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1.
J Nucl Med ; 60(11): 1531-1536, 2019 11.
Article in English | MEDLINE | ID: mdl-30954940

ABSTRACT

We evaluated 18F-fluciclovine uptake parameters that correlate with true positivity for local recurrence in non-prostatectomy-treated patients. Methods: Twenty-one patients (prostate-specific antigen level, 7.4 ± 6.8 ng/mL) with biochemical recurrence after nonprostatectomy local therapy (radiotherapy and cryotherapy) underwent dual-time-point 18F-fluciclovine (364.1 ± 37.7 MBq) PET/CT from pelvis to diaphragm. Prostatic uptake over background was delineated and coregistered to a prostate-biopsy-planning ultrasound. Transrectal biopsies of 18F-fluciclovine-defined targets were completed using a 3-dimensional visualization and navigation platform. Histologic analyses of lesions were completed. Lesion characteristics including SUVmax, target-to-background ratio (TBR), uptake pattern, and subjective reader's suspicion level were compared between true-positive (malignant) and false-positive (benign) lesions. Univariate analysis was used to determine the association between PET and histologic findings. Receiver-operating-characteristic curves were plotted to determine discriminatory cutoffs for TBR. Statistical significance was set at a P value of less than 0.05. Results: Fifty lesions were identified in 21 patients on PET. Seventeen of 50 (34.0%) targeted lesions in 10 of 21 patients were positive for malignancy. True-positive lesions had a significantly higher SUVmax (6.62 ± 1.70 vs. 4.92 ± 1.27), marrow TBR (2.57 ± 0.81 vs. 1.69 ± 0.51), and blood-pool TBR (4.10 ± 1.17 vs. 2.99 ± 1.01) than false-positive lesions at the early time point (P < 0.01) and remained significant at the delayed time point, except for blood-pool TBR. Focal uptake (odds ratio, 12.07; 95% confidence interval, 2.98-48.80; P < 0.01) and subjective highest suspicion level (odds ratio, 10.91; 95% confidence interval, 1.19-99.69; P = 0.03) correlated with true positivity. Using the receiver-operating-characteristic curve, optimal cutoffs for marrow TBR were 1.9 (area under the curve, 0.82) and 1.8 (area under the curve, 0.85) at early and delayed imaging, respectively. With these cutoffs, 15 of 17 malignant lesions were identified at both time points; however, fewer false-positive lesions were detected at the delayed time point (5/33) than at the early time point (11/33). Conclusion: True positivity of 18F-fluciclovine-targeted prostate biopsy in non-prostatectomy-treated patients correlates with focal uptake, TBR (blood pool and marrow), and subjective highest suspicion level. A marrow TBR of 1.9 at the early time point and 1.8 at the delayed time point had optimal discriminating capabilities. Despite the relatively low intraprostate positive predictive value (34.0%) with 18F-fluciclovine, application of these parameters to interpretative criteria may improve true positivity in the treated prostate.


Subject(s)
Carboxylic Acids , Cyclobutanes , Positron Emission Tomography Computed Tomography , Prostate/pathology , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Aged , Biological Transport , Biopsy , Carboxylic Acids/metabolism , Cyclobutanes/metabolism , Humans , Male , Prostate/diagnostic imaging , Prostatic Neoplasms/metabolism , ROC Curve , Recurrence
2.
J Urol ; 202(2): 413-421, 2019 08.
Article in English | MEDLINE | ID: mdl-30817240

ABSTRACT

PURPOSE: We assessed the feasibility and cancer detection rate of fluciclovine (18F) positron emission tomography-ultrasound fusion targeted biopsy vs standard template biopsy in the same patient with biochemical failure after nonsurgical therapy for prostate cancer. MATERIALS AND METHODS: A total of 21 patients with a mean ± SD prostate specific antigen of 7.4 ± 6.8 ng/ml and biochemical failure after nonoperative prostate cancer treatment underwent fluciclovine (18F) positron emission tomography-computerized tomography (mean 364.1 ± 37.7 MBq) and planning transrectal prostate ultrasound with 3-dimensional image reconstruction. Focal prostatic activity on positron emission tomography was delineated and co-registered with planning ultrasound. During the subsequent biopsy session computer generated 12-core template biopsies were performed and then fluciclovine defined targets were revealed and biopsied. Histological analysis of template and targeted cores were completed. RESULTS: Template biopsy was positive for malignancy in 6 of 21 patients (28.6%), including 10 of 124 regions and 11 of 246 cores, vs targeted biopsy in 10 of 21 (47.6%), including 17 of 50 regions and 40 of 125 cores. Five of 21 patients had positive findings on targeted biopsy only and 1 of 21 had positive findings on template biopsy only. An additional case was upgraded from Grade Group 2 to 3 on targeted biopsy. Extraprostatic disease was detected in 8 of 21 men (38.1%) with histological confirmation in all 3 who underwent lesion biopsy. CONCLUSIONS: Fluciclovine positron emission tomography real-time ultrasound fusion guidance for biopsy is feasible in patients with biochemical failure after nonsurgical therapy for prostate cancer. It identifies more recurrent prostate cancer using fewer cores compared with template biopsy in the same patient. Further study is required to determine in what manner targeted biopsy may augment template biopsy of recurrent prostate cancer.


Subject(s)
Carboxylic Acids , Cyclobutanes , Image-Guided Biopsy , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Positron-Emission Tomography , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Aged , Aged, 80 and over , Feasibility Studies , Humans , Male , Middle Aged , Positron-Emission Tomography/instrumentation , Positron-Emission Tomography/methods , Prospective Studies , Treatment Outcome , Ultrasonography/instrumentation
3.
Am J Clin Oncol ; 42(1): 36-41, 2019 01.
Article in English | MEDLINE | ID: mdl-29912804

ABSTRACT

PURPOSE: Radical cystectomy currently remains the standard of care for muscle-invasive bladder cancer. However, surgery can be associated with considerable morbidity and mortality, including the removal of the bladder. An alternative strategy is to preserve the bladder through concurrent chemoradiation following a maximal transurethral resection of the tumor. National protocols using a bladder-preservation approach have demonstrated disease-specific outcomes comparable to radical cystectomy in selected patients, but these results have not been replicated in previously reported population-based series. Here, we describe an outcomes analysis of patients with muscle-invasive bladder cancer treated with either radical surgery or bladder-preserving chemoradiation (BPCRT) for those patients meeting BPCRT criterion using the National Cancer Database (NCDB). MATERIALS AND METHODS: Using the NCDB, patients with American Joint Commission on Cancer clinical T2-3, N0, M0 urothelial carcinoma diagnosed between 2004 and 2013 were included for analysis. Only patients treated with definitive intent with either radical cystectomy or concurrent chemotherapy and radiation after a maximal transurethral tumor resection were included. Propensity-score matching was used. RESULTS: Among 8454 eligible patients, 7276 (86%) underwent radical cystectomy, and 1178 (14%) underwent BPCRT. Patients undergoing BPCRT were significantly older (median age, 77 vs. 68 y; P<0.001) and had higher Charlson-Deyo comorbidity scores (P=0.002). Using propensity-matched analysis, 1002 patients remained in each cohort, and there was no significant difference in survival found between the 2 cohorts (median overall survival, 2.7 vs. 3.0 y [P=0.20]; 4-year overall survival, 39.1% and 42.6% [P=0.15], for BPCRT and surgery, respectively). In addition, the hazard ratio (HR) of surgery versus BPCRT decreased over time, with an initial HR of 1.27 favoring BPCRT which decreased by a factor of 0.85 per year. CONCLUSIONS: From 2004 to 2013, ∼14% of patients from the NCDB who potentially met bladder-preservation criteria underwent the procedure. Our propensity-matched analysis is the only report of its kind to demonstrate similar survival outcomes with bladder preservation when patients are properly selected. This study is also the first to demonstrate a dynamic HR between radical surgery and BPCRT over time.


Subject(s)
Chemoradiotherapy/methods , Urinary Bladder Neoplasms/mortality , Urinary Bladder Neoplasms/surgery , Aged , Comorbidity , Cystectomy , Female , Humans , Kaplan-Meier Estimate , Male , Organ Sparing Treatments , Treatment Outcome , Urinary Bladder/surgery , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/therapy
4.
Article in English | MEDLINE | ID: mdl-30245541

ABSTRACT

Prostate segmentation in computed tomography (CT) images is useful for planning and guidance of the diagnostic and therapeutic procedures. However, the low soft-tissue contrast of CT images makes the manual prostate segmentation a time-consuming task with high inter-observer variation. We developed a semi-automatic, three-dimensional (3D) prostate segmentation algorithm using shape and texture analysis and have evaluated the method against manual reference segmentations. In a training data set we defined an inter-subject correspondence between surface points in the spherical coordinate system. We applied this correspondence to model the globular and smoothly curved shape of the prostate with 86, well-distributed surface points using a point distribution model that captures prostate shape variation. We also studied the local texture difference between prostate and non-prostate tissues close to the prostate surface. For segmentation, we used the learned shape and texture characteristics of the prostate in CT images and we used a set of user inputs for prostate localization. We trained our algorithm using 23 CT images and tested it on 10 images. We evaluated the results compared with those of two experts' manual reference segmentations using different error metrics. The average measured Dice similarity coefficient (DSC) and mean absolute distance (MAD) were 88 ± 2% and 1.9 ± 0.5 mm, respectively. The averaged inter-expert difference measured on the same dataset was 91 ± 4% (DSC) and 1.3 ± 0.6 mm (MAD). With no prior intra-patient information, the proposed algorithm showed a fast, robust and accurate performance for 3D CT segmentation.

5.
Eur J Radiol ; 102: 1-8, 2018 May.
Article in English | MEDLINE | ID: mdl-29685521

ABSTRACT

PURPOSE: To investigate the disease detection rate, diagnostic performance and interobserver agreement of fluciclovine (18F) PET-CT and multiparametric magnetic resonance imaging (mpMR) in recurrent prostate cancer. METHODS: Twenty-four patients with biochemical failure after non-prostatectomy definitive therapy, 16/24 of whom had undergone brachytherapy, underwent fluciclovine PET-CT and mpMR with interpretation by expert readers blinded to patient history, PSA and other imaging results. Reference standard was established via a multidisciplinary truth panel utilizing histology and clinical follow-up (22.9 ±â€¯10.5 months) and emphasizing biochemical control. The truth panel was blinded to investigative imaging results. Diagnostic performance and interobserver agreement (kappa) for the prostate and extraprostatic regions were calculated for each of 2 readers for PET-CT (P1 and P2) and 2 different readers for mpMR (M1 and M2). RESULTS: On a whole body basis, the detection rate for fluciclovine PET-CT was 94.7% (both readers), while it ranged from 31.6-36.8% for mpMR. Kappa for fluciclovine PET-CT was 0.90 in the prostate and 1.0 in the extraprostatic regions. For mpMR, kappa was 0.25 and 0.74, respectively. In the prostate, 22/24 patients met the reference standard with 13 malignant and 9 benign results. Sensitivity, specificity and positive predictive value (PPV) were 100.0%, 11.1% and 61.9%, respectively for both PET readers. For mpMR readers, values ranged from 15.4-38.5% for sensitivity, 55.6-77.8% for specificity and 50.0-55.6% for PPV. For extraprostatic disease determination, 18/24 patients met the reference standard. Sensitivity, specificity and PPV were 87.5%, 90.0% and 87.5%, respectively, for fluciclovine PET-CT, while for mpMR, sensitivity ranged from 50 to 75%, specificity 70-80% and PPV 57-75%. CONCLUSION: The disease detection rate for fluciclovine PET-CT in non-prostatectomy patients with biochemical failure was 94.7% versus 31.6-36.8% for mpMR. For extraprostatic disease detection, fluciclovine PET-CT had overall better diagnostic performance than mpMR. For the treated prostate, fluciclovine PET-CT had high sensitivity though low specificity for disease detection, while mpMR had higher specificity, though low sensitivity. Interobserver agreement was also higher with fluciclovine PET-CT compared with mpMR.


Subject(s)
Carboxylic Acids , Cyclobutanes , Magnetic Resonance Imaging/methods , Neoplasm Recurrence, Local/diagnosis , Positron Emission Tomography Computed Tomography/methods , Prostatic Neoplasms/diagnosis , Radiopharmaceuticals , Aged , Aged, 80 and over , Brachytherapy/statistics & numerical data , Humans , Magnetic Resonance Imaging/standards , Male , Middle Aged , Observer Variation , Positron Emission Tomography Computed Tomography/standards , Prospective Studies , Prostatic Neoplasms/radiotherapy , Reference Standards , Sensitivity and Specificity
6.
Urology ; 115: 39-44, 2018 May.
Article in English | MEDLINE | ID: mdl-29174940

ABSTRACT

OBJECTIVE: To provide an update on SpaceOAR System, a Food and Drug Administration-approved hydrogel indicated to create distance between the prostate and the rectum which has been studied in phase 2 and 3 clinical trials. Here, we review and summarize these clinical results including the safety of prostate-rectum spacer application technique, the implant quality and resulting rectal dose reduction, acute and long-term rectal, urinary, and sexual toxicity, as well as patient-reported outcomes. MATERIALS AND METHODS: A prospective, randomized patient-blinded clinical study was performed comparing image-guided intensity modulated prostate radiotherapy (79.2 Gy in 44 fractions) in men with or without prostate-rectum hydrogel spacer. Patients were followed up for 3 years, allowing assessment of long-term safety and efficacy. RESULTS: Spacer application was well tolerated with a 99% technical success rate. The mean additional space created between the prostate and the rectum was just over 1 cm, which allowed significant rectum and penile bulb radiation dose reduction, resulting in less acute pain, lower rates of late rectal toxicity, and improved bowel and urinary quality of life (QOL) scores from 6 months onward. Improvements in sexual QOL were also observed at 37 months in baseline-potent men, with 37.5% of control and 66.7% of spacer men capable of "erections sufficient for intercourse." CONCLUSION: Prostate-rectum hydrogel spacer application is a relatively safe technical procedure that is well tolerated and has a high technical success rate. Spacer application significantly reduces rectal radiation dose and results in long-term reductions in rectal toxicity, as well as improvements in bowel, urinary, and sexual QOL.


Subject(s)
Hydrogels/administration & dosage , Organs at Risk , Polyethylene Glycols/administration & dosage , Prostatic Neoplasms/radiotherapy , Rectum/radiation effects , Clinical Trials, Phase III as Topic , Humans , Male , Quality of Life , Radiotherapy/adverse effects , Radiotherapy/methods , Sexuality
7.
Clin Transl Imaging ; 5(1): 29-43, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28971090

ABSTRACT

PURPOSE: This paper provides a review on molecular imaging with positron emission tomography (PET) and magnetic resonance imaging (MRI) for prostate cancer detection and its applications in fusion targeted biopsy of the prostate. METHODS: Literature search was performed through the PubMed database using the keywords "prostate cancer", "MRI/ultrasound fusion", "molecular imaging", and "targeted biopsy". Estimates in autopsy studies indicate that 50% of men older than 50 years of age have prostate cancer. Systematic transrectal ultrasound (TRUS) guided prostate biopsy is considered the standard method for prostate cancer detection and has a significant sampling error and a low sensitivity. Molecular imaging technology and new biopsy approaches are emerging to improve the detection of prostate cancer. RESULTS: Molecular imaging with PET and MRI shows promising results in the early detection of prostate cancer. MRI/TRUS fusion targeted biopsy has become a new clinical standard for the diagnosis of prostate cancer. PET molecular image-directed, three-dimensional ultrasound-guided biopsy is a new technology that has great potential for improving prostate cancer detection rate and for distinguishing aggressive prostate cancer from indolent disease. CONCLUSION: Molecular imaging and fusion targeted biopsy are active research areas in prostate cancer research.

8.
Article in English | MEDLINE | ID: mdl-30220767

ABSTRACT

Automatic segmentation of the prostate on CT images has many applications in prostate cancer diagnosis and therapy. However, prostate CT image segmentation is challenging because of the low contrast of soft tissue on CT images. In this paper, we propose an automatic segmentation method by combining a deep learning method and multi-atlas refinement. First, instead of segmenting the whole image, we extract the region of interesting (ROI) to delete irrelevant regions. Then, we use the convolutional neural networks (CNN) to learn the deep features for distinguishing the prostate pixels from the non-prostate pixels in order to obtain the preliminary segmentation results. CNN can automatically learn the deep features adapting to the data, which are different from some handcrafted features. Finally, we select some similar atlases to refine the initial segmentation results. The proposed method has been evaluated on a dataset of 92 prostate CT images. Experimental results show that our method achieved a Dice similarity coefficient of 86.80% as compared to the manual segmentation. The deep learning based method can provide a useful tool for automatic segmentation of the prostate on CT images and thus can have a variety of clinical applications.

9.
Asian J Urol ; 4(4): 230-238, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29387555

ABSTRACT

OBJECTIVE: Several inflammatory markers have been studied as potential biomarkers in renal cell carcinoma (RCC), however few reports have analyzed their prognostic value in aggregate and in non-clear cell histologies. We hypothesize that a combination of specific inflammatory markers into an RCC Inflammatory Score (RISK) could serve as a rigorous prognostic indicator of overall survival (OS) in patients with clear cell and non-clear cell RCC. METHODS: Combination of preoperative C-reactive protein (CRP), albumin, erythrocyte sedimentation rate (ESR), corrected calcium, and aspartate transaminase to alanine transaminase (AST/ALT) ratio was used to develop RISK. RISK was developed using grid-search methodology, receiver-operating-characteristic (ROC) analysis, and sensitivity-specificity trade-off analysis. Prognostic value of RISK was analyzed using the Kaplan-Meier method and Cox proportional regression models. Predictive accuracy was compared with RISK to Size, Size, Grade, and Necrosis (SSIGN) score, University of California-LOS Angeles (UCLA) Integrated Staging System (UISS), and Leibovich Prognosis Score (LPS). RESULTS: Among 391 RCC patients treated with nephrectomy, area under the curve (AUC) for RISK was 0.783, which was comparable to SSIGN (AUC 0.776, p = 0.82) and UISS (AUC 0.809, p = 0.317). Among patients with localized disease, AUC for RISK and LPS was 0.742 and 0.706, respectively (p = 0.456). On multivariate analysis, we observed a step-wise statistically significant inverse relationship between increasing RISK group and OS (all p < 0.001). CONCLUSION: RISK is an independent and significant predictor of OS for patients treated with nephrectomy for clear cell and non-clear cell RCC, with accuracy comparable to other histopathological prognostic tools.

10.
J Nucl Med ; 58(3): 412-418, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27609792

ABSTRACT

The purpose of this study was to evaluate the role of the synthetic amino acid PET radiotracer 18F-fluciclovine in modifying the defined clinical and treatment-planning target volumes in postprostatectomy patients undergoing salvage radiotherapy and to evaluate the resulting dosimetric consequences to surrounding organs at risk. Methods: Ninety-six patients were enrolled in a randomized, prospective intention-to-treat clinical trial for potential salvage radiotherapy for recurrent prostate cancer after prostatectomy. The initial treatment plan was based on the results from conventional abdominopelvic CT and MRI. The 45 patients in the experimental arm also underwent abdominopelvic 18F-fluciclovine PET/CT, and the images were registered with the conventional images to determine whether the results would modify the initial treatment plan. The 51 patients in the control arm did not undergo 18F-fluciclovine PET/CT. For each patient, the clinical and treatment-planning target volumes that would have been treated before 18F-fluciclovine registration were compared with those after registration. For organs at risk (rectum, bladder, and penile bulb), the volumes receiving 40 Gy and 65 Gy before registration were compared with those after registration. Statistical comparisons were made using the paired t test. Acute genitourinary and gastrointestinal toxicity as defined by the Radiation Therapy Oncology Group was compared between the control and experimental arms using the χ2 test. Results: In 24 cases, radiotherapy was planned to a clinical target volume consisting of the prostate bed alone (CTV) (64.8-66.6 Gy). In 21 cases, radiotherapy was planned to a clinical target volume consisting of the pelvis (CTV1) (45.0 Gy) followed by a boost to the prostate bed (CTV2) (19.8-25.2 Gy). In each case, the respective treatment-planning target volume expansion (PTV, PTV1, or PTV2) was 0.8 cm (0.6 cm posterior). With the exception of PTV2, all postregistration volumes were significantly larger than the corresponding preregistration volumes. Analysis of the rectum, bladder, and penile bulb volumes receiving 40 Gy and 60 Gy demonstrated that only the penile bulb volumes were significantly higher after registration. No significant differences in acute genitourinary or gastrointestinal toxicity were observed. Conclusion: Including information from 18F-fluciclovine PET in the treatment-planning process led to significant differences in the defined target volume, with higher doses to the penile bulb but no significant differences in rectal or bladder dose or in acute genitourinary or gastrointestinal toxicity. Longer follow-up is needed to determine the impact of 18F-fluciclovine PET on cancer control and late toxicity endpoints.


Subject(s)
Carboxylic Acids , Cyclobutanes , Positron-Emission Tomography/methods , Prostatic Neoplasms/pathology , Prostatic Neoplasms/therapy , Radiotherapy, Image-Guided/methods , Salvage Therapy/methods , Humans , Male , Middle Aged , Pilot Projects , Prognosis , Prostatectomy , Prostatic Neoplasms/diagnostic imaging , Radiopharmaceuticals , Radiotherapy Dosage , Radiotherapy, Conformal/methods , Reproducibility of Results , Sensitivity and Specificity , Treatment Outcome , Tumor Burden
11.
J Urol ; 197(3 Pt 1): 676-683, 2017 03.
Article in English | MEDLINE | ID: mdl-27746282

ABSTRACT

PURPOSE: Sensitive detection of cancer foci in men experiencing biochemical recurrence following initial treatment of prostate cancer is of great clinical significance with a possible impact on subsequent treatment choice. We describe a multisite experience of the efficacy and safety of the positron emission tomography/computerized tomography agent fluciclovine (18F) after biochemical recurrence. MATERIALS AND METHODS: A total of 596 patients underwent fluciclovine (18F) positron emission tomography/computerized tomography at 4 clinical sites. Detection rate determinations were stratified by the baseline prostate specific antigen value. Diagnostic performance was assessed against a histological reference standard in 143 scans. RESULTS: The subject level fluciclovine (18F) positron emission tomography/computer tomography detection rate was 67.7% (403 of 595 scans). Positive findings were detected in the prostate/bed and pelvic lymph node regions in 38.7% (232 of 599) and 32.6% of scans (194 of 596), respectively. Metastatic involvement outside the pelvis was detected in 26.2% of scans (155 of 591). The subject level detection rate in patients in the lowest quartile for baseline prostate specific antigen (0.79 ng/ml or less) was 41.4% (53 of 128). Of these patients 13 had involvement in the prostate/bed only, 16 had pelvic lymph node involvement without distant disease and 24 had distant metastases. The positive predictive value of fluciclovine (18F) positron emission tomography/computerized tomography scanning for all sampled lesions was 62.2%, and it was 92.3% and 71.8% for extraprostatic and prostate/bed involvement, respectively. Fluciclovine (18F) was well tolerated and the safety profile was not altered following repeat administration. CONCLUSIONS: Fluciclovine (18F) is well tolerated and able to detect local and distant prostate cancer recurrence across a wide range of prostate specific antigen values.


Subject(s)
Carboxylic Acids , Cyclobutanes , Positron Emission Tomography Computed Tomography , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Neoplasm Staging , Predictive Value of Tests , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Retrospective Studies
12.
Clin Nucl Med ; 42(1): e22-e28, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27749412

ABSTRACT

PURPOSE: We explored the influence of FACBC (fluciclovine) PET/CT on the decision to offer radiotherapy and radiotherapy treatment field recommendations in postprostatectomy patients with recurrent prostate cancer. PATIENTS AND METHODS: After obtaining institutional review board approval and informed consent, 87 patients with detectable prostate-specific antigen (PSA) levels were recruited into a prospective clinical trial. After an initial provider-determined radiotherapy plan based on conventional imaging, 44 of 87 patients were randomized to additionally undergo fluciclovine PET/CT. Pre- and post-fluciclovine radiotherapy decisions were compared and changes were noted. Statistical significance of these decision changes was determined. RESULTS: Two of 44 patients in the experimental arm dropped out before fluciclovine scanning. Thirty-four (81.0%) of 42 had positive results on fluciclovine. Overall radiotherapy decision was changed in 17 (40.5%) of 42. Mean PSA, original Gleason score, and prostatectomy-PET interval did not differ significantly between patients with and without radiotherapy decision changes. Two (4.8%) of 42 had the decision for radiotherapy withdrawn due to positive extrapelvic findings. Radiotherapy field decision was changed in 15 (35.7%) of 42. Eleven (73.3%) of 15 had fields changed from prostate bed only to both prostate bed and pelvis, while 4 (26.7%) of 15 had fields changed from both prostate bed and pelvis to prostate bed only. Changes in overall radiotherapy decision and field were statistically significant (P < 0.0001). However, the change in the decision to offer radiotherapy or not was not statistically significant (P = 0.15). CONCLUSIONS: Fluciclovine PET/CT significantly changed radiotherapy management decisions in postprostatectomy patients with recurrent prostate cancer. Further work in determining differences in PSA-free survival is ongoing.


Subject(s)
Clinical Decision-Making/methods , Neoplasm Recurrence, Local/therapy , Prostatectomy , Prostatic Neoplasms/therapy , Radiotherapy/statistics & numerical data , Salvage Therapy/statistics & numerical data , Adult , Aged , Aged, 80 and over , Carboxylic Acids , Chronic Disease , Cyclobutanes , Disease Management , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/diagnostic imaging , Positron Emission Tomography Computed Tomography , Prospective Studies , Prostate-Specific Antigen , Prostatic Neoplasms/diagnostic imaging , Radiopharmaceuticals
13.
Proc SPIE Int Soc Opt Eng ; 97862016 Feb 27.
Article in English | MEDLINE | ID: mdl-27660383

ABSTRACT

This paper proposes a new semi-automatic segmentation method for the prostate on 3D transrectal ultrasound images (TRUS) by combining the region and classification information. We use a random walk algorithm to express the region information efficiently and flexibly because it can avoid segmentation leakage and shrinking bias. We further use the decision tree as the classifier to distinguish the prostate from the non-prostate tissue because of its fast speed and superior performance, especially for a binary classification problem. Our segmentation algorithm is initialized with the user roughly marking the prostate and non-prostate points on the mid-gland slice which are fitted into an ellipse for obtaining more points. Based on these fitted seed points, we run the random walk algorithm to segment the prostate on the mid-gland slice. The segmented contour and the information from the decision tree classification are combined to determine the initial seed points for the other slices. The random walk algorithm is then used to segment the prostate on the adjacent slice. We propagate the process until all slices are segmented. The segmentation method was tested in 32 3D transrectal ultrasound images. Manual segmentation by a radiologist serves as the gold standard for the validation. The experimental results show that the proposed method achieved a Dice similarity coefficient of 91.37±0.05%. The segmentation method can be applied to 3D ultrasound-guided prostate biopsy and other applications.

15.
Urology ; 96: 99-105, 2016 10.
Article in English | MEDLINE | ID: mdl-27431662

ABSTRACT

OBJECTIVE: To evaluate the relationship between the Onodera Prognostic Nutritional Index (OPNI) and overall survival, as well as recurrence-free survival, in clear cell renal cell carcinoma (ccRCC) patients following nephrectomy. MATERIALS AND METHODS: Three hundred forty-one patients who underwent nephrectomy for ccRCC were analyzed. The optimum OPNI cutoff score of 44.7 was determined by receiver operating characteristic analysis and patients were placed in either the low or high OPNI group, with OPNI values of ≤44.7 and ≥44.8, respectively. Kaplan-Meier analysis was performed to evaluate the univariate impact of the OPNI groups on overall survival and recurrence-free survival. OPNI's association with overall survival and recurrence-free survival, with adjustments for other patient and tumor qualities, was assessed with univariate and multivariate Cox regression analysis. RESULTS: Median (95% CI) overall survival times for the low and high OPNI groups were 21.1 months and 37.9 months, respectively. OPNI was determined to be an independent prognostic factor in multivariate analysis, and after controlling for patient and tumor characteristics, the low OPNI group experienced a 1.67-fold (hazard ratio: 1.67, 95% confidence interval: 1.05-2.68) increased risk of overall mortality. CONCLUSION: Preoperative OPNI is a valuable independent prognostic indicator of overall survival and recurrence-free survival in patients with ccRCC following nephrectomy.


Subject(s)
Carcinoma, Renal Cell/mortality , Carcinoma, Renal Cell/surgery , Kidney Neoplasms/mortality , Kidney Neoplasms/surgery , Nephrectomy , Nutrition Assessment , Female , Humans , Male , Middle Aged , Prognosis , Survival Rate
16.
Eur J Nucl Med Mol Imaging ; 43(10): 1773-83, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27091135

ABSTRACT

PURPOSE: To compare the diagnostic performance of the synthetic amino acid analogue PET radiotracer anti-3-[(18)F]FACBC (fluciclovine) with that of CT in the detection of recurrent prostate carcinoma. METHODS: This was a retrospective analysis of 53 bone scan-negative patients with suspected recurrent prostate carcinoma who underwent fluciclovine PET/CT and routine clinical CT within 90 days of each other. The correlation between imaging findings and histology and clinical follow-up was evaluated. Positivity rates and diagnostic performance were calculated for fluciclovine PET/CT and CT. RESULTS: Of 53 fluciclovine PET/CT and 53 CT examinations, 41 (77.4 %) and 10 (18.9 %), respectively, had positive findings for recurrent disease. Positivity rates were higher with fluciclovine PET/CT than with CT at all prostate-specific antigen (PSA) levels, PSA doubling times and original Gleason scores. In the prostate/bed, fluciclovine PET/CT was true-positive in 31 and CT was true-positive in 4 of 51 patients who met the reference standard. In extraprostatic regions, fluciclovine PET/CT was true-positive in 12 and CT was true-positive in 3 of 41 patients who met the reference standard. Of the 43 index lesions used to prove positivity, 42 (97.7 %) had histological proof. In 51 patients with sufficient follow-up to calculate diagnostic performance in the prostate/bed, fluciclovine PET/CT demonstrated a sensitivity of 88.6 %, a specificity of 56.3 %, an accuracy of 78.4 %, a positive predictive value (PPV) of 81.6 %, and a negative predictive value (NPV) of 69.2 %; the respective values for CT were 11.4 %, 87.5 %, 35.3 %, 66.7 % and 31.1 %. In 41 patients with sufficient follow-up to calculate diagnostic performance in extraprostatic regions, fluciclovine PET/CT demonstrated a sensitivity of 46.2 %, a specificity of 100 %, an accuracy of 65.9 %, a PPV of 100 %, and an NPV of 51.7 %; the respective values for CT were 11.5 %, 100 %, 43.9 %, 100 % and 39.5 %. CONCLUSION: The diagnostic performance of fluciclovine PET/CT in recurrent prostate cancer is superior to that of CT and fluciclovine PET/CT provides better delineation of prostatic from extraprostatic recurrence.


Subject(s)
Bone Neoplasms/diagnostic imaging , Bone Neoplasms/secondary , Carboxylic Acids , Cyclobutanes , Neoplasm Recurrence, Local/diagnostic imaging , Positron Emission Tomography Computed Tomography/methods , Prostatic Neoplasms/diagnostic imaging , Aged , Humans , Image Enhancement/methods , Male , Middle Aged , Neoplasm Recurrence, Local/prevention & control , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Radiopharmaceuticals , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed/methods
17.
Asian J Urol ; 3(1): 20-25, 2016 Jan.
Article in English | MEDLINE | ID: mdl-29264158

ABSTRACT

OBJECTIVE: Inflammatory serum markers have proven to be a powerful predictive tool of patient prognosis in cancer treatment for a wide variety of solid organ malignancies, predominantly in the context of localized disease. In this study we evaluated the preoperative neutrophil-to-lymphocyte ratio (NLR) as a predictive tool in patients with metastatic clear cell renal cell carcinoma (RCC). METHODS: Sixty-four patients with metastatic clear cell RCC undergoing nephrectomy were selected. Only patients with preoperative NLR were included for survival analysis. Patients were categorized into high and low NLR score determined by plotting the NLR ROC curve. Multivariable analysis was performed. RESULTS: Median age was 60.8 years (38.2-81.2). Median follow-up time was 8.1 months (0.1-106.3). Fuhrman grade distribution was: 2 (3.1%) grade 1, 6 (9.4%) grade 2, 24 (37.5%) grade 3 and 32 (50.0%) grade 4. Median NLR score was 3.5 (1.4-31.0). NLR ≥ 4 was associated with decreased overall survival compared to NLR < 4 (p = 0.017). Multivariable survival analysis showed NLR ≥ 4 as an independent predictor of survival (Hazard ratio (HR) 2.41, 95%CI 1.05-5.50, p = 0.03). CONCLUSION: Elevated preoperative NLR is associated with poor prognosis in patients with metastatic kidney cancer. Preoperative NLR is a useful tool, which can predict prognosis, stratify patients for postoperative surveillance, and help guide decisions for therapy.

18.
Can J Urol ; 22(3): 7783-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26068625

ABSTRACT

INTRODUCTION: Sarcomatoid urothelial carcinoma is a dedifferentiated biphasic tumor that exhibits morphological and/or immunohistochemical evidence of epithelial and mesenchymal differentiation. In this series, we analyzed the clinicopathologic features of this rare variant of urothelial carcinoma. MATERIALS AND METHODS: A search was made through our surgical pathology files and consultation files of the senior author for cases of sarcomatoid urothelial carcinoma of the bladder from 2005-2014. All the slides were retrieved and re-reviewed, and clinical data was also obtained including follow up. RESULTS: Thirty-seven cases of sarcomatoid urothelial carcinoma of the bladder were identified. Mean patient age was 71 years (range: 51 to 88 years). Twenty-six of 37 (70%) patients were male and 11/37 (30%) patients were female. Twenty-five cases were from cystectomy/cystoprostatectomy specimens, 8 cases from transurethral resection of bladder tumor specimens and 4 cases were from biopsy specimens. The mean tumor size was 5 cm (range: 1.4 cm to 13.0 cm). Four of 37 (10%) cases had focal heterologous components; 1 case with both chondroid and osteoid, 2 cases with chondroid and 1 case rhabdoid elements. Twenty-one of 37 (56%) patients died within a year of presentation. CONCLUSIONS: Sarcomatoid urothelial carcinoma of the bladder is more prevalent in males, with the mean age of 71 years in our series. Smoking is an important risk factor. Sarcomatoid urothelial carcinoma is an aggressive variant of urothelial carcinoma which commonly presents at an advanced stage, and over 50% of patients in our series died of disease within 1 year of presentation.


Subject(s)
Carcinoma, Transitional Cell/pathology , Carcinosarcoma/pathology , Urinary Bladder Neoplasms/pathology , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies , Survival Rate , Tumor Burden
19.
Mol Imaging Biol ; 17(2): 277-83, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25281411

ABSTRACT

PURPOSE: The aim of this study is to examine the reproducibility of anti-1-amino-3-[(18)F]fluorocyclobutane-1-carboxylic acid (anti-3-[(18)F]FACBC) quantitative measurements in key background structures and untreated malignant lesions. PROCEDURES: Retrospective review of 14 patients who underwent follow-up anti-3-[(18)F]FACBC positron emission tomography-X-ray computed tomography (PET-CT) for prostate carcinoma recurrence. Standard uptake values (SUV) were measured in both original and follow-up scans in key background structures and untreated malignant lesions. Absolute and percent mean difference in SUV between scans and interclass correlation coefficients (ICC) were also computed. RESULTS: Mean (±SD, range) scan interval was 17.4 months (±7.1, 4-29). %Mean difference in SUVmean was <20 % in background structures with low absolute differences. ICCs were >0.6 except for early-phase blood pool (ICC = 0.4). SUVmax in malignant lesions without interim therapy increased or remained stable over time. CONCLUSIONS: Despite variable time interval between scans, FACBC PET-CT demonstrates acceptable reproducibility in key background structures. Untreated malignant lesions showed stable or increased uptake over time. A formal test-retest study is planned.


Subject(s)
Carboxylic Acids/pharmacokinetics , Cyclobutanes/pharmacokinetics , Positron-Emission Tomography , Prostatic Neoplasms/diagnostic imaging , Tomography, X-Ray Computed , Aged , Follow-Up Studies , Humans , Male , Middle Aged , Reproducibility of Results
20.
Indian J Urol ; 30(1): 33-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24497679

ABSTRACT

PURPOSE: The modified Glasgow prognostic Score (mGPS) incorporates C-reactive protein and albumin as a clinically useful marker of tumor behavior. The ability of the mGPS to predict metastasis in localized renal cell carcinoma (RCC) remains unknown in an external validation cohort. PATIENTS AND METHODS: Patients with clinically localized clear cell RCC were followed for 1 year post-operatively. Metastases were identified radiologically. Patients were categorized by mGPS score as low-risk (mGPS = 0 points), intermediate-risk (mGPS = 1 point) and high-risk (mGPS = 2 points). Univariate, Kaplan-Meier and multivariate Cox regression analyses examined Recurrence -free survival (RFS) across patient and disease characteristics. RESULTS: Of the 129 patients in this study, 23.3% developed metastases. Of low, intermediate and high risk patients, 10.1%, 38.9% and 89.9% recurred during the study. After accounting for various patient and tumor characteristics in multivariate analysis including stage and grade, only mGPS was significantly associated with RFS. Compared with low-risk patients, intermediate- and high-risk patients experienced a 4-fold (hazard ratios [HR]: 4.035, 95% confidence interval [CI]: 1.312-12.415, P = 0.015) and 7-fold (HR: 7.012, 95% CI: 2.126-23.123 P < 0.001) risk of metastasis, respectively. CONCLUSIONS: mGPS is a robust predictor of metastasis following potentially curative nephrectomy for localized RCC. Clinicians may consider mGPS as an adjunct to identify high-risk patients for possible enrollment into clinical trials or for patient counseling.

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