68Ga-PSMA PET/CT Urachus Metastases in Recurrent Prostate Cancer With Very Low PSA Level

International audiencePeritoneal carcinomatosis in prostate cancer is extremely rare and has been described in only few cases with high PSA level, androgen deprivation , or in symptomatic patients. To date, 2 cases of 68 Ga-PSMA PET positive peritoneal metastases have been reported. We report a case of urachus metastases showed on 68 Ga-PSMA PET/CT performed for biochemical recurrence with a very low PSA level at 0.50 ng/mL

Advantages of systematic trunk SPECT/CT to planar bone scan (PBS) in more than 300 patients with breast or prostate cancer

International audiencePropose:The aim of our study was to evaluate the potential benefit of a systematic trunk SPECT/CT associated with a Planar Bone Scan (PBS) in breast cancer (BC) and prostate cancer (PCa) patients at initial staging or recurrence.Results:In 328 patients, sensitivities and specificities were between 74.4-93% and 78.8-97.5% for PBS and 97.7-100% and 96.8-98.6% for SPECT/CT respectively. PBS was considered equivocal for 67 compared to only 6 patients for trunk SPECT/CT. Regardless of "optimistic" or "pessimistic" analysis of equivocal trunk SPECT/CT lesions, the trunk SPECT/CT was almost perfect, allowing to rely on this result for excluding metastatic disease which was corroborated by ROC curve analysis. The trunk SPECT/CT allowed downstaging for 62 patients (19%) and upstaging for 11 patients.Materials and Methods:PBS and a trunk SPECT/CT were systematically performed in all patients. Independent review of PBS and trunk SPECT/CT was performed for each patient and an abnormality interpretative score (Sc) with 3 levels was built: Sc 1: metastatic or probably metastatic pattern, Sc 2: equivocal pattern, Sc 3: benign or probably benign pattern or no abnormality. The bone pattern status was defined by at least 1 year follow-up. The clinical impact was evaluated in terms of down and upstaging in patient analysis.Conclusions:Trunk SPECT/CT improves the performance of PBS in BC and PCa assessments and results in improvements in both the detection performance of bone metastases as well as a better characterization of equivocal lesions

Haute Couture or Ready-To-Wear? Tailored Pelvic Radiotherapy for Prostate Cancer Based on Individualized Sentinel Lymph Node Detection

International audienceProstate cancer (PCa) pelvic radiotherapy fields are defined by guidelines that do not consider individual variations in lymphatic drainage. We examined the feasibility of personalized sentinel lymph node (SLN)-based pelvic irradiation in PCa. Among a SLN study of 202 patients, we retrospectively selected 57 patients with a high risk of lymph node involvement. Each single SLN clinical target volume (CTV) was individually segmented and pelvic CTVs were contoured according to Radiation Therapy Oncology Group (RTOG) guidelines. We simulated a radiotherapy plan delivering 46 Gy and calculated the dose received by each SLN. Among a total of 332 abdominal SLNs, 305 pelvic SLNs (beyond the aortic bifurcation) were contoured (mean 5.4/patient). Based on standard guidelines, CTV missed 67 SLNs (22%), mostly at the common iliac level (40 SLNs). The mean distance between iliac vessels and the SLN was 11mm, and despite a 15mm margin around the iliac vessels, 9% of SLNs were not encompassed by the CTV. Moreover, 42 SLNs (63%) did not receive 95% of the prescribed dose. Despite a consensus on contouring guidelines, a significant proportion of SLNs were not included in the pelvic CTV and did not receive the prescribed dose. A tailored approach based on individual SLN detection would avoid underdosing pelvic lymph nodes that potentially contain tumor cells

Preliminary results of 68Ga-PSMA PET/CT prospective study in prostate cancer occult recurrence patients : diagnostic performance and impact on therapeutic decision-making

International audienceIntroduction: The aim of this prospective study was to investigate the impact of 68Ga-PSMA-11 PET/CT on current management of prostate cancer patients with occult biochemical recurrence (BCR). Subjects & Methods: 130 hormone-naïve occult BCR (PSA from 0.05 to 1.6 ng/mL) patients were enrolled in a prospective study (NCT03443609). All patients received a radical treatment (prostatectomy +/- radiotherapy) which allowed to an undetectable PSA level. Before PSMA PET/CT, patients were screened by conventional imaging as mpMRI and bone scan (+ trunk SPECT/ CT) and enrolled only if conventional imaging was doubtful or normal. PET images were recorded 1 and 2 hours after injection of 150 MBq of tracer and images interpreted by 2 nuclear physicians. Referring patient physician completed 2 questionnaires to assess PSMA PET imaging influence on therapeutic strategy: one prior and one after PSMA PET/CT indicating treatment plan without and with PSMA PET/CT information respectively. Six months after the end of treatment, a PSA assay was requested to evaluate therapeutic efficacy. Results: Currently, we have complete data analysis of the first 52 patients. After pre-screening, 7 patients were excluded due to positive MRI (5 pts) or bone scan (2 pts). The median time from radical prostatectomy or radiotherapy to BCR was 4.92y (0.6-15.46). Thirty-eight among the 52 patients (73%) had a positive PSMA PET/CT. Ninety-four lesions were detected, 53/94 in lymph nodes (56.4%) predominantly dispatched on pelvic area (75.5%), 25/94 in bone (26.6%) (mostly on axial skeleton) and 12/94 into prostate bed (12.7%). Detection rates were 56 %, 87 % and 74% for patients with PSA value ranging from 0.05 to 0.3, 0.3 to 0.6 and 0.6 to 1.6 ng/ml respectively. Thanks to PSMA PET/CT, therapeutic management changed in 35/52 patients (67.3%). PSMA-positive patients had undetectable PSA level after stereotaxic radiotherapy or focal surgery based on PSMA results in 30.7% (16/52). In this particular hormone naïve patient population, Rauscher’s nomogram (1) was not validate, may be due a too small population. Conclusion: Preliminary results of this prospective study showed, in more than half of patients, a major impact of PSMA PET/CT on treatment management allowing them to benefit very early from focal therapy with the great result for 30% of them of PSA complete response. Reference: (1) Rauscher I., et al: doi:10.1016/j.eururo.2018.01.00

68Ga‐PSMA‐11 PET‐CT study in prostate cancer patients with biochemical recurrence and non‐contributive 18F‐Choline PET‐CT: Impact on therapeutic decision‐making and biomarker changes

International audienceBACKGROUND:In this retrospective study, we investigated the impact of 68 Ga-PSMA-11 PET-CT (PSMA PET-CT) upon the treatment plan and therapeutic response obtained for Prostate Cancer (PCa) patients presenting an occult biochemical recurrence.METHODS:Forty-two patients with previously negative or doubtful 18F-Choline (FCH) were enrolled. PET images were recorded 1 h after injection of tracer. Only a few months after treatment ended, a PSA assay was requested to evaluate the therapeutic efficacy of the treatment based on PSMA results.RESULTS:PSMA-positive lesions were detected in 34/42 (80.9%) patients. Detection rates were 85.7% and 89.3% for serum PSA levels lower than 2 ng/mL, and >2 ng/mL, respectively. One hundred seventy-three lesions were detected: 132/173 in lymph nodes (76.3%), 22/173 as metastatic sites (bone or lung) (12.7%), and 19/173 in the prostate bed (10.9%). As a result of the PSMA PET-CT, therapeutic management changed in 31/42 patients (73.8%). With a follow-up of 4.9 ± 2.27 months, 32/42 (76.2%) PSA assays after treatment guided by PSMA PET-CT were collected. For 37.5% (12/32) of patients, the serum PSA level was lower than 0.2 ng/mL and a PSA decrease of over 50% in 8 (25.0%) other patients were obtained.CONCLUSION:Performing a PSMA PET-CT when FCH PET-CT was doubtful or negative allows the recurrence localization in more 80% of patients and this had a major clinical impact, as it resulted in treatment change in more than 70% of patients as well as a significant decrease in PSA levels in more than 60% of them

Prognostic Impact of Pretherapeutic FDG-PET in Localized Anal Cancer

International audienceDue to the heterogeneity of tumour mass segmentation methods and lack of consensus, our study evaluated the prognostic value of pretherapeutic positron emission tomography with fluorodeoxyglucose (FDG-PET) metabolic parameters using different segmentation methods in patients with localized anal squamous cell carcinoma (SCC). Eighty-one patients with FDG-PET before radiochemotherapy were retrospectively analyzed. Semiquantitative data were measured with three fixed thresholds (35%, 41% and 50% of Maximum Standardized Uptake Value (SUVmax)) and four segmentation methods based on iterative approaches (Black, Adaptive, Nestle and Fitting). Metabolic volumes of primary anal tumour (P-MTV) and total tumour load (T-MTV: P-MTV+ lymph node MTV) were calculated. The primary endpoint was event-free survival (EFS). Seven multivariate models were created to compare FDG-PET tumour volumes prognostic impact. For all segmentation thresholds, PET metabolic volume parameters were independent prognostic factor and T-MTV variable was consistently better associated with EFS than P-MTV. Patient's sex was an independent variable and significantly correlated with EFS. With fixed threshold segmentation methods, 35% of SUVmax threshold seemed better correlated with EFS and the best cutoff for discrimination between a low and high risk of event occurrence was 40 cm 3. Determination of T-MTV by FDG-PET using fixed threshold segmentation is useful for predicting EFS for primary anal SCC. If these data are confirmed in larger studies, FDG-PET could contribute to individualized patient therapies