strontium-radioisotopes and Spinal-Neoplasms

This contribution on the biology and management of bone metastases from prostatic cancer is divided into three parts. The first details a study conducted at Stanford University on the prevention of bone metastases in the lumbar spine, in patients in whom the lumbar spine has been irradiated coincidental to the radiation treatment of the paraaortic lymph nodes. The incidence of metastases was significantly reduced in 71 patients in whom the apparently normal lumbar spine was irradiated, as compared to the incidence of metastases in 65 patients who received no lumbar irradiation. The implications of these observations on developing strategies for early, or preemptive, irradiation for bone metastases are discussed. In the second part, the optimum radiation dose and fractionation scheme for the palliation of overt bone metastases is addressed. Drawing largely from the work of Arcangeli et al., a total dose of 40-50 Gy*, fractionated at 2 Gy per day, seems to be the regimen of choice for enduring pain relief for most patients with prostatic metastases to bone. Finally, the recent utilization of strontium-89 in the palliation of advanced bone metastases is addressed. *The Gy is the current international unit of radiation. 1Gy = 100 Rad; 1cGy (centigray) = 1 Rad.

Topics: Bone and Bones; Bone Neoplasms; Humans; Incidence; Life Tables; Lumbar Vertebrae; Lymphatic Metastasis; Male; Pain; Palliative Care; Pelvis; Prostatic Neoplasms; Radioisotope Teletherapy; Radiotherapy Dosage; Retrospective Studies; Spinal Neoplasms; Strontium Radioisotopes

We report measurements of absorbed dose to vertebral metastases in ten patients referred for 89Sr therapy for disseminated prostatic carcinoma. Patients received a tracer dose of 85Sr at the time of 89Sr treatment and metastatic strontium retention was monitored scintigraphically for 6 mo. Metastatic 85Sr activity corrected for tissue attenuation was measured using the conjugate view principle, with special care taken to eliminate errors due to the selection of the metastatic region of interest. Metastatic volume was determined from high resolution CT images, and density inferred from Hounsfield number using the QCT bone mineral calibration of Genant and Cann. The mean absorbed dose was 850 rad/mCi (23 cGy/MBq) with a range from 220-2260 rad/mCi (6 to 61 cGy/MBq). The wide range found was consistent with the variation expected to arise due to differences in strontium renal plasma clearance (range 0.1-11.81/day) and extent of skeletal metastatic disease (varying from two small metastases to a superscan on [99mTc]MDP images) among the patients studied.

Topics: Humans; Male; Prostatic Neoplasms; Radionuclide Imaging; Radiotherapy Dosage; Spinal Neoplasms; Spine; Strontium Radioisotopes

We present dosimetry for spinal metastases and red bone marrow in two patients who received 89Sr therapy for disseminated prostatic carcinoma. Absorbed dose to metastases was estimated by combining 85Sr gamma camera studies with computed tomographic measurements of bone mass, and doses of 20 cGy/MBq and 24 cGy/MBq were found for vertebral metastases that uniformly involved the bodies of L3 and D12 respectively. Absorbed dose to red bone marrow was estimated from total body strontium retention studies using the ICRP model for bone dosimetry, and a ratio of metastatic to marrow dose of around 10 was found in each patient. Although they received comparable treatment activities of around 200 MBq, the patients showed markedly different haematological response, this difference being confirmed when each received a second 89Sr treatment 6 months after the first. As a result, clinically significant thrombocytopenia occurred in one patient which prevented further radiostrontium therapy being given.

Topics: Adenocarcinoma; Aged; Bone Marrow Diseases; Brachytherapy; Energy Transfer; Follow-Up Studies; Hematologic Diseases; Humans; Male; Prostatic Neoplasms; Radiotherapy Dosage; Spinal Neoplasms; Strontium Radioisotopes; Tomography, X-Ray Computed; Whole-Body Counting

Amongst patients referred for 89Sr palliation of disseminated prostatic carcinoma, we have found wide variations in extent of skeletal metastatic disease and in strontium renal plasma clearance. A numerical technique using impulse response function analysis is reviewed which enables the effect of such variations on the total body, plasma and metastatic strontium retention functions to be calculated. The prediction of the model are compared with kinetic data from patients presenting for radiostrontium therapy, and correlations that have important implications for 89Sr dosimetric studies are confirmed. The simplest kinetic data required to allow for these effects in studies of dose-response and haematological toxicity following radio-strontium treatment are discussed and attention is drawn to a small group of patients who may form a significant exception to the general model.

Topics: Bone Neoplasms; Humans; Lumbar Vertebrae; Male; Metabolic Clearance Rate; Prostatic Neoplasms; Radiation Dosage; Spinal Neoplasms; Strontium Radioisotopes

Topics: Animals; Bone and Bones; Bone Neoplasms; Diphosphates; Diphosphonates; Dogs; Fluorine; Humans; Krypton; Neoplasm Transplantation; Neoplasms, Experimental; Rabbits; Radioisotopes; Radionuclide Imaging; Spinal Neoplasms; Strontium Radioisotopes; Technetium

Strontium 87m bone scanning was used in the assessment of 162 patients with breast cancer. Seventy-two patients had abnormal bone scans and in 63 (87 percent) these findings were subsequently confirmed. More metastases were detected by scanning and radiology than by radiology alone. There was a false positive rate of 7 percent. Of the 90 negative scans 23 showed evidence of metastasis either radiologically or at autopsy. This represented a false negative rate of 26 percent. The reasons for the false results are discussed particularly in relation to the problems of imaging the dorsal spine.

Topics: Bone Neoplasms; Breast Neoplasms; Diagnostic Errors; Female; Humans; Neoplasm Metastasis; Radiography; Radionuclide Imaging; Spinal Neoplasms; Strontium Radioisotopes

The value of bone scanning with 99mTc-polyphosphate was assessed in 186 patients with various types of tumors. The sensitivity of this technique was greater than that of metastatic roentgenographic series and the reported results of 85-Sr-bone scans, in the detection of osseous involvement by tumors. Three cases with normal bone scans and abnormal roentgenographic studies illustrated the necessity and complementary value of comparing bone scan findings with radiographic studies. Patients with carcinoma of the breast, lung, or prostate displayed characteristic patterns of bone involvement by their tumors. The importance of clinical information, including bone symptoms, antecedent bone disease, and serum calcium and alkaline phosphatase, was stressed in the detection and interpretation of bone scan abnormalities.

Topics: Alkaline Phosphatase; Bone Neoplasms; Breast Neoplasms; Evaluation Studies as Topic; Female; Humans; Hypercalcemia; Lung Neoplasms; Male; Middle Aged; Neoplasm Metastasis; Pelvic Neoplasms; Prostatic Neoplasms; Radionuclide Imaging; Ribs; Skull Neoplasms; Spinal Neoplasms; Strontium Radioisotopes; Technetium

Topics: Adolescent; Adult; Bone and Bones; Bone Diseases; Bone Neoplasms; Breast Neoplasms; Chondroma; Female; Fractures, Bone; Hodgkin Disease; Humans; Male; Middle Aged; Neoplasm Metastasis; Radionuclide Imaging; Sarcoma, Ewing; Spinal Neoplasms; Strontium Radioisotopes; Time Factors

Topics: Adult; Bone Neoplasms; Femoral Neoplasms; Half-Life; Humans; Male; Middle Aged; Phosphates; Radiography; Radioisotopes; Radionuclide Imaging; Spinal Neoplasms; Spine; Strontium Radioisotopes; Technetium

Topics: Bone Neoplasms; Breast Neoplasms; Feces; Female; Hodgkin Disease; Humans; Injections, Intravenous; Kinetics; Male; Neoplasm Metastasis; Osteolysis; Osteoporosis; Prostatic Neoplasms; Radionuclide Imaging; Spinal Neoplasms; Strontium; Strontium Radioisotopes; Time Factors

Topics: Acetabulum; Bone Neoplasms; Breast Neoplasms; Diagnosis, Differential; False Negative Reactions; Femoral Neoplasms; Half-Life; Humans; Lung Neoplasms; Neoplasm Metastasis; Osteoporosis; Pelvic Neoplasms; Posture; Pubic Bone; Radiography; Radionuclide Imaging; Ribs; Spinal Neoplasms; Strontium Radioisotopes

Topics: Animals; Bone Diseases; Bone Neoplasms; Bony Callus; Diagnosis, Differential; Female; Fractures, Bone; Half-Life; Humans; Injections, Intravenous; Male; Neoplasm Metastasis; Rabbits; Spinal Neoplasms; Strontium Radioisotopes

Topics: Child; Diagnosis, Differential; Female; Humans; Laminectomy; Lumbar Vertebrae; Myelography; Neuroblastoma; Radionuclide Imaging; Spinal Diseases; Spinal Neoplasms; Strontium Radioisotopes

Topics: Adolescent; Adult; Bone Neoplasms; Female; Gallium; Humans; Male; Middle Aged; Neoplasm Metastasis; Pelvic Neoplasms; Radioisotopes; Radionuclide Imaging; Spinal Neoplasms; Strontium Radioisotopes