Imaging Biomarkers in Prostate Stereotactic Body Radiotherapy: A Review and Clinical Trial Protocol (original) (raw)
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International Journal of Radiation Oncology*Biology*Physics, 2015
The use of positron emission tomography (PET) with radiolabeled choline analogues has shown promise in detection of prostate cancer (CaP) recurrence after definitive local therapy. Magnetic Resonance Imaging (MRI) is increasingly used for CaP staging and has superior soft-tissue resolution and options for multiparametric and functional imaging. The simultaneous use of PET and MRI has been enabled by a new generation of hybrid PET/MRI scanners. We designed a pilot study examining the feasibility of hybrid PET/MRI using 18F-FCH for evaluating men with suspected CaP recurrence who were being considered for local salvage therapies after initial radical prostatectomy (RP) or radical radiation therapy (RT). Materials/Methods: Seventeen men (out of a planned 20) with suspected CaP recurrence and negative conventional restaging (bone scan and computed tomography) have been accrued: 10 post-RP and 7 post-RT. PET/ MRI were acquired as follows: T2W MRI and PET of the pelvis with bodyarray coil followed by whole-body PET/MRI using 3 to 5 bed positions (from skull vertex to proximal femora) with simultaneous PET and MRI followed by MR only imaging of the pelvis. A consensus report of the PET/MRI was generated by joint read by a radiologist and nuclear medicine physician. Questionnaires were completed by the referring physicians prior to and after imaging reports to investigate the clinical impact of PET/MRI. Results: Median prostate-specific antigen (PSA) of the 10 post-RP men at the time of PET/MRI imaging was 0.575 (range 0.19-7.77). Seven of 10 (70%) had an initial Gleason Score (GS) of 7, and 2 of 10 (20%) had GS of 8-9. One did not have a GS available due to previous hormonal effects. Four of 10 post-RP men had lesions detected on PET/MRI. Lesions were primarily in regional or distant nodal regions and most had concordant PET and MRI findings. In 50% (2 of 4) with positive PET/MRI findings and 33% (2 of 6) with negative findings there was a change in the degree of certainty as to suspected site of recurrence. Change in management occurred in 100% (4 of 4) with positive PET/MRI and 0 of 6 with negative PET/MRI. Preliminary analysis for 4 of 7 post-RT men has been performed. Two men had lesions detected on PET/MRI; 1 isolated to the prostate and 1 in regional nodes. Two had negative PET/MRI. Results for the completed radiation therapy cohort (planned nZ10) will also be presented. Conclusion: 18F-FCH PET/MRI shows promise for men with suspected CaP recurrence following RP or RT. PET/MRI findings had impact on clinical certainty of sites of recurrence and management.
World Journal of Urology, 2021
Purpose To evaluate outcomes for men with biochemically recurrent prostate cancer who were selected for transponder-guided salvage radiotherapy (SRT) to the prostate bed alone by 68Ga-labelled prostate-specific membrane antigen positron emission tomography (68Ga-PSMA-PET). Methods This is a single-arm, prospective study of men with a prostate-specific antigen (PSA) level rising to 0.1–2.5 ng/mL following radical prostatectomy. Patients were staged with 68Ga-PSMA-PET and those with a negative finding, or a positive finding localised to the prostate bed, continued to SRT only to the prostate bed alone with real-time target-tracking using electromagnetic transponders. The primary endpoint was freedom from biochemical relapse (FFBR, PSA > 0.2 ng/mL from the post-radiotherapy nadir). Secondary endpoints were time to biochemical relapse, toxicity and patient-reported quality of life (QoL). Results Ninety-two patients (median PSA of 0.18 ng/ml, IQR 0.12–0.36), were screened with 68Ga-PS...
Cancers, 2021
Technical advances in radiotherapy (RT) treatment planning and delivery have substantially changed RT concepts for primary prostate cancer (PCa) by (i) enabling a reduction of treatment time, and by (ii) enabling safe delivery of high RT doses. Several studies proposed a dose–response relationship for patients with primary PCa and especially in patients with high-risk features, as dose escalation leads to improved tumor control. In parallel to the improvements in RT techniques, diagnostic imaging techniques like multiparametric magnetic resonance imaging (mpMRI) and positron-emission tomography targeting prostate-specific-membrane antigen (PSMA-PET) evolved and enable an accurate depiction of the intraprostatic tumor mass for the first time. The HypoFocal-SBRT study combines ultra-hypofractionated RT/stereotactic body RT, with focal RT dose escalation on intraprostatic tumor sides by applying state of the art diagnostic imaging and most modern RT concepts. This novel strategy will b...
International Journal of Radiation Oncology Biology Physics, 2009
The radiobiology of prostate cancer favors a hypofractionated dose regimen. We report results of a prospective Phase II clinical trial of stereotactic body radiotherapy (SBRT) for localized prostate cancer.Forty-one low-risk prostate cancer patients with 6 months' minimum follow-up received 36.25 Gy in five fractions of 7.25 Gy with image-guided SBRT alone using the CyberKnife. The early (<3 months) and late (>6 months) urinary and rectal toxicities were assessed using validated quality of life questionnaires (International Prostate Symptom Score, Expanded Prostate Cancer Index Composite) and the Radiation Therapy Oncology Group (RTOG) toxicity criteria. Patterns of prostate-specific antigen (PSA) response are analyzed.The median follow-up was 33 months. There were no RTOG Grade 4 acute or late rectal/urinary complications. There were 2 patients with RTOG Grade 3 late urinary toxicity and none with RTOG Grade 3 rectal complications. A reduced rate of severe rectal toxicities was observed with every-other-day vs. 5 consecutive days treatment regimen (0% vs. 38%, p = 0.0035). A benign PSA bounce (median, 0.4 ng/mL) was observed in 12 patients (29%) occurring at 18 months (median) after treatment. At last follow-up, no patient has had a PSA failure regardless of biochemical failure definition. Of 32 patients with 12 months minimum follow-up, 25 patients (78%) achieved a PSA nadir ≤0.4 ng/mL. A PSA decline to progressively lower nadirs up to 3 years after treatment was observed.The early and late toxicity profile and PSA response for prostate SBRT are highly encouraging. Continued accrual and follow-up will be necessary to confirm durable biochemical control rates and low toxicity profiles.
Purpose: This study aims to evaluate the association of the maximum standardized uptake value (SUVmax) in positron-emission tomography targeting prostate-specific-membrane-antigen (PSMA-PET) prior to savage radiotherapy (sRT) on biochemical recurrence free survival (BRFS) in a large multicenter cohort. Methods: Patients who underwent 68Ga-PSMA11-PET prior to sRT were enrolled in four high-volume centers in this retrospective multicenter study. Only patients with PET-positive local recurrence (LR) and/or nodal recurrence (NR) within the pelvis were included. Patients were treated with intensity-modulated-sRT to the prostatic fossa and elective lymphatics in case of nodal disease. Dose escalation was delivered to PET-positive LR and NR. Androgen deprivation therapy was administered at the discretion of the treating physician. LR and NR were manually delineated using and SUVmax was extracted for LR and NR. Cox-regression was performed to analyze the impact of clinical parameters and th...
Biomedicines
To investigate the role of 68 Ga-PSMA-11 PET/CT in guiding retreatment stereotactic body radiation therapy (SBRT) in prostate cancer (PCa) patients in biochemical recurrence (BCR) after salvage radiotherapy (S-RT). (2) Methods: We retrospectively evaluated PCa patients previously treated with S-RT on the prostate bed and with proven serum prostate antigen (PSA) failure after S-RT. In all patients (pts), 68 Ga-PSMA-11 PET/CT was positive in the prostate bed only and guided retreatment SBRT. All retreatments were performed by applying the same radiotherapy protocol (median dose of 18 Gy/3 fractions; IQR 18-21 Gy). The median follow-up was 27 months (range 4-35 months). (3) Results: 38 consecutive patients were considered in this analysis. The overall median PSA level before RT was 1.10 ng/mL (IQR 0.82-2.59). PSA decreased at 3 and 6 months after treatment, with a median value of 0.60 ng/mL (IQR 0.31-0.96; p < 0.001) and 0.51 ng/mL (IQR 0.29-1.17; p < 0.001), respectively. Overall, biochemical recurrence-free survival (b-RFS) was 15.0 months (95% CI 13-23). Grade-1 toxicity was reported in 31.6% of patients (12/38). (4) Conclusion: These results confirm that 68 Ga-PSMA-11-PET/CT is able to identify the site of recurrence in patients who have failed S-RT, thus supporting the use of metastases-directed radiotherapy as a safe and effective treatment.
International braz j urol
To the editor, Prostate cancer (PC) has a highly variable clinic. It can remain for an extended period of time without any findings, as well as shows an aggressive course. Early diagnosis is very important. The most important diagnostic methods used in the PC are digital rectal examination, transrectal ultrasonography and prostate specific antigen (PSA) values. The exact diagnosis is made by histopathology (1). The correct staging of the PC is very important as it directly affects the treatment decision and patient management. Currently, staging tests are not recommended since the risk of metastasis is low in patients with low risk compared to D'Amico risk classification. It is recommended that patients in the middle-high risk group be performed by abdominal computer tomography (CT) or magnetic resonance imaging (MRI) with bone scintigraphy for staging (2-4). Since the 1980s, MRI has been used in the evaluation of the prostate gland and its surrounding structures among radiological diagnostic methods. It was originally used for staging in patients with PC diagnosis, and for determining invasion and lymph node metastases. Conventional MRI examinations (especially T2-weighted examinations) are the basic method for detecting PC, but they have high sensitivity but low specificity (2). In recent years, new software and techniques in MRI technique have made progress in anatomical, functional and physiological evaluation. Thus, the evaluation has increased sensitivity and specificity. In addition to high-resolution T2A examinations, dynamic, diffusion and MRI spectroscopies have been added to the diagnosis of PC. The MRI technique performed by adding at least two functional MRIs to the T2A sequences is called Multiparametric MRI (Mp-MRI). This method is the most commonly used technique for prostate imaging today. It is especially recommended to use MRI device with 3 Tesla main magnet power in imaging. Compared to 1.5T tesla devices, the signal-to-noise ratio, temporal and spatial resolution are higher in 3T devices. Biopsies can be taken from the lesion described in the light of Mp-MRI, and this reduces false negative rates (4-6). One of the most important benefits of Mp-MRI is its extraprostatic extension and local recurrence. Because the extension outside the capsule and the seminal vesicle involvement counted in the extraprostatic extension criterion are independent pathological criteria that increase the risk of local recurrence, progression and death. The probability of local recurrence in these cases considered high risk is 40-50% (6, 7). According to the meta-analysis of 5681 cases by de Rooij et al; in extracapsular invasion, MRI sensitivity and specificity were found to be 57% and 91%, respectively (2). In a study by Pokorny et al. they compared transrectal ultrasound guided biopsy and MP-MRI guided biopsy. They found that the MP-MRI examination reduced the biopsy requirement by 51%. They also reported that the MP-MRI examination reduced the clinical significance of low prostate cancer by 89.4% and increased the detection of medium / high risk prostate cancer by 17.7%. (3). In a review, it is stated that Mp-MRI is found to be highly specific and highly sensitive in detecting local recurrences and in the diagnosis of
The role of radiomics in prostate cancer radiotherapy
Strahlentherapie und Onkologie, 2020
"Radiomics", as it refers to the extraction and analysis of large number of advanced quantitative radiological features from medical images using high throughput methods, is perfectly suited as an engine of effectively sifting through the multiple series of prostate images from before, during, and following radiotherapy (RT). Multiparametric (mp) MRI, planning CT and cone beam CT (CBCT), routinely acquired throughout the RT and radiomics pipeline, are developed for extraction of thousands of variables. Radiomics data are in a format that is amicable for building descriptive and predictive models relating image features to diagnostic, prognostic or predictive information. The prediction of Gleason Score, the histop cancer grade, has been the mainstay of the radiomic efforts in prostate cancer. While Gleason Score (GS) is still the best predictor for treatment outcome, there are other novel applications of quantitative imaging that are tailored to RT. In this review, we summarize the radiomics efforts and discuss several promising concepts such as delta-radiomics and radiogenomics for utilizing image features for assessment of the aggressiveness of prostate cancer and its outcome. We also discuss opportunities for quantitative imaging with the advance of the instrumentation of MRI-guided therapies.
68Ga-PSMA PET/CT in early relapsed prostate cancer patients after radical therapy
Scientific Reports
Biochemical recurrence (BCR) of prostate cancer (PCa) occurs in about 25% of patients treated with radical prostatectomy (RP) and up to 45% in patients who receive external beam radiotherapy (RT). Early diagnosis of PCa recurrence is of high importance for successful salvage therapy. The aim of the present study is to analyze the efficacy of 68 Ga-PSMA PET/CT in detecting the presence of local and/or systemic disease in patients with a history of PCa who have BCR. A total of 52 PCa patients with BCR referred for 68 Ga-PSMA PET/CT were recruited from the American University of Beirut Medical Center between November 2017 and December 2019. We compared the performance of PSMA PET/CT to the results and clinical factors based on follow up: PSA, PSA kinetics, primary treatment, and Gleason score. The relationship between the PET/CT findings and clinical indicators of disease were assessed by univariate and multivariate logistic regression. From a total of 52 patients, 34 (65.4%) had posit...