Early PSA decline after starting second-generation hormone therapy in the post-docetaxel setting predicts cancer-specific survival in metastatic castrate-resistant prostate cancer.

BACKGROUND: The objective of this study was to evaluate the prognostic value of early PSA decline following initiation of second-generation hormone therapy (2nd HT), namely abiraterone acetate or enzalutamide, in patients with taxane-refractory metastatic castrate-resistant prostate cancer (mCRPC) and evaluate utility of this metric in informing intensified surveillance/imaging protocols. METHODS: We retrospectively identified 75 mCRPC patients treated with 2nd HT following docetaxel failure (defined as PSA rise and radiographic progression). Patients were categorized patients into two cohorts based on the first PSA within 3 months after initiation of therapy: PSA reduction ≥50% (Group A) and PSA reduction <50% (Group B). The primary endpoint was cancer-specific mortality (CSM). The secondary endpoint was radiographic disease progression (rDP) on 2nd HT. In univariate and multivariate analyses, we investigated factors associated with rPD and CSM. RESULTS: We included 75 patients (52 in Group A, 23 in Group B) in the analytic cohort. Baseline clinico-demographic characteristics, including median age, primary Gleason score risk group, median pre-treatment PSA, disease burden, site of metastases, and pre-treatment ECOG score were not statistically different between the two groups. Median follow up time was 30 months and the median time to radiographic disease progression was 28.1 and 12.5 months (p = 0.002) in cohorts A and B, respectively. On univariate and multivariate analyses, both PSA reduction ≥50% and volume of metastatic disease were significantly associated with a decreased risk of radiographic disease progression (HR 0.41, 95% CI 0.21-0.80, p = 0.0113) as well as a decreased risk of cancer-specific mortality (HR 0.29, 95% CI 0.09-0.87, p = 0.0325). CONCLUSION: PSA reduction ≥50% within 3 months of starting 2nd HT was associated with significantly improved radiographic disease progression-free survival and 3-year cancer-specific mortality. This suggests using PSA 50%-decline metric in surveillance patients with on 2nd HT and identifies patients who require further evaluation with imaging.

Relationship between histopathological features of non-infectious aortitis and the results of pre-operative 18F-FDG-PET/CT: a retrospective study of 16 patients.

OBJECTIVES: To describe the characteristics of 18F-fluorodeoxyglucose positron-emission tomography/computed-tomography (18FDG-PET/CT) findings before surgery in patients with active, histologically confirmed aortitis, and to correlate the degree of arterial wall inflammation with PETVAS score. METHODS: This was a multiple-centre retrospective study including cases with histologically proven active, non-infectious aortitis who had a 18FDG-PET/CT performed within one year before surgery for aneurysm repair. PETVAS score was determined by radiologists blinded to the pathology findings. Cardiovascular pathologists reviewed aortic tissue samples and graded the degree of inflammation in the vessel wall. RESULTS: Sixteen patients were included (8 giant cell arteritis, 4 clinically isolated aortitis, 2 Takayasu's arteritis, 1 relapsing polychondritis, and 1 rheumatoid arthritis). In 5/16 (31%) patients, 18FDG-PET/CT did not detect the presence of aortic inflammation; two of whom were being treated with glucocorticoids at the time of procedure. Ascending thoracic and abdominal aorta had the highest FDG uptake among the affected territories. Patients without active aortitis on 18FDG-PET/CT were significantly older (p=0.027), had a lower PETVAS score (p=0.007), and had a lower degree of adventitial inflammation (p=0.035). In contrast, there was no difference between 18FDG-PET/CT active and inactive aortitis patients as regards the timing between PET/CT and surgery, serum CRP level (during 18FDG-PET/CT) and, FDG uptake per study site. CONCLUSIONS: In histologically proved aortitis, 18FDG-PET/CT before surgery did not detect vascular inflammation in 31% patients, and PETVAS score correlated with the degree of adventitial histopathologic inflammation.

Radiographic paradoxical response in metastatic castrate-resistant prostate cancer (mCRPC) managed with new generation anti-androgens: a retrospective analysis.

BACKGROUND: Prostatic specific antigen (PSA) has well-recognized limitations as a marker for treatment response and disease progression. Post hoc analysis of the PREVAIL trial reported 24.5% of chemotherapy naïve metastatic castration-resistant prostate cancer (mCRPC) patients on enzalutamide had radiographic progression on conventional imaging with nonrising PSA. In this study, we sought to study the discordance of imaging with PSA kinetics in mCRPC patients on second generation anti-androgens (SGA) post-chemotherapy using combined conventional imaging, and new generation imaging in the form of C-11 choline positron emission tomography/computed tomography (C[11] choline PET/CT) scan. METHODS: We retrospectively reviewed the medical records of 123 patients with mCRPC treated with SGA (Abiraterone or Enzalutamide) after docetaxel between 2016 and 2019. Patients underwent PSA testing, and C[11] choline PET/CT scan at baseline level before starting treatment with SGA, then every 3-6 months as part of their follow up evaluation. Loss of response to SGA was defined by increase in corrected maximum standardized uptake value (SUVmax) of pretreatment lesions on C-11 Choline PET/CT, and/or development of new lesions. Suspicious new lesions were confirmed by biopsy and/or conventional imaging. RESULTS: We identified 123 mCRPC patients who received SGA (Abiraterone, n = 106; Enzalutamide, n = 17) after docetaxel. Median duration of therapy was 13.9 months (interquartile range: 8.75-21.14). Approximately 43% (n = 53) of subjects in this study exhibited an increase in choline avidity while on SGA. Of this group, 60.4% of patients experienced a parallel rise in PSA (Group-A), whereas 39.6% displayed a paradoxical response (PR) (Group-B), defined as increased choline avidity combined with stable or down-trending PSA. Median PSA at time of increase in choline avidity was 3.1 ng/ml for Group-A, and 1.3 ng/ml for Group-B (p = 0.0176). Median SUVmax was similar in both groups (4.9 for Group-A, 4.6 for Group-B; p = 0.6072). The median time for increase in choline avidity was 9.5 versus 3.9 months for Group-A versus Group-B, respectively (Log-Rank = 0.0063). CONCLUSION: Nearly 40% of mCRPC patients placed on SGA post docetaxel chemotherapy will exhibit paradoxical responses to therapy, therefore, warranting close follow up with imaging. C-11 choline PET/CT imaging is a useful tool that can help in early predication of disease progression or treatment failure.

Prognostic role of 11C-choline PET/CT scan in patients with metastatic castrate resistant prostate cancer undergoing primary docetaxel chemotherapy.

BACKGROUND: We sought to assess the prognostic utility of 11C-choline positron emission tomography/computed tomography (PET/CT) in patients with metastatic castrate resistant prostate cancer (mCRPC) undergoing primary docetaxel chemotherapy. METHODS: We performed a single institution retrospective analysis of 77 mCRPC patients who were treated with 6 cycles of docetaxel chemotherapy, and who also underwent 11C-choline PET/CT scans at baseline (before chemotherapy), mid-course (after 3 cycles), and posttherapy (after 6 cycles). We evaluated treatment response based on percent change in blood pool-corrected maximum standardized uptake value (SUVmax) of the target lesion on PET/CT, as well as percent change in serum prostate specific antigen (PSA). Logistic regression analysis was used to identify factors associated with complete treatment response. Progression free survival (PFS) analysis was performed using log-rank test and shown on Kaplan-Meier plot. RESULTS: Percent change in blood pool-corrected SUVmax on mid-course scan was a significant predictor of complete response (odds ratio [OR]: 0.98, 95% confidence interval [CI]: 0.96-0.99, p = .0003), whereas percent change in PSA was not (OR: 0.99, 95% CI: 0.99-1.01, p = .6025). 57 of 77 patients (74%) achieved ≥20% reduction in blood pool-corrected SUVmax on mid-course; these patients were 3.6 times more likely to achieve complete response after full 6 cycles of docetaxel chemotherapy, compared to patients with <20% reduction in blood pool-corrected SUVmax (OR: 3.56, 95% CI: 1.04-16.52, p = .0420). Median PFS in the complete response group was 35.1 months (95% CI: 26.0-52.7 months), compared to 9.4 months (95% CI: 6.9-13.0 months) in the incomplete response group (p = .0005). CONCLUSIONS: Our study showed that mid-course and posttherapy 11C-choline PET/CT evaluation for mCRPC patients undergoing primary docetaxel chemotherapy can predict full course treatment response and PFS, respectively. 11C-choline PET/CT imaging may provide valuable prognostic information to guide treatment choices for patients with mCRPC.

Phase II Evaluation of Stereotactic Ablative Radiotherapy (SABR) and Immunity in 11C-Choline-PET/CT-Identified Oligometastatic Castration-Resistant Prostate Cancer.

PURPOSE: Outcomes for resistant metastatic castration-resistant prostate cancer (CRPC) are poor. Stereotactic ablative radiotherapy (SABR) induces antitumor immunity in clinical and preclinical studies, but immunologic biomarkers are lacking. PATIENTS AND METHODS: Eighty-nine patients with oligometastatic CRPC were identified by 11C-Choline-PET (Choline-PET) from August 2016 to December 2019 and treated with SABR. Prespecified coprimary endpoints were 2-year overall survival (OS) and PSA progression. Secondary endpoints included 2-year SABR-treated local failure and 6-month adverse events. Correlative studies included peripheral blood T-cell subpopulations before and after SABR. RESULTS: 128 lesions in 89 patients were included in this analysis. Median OS was 29.3 months, and 1- and 2-year OS were 96% and 80%, respectively. PSA PFS was 40% at 1 year and 21% at 2 years. Local PFS was 84.4% and 75.3% at 1 and 2 years, respectively, and no grade ≥3 AEs were observed. Baseline high levels of tumor-reactive T cells (TTR; CD8+CD11ahigh) predicted superior local, PSA, and distant PFS. Baseline high levels of effector memory T cells (TEM; CCR7-CD45RA-) were associated with improved PSA PFS. An increase in TTR at day 14 from baseline was associated with superior OS. CONCLUSIONS: This is the first comprehensive effector T-cell immunophenotype analysis in a phase II trial before and after SABR in CRPC. Results are favorable and support the incorporation of immune-based markers in the design of future randomized trials in patients with oligometastatic CRPC treated with SABR.

Detection of distal ureteral stones in pregnancy using transvaginal ultrasound.

AIMS: To determine the performance of transvaginal ultrasound for the visualization of distal ureteral stones in pregnant patients with renal colic and to evaluate the diagnostic value of secondary findings suggestive of obstructing ureteral stone disease. METHODS: We retrospectively identified 129 pregnant patients with a total of 142 encounters with both abdominal and transvaginal ultrasound. Ultrasound images for each patient were reviewed recording the presence of stone with location, hydronephrosis, resistive indices (RI), and status of the ureteral jets. Patients were subcategorized into two groups based on the visualization of distal ureteral stone. RESULTS: The transvaginal technique identified 94% (N = 16/17) of sonographically detected stones in the distal ureter/urethra, while the transabdominal technique identified 29% (N = 5/17). The combined imaging for initial assessment of renal colic in pregnancy demonstrated a sensitivity of 89%, specificity 100%, and negative predictive value (NPV) of 98%. The frequency of hydronephrosis was statistically greater in the visualized stone group (94% vs 51%). Mean RI was identical in both groups however the delta RI was significantly elevated in those patients with distal ureteral stones with a mean delta RI value of 0.05. The rate of absence of ureteral jets was not statistically significant. CONCLUSION: The present data would suggest a utility of transvaginal ultrasound for the evaluation of the pregnant patient with 94% of distal stones being detected transvaginal versus 29% transabdominally. Additionally, there was significantly increased hydronephrosis and elevated RIs in patients with distal ureteral stones.

Stroke detection with 3 different PET tracers.

Stroke is a common cause of patient morbidity and mortality, being the fifth leading cause of death in the United States. Positron emission tomography (PET) is a proven tool for oncology patients, and may have utility in patients with stroke. We demonstrate findings of stroke incidentally detected on oncologic PET/CTs using 18F-FDG, 11C-Choline, and 68Ga-DOTATATE radiotracers. Specifically, focal 11C-Choline or 68Ga-DOTATATE uptakes localized in areas of MRI confirmed ischemia, and paradoxically increased 18F-FDG activity was visualized surrounding a region of hemorrhage, in different patients. These cases demonstrate that PET may have utility in evaluating patients with stroke based on flow dynamics, metabolic activity, and receptor expression.

Arterial involvement in Erdheim-Chester disease: A retrospective cohort study.

Erdheim-Chester disease (ECD) is a rare histiocytosis of the "L" (Langerhans) group with multisystem involvement that can affect the large and medium-sized arteries mimicking vasculitis. Aortic involvement is common but the frequency and outcome of aortic branch vessel abnormalities are less well described.Patients with ECD were retrospectively identified. Images containing information of arterial involvement within 6 months of diagnosis were considered baseline and compared to last follow-up studies. Two physicians independently reviewed the studies to evaluate for presence of abnormalities attributable to ECD. Age and sex-adjusted logistic regression models were used to examine associations between patient characteristics and vessel involvement at baseline.Among a cohort of 64 patients with ECD, 63 had baseline imaging of vascular structures. ECD involvement of at least 1 segment of the aorta was observed in 56%. Abnormalities were also observed in aortic arch branches (26%), visceral branch arteries (40%), iliofemoral arteries (31%), coronary (5%), and pulmonary (3%) arteries. Perinephric fibrosis was strongly associated with the identification of abnormalities in the thoracic aorta (OR 4.92 [1.54, 15.75]; P = .007), abdominal aorta (OR 7.57 [2.28, 25.07]; P = .001) and visceral branch arteries (OR 6.05 [1.52, 24.03]; P = .01) but not pelvic/lower extremity arteries. Complete normalization of arterial abnormalities at follow-up was only observed in 9% or less of arterial segments involved at baseline.Aortic and aortic branch vessel abnormalities are frequently observed in patients with ECD and are often asymptomatic. Partial and/or complete resolution of arterial findings is uncommon.