succimer and Prostatic-Neoplasms

The frequency of bone metastases in individuals increases at advanced stages of cancer, mostly in patients suffering from lung, breast, or prostate cancer. The study aims to evaluate the effectiveness of bone metastases diagnosis of nuclear medicine, CT scan, and MRI in detecting bone metastases among patients with lung, breast, and prostate carcinoma.. Retrospective study design was adopted for the analysis of 120 recruited patients (with the presence of bone metastasis) following a series of examinations and tests.. Better sensitivity (73.33%) and specificity (94.66%) for MRI as compared to SPECT. MRI also proved to be more sensitive (68%) and specific (95.74%), as compared to the findings of the CT scan.. The results conclude that MRI provided favorable diagnostic performance for bone metastasis. It emphasizes that diagnosis using MRI may enable practitioners to devise optimal carcinoma treatment strategies. The healthcare practitioners need to assess the MRI findings to determine improved treatment plans.

Topics: Bone Neoplasms; Carcinoma; Humans; Magnetic Resonance Imaging; Male; Nuclear Medicine; Pentetic Acid; Prostatic Neoplasms; Retrospective Studies; Sensitivity and Specificity; Succimer

Rhenium-188 dimercaptosuccinic acid complex [188Re(V)DMSA], a potential therapeutic analogue of the tumour imaging agent 99mTc(V)DMSA, is selectively taken up in bone metastases in patients with prostate cancer. It would be helpful in planning palliative radionuclide therapy if 99mTc(V)DMSA could be used to predict tumour and kidney retention of 188Re(V)DMSA. The aim of this study was to determine the correlation between tumour-to-normal tissue ratios and kidney-to-soft tissue ratios of 99mTc(V)DMSA and 188Re(V)DMSA. This would determine whether a scan with 99mTc(V) DMSA could be used to identify patients for whom 188Re(V)DMSA treatment would be contra-indicated, and enable prediction of relative kidney and tumour radiation absorbed dose in 188Re(V)DMSA treatment. Ten patients with prostate carcinoma were recruited following observation of disseminated bone metastases on a recent 99mTc-hydroxydiphosphonate bone scan. Whole-body planar scans were obtained at ca. 4 h and 24 h after hydration and injection of 600 MBq 99mTc(V)DMSA, and a week later, at similar times after hydration and injection of 370 MBq 188Re(V)DMSA. A triple-energy window (TEW) scatter correction was applied to the 188Re scans. Counts per pixel were determined in regions of interest drawn over metastatic sites, kidneys and normal soft tissue. Tumour-to-soft tissue ratios were significantly lower (by a factor of approximately 0.8 after the TEW was applied) on 188Re scans than on 99mTc scans, but the two were highly linearly correlated both in all individual patients and in tumours pooled from all patients together both at 4 h and at 24 h. Kidney-to-soft tissue ratios were similarly correlated and were lower for 188Re than for 99mTc by a similar factor. Both tumour- and kidney-to-soft tissue ratios increased between 4 and 24 h but the latter increased more. In conclusion, only minor differences were seen between 99mTc and 188Re scans, and kidney-to-background ratios on 188Re scans were not higher than on 99mTc scans. These differences are insufficient to infer that they are due to a real difference in biodistribution, and they may be due only to different physical imaging characteristics. Thus 99mTc(V)DMSA scans are predictive of 188Re(V)DMSA biodistribution and could be used to estimate tumour and renal dosimetry and assess suitability of patients for 188Re(V)DMSA treatment.

Topics: Aged; Bone Neoplasms; Humans; Male; Middle Aged; Phantoms, Imaging; Prostatic Neoplasms; Radioisotopes; Radionuclide Imaging; Rhenium; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

Pentavalent rhenium-188 dimercaptosuccinic acid [188Re(V)DMSA] is a beta-emitting analogue of 99mTc(V)DMSA, a tracer that is taken up in a variety of tumours and bone metastases. The aim of this study was to develop the kit-based synthesis of the agent on a therapeutic scale, to assess its stability in vivo, and to obtain preliminary biodistribution and dosimetry estimates, prior to evaluation of its potential as a targeted radiotherapy agent. The organ distribution of 188Re in mice was determined 2 h after injection of 3 MBq 188Re(V)DMSA prepared from eluate from a 188W/188Re generator. Three patients with cancer of the prostate and three with cancer of the bronchus, all with bone metastases confirmed with a standard 99mTc-hydroxymethylene diphosphonate (99mTc-HDP) scan, were given 370 MBq 188Re(V)DMSA and imaged at 3 h and 24 h using the 155-keV gamma-photon (15%). Blood and urine samples were collected to determine clearance and to analyse the speciation of 188Re. Organ residence times were estimated from the scans, and used to estimate radiation doses using MIRDOSE 3. In mice, 188Re(V)DMSA was selective for bone and kidney. In patients, it showed selectivity for bone metastases (particularly those from prostate carcinoma) and kidney, but uptake in normal bone was not significantly greater than in surrounding soft tissues. Of the normal tissues the kidneys received the highest radiation dose (0.5-1.3 mGy/MBq). The images were strongly reminiscent of 99mTc(V)DMSA scans in similar patients. High-performance liquid chromatography analysis of blood and urine showed no evidence of 188Re in any chemical form other than 188Re(V)DMSA up to 24 h. In conclusion, 188Re(V)DMSA and its 186Re analogue warrant further clinical assessment as generator/kit-derived agents for treatment of painful bone metastases. These agents should also be assessed in medullary thyroid carcinoma and other soft tissue tumours which have been shown to accumulate 99mTc(V)DMSA.

Topics: Aged; Aged, 80 and over; Animals; Bone Neoplasms; Female; Humans; Lung Neoplasms; Male; Mice; Mice, Inbred BALB C; Middle Aged; Organometallic Compounds; Prostatic Neoplasms; Radiation Dosage; Radioisotopes; Radionuclide Imaging; Radiopharmaceuticals; Rhenium; Succimer; Tissue Distribution

99mTc(V)-DMSA labelled either by increasing the pH together with a low concentration of Sn, or by increasing the pH only are compared in vitro and in vivo. The gel chromatographic separation shows that after incubation with blood, all the 99mTc(V)-DMSA preparations are stable and do not bind to the plasma proteins. The behavior in rats as well as in clinical studies does not demonstrate any distinctive characteristics between the different radiomolecules. It seems that the pH of the solution is an important factor which controls the formation of 99mTc(V)-DMSA.

Topics: Animals; Bone Neoplasms; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Male; Organometallic Compounds; Prostatic Neoplasms; Radionuclide Imaging; Rats; Rats, Inbred Strains; Succimer; Sulfhydryl Compounds; Technetium Tc 99m Dimercaptosuccinic Acid; Tissue Distribution

Topics: Bone Neoplasms; Humans; Male; Prostatic Neoplasms; Radionuclide Imaging; Succimer; Sulfhydryl Compounds; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid

Topics: Adenocarcinoma; Aged; Bone Neoplasms; Humans; Male; Prostatic Neoplasms; Radionuclide Imaging; Succimer; Sulfhydryl Compounds; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid

Topics: Adult; Bone Neoplasms; Child; Humans; Hydronephrosis; Iodine Radioisotopes; Iodohippuric Acid; Kidney; Kidney Diseases; Kidney Diseases, Cystic; Male; Pentetic Acid; Prostatic Neoplasms; Radioisotope Renography; Succimer; Technetium