Search results for "prostate carcinoma"

Prospective Image Quality and Lesion Assessment in the Setting of MR-Guided Radiation Therapy of Prostate Cancer on an MR-Linac at 1.5 T: A Compariso…

2021

The objective of this study is to conduct a qualitative and a quantitative image quality and lesion evaluation in patients undergoing MR-guided radiation therapy (MRgRT) for prostate cancer on a hybrid magnetic resonance imaging and linear accelerator system (MR-Linac or MRL) at 1.5 Tesla. This prospective study was approved by the institutional review board. A total of 13 consecutive patients with biopsy-confirmed prostate cancer and an indication for MRgRT were included. Prior to radiation therapy, each patient underwent an MR-examination on an MRL and on a standard MRI scanner at 3 Tesla (MRI3T). Three readers (two radiologists and a radiation oncologist) conducted an independent qualita…

Do we truly see what we think we see? The role of cognitive bias in pathological interpretation

2008

In the histomorphological grading of prostate carcinoma, pathologists have regularly assigned comparable scores for the architectural Gleason and the now-obsolete nuclear World Health Organization (WHO) grading systems. Although both systems demonstrate good correspondence between grade and survival, they are based on fundamentally different biological criteria. We tested the hypothesis that this apparent concurrence between the two grading systems originates from an interpretation bias in the minds of diagnostic pathologists, rather than reflecting a biological reality. Three pathologists graded 178 prostatectomy specimens, assigning Gleason and WHO scores on glass slides and on digital im…

Diagnostic Performance of 68Ga-PSMA-11 Positron-emission-tomography/Computed-tomography in a Large Cohort of Patients with Biochemical Recurrence of …

2020

Gallium-68 (Ga) prostate-specific-membrane-antigen positron-emission-tomography/computed-tomography is a highly promising method for imaging primary and recurrent prostate cancer. These dual-modality imaging technologies enable whole-body functional and anatomical evaluation in a single session. This study investigated the performance of Ga-prostate-specific-membrane-antigen-11 positron-emission-tomography/computed-tomography for detecting prostate carcinoma in patients with rising prostate-specific-antigen after primary therapy. Six hundred sixty (660) patients with biochemical recurrence referred for positron-emission-tomography/computed-tomography with Ga-prostate-specific-membrane-antig…

The effect of overall treatment time in radiotherapy for localized prostate carcinoma

1991

Optimization of Labeling PSMAHBED with Ethanol-Postprocessed 68Ga and Its Quality Control Systems

2017

Radiolabeling of the prostate-specific membrane antigen (PSMA) inhibitor Glu-NH-CO-NH-Lys(Ahx) using the 68Ga chelator HBED-CC (PSMAHBED) allows imaging of prostate cancer lesions because of high expression of PSMA in prostate carcinoma cells and in bone metastases and lymph nodes related to the disease. The aim of this work was to optimize labeling of 68Ga-PSMAHBED using the efficient cation-exchange postprocessing of 68Ga as well as the development of a thin-layer chromatography (TLC)-based quality control system. Methods: Labeling was optimized for online ethanol-postprocessed 68Ga eluate investigating various parameters, such as buffer molarity (0.1-1 M), temperature (25°C-90°C), tracer…

Clinical Significance of Measuring Prostate-Specific Antigen

2009

The incidence of prostate-specific antigen (PSA) monitoring has increased in recent years. However, interpretation of the results is often ambiguous and leads to uncertainty for both the patient and the treating physician. Advantages and disadvantages of measuring PSA and possibilities for improved interpretation using the variable PSA quotient are given. After reading this article, readers should be able to better interpret PSA values and assess the risk of prostate carcinoma using PSA quotient. In addition, errors associated with PSA and PSA quotient measurement are compared and discussed. Chemistry exam 20907 questions and corresponding answer form are located after this CE Update on pag…

PSA reduction (after antibiotics) permits to avoid or postpone prostate biopsy in selected patients

2007

Microscopic foci of prostatitis may induce prostate-specific antigen (PSA) increase. PSA reduction after antibiotics might identify those patients in whom biopsy can be avoided. Ninety-nine patients received ciprofloxacin for 3 weeks, of whom 59 showed PSA reduction. Histology detected small foci of prostatitis in 65% of cases. Carcinoma was found in 40 and 20.3% of patients with unchanged or decreased PSA, respectively (P=0.03). No cancer was detected if PSA decreased below 4 ng/ml or more than 70%. Biopsy can be postponed, with a low risk of missing a cancer, if PSA decreases more than 70% or below 4 ng/ml.

The Impact of 68Ga-PSMA PET/CT and PET/MRI on the Management of Prostate Cancer.

2018

Prostate-specific membrane antigen (PSMA) is a transmembrane protein with significantly increased expression in the cells and metastases of prostate carcinoma (CaP). PSMA-expression correlates with higher serum levels of prostate-specific antigen (PSA) and a higher Gleason score (GS). This finding has led to the development of novel imaging modalities such as 68Ga-/18F-labeled PSMA positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance imaging (PET/MRI). This article reviews the literature pertaining to various new imaging technologies for the management of CaP. PSMA positron emission tomography/computed tomography appears to be an exce…

Salvage Therapy With Oral Metronomic Cyclophosphamide and Methotrexate for Castration refractory Metastatic Adenocarcinoma of the Prostate Resistant …

2011

Objective To investigate the activity and toxicity of metronomic chemotherapy with low-dose oral cyclophosphamide (CTX) and methotrexate (MTX) in patients with metastatic CRPC that progresses after docetaxel. Patients with castration-resistant prostate cancer (CRPC) that progresses after docetaxel may benefit from receiving further chemotherapy. Methods Patients were treated with CTX 50 mg/d p.o. plus MTX 2.4 mg p.o. twice per week without rest periods. All patients received simultaneous luteinizing hormone-releasing hormone analogue. Prostate-specific antigen (PSA) response was defined as a 50% reduction on 2 evaluations at least 4 weeks apart. Objective response was measured according to …

Prediction of Normal Organ Absorbed Doses for [177Lu]Lu-PSMA-617 Using [44Sc]Sc-PSMA-617 Pharmacokinetics in Patients With Metastatic Castration Resi…

2018

In vivo pharmacokinetic analysis of [Sc]Sc-PSMA-617 was used to determine the normal organ-absorbed doses that may result from therapeutic activity of [Lu]Lu-PSMA-617 and to predict the maximum permissible activity of [Lu]Lu-PSMA-617 for patients with metastatic castration-resistant prostate carcinoma. Methods Pharmacokinetics of [Sc]Sc-PSMA-617 was evaluated in 5 patients with metastatic castration-resistant prostate carcinoma using dynamic PET/CT, followed by 3 static PET/CT acquisitions and blood sample collection over 19.5 hours, as well as urine sample collection at 2 time points. Total activity measured in source organs by PET imaging, as well as counts per milliliter measured in bloo…