A Case of Success: Complete Response to Radium-223 in Metastatic Castration-Resistant Prostate Cancer.

Radium-223 dichloride (Ra223) is the first targeted alpha agent approved for treating metastatic castration-resistant prostate cancer (mCRPC) with bone-exclusive disease. A benefit in overall survival and time to the first symptomatic skeletal-related event was shown in the Alpharadin in Symptomatic Prostate Cancer Patients (ALSYMPCA) trial. However, this trial did not describe a bone scan response to Ra223, and there is no universal consensus about how it should be monitored. Furthermore, a scintigraphy flare phenomenon may lead to false-positive tracer uptake in responsive cases, thereby misleading the interpretation of imaging results.  We present the case of a 67-year-old male with mCRPC and exclusive bone disease treated with Ra223. The bone scintigraphy after the end of the treatment showed an apparent aggravation of the lesions, corresponding to a flare phenomenon, with an almost complete resolution after three months. The patient maintained a scintigraphic response for seven months.

Diagnostic and prognostic contribution of DPD scintigraphy in transthyretin V30M cardiac amyloidosis.

BACKGROUND: Early diagnosis and prognostic stratification of cardiac transthyretin amyloidosis are crucial. Although 99mTc 3,3-diphosphono-1,2-propanedicarboxylic acid (DPD) scintigraphy is the preferred method for the non-invasive diagnosis, its accuracy appears to be limited in transthyretin amyloidosis protein (ATTR) V30M mutation. Furthermore, its prognostic value in this mutation is unknown. This study investigated the diagnostic value of DPD scintigraphy to detect ATTR cardiomyopathy in V30M mutation and explored its prognostic value regarding mortality. METHODS: A total of 288 ATTR V30M mutation carriers (median age: 46 years; 49% males) without myocardial thickening (defined as septal thickness ≥13mm) attributable to other causes and who underwent DPD scintigraphy were enrolled. ATTR cardiomyopathy was defined by septal thickness ≥13mm and at least one of the criteria: late heart-to-mediastinum (H/M) 123I-metaiodobenzylguanidine (MIBG) uptake ratio <1.60; electrical heart disease or biopsy-documented amyloidosis. RESULTS: ATTR cardiomyopathy was identified in 41 (14.2%) patients and cardiac DPD uptake in 34 (11.8%). During a mean follow-up of 33.6 ± 1.2 months, 16 patients died (5.6%). Mortality was 14 times higher in patients with ATTR cardiomyopathy, 13 times higher in those with DPD uptake and 10 times higher in those with late H/M MIBG <1.60. The combined assessment of septal thickness and cardiac DPD uptake improved risk stratification: patients without septal thickening and without DPD retention had an excellent prognosis while those who presented either or both of them had a significantly worse prognosis, with 5-year mortality rates ranging from 39.9 to 53.3%. CONCLUSIONS: DPD scintigraphy is useful for prognostic stratification of ATTR V30M mutation carriers. Patients without septal thickening and no DPD uptake present the best prognosis compared to those with any signs of cardiac involvement.

The sensitivity of DPD scintigraphy to detect transthyretin cardiac amyloidosis in V30M mutation depends on the phenotypic expression of the disease.

Background: There is a growing need for a non-invasive test to detect cardiac involvement in patients with transthyretin-related hereditary amyloidosis (ATTR) caused by V30M mutation. 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy is a promising method, but its accuracy in this particular mutation remains unknown.Methods: A cohort of 179 patients: 92 with early-onset disease (EoD, symptoms <50-years-old), 33 with late-onset disease (LoD) and 54 asymptomatic carriers were prospectively evaluated and underwent DPD scintigraphy, which was compared with the results of echocardiogram, ambulatory blood pressure monitoring, 24 h-Holter, myocardial 123I-metaiodobenzylguanidine imaging and NT-proBNP.Results: Amyloid cardiomyopathy, defined as septal thickness ≥13 mm, was present in 32 patients (17.9%) and was more frequent in those with LoD (OR: 3.68, p = .003). Cardiac DPD uptake was present in 22 individuals (12.3%) and correlated with parameters indicative of cardiac amyloidosis. DPD imaging was strongly influenced by the age of disease onset: among patients with myocardial thickening, cardiac DPD retention was present in 11/15 (73.3%) with LoD, in contrast to only 4/17 (26.7%) with EoD (p = .005). Two patients with myocardial thickening and normal DPD scintigraphy underwent endomyocardial biopsy that confirmed ATTR amyloidosis.Conclusion: DPD scintigraphy presents suboptimal sensitivity to detect cardiac involvement in ATTRV30M, particularly in symptomatic patients with EoD.

Progression of myocardial sympathetic denervation assessed by 123I-MIBG imaging in familial amyloid polyneuropathy and the effect of liver transplantation. / Progressão da desnervação simpática cardíaca avaliada por cintigrafia com MIBG­I123 na polineuropatia amiloidótica familiar e o impacto da transplantação hepática.

INTRODUCTION: Familial amyloid polyneuropathy (FAP) is a rare disease caused by systemic deposition of amyloidogenic variants of the transthyretin (TTR) protein. The TTR-V30M mutation is caused by the substitution of valine by methionine at position 30 and mainly affects the peripheral and autonomic nervous systems. Cardiovascular manifestations are common and are due to autonomic denervation and to amyloid deposition in the heart. Cardiac sympathetic denervation detected by iodine-123 labeled metaiodobenzylguanidine (MIBG) is an important prognostic marker in TTR-V30M FAP. Liver transplantation, widely used to halt neurological involvement, appears to have a varying effect on the progression of amyloid cardiomyopathy. Its effect on the progression of cardiac denervation remains unknown. METHODS: In this observational study, patients with the TTR-V30M mutation underwent annual cardiac assessment and serial MIBG imaging with quantification of the late heart-to-mediastinum (H/M) ratio. RESULTS: We studied 232 patients (median age 40 years, 54.7% female, 37.9% asymptomatic at the time of inclusion) who were followed for a median of 4.5 years and underwent a total of 558 MIBG scans. During follow-up, 47 patients (20.3%) died. MIBG scintigraphy at inclusion was a strong predictor of prognosis, with the risk of death increasing by 27.8% for each one-tenth reduction in the late H/M ratio. The late H/M ratio decreased with age (0.082/year, p<0.001), but progression of cardiac denervation was so slow that annual repetition of MIBG imaging did not increase its prognostic accuracy. During follow-up, 70 symptomatic patients underwent liver transplantation. The late H/M ratio decreased by 0.19/year until transplantation but no statistically significant differences were detected after the procedure. CONCLUSIONS: Cardiac denervation is common during the progression of TTR-V30M FAP and quantification of the late H/M ratio on MIBG scintigraphy is valuable for prognostic stratification of these patients. Liver transplantation stabilizes cardiac denervation, without recovery or further deterioration in cardiac MIBG uptake after the procedure.

Reduced myocardial 123-iodine metaiodobenzylguanidine uptake: a prognostic marker in familial amyloid polyneuropathy.

BACKGROUND: Transthyretin familial amyloid polyneuropathy is a hereditary form of amyloidosis characterized by sensorimotor and autonomic neuropathy, cardiac conduction defects, and infiltrative cardiomyopathy. Previous studies have suggested that myocardial sympathetic denervation assessed by 123-iodine metaiodobenzylguanidine (MIBG) imaging occurs early in disease progression. However, its prognostic significance was never evaluated. We aimed to study the long-term prognostic value of myocardial sympathetic denervation detected by MIBG imaging in transthyretin familial amyloid polyneuropathy. METHODS AND RESULTS: A total of 143 individuals with V30M transthyretin mutation underwent Holter, ambulatory blood pressure monitoring, echocardiography, and MIBG imaging. Time to all-cause death was compared with late heart-to-mediastinum MIBG uptake ratio (H/M; either in relation to the estimated lower limit of normal [1.60] or as a continuous variable) using Cox proportional hazards regression. Multivariable analyses were performed to test the prognostic accuracy of clinical, neurological, and cardiovascular parameters. During a median follow-up of 5.5 years, 32 (22%) patients died. Five-year mortality rate was 42% for late H/M <1.60 and 7% for late H/M ≥1.60 (hazard ratio, 7.19; P<0.001). Late H/M was identified as an independent prognostic predictor. Fifty-three patients were submitted to liver transplantation. In comparison with neurophysiological score-matched controls, transplanted patients had lower long-term mortality (hazard ratio, 0.32; P=0.012). Patients with late H/M<1.60 were at higher risk of unfavorable outcome but seemed to have benefited from liver transplantation. CONCLUSIONS: Cardiac sympathetic denervation as assessed by MIBG imaging is a useful prognostic marker in transthyretin familial amyloid polyneuropathy.

[Reflex sympathetic dystrophy]. / Distrofia simpática reflexa.

Reflex Sympathetic Dystrophy is rare in pediatrics. It is a complex regional pain syndrome, of unknown etiology, usually post-traumatic, characterized by dysfunctions of the musculoskeletal, vascular and skin systems: severe persistent pain of a limb, sensory and vascular alterations, associated disability and psychosocial dysfunction. The diagnosis is based in high clinical suspection. In children and adolescents there are aspects that are different from the adult ones. Excessive tests may result in worsening of the clinical symptoms. Bone scintigraphy can help. Pain treatment is difficult, not specific. Physical therapies and relaxation technics give some relief. Depression must be treated. This syndrome includes fibromyalgia and complex regional pain syndrome type I. We present a clinical report of an adolescent girl, referred for pain, cold temperature, pallor and functional disability of an inferior limb, all signals disclosed by a minor trauma. She had been diagnosed depression the year before. The bone scintigraphy was a decisive test. The treatment with gabapentin, C vitamin, physiotherapy and pshycotherapy has been effective.

[Cost-effectiveness of samarium-153-EDTMP for the treatment of pain due to multiple bone metastases in hormone-refractory prostate cancer versus conventional pain therapy, in Portugal]. / Análise custo-efectividade do samário-153-EDTMP versus terapêutica convencional da dor em doentes com metástases ósseas múltiplas dolorosas em Portugal.

INTRODUCTION: Prostate cancer is a significant cause of morbidity and mortality. In Portugal alone, according to a study published in 2003, the rate of new prostate cancer cases were 53 per 100,000 men (in 2000), with an age-standardized mortality rate of about 28 per 100,000 (in 1995). Multiple bone metastases are one of the major complications of advanced prostate cancer. Samarium-EDTMP showed to be a safe and effective alternative for palliative treatment of bone metastases. The goal of this economic study is to assess the cost-effectiveness of Samarium-153-EDTMP for the treatment of pain due to multiple bone metastases in hormone-refractory prostate cancer versus conventional pain therapy, in Portugal. METHODOLOGY: Cost-effectiveness study that compares the expected direct costs to the National Health System of managing patients with painful multiple bone metastases with Samarium-153-EDTMP versus conventional pain therapy, in Portugal, in a 4-moths period. RESULTS: The total direct 4 months cost was 2,311.91 euro for a patient treated with Samarium-153-EDTMP versus 2,450.74 euro for a patient under standard treatment. According to the model a patient treated with Samarium-153-EDTMP represents a 138.83 euros saving. CONCLUSION: Samarium-153-EDTMP was not only a very effective therapeutic option but also an option with less cost than the conventional pain therapy, in patients with pain due to multiple bone metastases, in Portugal.

A new bis(3-hydroxy-4-pyridinone)-IDA derivative as a potential therapeutic chelating agent. Synthesis, metal-complexation and biological assays.

A new bis(3-hydroxy-4-pyridinone) derivative of iminodiacetic acid, imino-bis(acetyl(1-(3'-aminopropyl)-3-hydroxy-2-methyl-4-pyridinone)), IDAPr(3,4-HP)(2), has been prepared and studied in its interaction with a set of hard metal ions. This tetradentate ligand presents a much higher chelating efficiency for trivalent hard metal ions (Fe, Ga, Al) than the monodentate derivative Deferriprone, namely at the diluted conditions prevailing in physiological conditions and at low clinical doses. A similar behaviour was also observed for the complexation with Zn(II) but at a significantly lower extent. This compound presents a moderate hydrophilic character at physiological pH (logD=-1.72). In vivo assays showed much more rapid clearance of (67)Ga from most tissues of metal-loaded mice than the drug Deferriprone and the radioactivity excretion occurs mostly through the kidneys. Therefore, results from in vitro and in vivo studies indicated good perspectives for this compound to be a potential decorporating agent for hard metal ions in overload situations without depletion of essential metal ions such as zinc.

Early detection of sympathetic myocardial denervation in patients with familial amyloid polyneuropathy type I.

INTRODUCTION: Type I familial amyloid polyneuropathy (FAP I) is an autosomal dominant inherited disorder due to a genetic defect in transthyretin and is characterized by deposition of amyloid in various organs and tissues. The principal manifestations are related to polyneuropathy and dysautonomia. The aim of this study was to assess cardiac involvement and to correlate the findings with neurological status. METHODS: 34 patients with FAP (15 male and 19 female; mean age 43 +/- 15 years) underwent I123-labeled metaiodobenzylguanidine (MIBG) myocardial scintigraphy in order to evaluate cardiac sympathetic innervation. In addition they underwent ambulatory blood pressure monitoring (ABPM) and two-dimensional and Doppler echocardiography. Neurological involvement was quantified according to a neurophysiologic score (EMG; 0 = no abnormality and 100% = maximal disability). RESULTS: The mean value of cardiac MIBG uptake was 1.75 +/- 0.5 (normal = 2.6 +/- 0.3) and correlated inversely with the EMG score (r = -0.67; p = 0.001). In 27 (79%) of the 34 patients there was a decrease in MIBG accumulation, in 18 (53%) an alteration in the circadian BP pattern and/or an increase in systolic and/or diastolic BP loads at night, and in 17 (50%) left ventricular hypertrophy and/or diastolic dysfunction. Twenty-two patients were symptomatic and had a mean EMG score of 37.7 +/- 25% (group I). The remaining 12 were asymptomatic and without neurological involvement (group II). Group I was characterized by older age (48 +/- 15 vs. 33 +/- 10.2 years, p = 0.01), lower MIBG uptake (1.5 +/- 0.4 vs. 2.2 +/- 0.5, p = 0.001), higher systolic (129 +/- 16 vs. 119 +/- 6 mmHg, p = 0.01) and diastolic daytime BP (82 +/- 10 vs. 76 +/- 6 mmHg, p = 0.05), and higher systolic (119 +/- 17 vs. 105 +/- 7 mmHg, p = 0.01) and diastolic nocturnal BP (71 +/- 11 vs. 62 +/- 9 mmHg, p = 0.01) than patients in group II. In 21/22 patients in group I and in 6/12 in group II there was a decrease in cardiac MIBG activity. Sixteen patients in group I and 2 in group II had abnormal circadian BP pattern. Left ventricular hypertrophy was only seen in group I. CONCLUSIONS: Patients with FAP have a high incidence of cardiac denervation and an abnormal circadian BP pattern. These alterations in cardiac autonomic function precede the development of clinical manifestations and may be an important factor in determining the optimal timing for liver transplantation, which is currently the only way to control the progression of the disease.

Novel 3+1 mixed-ligand Technetium-99m complexes carrying dipeptides as monodentate ligands.

Novel mixed ligand oxotechnetium complexes of the type [99mTcO(SSS)(SR)], in which the SR monodentate ligand is derived from dipeptides gly-gly, phe-gly and ala-gly, have been synthesized. These complexes, which have a molecular weight above 300, a lipophilic moiety, [TcO(SSS)]+, and an ionizable group separated from the lipophilic moiety by a spacer, have been obtained in 70-95% radiochemical yield. These compounds were prepared using 99mTc-tartrate as the precursor and Sn2+ as the reducing agent. The identity of the [99mTcO(SSS)(SR)] complexes has been established by HPLC comparison with the analogous oxorhenium complexes. The nature of the monodentate co-ligand strongly affects the stability of the 99mTc-complexes and their biodistribution. Complex 3b is the most stable in vitro presenting the highest blood clearance, a high liver uptake and a selective hepatobiliary excretion (54.5% ID at 15 min post-injection, and 69.3% ID at 60 min post injection). The results obtained show that 3b have reasonable stability and in vivo properties that may be useful for peptide labeling.

Myocardial perfusion and angioplasty. Comparison of myocardial contrast echocardiography and scintigraphy.

OBJECTIVES: To estimate the efficacy of myocardial contrast echocardiography (MCE) by harmonic power imaging (HPI), in evaluation of perfusion in one-vessel coronary disease treated by angioplasty, using myocardial scintigraphy as gold standard. STUDY DESIGN: Prospective comparative study. SETTING: Ambulatory. POPULATION: We included 33 patients (pts), aged 53.5 +/- 9 years, 27 male. INCLUSION CRITERIA: pts with one-vessel coronary disease (> or = 70% stenosis), with indication for angioplasty; sinus rhythm; good echocardiographic window with harmonic imaging. Exclusion criterion: previous myocardial infarction. METHODS: All patients underwent myocardial scintigraphy and HPI together with stress echocardiography, both followed by angioplasty (stenting in ten). HPI and myocardial scintigraphy were repeated, in all patients, at three months after intervention. Ten patients were re-assessed by coronary angiography for ischemia on the scintigraphic study. For the HPI exam, Levovist was selected as contrast and dipyridamole as stress agent (0.56 mg/kg). Perfusion was assessed visually and classified by HPI and scintigraphy studies as: 1 (normal), 2 (reduced), or 3 (absent). For analysis, the left ventricle was divided into 16 segments. RESULTS: Of the 43 coronary angiograms performed (ten at three months after angioplasty), 38 showed 70% stenosis, none occlusive or subocclusive. We analyzed 1056 left ventricle segments, from 66 HPI and myocardial scintigraphy studies (before and after angioplasty). Analysis was impossible or doubtful in 4.9%. Baseline and stress HPI detected 216 perfusion abnormalities. Global concordance between the segmental perfusion score obtained by HPI and scintigraphy was 66.2%, which became 76.3% when two groups were considered: a) score 1 b) score 2 and 3 together. In comparison with scintigraphy, HPI sensitivity for detection of perfusion abnormalities was 79.3% (higher for anterior septum, anterior and lateral wall) and specificity was 91.4% (higher for septum, inferior wall and apical segments). HPI correctly identified the location of coronary stenosis in 73.5% of patients. CONCLUSIONS: In our study, HPI was a feasible and promising method for assessment of perfusion in one-vessel coronary disease and chronic ischemia. In comparison with myocardial scintigraphy, a high concordance for perfusion score was found, as well as high sensitivity and specificity for detection of perfusion abnormalities.

N-Carboxyalkyl derivatives of 3-hydroxy-4-pyridinones: synthesis, complexation with Fe(III), Al(III) and Ga(III) and in vivo evaluation.

A set of three N-carboxyalkyl 3-hydroxy-4-pyridinones has been studied as bidentate M(III) chelators (M=Fe, Al, Ga), with potential for oral administration. After preparation of the ligands, their protonation constants (log K(i)) and the stability constants of their metal complexes have been determined. The distribution coefficients of these compounds, between 1-octanol and Tris buffer pH 7.4, were measured. The effect of these compounds on the biodistribution of 67Ga-citrate loaded rats was investigated and compared with that of the administered 67Ga-complexes. Results indicated that, among these chelating agents, the N-carboxyethyl derivative has the highest affinity towards this set of metal ions, irrespective of the metal, and that it could even compete with transferrin, the main Fe-plasma protein. The binding affinity and the hydrophilic character decrease with the increase in the size of the alkylic chain. The biological assays indicate that the complex formation in vivo is characterized by a high kinetics and thermodynamic stability, suggesting a competition with the transferrin. All the ligands were found to enhance the excretion of the gallium. Noteworthy is the observed Ga bone fixation, mostly with the ethyl derivative, thus suggesting the potential use of the complex as a bone seeking agent.