Differences in Distribution and Detection Rate of the [68Ga]Ga-PSMA Ligands PSMA-617, -I&T and -11—Inter-Individual Comparison in Patients with Biochemical Relapse of Prostate Cancer

The biochemical relapse of prostate cancer is diagnostically challenging but of high clinical impact for subsequent patient treatment. PET/CT with radiolabeled PSMA ligands outperforms conventional diagnostic methods in the detection of tumor recurrence. Several radiopharmaceuticals were and are available for use. The aim of this study was to investigate whether the routinely applied [68Ga]Ga-PSMA ligands PSMA-617, -I&T and -11 (HBED-CC) differ in physiological and pathological distribution, or in tumor detection rate. A retrospective evaluation of 190 patients (39 patients received PSMA-617, 68 patients PSMA-I&T and 83 patients PSMA-11) showed significant differences in tracer accumulation within all organs examined. The low retention within the compartments blood pool, bone and muscle tissue is a theoretical advantage of PSMA-11. Evaluation of tumor lesion uptake and detection rate did not reveal superiority of one of the three radiopharmaceuticals, neither in the whole population, nor in particularly challenging subgroups like patients with very low PSA levels. We conclude that all three [68Ga]Ga-PSMA ligands are equally feasible in this clinically important scenario, and may replace each other in case of unavailability or production restrictions.

Clinical Value of Serum Cancer Antigen 19-9 as a Tumor Screening Marker among Healthy Individuals

Background: Serum tumor markers are convenient, non-invasive, acceptable to patients and play an important role as an ancillary tumor diagnostic tool. CA 19-9 has become a common tumor marker, specific for digestive system tumors. The study was carried out to determine the value of CA 19-9 as a tumor screening marker among healthy individuals. Materials and Methods: This study had been carried in Dhaka Medical college Hospital from January 2016 to January 2018. The serum CA 19-9 level was detected using a microsome luminescence method. Individuals with high CA 19-9 levels underwent further examination, including routine fecal testing, thoracic and abdominal computed tomography (CT) scan, gastroscopy, and colonoscopy. These individuals had regular follow-up examinations. Results: Over a 3-year period, the serum CA19-9 levels of 960 healthy individuals were estimated. The CA 19-9 level of 15 individuals was positive (positive rate: 1.56%), including 7 men (7/699; 1.001%) and 8 women (8/261; 3.06%). There was a significant difference between males and females (p<0.01), The overall tumor detection rate was 0.72% (7/960) including 6/699 men (0.85%) and 1/261 women (0.38%). Conclusion: Therefore, elevated CA 19-9 level can be used to assist in the diagnosis malignancy. J MEDICINE JUL 2019; 20 (2) : 92-94

Efficacy of i-Scan Imaging for the Detection and Diagnosis of Early Gastric Carcinomas

We determined comparative efficacy of i-Scan for detection and diagnosis of gastric cancer. Ten patients diagnosed with early gastric cancer based on histopathological findings were analyzed. White light and i-Scan moving images recorded from these patients in twin mode were separated into white light and i-Scan. Twelve endoscopists (three different skill levels) blinded to patient information evaluated the images. Correlation between demarcation accuracy and lesion brightness on still images was investigated. No significant differences were found in diagnostic accuracy between white light and i-Scan moving images for tumor detection rate (91.7% versus 90.8%,P=0.777). Diagnostic accuracy of tumor size was comparable between novice and experienced endoscopists for i-Scan moving images (65.7% versus 71.1%,P=0.528), whereas it was significantly lower for white light moving images (41.2% versus 79.5%,P=0.019). Tumor demarcation accuracy was significantly better with white light than i-Scan still images (71.0% versus 65.8%,P=0.033). Correlations between demarcation accuracy and brightness reached highs of 0.75 for white light and 0.89 for i-Scan imaging. Efficacy of i-Scan over that of white light imaging for detecting and diagnosing gastric cancer was not shown; however, the diagnostic capability of i-Scan can be improved if imaging conditions are optimized.

Critical evaluation of MRI-targeted TRUS-guided transperineal fusion biopsy for detection of prostate cancer.

e16063 Background: Precise staging of prostate cancer (PC) is essential for individualized treatment decisions. However, the majority of transrectal biopsies are negative for prostate cancer or show imprecise results. Additionally, the rate of upgrading in Gleason scores between biopsy and prostatectomy specimen is around 30-40%. MRI/TRUS fusion has shown encouraging results for detecting clinically significant prostate cancer. Methods: 412 consecutive patients with suspicion of PC were prospectively included in our database. The median age of patients was 65 years (range 42-84). Mean PSA level was 9.56 ng/ml (± 7.9ng/ml, SD). 55% of men had previous TRUS-guided biopsies, 45% underwent primary biopsy. Imaging data and biopsy results were analyzed and a self-designed questionnaire was send to all men regarding further clinical history and adverse effects of the biopsy. Results: In 236 of 412 (57.3%) biopsy samples showed PC. 71.6% of biopsy proven PC were clinically significant (D’Amico criteria). On multiparametric (mp)-MRI, 120 men were reported as highly suspicious for PC and in these tumor detection rate was 83.3% (100/120). In patients without cancer-suspicious MRI-lesions, 31,8% (42/132) men were diagnosed with significant disease (Table 1). Regarding adverse effects, 152 patients (49%) reported hematuria after biopsy. 9 patients (2%) needed temporary catheterization after biopsy due to prostate swelling. In three patients (0.7%) febrile urinary tract infection occurred after biopsy. Major limitation is the limited follow-up of 12-months of biopsy-negative patients. Conclusions: MRI-targeted TRUS-guided transperineal fusion biopsy provides high detection rates of clinically significant tumors. mp-MRI still has its limitations, and therefore systematic biopsies should currently not be omitted. The morbidity of the transperineal saturation approach is reasonable and mainly self-limiting. [Table: see text]