State-of-the-art approaches to detecting early bone metastasis in prostate cancer

Upregulated PPARG2 facilitates interaction with demethylated AKAP12 gene promoter and suppresses proliferation in prostate cancer

Prostate cancer (PCA) is one of the most common male genitourinary tumors. However, the molecular mechanisms involved in the occurrence and progression of PCA have not been fully clarified. The present study aimed to investigate the biological function and molecular mechanism of the nuclear receptor peroxisome proliferator-activated receptor gamma 2 (PPARG2) in PCA. Our results revealed that PPARG2 was downregulated in PCA, and overexpression of PPARG2 inhibited cell migration, colony formation, invasion and induced cell cycle arrest of PCA cells in vitro. In addition, PPARG2 overexpression modulated the activation of the Akt signaling pathway, as well as inhibited tumor growth in vivo. Moreover, mechanistic analysis revealed that PPARG2 overexpression induced increased expression level of miR-200b-3p, which targeted 3′ UTR of the downstream targets DNMT3A/3B, and facilitated interaction with demethylated AKAP12 gene promoter and suppressed cell proliferation in PCA. Our findings provided the first evidence for a novel PPARG2-AKAP12 axis mediated epigenetic regulatory network. The study identified a molecular mechanism involving an epigenetic modification that could be possibly targeted as an antitumoral strategy against prostate cancer.

Extrapleural solitary fibrous tumor evidenced by 68Ga-prostate-specific membrane antigen positron emission tomography/computed tomography study in the staging of a high-risk prostate cancer patient

Positron emission tomography/computed tomography (PET/CT) using ⁶⁸Ga-labeled prostate-specific membrane antigen (⁶⁸Ga-PSMA) became an important tool in the prostate cancer (PC) diagnosis. Despite its high sensitivity and specificity, this method may produce false-positive findings, as indicated by previous studies. This case report aims to warn nuclear medicine physicians, oncologists, and urologists about the possibility of false-positive findings using this imaging modality, especially in patients who have already been diagnosed with other malignancies. A 69-year-old man, previously treated for an extrapleural solitary fibrous tumor (ESFT), underwent staging tests after a new diagnosis of high-risk PC. ⁶⁸Ga-PSMA PET/CT imaging revealed an abnormal uptake in the prostate and in the right humerus. A biopsy was performed, and the pathology showed a lesion consisting of an ESFT metastasis. Diagnostic issues related to ⁶⁸Ga-PSMA PET/CT imaging should be disseminated to help physicians make appropriate treatment choices for each patient and avoid unnecessary procedures.

68Ga-PSMA-PET/CT in comparison with 18F-fluoride-PET/CT and whole-body MRI for the detection of bone metastases in patients with prostate cancer: a prospective diagnostic accuracy study

OBJECTIVES

To determine the diagnostic accuracy of ⁶⁸gallium prostate-specific membrane antigen (PSMA)-based positron emission tomography/computed tomography (PET/CT) in comparison with ¹⁸F-fluoride-based PET/CT (NaF-PET/CT) and whole-body magnetic resonance imaging (WB-MRI) for the detection of bone metastases in patients with prostate cancer.

METHODS

Sixty patients with prostate cancer were included in the period May 2016 to June 2017. The participants underwent three scans (index tests) within 30 days: a NaF-PET/CT, a WB-MRI and a PSMA-PET/CT. Experienced specialists assessed the scans. In the absence of a histological reference standard, the final diagnosis was determined as a panel diagnosis. Measures of the diagnostic performances of the index tests were calculated from patient-based dichotomous outcomes (0 or ≥ 1 bone metastasis) and pairwise compared (McNemar test). For each index test, the agreement with the final diagnosis with regard to the number of bone metastases detected (0, 1-5, > 5) and the inter-reader agreement was calculated (kappa coefficients).

RESULTS

Fifty-five patients constituted the final study population; 20 patients (36%) were classified as having bone metastatic disease as their final diagnosis. The patient-based diagnostic performances were (sensitivity, specificity, overall accuracy) PSMA-PET/CT (100%, 100%, 100%), NaF-PET/CT (95%, 97%, 96%) and WB-MRI (80%, 83%, 82%). The overall accuracy of PSMA-PET/CT was significantly more favourable compared to WB-MRI (p = 0.004), but not to NaF-PET/CT (p = 0.48). PSMA-PET/CT classified the number of bone metastases reliably compared to the final diagnosis (kappa coefficient 0.97) and with an "almost perfect" inter-reader agreement (kappa coefficient 0.93).

CONCLUSIONS

The overall accuracy of PSMA-PET/CT was significantly more advantageous compared to WB-MRI, but not to NaF-PET/CT.

KEY POINTS

• PSMA-PET/CT assessed the presence of bone metastases correctly in all 55 patients • PSMA-PET/CT was more advantageous compared to WB-MRI • No difference was found between PSMA-PET/CT and NaF-PET/CT.

Multi-field-of-view SPECT is superior to whole-body scanning for assessing metastatic bone disease in patients with prostate cancer

Aim

The aim of this study was to compare the diagnostic performance of whole-body bone scintigraphy (WBS) and multi-field-of-view single photon emission tomography (multi-FOV SPECT) with 99mTc-oxidronate (99mTc-HDP) in patients with prostate cancer (PCa).

Methods

In a prospective study, WBS and SPECT acquisitions were performed in194 patients with histologically confirmed PCa and serum prostate-specific antigen (PSA) levels above 10 ng/mL. Scans obtained using the two modalities were interpreted separately. Clinical and biochemical follow-up, radiological studies and biopsies served as benchmarks for the assessments. The impact of PSA level on WBS and SPECT results was also evaluated.

Results

The patient-based sensitivity, specificity, accuracy, PPV and NPV values of SPECT examinations were higher than those of WBS, especially in patients with serum PSA levels ≶40 ng/mL.

Conclusion

Multi-FOV SPECT proved to be more sensitive and specific than WBS in detecting bone metastases in PCa patients.

Automated Bone Scan Index as Predictors of Survival in Prostate Cancer

Prostate cancer (PCa) is the second most diagnosed cancer in men. Early diagnosis and right management of PCa is critical to reducing deaths; the life expectancy is the main factors to be considered in the management of PCa. Among patients who die from PCa, the incidence of skeletal involvement appears to be >85%. Bone scan (BS) is the most common method for monitoring bone metastases in patients with PCa. The extent of bone metastasis was also associated with patient survival until now there is no clinically useful technique for measuring bone tumors and includes this information in the risk assessment. An alternative approach is to calculate a BS index (BSI) and it has shown clinical significance as a prognostic imaging biomarker. Some computer-assisted diagnosis (CAD) systems have been developed to measure BSI and are now available. The aim of this study was to investigate automated BSI (aBSI) measurements as predictors' survival in PCa. Retrospectively cohort studied fifty patients with PCa who had undergone BS between January 2010 and December 2011 at our institution. All data collected was updated up to August 2016. CAD system analyzing BS images to automatically compute BSI measurements. Patients were stratified into three BSI categories BSI value 0, BSI value ≤1 and BSI value >1. Kaplan-Meier estimates of the survival function and the log-rank test were used to indicate a significant difference between groups stratified in accordance with the BSI values. A total of 35 subjects deaths were registered, with a median survival time 36 months after the follow-up BS of 5 years. Subjects with low aBSI value had longer overall survival in comparison with the other subjects (P = 0.004). aBSI measurements were shown to be a strong prognostic survival indicator in PCa; survival is poor in high-BSI value.

Incremental diagnostic utility of systematic double-bed SPECT/CT for bone scintigraphy in initial staging of cancer patients

Background

SPECT/CT has been shown to increase the diagnostic performance of bone scintigraphy for staging of malignancies. A systematic double-bed SPECT/CT of the trunk may allow further improvement. However, this would be balanced by higher dosimetry and longer acquisition time. The objective was to assess the incremental diagnostic utility of a systematic double-bed SPECT/CT acquisition for bone scintigraphy in initial staging of cancer patients, especially compared with the usual approach consisting in a whole body planar scan (WBS) plus one single-bed targeted SPECT/CT.

Methods

One hundred two consecutive patients referred for bone scintigraphy for initial staging of malignancy were analyzed. All patients underwent a double-bed SPECT/CT acquisition of the trunk. Images were interpreted by two nuclear medicine physicians in a 3-step procedure. Firstly, only WBS planar images were used; secondly, one additional single-bed SPECT/CT chosen based on planar images was used; finally, WBS planar and double-bed SPECT/CT images were interpreted. Lesions were classified as benign, equivocal or suspicious for metastasis. A per-lesion, per-anatomical region and per-patient analysis was performed.

Results

In a per-lesion analysis, the number of equivocal and suspicious lesions was 91 and 241 using WBS planar images, 17 and 259 using a single-bed SPECT/CT acquisition and 11 and 269 using double-bed SPECT/CT images, respectively. In a per-patient analysis, the diagnostic conclusion was negative, equivocal or suspicious for malignancy in 35, 53 and 14 patients using WB planar images, 77, 6 and 19 patients using an additional single-bed SPECT/CT and 76, 7 and 19 using double-bed SPECT/CT images, respectively.

Seventeen lesions unseen on WBS images were interpreted as suspicious (n = 12) or equivocal (n = 5) on double-bed SPECT/CT images. Six lesions unseen on “WBS + targeted single-bed SPECT/CT” were interpreted as suspicious on double-bed SPECT/CT, with no shift in the metastatic status of patients.

Conclusion

A systematic double-bed SPECT/CT acquisition has a limited incremental diagnostic value over an oriented single-bed SPECT/CT in terms of specificity and conclusiveness of bone scintigraphy in the initial staging of cancer patients. However, it slightly improved the sensitivity of the test by detecting unseen lesions on WBS, which may be of value for initial staging of cancer.

Comparison between conventional imaging (abdominal-pelvic computed tomography and bone scan) and [(18)F]choline positron emission tomography/computed tomography imaging for the initial staging of patients with intermediate- tohigh-risk prostate cancer: A retrospective analysis

OBJECTIVE

The aim of this study was to evaluate the efficiency of [(18)F]fluorocholine positron emission tomography/computed tomography (FCH PET/CT) in detecting lymph-node and bone involvement in comparison with conventional imaging, such as abdominal-pelvic CT and bone scan, in the initial staging of prostate cancer (PCa).

MATERIALS AND METHODS

The study retrospectively evaluated 48 patients who had FCH PET/CT for the initial staging of PCa. At the same time, 32 of the 48 patients had a bone scan and 26 of the 48 patients had abdominal-pelvic diagnostic CT. Diagnostic performance of FCH PET/CT, i.e. sensitivity, specificity and accuracy, was evaluated on a per-patient basis for the whole population and then separately on a per-risk classification, and later in comparison with conventional imaging. Histological specimens or follow-up data were used as the standard of reference.

RESULTS

The overall accuracy of FCH PET/CT for lymph-node involvement was 83.3%. The sensitivity of FCH was higher in the high-risk subset (83.3%) than in the intermediate-risk group (33.3%), whereas FCH specificity was similar. In comparison with dedicated CT scan, FCH PET/CT showed a higher sensitivity and a similar specificity (46.2% vs 69.2% and 92.3% vs 92.3%, respectively). Moreover, the sensitivity and specificity of PET/CT were higher than those of bone scan (100% vs 90% and 86.4% vs 77.2%, respectively). In contrast with conventional imaging, PET/CT changed the staging of the PCa in 33.3% patients.

CONCLUSIONS

The efficiency of FCH PET/CT in detecting both bone and lymph-node involvement of PCa at initial staging was found to be higher than that of conventional imaging. Prospective clinical trials are needed to confirm these findings.

INPP4B suppresses prostate cancer cell invasion

BACKGROUND

INPP4B and PTEN dual specificity phosphatases are frequently lost during progression of prostate cancer to metastatic disease. We and others have previously shown that loss of INPP4B expression correlates with poor prognosis in multiple malignancies and with metastatic spread in prostate cancer.

RESULTS

We demonstrate that de novo expression of INPP4B in highly invasive human prostate carcinoma PC-3 cells suppresses their invasion both in vitro and in vivo. Using global gene expression analysis, we found that INPP4B regulates a number of genes associated with cell adhesion, the extracellular matrix, and the cytoskeleton. Importantly, de novo expressed INPP4B suppressed the proinflammatory chemokine IL-8 and induced PAK6. These genes were regulated in a reciprocal manner following downregulation of INPP4B in the independently derived INPP4B-positive LNCaP prostate cancer cell line. Inhibition of PI3K/Akt pathway, which is highly active in both PC-3 and LNCaP cells, did not reproduce INPP4B mediated suppression of IL-8 mRNA expression in either cell type. In contrast, inhibition of PKC signaling phenocopied INPP4B-mediated inhibitory effect on IL-8 in either prostate cancer cell line. In PC-3 cells, INPP4B overexpression caused a decline in the level of metastases associated BIRC5 protein, phosphorylation of PKC, and expression of the common PKC and IL-8 downstream target, COX-2. Reciprocally, COX-2 expression was increased in LNCaP cells following depletion of endogenous INPP4B.

CONCLUSION

Taken together, we discovered that INPP4B is a novel suppressor of oncogenic PKC signaling, further emphasizing the role of INPP4B in maintaining normal physiology of the prostate epithelium and suppressing metastatic potential of prostate tumors.

INPP4B suppresses prostate cancer cell invasion

Background

INPP4B and PTEN dual specificity phosphatases are frequently lost during progression of prostate cancer to metastatic disease. We and others have previously shown that loss of INPP4B expression correlates with poor prognosis in multiple malignancies and with metastatic spread in prostate cancer.

Results

We demonstrate that de novo expression of INPP4B in highly invasive human prostate carcinoma PC-3 cells suppresses their invasion both in vitro and in vivo. Using global gene expression analysis, we found that INPP4B regulates a number of genes associated with cell adhesion, the extracellular matrix, and the cytoskeleton. Importantly, de novo expressed INPP4B suppressed the proinflammatory chemokine IL-8 and induced PAK6. These genes were regulated in a reciprocal manner following downregulation of INPP4B in the independently derived INPP4B-positive LNCaP prostate cancer cell line. Inhibition of PI3K/Akt pathway, which is highly active in both PC-3 and LNCaP cells, did not reproduce INPP4B mediated suppression of IL-8 mRNA expression in either cell type. In contrast, inhibition of PKC signaling phenocopied INPP4B-mediated inhibitory effect on IL-8 in either prostate cancer cell line. In PC-3 cells, INPP4B overexpression caused a decline in the level of metastases associated BIRC5 protein, phosphorylation of PKC, and expression of the common PKC and IL-8 downstream target, COX-2. Reciprocally, COX-2 expression was increased in LNCaP cells following depletion of endogenous INPP4B.

Conclusion

Taken together, we discovered that INPP4B is a novel suppressor of oncogenic PKC signaling, further emphasizing the role of INPP4B in maintaining normal physiology of the prostate epithelium and suppressing metastatic potential of prostate tumors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12964-014-0061-y) contains supplementary material, which is available to authorized users.

Optimal bone health management strategies in patients with prostate cancer

Bone health is affected in patients with prostate cancer, both by the disease and its treatment. Metastases to bone leads to pain, fractures, and spinal cord compression; bone loss due to androgen deprivation therapy (ADT) leads to osteoporosis and its complications. Both these scenarios are a major cause of morbidity and adversely affect the quality of life of these patients. Maintaining an optimum bone health throughout the natural course of prostate cancer is an important aspect in the management of this disease. An understanding of the complex interplay between osteoclasts, osteoblasts, receptor activator of nuclear factor κB (RANK), and various other tyrosine kinases involved in the pathophysiology of bone metastases is essential. Zoledronic acid (ZA), an intravenously administered bisphosphonate, and Denosumab, a subcutaneously administered inhibitor of nuclear factor B ligand (RANKL), have already been approved by Food and Drug Administration (FDA) for their use in treatment of bone metastases. This article discusses the pathophysiology of bone metastases and bone loss due to ADT in prostate cancer, role of biomarkers, newer modalities of imaging, World Health Organization (WHO)/FRAX nomogram in evaluation of these patients, utility of currently available drugs and evidence supporting their use, and newer therapeutic agents like alpha-emitting Radium-223, endothelin-A receptor antagonists (Atrasentan and Zibotentan) and the proto-oncogene tyrosine-protein kinase (SRC) inhibitor, Dasatinib.

Bone metastases from prostate cancer: 18F-fluoride PET/CT in a patient with discordant bone scintigraphy and 11C-choline PET/CT

Bone scintigraphy has been used extensively in prostate cancer patients to detect bone involvement. (11)C-choline PET/CT is indicated when a biochemical recurrence is suspected, as this procedure is able to detect local recurrence, lymph-node infiltration, and metastases.In cases where the results of these 2 procedures do not coincide, MRI is then usually performed. (18)F-fluoride may become an alternative to MRI for bone imaging.In our patient series, all bone lesions with (11)C-choline uptake were metastases. (18)F-Fluoride did not increase specificity of (11)C-choline but increased sensitivity of bone scintigraphy. CT helped in the interpretation of osteoarthritis and trauma lesions.

[Imaging diagnostics of advanced prostate cancer]

The diagnostic approach to prostate cancer is still a big challenge for the treating physician. Regarding an individualized and risk-adapted evaluation of different therapeutic options, precise diagnostic tools are crucial to accurately distinguish between localized and advanced prostate cancer. Imaging of advanced prostate cancer is currently changing due to numerous technical innovations. While choline-based hybrid positron emission tomography-computed tomography (PET/CT) has been established as an important diagnostic tool in clinical imaging of advanced prostate cancer, well-investigated methods, such as magnetic resonance imaging (MRI) and bone scintigraphy are currently expanding the diagnostic potential due to technical improvements. The specific use of imaging for advanced prostate cancer may help to offer the patient a well-tailored oncologic therapy. Further research is needed to evaluate whether this individualized therapy can consistently improve the prognosis of patients suffering from advanced prostate cancer.

Prediction of survival benefit using an automated bone scan index in patients with castration-resistant prostate cancer

What's known on the subject? and What does the study add? A bone scan index (BSI) can quantify the extent of bone involvement and response to treatment, but it has not been widely accepted, because of its time-consuming nature. The study is the first to demonstrate that automated BSI calculated with a computer-assisted diagnosis system is effective in judging the chemotherapeutic response of bone metastatic lesions in patients with castration-resistant prostate cancer.

OBJECTIVE

• To evaluate the value of an automated bone scan index (aBSI), calculated using a computer-assisted diagnosis system, to indicate chemotherapy response and to predict prognosis in patients with castration-resistant prostate cancer (CRPC) with bone metastasis.

PATIENTS AND METHODS

• Forty-two consecutive CRPC patients underwent taxane-based chemotherapy between November 2004 and March 2011 at our institution. • The aBSIs were retrospectively calculated at the diagnosis of CRPC and 16 weeks after starting chemotherapy. • Cox proportional hazards regression models were applied to multivariate analyses with and without aBSI response in addition to the basic model. • Based on the difference in the concordance index (c-index) between each model, the prognostic relevance of adding the aBSI response was determined.

RESULTS

• A decrease in aBSI was found in 28 patients (66.7%), whereas a response was shown by bone scan in only 23.8% of patients. • Patients with a reduction in aBSI had longer overall survival (OS) in comparison with the other patients (P= 0.0157). • Multivariate analysis without aBSI response showed that performance status (P= 0.0182) and PSA response (P= 0.0375) were significant prognosticators. • By adding the aBSI response to this basic model, the prognostic relevance of the model was improved with an increase in the c-index from 0.621 to 0.660.

CONCLUSIONS

• The aBSI reflected the chemotherapy response in bone metastasis. • The index detected small changes of bone metastasis response as quantified values and was a strong prognostic indicator for patients with CRPC.

Study on the distribution features of bone metastases in prostate cancer

OBJECTIVES

The aim of this study was to explore the distribution features of metastatic bony lesions in prostate cancer.

MATERIALS AND METHODS

Bone scans with 99mTc-methylene diphosphonate were performed in 144 patients with pathologically proven prostate cancer, and distribution regularity of metastatic bony lesions was analyzed retrospectively.

RESULTS

A total of 2000 lesions of bone metastasis were detected in 102 patients, 28.9% of which were distributed in the ribs, 14.8% in thoracic vertebrae, 13.8% in the ilium, and 8.0% in the lumbar vertebrae. The distribution of metastatic bony lesions was correlated with the total number of lesions. The proportion of metastatic lesions of vertebrae and pelvis was up to 84.5% (49/58) in fewer bone metastases. The proportion gradually decreased with an increase in the total number of lesions, but the proportion of the bony lesions, except for the vertebrae and pelvis, gradually increased with an increase in the total number of lesions. Ninety-nine percent (903/912) of metastatic bony lesions, except for the vertebrae and pelvis, coexisted with metastasis of vertebrae or pelvis, whereas only 1.0% (9/912) of those were detected in no metastasis of the vertebrae and pelvis; their difference was significant (χ2=876.4, P=0.000). About 98.8% (571/578) of metastatic costal lesions coexisted with vertebrae metastasis, but only 1.2% (7/578) of these were detected in no metastasis of vertebrae; their difference was significant (χ2=550.3, P=0.000). The difference between left body and right body was not significant (χ=1.3, P=0.249).

CONCLUSION

Metastatic bony lesions of prostate cancer are located mainly in the vertebrae and pelvis in the early stage. The distribution of metastatic bony lesions is not only characterized by spreading to left body and right body randomly, but also presents the tendency of developing with orderliness to a certain extent in the whole body.

Imaging in prostate cancer staging: present role and future perspectives

Despite recent improvements in detection and treatment, prostate cancer continues to be the most common malignancy and the second leading cause of cancer-related mortality. Thus, although survival rate continues to improve, prostate cancer remains a compelling medical health problem. The major goal of prostate cancer imaging in the next decade will be more accurate disease characterization through the synthesis of anatomic, functional, and molecular imaging information in order to plan the most appropriate therapeutic strategy. No consensus exists regarding the use of imaging for evaluating primary prostate cancer. However, conventional and functional imaging are expanding their role in detection and local staging and, moreover, functional imaging is becoming of great importance in oncologic management and monitoring of therapy response. This review presents a multidisciplinary perspective on the role of conventional and functional imaging methods in prostate cancer staging.

Do all patients with newly diagnosed prostate cancer need staging radionuclide bone scan? A retrospective study

PURPOSE

Define a group of patients with newly diagnosed prostate cancer, whose risk of bone metastasis is low enough to omit a bone scan staging study.

MATERIALS AND METHODS

From 2003 to 2009, the medical records of patients who were newly diagnosed with prostate cancer were retrospectively reviewed. The data collected included: age, digital rectal examination, serum prostate specific antigen (PSA), Gleason score, clinical T stage, and bone isotope scan. Patients were divided into two groups according to the results of bone isotope scan; positive group and negative group. A univariate and multivariate binary logistic regression was used to analyze the results.

RESULTS

Of the 106 patients, 98 had a complete data collection and were entered into the study. The median age of the patients was 70.5 years and patients with a positive bone scan was 74 years, significantly higher than for patients with negative scans (69 years) (p=0.02). Bone metastasis was detected in 39 cases (39.7%). In all patients with clinical T1-2 stage, a Gleason score of <8 and PSA≤20 ng/mL, the bone isotope scans were negative. In univariate analysis, PSA (>20 ng/mL) and Gleason score (>7) were independently predictive of positive bone scan, while clinical stage was not.

CONCLUSION

Staging bone scans can be omitted in patients with a PSA level of ≤20 ng/mL, and Gleason score<8. Our results suggest that by considering the Gleason score and PSA, a larger proportion of patients with prostate cancer could avoid a staging bone scan.

Diagnosis of bone metastases in urological malignancies--an update

The spread of urological malignancies to bone is a poor prognostic factor. Early detection of metastatic bony lesions assists with tailoring patient management and potentially improving quality of life. Newer therapies such as zolderonic acid for prostate cancer have reinvigorated the importance of clinicians treating bony disease. An array of biochemical and imaging options are available and the order, sensitivity and cost of such investigations need to be understood to maximise clinical benefit. Furthermore, the ideal time to investigate for bony metastases has often been controversial. Although simple history and examination, serum calcium and alkaline phosphatase and plain radiography with bone scintigraphy remain at the forefront of diagnosing bony disease, evolving diagnostic modalities, such as positron emission tomography and newer bone markers need to be considered. The aim of this review is to clarify the role of various investigations and to give clinicians a current analysis of the timing of such investigations in the context of evolving diagnostic modalities and accepted guidelines for urological malignancy.

Magnetic resonance imaging of the axial skeleton for detecting bone metastases in patients with high-risk prostate cancer: diagnostic and cost-effectiveness and comparison with current detection strategies

PURPOSE

To evaluate the diagnostic performance, costs, and impact on therapy of one-step magnetic resonance imaging (MRI) of the axial skeleton (MRIas) for detecting bone metastases in patients with high-risk prostate cancer (PCa).

PATIENTS AND METHODS

Sixty-six consecutive patients with high-risk PCa prospectively underwent MRIas in addition to the standard sequential work-up (SW) of bone metastases (technetium-99m bone scintigraphy [BS] completed with targeted x-rays [TXR] in patients with equivocal BS findings and with MRI obtained on request [MRIor] in patients with inconclusive BS/TXR findings). Panel review of initial and 6-month follow-up MRI findings, BS/TXR, and all available baseline and follow-up clinical and biologic data were used as the best valuable comparator to define metastatic status. Diagnostic effectiveness of MRIas alone was compared with each step of the SW. Impact of MRIas screening on patient management and costs was evaluated.

RESULTS

On the basis of the best valuable comparator, 41 patients (62%) had bone metastases. Sensitivities were 46% for BS alone, 63% for BS/TXR, 83% for BS/TXR/MRIor, and 100% for MRIas; the corresponding specificities were 32%, 64%, 100%, and 88%, respectively. MRIas was significantly more sensitive than any other approach (P < .05, McNemar). MRIas identified metastases in seven (30%) of 23 patients considered negative and eight (47%) of 17 patients considered equivocal by other strategies, which altered the initially planned therapy. Economic impact was variable among countries, depending on reimbursement rates.

CONCLUSION

MRIas is more sensitive than the current SW of radiographically identified bone metastases in high-risk PCa patients, which impacts the clinical management of a significant proportion of patients.

Bone metastases are infrequent in patients with newly diagnosed prostate cancer: Analysis of their clinical and pathologic features

OBJECTIVES

To investigate the clinical and pathologic characteristics of patients with bone metastases identified at the time of newly diagnosed prostate carcinoma at biopsy.

METHODS

From November 2002 to May 2004, 1587 consecutive patients had a pathologic diagnosis of prostate cancer and underwent conventional technetium-99m methylene diphosphonate scintigraphy of the entire body. The clinical and pathologic features of those patients with positive bone scan findings (group 1) were compared with those of a subcohort of 372 patients with negative bone scan findings performed at the same nuclear medicine department (group 2).

RESULTS

A retrospective complete data collection was available for 1242 of 1587 patients. Bone metastases were found in 31 patients (2.5%). As expected, patients with skeletal metastases had a significantly greater mean serum total prostate-specific antigen level, and a Gleason sum of 8 or 9 was significantly more frequent in the pathologic findings of these subjects. Group 1 patients had a significantly greater prevalence of previous nonprostate primary neoplasms (chi-square 12.74, df = 1, P = 0.0004) and reported a greater prevalence of current use of H2 blockers for the treatment and prevention of gastroesophageal reflux disorders (chi-square 37.52, df = 1, P < 0.0001) than did group 2 patients.

CONCLUSIONS

Our data have confirmed that bone metastases are more frequent in patients with high prostate-specific antigen levels and poorly differentiated tumors at biopsy regardless of the patient's age. A history of previous nonprostate primary neoplasms and the use of H2 blockers seemed to be more prevalent in those patients with bone metastases at diagnosis.