPOSE

Kyphoplasty is an effective procedure to alleviate pain in vertebral metastases. However, it has no proven anticancer activity. Samarium-153-ethylene diamine tetramethylene phosphonate ((153)Sm-EDTMP) is used for palliative treatment of bone metastases. A standard dose of 1 mCi/kg is administrated intravenously. The present study was conducted to determine the feasibility of intravertebral administration of (153)Sm with kyphoplasty.

METHODS AND MATERIALS

A total of 33 procedures were performed in 26 patients. Of these 26 patients, 7 underwent procedures performed at two vertebral levels. The mean age of the cohort was 64 years (range, 33-86). The kyphoplasty procedure was performed using a known protocol; 1-4 mCi of (153)Sm was admixed with the bone cement and administered under tight radiation safety measures. Serial nuclear body scans were obtained. Pain assessment was evaluated using a visual analog pain score.

RESULTS

All patients tolerated the procedure well. No procedure-related morbidities were noted. No significant change had occurred in the blood counts at 1 month after the procedure. One case was not technically satisfactory. Nuclear scans revealed clear radiotracer uptake in the other 32 vertebrae injected. Except for the first patient, no radiation leakage was encountered. The mean pain score using the visual analog scale improved from 8.6 before to 2.8 after the procedure (p < .0001). Follow-up bone scans demonstrated a 43% decrease in the tracer uptake.

CONCLUSION

The results of our study have shown that the combination of intravertebral administration of (153)Sm and kyphoplasty is well tolerated with adequate pain control. No hematologic adverse effects were found. A reduction of the bone scan tracer uptake was observed in the injected vertebrae. Longer follow-up is needed to study the antineoplastic effect of the procedure.

Percutaneous tumor curettage and interstitial delivery of samarium-153 coupled with kyphoplasty for treatment of vertebral metastases

Object

The object of this study was to investigate the use of a minimally invasive technique for treating metastatic tumors of the vertebral body, aimed at relieving pain, preventing further tumor growth, and minimizing the adverse effects of systemic use of samarium-153 (153Sm).

Methods

The procedure is performed in the same fashion as a kyphoplasty, using a unilateral extrapedicular approach under local anesthesia/mild general sedation, with the patient in the lateral decubitus position. The tumor is accessed as in a standard kyphoplasty. The side is chosen according to the location of the metastasis. Prior to inflation of the balloon the tumor is debulked by percutaneous curettage. Balloon inflation is carried out as per standard kyphoplasty in an attempt to create a larger space and reduce a possible kyphotic deformity. Three mCi of 153Sm-EDTMP (ethylenediaminetetramethylenephosphonic acid) is then mixed with bone cement (polymethylmethacrylate) and injected into the void created by the balloon tamp.

Results

Twenty-four procedures were performed in 19 patients. There was reliable and reproducible delivery of the radiolabeled 153Sm-EDTMP to the metastatic site, without spillage. The procedure was safe. There were no procedure-related complications. There was no hematological toxicity with the low doses of 153Sm used. Pain improved in all patients. The long-term results related to tumor control continue to be investigated.

Conclusions

Combined percutaneous debulking of confined vertebral metastases and administration of local 153Sm is feasible and safe. Furthermore, this technique leads to immediate relief of cancer-related pain and may help prevent or slow down the progression of vertebral metastatic tumors.

Influence of human biokinetics of strontium on internal ingestion dose of 90Sr and absorbed dose of 89Sr to organs and metastases

The objective of the present work is to apply the plasma clearance parameters to strontium, previously determined in our laboratory, to improve the biokinetic and dosimetric models of strontium-90 ((90)Sr) used in radiological protection; and also to apply this data for the estimation of the radiation doses from strontium-89 ((89)Sr) after administration to patients for the treatment of the painful bone metastases. Plasma clearance and urinary excretion of stable strontium tracers of strontium-84 ((84)Sr) and strontium-86 ((86)Sr) were measured in GSF-National Research Center for Environment and Health (GSF) in 13 healthy German adult subjects after intravenous injection and oral administration. The biological half-life of strontium in plasma was evaluated from 49 plasma concentration data sets following intravenous injections. This value was used to determine the transfer rates from plasma to other organs and tissues. At the same time, the long-term retention of strontium in soft tissue and whole body was constrained to be consistent with measured values available. A physiological urinary path was integrated into the biokinetic model of strontium. Parameters were estimated using our own measured urinary excretion values. Retention and excretion of strontium were modeled using compartmental transfer rates published by the International Commission on Radiological Protection (ICRP), the SENES Oak Ridge Inc. (SENES), and the Urals Research Center for Radiation Medicine (TBM). The results were compared with values calculated by applying our GSF parameters (GSF). For the dose estimation of (89)Sr, a bone metastases model (GSF-M) was developed by adding a compartment, representing the metastases, into the strontium biokinetic model. The related parameters were evaluated based on measured data available in the literature. A set of biokinetic parameters was optimized to represent not only the early plasma kinetics of strontium but also the long-term retention measured in soft tissue and whole body. The ingestion dose coefficients of (90)Sr were computed and compared with different biokinetic model parameters. The ingestion dose coefficients were calculated as 2.8 x 10(-8), 2.1 x 10(-8), 2.5 x 10(-8) and 3.8 x 10(-8) Sv Bq(-1) for ICRP, SENES, TBM and GSF model parameters, respectively. Moreover, organ absorbed dose for the radiopharmaceutical of (89)Sr in bone metastases therapy was estimated based on the GSF and ICRP biokinetic model parameters. The effective doses were 3.3, 1.8 and 1.2 mSv MBq(-1) by GSF, GSF-M, and ICRP Publication 67 model parameters, respectively, compared to the value of 3.1 mSv MBq(-1) reported by ICRP Publication 80. The absorbed doses of red bone marrow and bone surface, 17 and 21 mGy MBq(-1) calculated by GSF parameters, and 7.1 and 8.8 mGy MBq(-1) by GSF-M parameters, are comparable to the clinical results of 3-19 mGy MBq(-1) for bone marrow and 16 mGy MBq(-1) for bone surface. Based on the GSF-M model, the absorbed dose of (89)Sr to metastases was estimated to be 434 mGy MBq(-1). The strontium clearance half-life of 0.25 h from the plasma obtained in the present study is obviously faster than the value of 1.1 h recommended by ICRP. There are no significant changes for ingestion dose coefficients of (90)Sr using different model parameters. A model including the metastases was particularly developed for dose estimation of (89)Sr treatment for the pain of bone metastases.

Radiobiology of systemic radiation therapy

Although systemic radionuclide therapy (SRT) is effective as a palliative therapy in patients with metastatic cancer, there has been limited success in expanding patterns of utilization and in bringing novel systemic radiotherapeutic agents to routine clinical use. Although there are many factors that contribute to this situation, we hypothesize that a better understanding of the radiobiology and mechanism of action of SRT will facilitate the development of future compounds and the future designs of prospective clinical trials. If these trials can be rationalized to the biological basis of the therapy, it is likely that the long-term outcome would be enhanced therapeutic efficacy. In this review, we provide perspectives of the current state of low-dose-rate (LDR) radiation research and offer linkages where appropriate with current clinical knowledge. These include the recently described phenomena of low-dose hyper-radiosensitivity-increased radioresistance (LDH-IRR), adaptive responses, and biological bystander effects. Each of these areas require a major reconsideration of existing models for radiation action and an understanding of how this knowledge will integrate into the evolution of clinical SRT practice. Validation of a role in vivo for both LDH-IRR and biological bystander effects in SRT would greatly impact the way we would assess therapeutic response to SRT, the design of clinical trials of novel SRT radiopharmaceuticals, and risk estimates for both therapeutic and diagnostic radiopharmaceuticals. We believe that the current state of research in LDR effects offers a major opportunity to the nuclear medicine community to address the basic science of clinical SRT practice, to use this new knowledge to expand the use and roles of SRT, and to facilitate the introduction of new therapeutic radiopharmaceuticals.

89Sr versus 153Sm-EDTMP: Comparison of treatment efficacy of painful bone metastases in prostate and breast carcinoma

BACKGROUND AND AIM

Painful bone metastases are most frequent in patients with advanced prostate or breast carcinoma. The aim of this study was to compare the analgesic effect of radionuclide therapy using Sr and Sm-EDTMP in patients with painful bone metastases of these tumours.

MATERIAL AND METHODS

One hundred patients treated with radionuclide bone palliation therapy were analysed. The study population consisted of 60 male patients with advanced prostate carcinoma and 40 female patients with advanced breast carcinoma. Fifty patients (30 men and 20 women) were treated with Sr (150 MBq). The other 50 patients were treated with Sm-EDTMP (37 MBq x kg). The treatment efficacy was evaluated by a visual analogue scale (VAS), Karnofsky performance scale, and dosage of analgesic drugs used.

RESULTS

Complete pain relief was found in 40% of women and 40% of men treated using Sm-EDTMP and in 25% of women and 33% of men treated with Sr. No analgesic effect occurred in 20% of patients. A better analgesic effect was found in cases of osteoblastic metastases compared to mixed metastases. Statistically significant reduction of pain intensity, use of analgesic drugs and improvement of performance in Karnofsky scale was found in cases of both radionuclides.

CONCLUSIONS

The analgesic effects of Sr and Sm-EDTMP was similar in both prostate and breast carcinoma. However, the effect was dependent on the type of metastases; better response was observed in cases of osteoblastic metastases than in patients with mixed metastases. Severe adverse reactions after this therapy were rare.

Prospective Evaluation of Samarium-153-EDTMP Radionuclide Treatment for Bone Metastases in Patients with Hormone-Refractory Prostate Cancer

PURPOSE

Bone is a common site of metastatic disease and the most frequent site of metastatic spread in patients with prostate cancer. Most patients with bone metastases complain of bone pains. This pain may be alleviated or eliminated by administration of radiotherapy at the site of metastases. Currently, two forms of radiotherapy administration exist: external-beam irradiation or intravenous administration of bone-seeking therapeutic radiopharmacon such as samarium-153-ethylene-diamino-tetramethylene-phosphonate (EDTMP). This radiopharmacon produces beta-particles and concentrates in the areas of enhanced osteoblastic activity. The aim of this study was to assess the efficacy of (153)Sm-EDTMP therapy.

MATERIALS AND METHODS

32 men (aged 50-83, mean 70 years) with bone disseminated hormone-refractory prostate cancer and bone pain received (153)Sm-EDTMP. Mean applied dosage was 40 MBq/kg of the patient's body weight. Karnofsky performance status, pain score (numerical rating scale), analgesic score (WHO) and blood count were evaluated before, and 1 and 3 months after the treatment.

RESULTS

Significant pain relief was observed in 44 and 38% of patients, mild relief in 31 and 34% and no effect in 25 and 28% of patients, 1 and 3 months after administration, respectively. Pain palliation was accompanied by an improvement in mobility and a decrease in necessary dosage of analgesics. Mild and transient bone marrow suppression was observed as a side effect of (153)Sm-EDTMP treatment. None of the patients showed hematological toxicity grade 4, and only 2 showed grade 3 (NCI CTC). The majority of the patients had hematological toxicity grade 1 or 2.

CONCLUSION

After (153)Sm-EDTMP administration, bone pain palliation was observed in 72% of patients for 3 months. Hematological toxicity after (153)Sm-EDTMP treatment was mild and transient.

Assessment of 186Re chelate-conjugated bisphosphonate for the development of new radiopharmaceuticals for bones

INTRODUCTION

The preferable pharmacokinetics of rhenium-186 (186Re)-monoaminemonoamidedithiol-conjugated or 186Re-mercaptoacetyltriglycine-conjugated bisphosphonates (BPs) suggested that the molecular design would be applicable to other radionuclides such as 68Ga, 99mTc, 153Sm and 177Lu. In this study, a key factor affecting the pharmacokinetics of a chelate-conjugated BP was investigated to estimate the validity and the applicability of molecular design.

METHODS

Chemically inert and well-characterized tricarbonyl[186Re][(cyclopentadienylcarbonyl amino)-acetic acid]rhenium ([186Re]CpTR-Gly) was conjugated with 3-amino-1-hydroxypropylidene-1,1-bisphosphonate and purified by high-performance liquid chromatography (HPLC) to prepare [186Re](1-{3-[tricarbonyl(cyclopentadienylcarbonyl amino)-acetylamido]-1-hydroxy-1-phosphono-propyl}-phosphonic acid)rhenium ([186Re]CpTR-Gly-APD). Plasma stability, plasma protein binding, hydroxyapatite (HA) binding and the pharmacokinetics of [186Re]CpTR-Gly-APD were compared with those of 186Re 1-hydroxyethylidene-1,1-diphosphonate (HEDP). The effect of HEDP coadministration and preadministration on the pharmacokinetics of [186Re]CpTR-Gly-APD was also determined.

RESULTS

The HPLC-purified [186Re]CpTR-Gly-APD showed higher plasma stability, higher HA binding, higher bone accumulation and lower plasma protein binding than did 186Re-HEDP. However, HA binding of [186Re]CpTR-Gly-APD decreased to levels slightly higher than that of 186Re-HEDP at similar HEDP concentrations. Bone accumulation of [186Re]CpTR-Gly-APD also decreased to levels similar to that of 186Re-HEDP when [186Re]CpTR-Gly-APD was coinjected with HEDP equivalent to that in 186Re-HEDP. In contrast, HEDP pretreatment did not impair bone accumulation of the two 186Re-labeled compounds. However, a delay in blood clearance and an increase in renal radioactivity levels were observed particularly with 186Re-HEDP.

CONCLUSIONS

Although 186Re-HEDP possessed HA binding and bone accumulation similar to those of [186Re]CpTR-Gly-APD, the specific activity of 186Re-labeled BPs was found to play a crucial role in bone accumulation and blood clearance. Thus, the molecular design of chelate-conjugated BP would be useful for the development of bone-seeking radiopharmaceuticals with a variety of radionuclides by selecting chelating molecules that provide high specific activities.

"Naked" radiopharmaceuticals

The term "naked" radiopharmaceuticals, more appropriately, "unbound" radiopharmaceuticals, refers to any radioisotope used for clinical research or clinical purposes that is not attached to a chemical or biological carrier, and that localizes in various tissues because of a physiologic or chemical propensity/affinity, or secondary to focal anatomic placement. Although they remain useful in selected clinical circumstances, the available agents (except for Iodine-131) have been relegated to an unfortunate and somewhat secondary role. The agents remain useful and worthy of consideration for new clinical investigation and clinical use.

Clinical Role of Sm-153 EDTMP in the Treatment of Painful Bone Metastatic Disease

PURPOSE

Sm-153 EDTMP is an effective treatment of painful bone metastases from different neoplasms. However, there are few studies describing clinical experience with this therapeutic modality. The aim of this clinical study was to evaluate the efficacy of Sm-153 EDTMP in a group of patients with skeletal metastases and poor pain control with conventional therapies.

MATERIALS AND METHODS

Sixty-four patients with painful bone metastases treated with Sm-153 EDTMP were retrospectively evaluated. Nine patients were treated twice. The most common primaries were breast in 28 cases (44%) and prostate in 27 (41%). Treatment efficacy was assessed by a visual analog scale, analgesic consumption, and performance status before and after treatment. Response was graded as complete, moderate, or minor. Toxicity evaluation included analytic parameters (blood counts, renal function) and clinical follow up.

RESULTS

Efficacy and toxicity were evaluated separately for each dose (total doses: 73), and complete follow up was only possible in 62 of 73 administrations. The response rate was 85% (21% complete, 40% moderate, and 24% minor). Onset of improvement took place a median of 7 days after Sm-153 EDTMP administration, and pain relief persisted for a mean of 3 months. No relevant toxicity was found in the early phase. Myelotoxicity appeared in 29% of the administrations and was mild in most cases (there was one case of grade 4 leukopenia).

CONCLUSIONS

Sm-153 EDTMP is a good therapeutic option for patients with painful bone metastases. It is an effective treatment of pain relief without major secondary effects.

Samarium for osteoblastic bone metastases and osteosarcoma

Samarium-153 lexidronam (153Sm-EDTMP) is FDA approved for painful osteoblastic bone metastases that image on bone scan. 153Sm-EDTMP decay has a therapeutic beta-emission and a gamma-photon for bone scan imaging. Monitoring of osteosarcoma radiation treatment effectiveness was performed with bone, CT, MRI and PET/CT fusion imaging. Bone scan and PET/CT improved in 5 out of 9 and 16 out of 18 osteosarcoma sites, respectively. 153Sm-EDTMP targets multiple sites of disease, with a single administration. Side effects of 153Sm-EDTMP (0.5-2.5 mCi/kg) have been minimal and include transient thrombocytopenia and neutropenia. 153Sm-EDTMP can be combined with radiation therapy, bisphosphonates and/or chemotherapy to synergistically improve palliation. This article reviews the rationale, indications and monitoring of standard-dose samarium and investigational high-dose 153Sm-EDTMP treatment of cancer involving bone.

Rhemium-186-monoaminemonoamidedithiol-conjugated bisphosphonate derivatives for bone pain palliation

To develop a radiopharmaceutical for the palliation of painful bone metastases based on the concept of bifunctional radiopharmaceuticals, we synthesized a bisphosphonate derivative labeled with rhenium-186 (186Re) that contains a hydroxyl group at the central carbon of its bisphosphonate structure, we attached a stable 186Re-MAMA chelate to the amino group of a 4-amino butylidene-bisphosphonate derivative [N-[2-[[4-[(4-hydroxy-4,4-diphosphonobutyl)amino]-4-oxobutyl]-2-thioethylamino]acetyl]-2-aminoethanethiolate] oxorhenium (V) (186Re-MAMA-HBP) and we investigated the effect of a hydroxyl group at the central carbon of its bisphosphonate structure on affinity for hydroxyapatite and on biodistribution by conducting a comparative study with [N-[2-[[3-(3,3-diphosphonopropylcarbamoyl)propyl]-2-thioethylamino]acetyl]-2-aminoethanethiolate] oxorhenium (V) (186Re-MAMA-BP). The precursor of 186Re-MAMA-HBP, trityl (Tr)-MAMA-HBP, was obtained by coupling a Tr-MAMA derivative to 4-amino-1-hydroxybutylidene-1,1-bisphosphonate. 186Re-MAMA-HBP was prepared by a reaction with 186ReO(4-) and SnCl2 in citrate buffer after the deprotection of the Tr groups of Tr-MAMA-HBP. After reversed-phase high-performance liquid chromatography, 186Re-MAMA-HBP had a radiochemical purity of over 95%. Compared with 186Re-MAMA-BP, 186Re-MAMA-HBP showed a greater affinity for hydroxyapatite beads in vitro and accumulated a significantly higher level in the femur in vivo. Thus, the introduction of a hydroxyl group into 186Re complex-conjugated bisphosphonates would be effective in enhancing accumulation in bones. These findings provide useful information on the design of bone-seeking therapeutic radiopharmaceuticals.

Palliative radiation therapy in oncology

Palliative radiation therapy is considered when the incurable cancer patient has symptoms specifically related to a malignancy that may be relieved by localized treatment of the primary tumor or metastatic lesions. Developing a treatment plan with radiation in the palliative setting may be more difficult than the curative setting, where there are clear guidelines for many situations. Radiation therapy has been used successfully in the management of a variety of pain syndromes. Radiation also has proven effective in the management of other tumor-related symptoms, including bleeding, neurologic compromise, dysphagia, and airway obstruction. Palliative radiation can be delivered using a variety of techniques: external beam radiation therapy, intraluminal brachytherapy (radioactive seed delivery), and systemic radionucleotides.

Recent Developments in Nuclear Medicine in the Management of Bone Metastases

OBJECTIVE

To review recent developments and to examine the role of nuclear medicine-based radionuclide therapy in the management of bone metastases.

METHODS

Recent developments in the use of radionuclides were broadly reviewed in the context of treatment paradigms, radionuclide toxicity, cost, and overall outcomes, and an impression of the use of radionuclides in metastatic bone disease was derived.

RESULTS

Through a number of studies, radionuclide therapy has been shown to be an efficacious and cost-effective means of alleviating bone pain in metastatic disease. Moreover, its early use in pain therapy may limit cancer progression by inhibiting oligometastases. Thus, radionuclides can significantly decrease patient morbidity, increase patient survival, and perhaps attenuate the aggressiveness of cancer. Nonetheless, in comparison with analgesics, external beam radiotherapy, or surgery, it still appears to have lower priority among medical oncologists.

CONCLUSION

Bone pain palliation is critical for cancer patients afflicted with bone metastases, but radionuclides remain underutilized in such treatments. The authors propose that physician education regarding radionuclide therapy be improved and additional investigations to evaluate newer radionuclides and treatment paradigms (eg, higher activities, repetitive or cyclic administration, chemosensitization, or chemosupplementation) be strongly encouraged. A comprehensive and an interdisciplinary clinical approach toward increasing the use of radionuclides in alleviating metastatic bone pain is proposed. Data from clinical collaborations will help optimize radiopharmaceutical therapy for pain palliation, increase its awareness among oncologists, and contribute effectively to patient palliation and quality-of-life improvements.

Management of bone metastases in cancer: a review

The presence of bone metastases is indicative of disseminated disease and typically indicates a short-term prognosis in cancer patients. Palliation of symptoms is the primary goal of therapy, with multidisciplinary efforts yielding the best results. New classes of drugs, such as bisphosphonates that significantly increase the time to first skeletal-related event (SRE), represent useful tools for the treatment of bone metastases. While the optimal duration of therapy needs to be defined, there is clinical benefit derived from the use of this class of agents. A potential role for bisphosphonates in the prevention of bone metastases is under current evaluation in clinical trials encompassing different solid tumor types. In combination with ongoing clinical trials, basic research to identify potential novel targets in the tumor cells-bone microenvironment will further define future strategies in the treatment of bone metastases.

Emerging analgesics in cancer pain management

Cancer pain is one of the most frequent symptoms in malignant disease, severely impairing the patients' quality of life. The recommendations of the World Health Organization will provide adequate pain relief for the vast majority of cancer patients. However, some patients will suffer from inadequate analgesia or intolerable side effects. Cyclooxygenase-2 (COX-2)-selective non-steroidal anti-inflammatory drugs (NSAIDs), new anticonvulsants, cannabinoids and NMDA receptor antagonists are being developed for these patients. NSAIDs with nitric oxide-releasing moieties are an interesting addition, as this new class of analgesics combines improved analgesic efficacy with higher tolerability. Conotoxins and other drugs such as nicotinic acetylcholinergic receptor agonists will be advantageous only for a few patients in the near future, as side-effect profile and risk of complications, as well as the burden on the patient, often are not worth the additional analgesic benefit.

Treatment of bone pain secondary to metastases using samarium-153-EDTMP

CONTEXT

More than 50% of patients with prostate, breast or lung cancer will develop painful bone metastases. The purpose of treating bone metastases is to relieve pain, reduce the use of steroids and to maintain motion.

OBJECTIVE

To evaluate the use of samarium-153-EDTMP (153Sm-EDTMP) for the treatment of bone pain secondary to metastases that is refractory to clinical management.

TYPE OF STUDY

Retrospective.

SETTING

Division of Nuclear Medicine, Universidade Estadual de Campinas (Unicamp).

METHODS

Fifty-eight patients were studied (34 males) with mean age 62 years; 31 patients had prostate cancer, 20 had breast cancer, three had lung cancer, one had lung hemangioendothelioma, one had parathyroid adenocarcinoma, one had osteosarcoma and one had an unknown primary tumor. All patients had multiple bone metastases demonstrated by bone scintigraphy using 99mTc-MDP,and were treated with 153Sm-EDTMP. Response to treatment was graded as good (pain reduction of 50-100%), intermediate (25-49%) and poor (0-24%).

RESULTS

All patients showed good uptake of 153Sm-EDTMP by bone metastases. Among the patients with prostate cancer, intermediate or good response to therapy occurred in 80.6% (25 patients) and poor response in 19.4% (6). Among the patients with breast cancer, 85% (17) showed intermediate or good response to therapy while 15% (3) showed poor response. All three patients with lung cancer showed poor response to treatment. The lung hemangioendothelioma and unknown primary lesion patients showed intermediate response to treatment; the osteosarcoma and parathyroid adenocarcinoma patients showed good response to treatment. No significant myelotoxicity occurred.

DISCUSSION

Pain control is important for improving the quality of life of patients with advanced cancers. The mechanism by which pain is relieved with the use of radionuclides is still not yet completely understood, however, the treatment is simple and provides a low risk of mielotoxicity.

CONCLUSION

Treatment with 153Sm-EDTMP can control the pain secondary to bone metastases effectively in most patients with breast and prostate cancer without significant side effects.

[Current multidisciplinary treatment of metastatic prostatic cancer]

Prostate cancer is one of the commonest causes of cancer-related death in the western world. The morbi-mortality associated is usually a direct consequence of metastatic spread to bone, in up to 50% of patients at first presentation. The aim of treatment of metastatic patients is to alleviate and to prevent the distressing symptoms. The approach include hormone-therapy, radiotherapy, radio-nuclides, surgery, chemotherapy, bisphosphonates and new drugs (agents that inhibit angiogenesis, immunotherapy and therapies that affect the differentiation). Decisions about therapy must also take into consideration the androgen-dependent or independent, so hormone-therapy is the first step of the treatment; the number and location of bone metastases; the severity of symptoms; the available of therapies; the status performance of patient; the prognosis and the cost-effect relationship. Some treatments have established indications whereas others are still in process of study in order to determinate their efficacy, their model of treatment and their indications. This article revises and updates these treatments.

Retrospective evaluation of bone pain palliation after samarium-153-EDTMP therapy

PURPOSE: The aim of this study was to evaluate the degree of metastatic bone pain palliation and medullar toxicity associated with samarium-153-EDTMP treatment. METHODS: Seventy-three patients with metastatic bone pain having previously undergone therapy with samarium-153-EDTMP (1 mCi/kg) were retrospectively evaluated. Routine follow-up included pain evaluation and blood counts for 2 months after treatment. Pain was evaluated using a subjective scale (from 0 to 10) before and for 8 weeks after the treatment. Blood counts were obtained before treatment and once a week for 2 months during follow-up. Dosimetry, based upon the urinary excretion of the isotope, was estimated in 41 individuals, and the resulting radiation absorbed doses were correlated with hematological data. RESULTS: Reduction in pain scores of 75% to 100% was obtained in 36 patients (49%), with a decrease of 50% to 75%, 25% to 50%, and 0% to 25% in, respectively, 20 (27%), 10 (14%), and 7 (10%) patients. There was no significant relationship between the pain response and location of the primary tumor (breast or prostate cancer). Mild to moderate myelosuppression was noted in 75.3% of patients, usually with hematological recovery at 8 weeks. The mean bone marrow dose was 347 ± 65 cGy, and only a weak correlation was found between absorbed dose and myelosuppression (Pearson coefficient = .4). CONCLUSIONS: Samarium-153-EDTMP is a valuable method for metastatic bone pain palliation. A mild to moderate and transitory myelosuppression is the main toxicity observed after samarium therapy, showing a weak correlation with dosimetric measures.

Radiotherapy plus either transdermal fentanyl or paracetamol and codeine for painful bone metastases: a randomised study of pain relief and quality of life

OBJECTIVE

To compare the effects of providing analgesia with either transdermal fentanyl (TTS-fentanyl) or paracetamol and codeine (P/C) in addition to radiotherapy in patients with metastatic bone pain.

METHODS

In a prospective study, 26 patients with radiologically confirmed bony metastases received radiotherapy (R/T). They were randomised to receive either 500 mg paracetamol and 30 mg codeine four times per day (P/C group), or transdermal fentanyl patches delivering 25 microg fentanyl/h (TTS-fentanyl group). Pain was assessed using visual analogue pain ratings (VAS) and the Greek Brief Pain Inventory (G-BPI) questionnaire administered before R/T and after 3 months.

RESULTS

Data were available from 24 eligible patients. Use of TTS-fentanyl was associated with significantly superior pain relief. Mean VAS fell from 7.0 to 1.1 with TTS-fentanyl and from 8.3 to 4.3 with P/C, p< 0.01. The TTS-fentanyl group also showed significantly greater improvements of important G-BPI domains including global quality of life, pain, and physical, cognitive, and role functioning, than the P/C group (p< 0.01). Four patients receiving TTS-fentanyl and three receiving P/C reported severe nausea/vomiting.

CONCLUSIONS

Transdermal fentanyl combined with R/T was more effective in reducing metastatic bone pain and resulted in greater improvements in quality of life than paracetamol and codeine.