Management Impact of Metachronous Oligometastatic Disease Identified on 18F-Fluciclovine (Axumin™) PET/CT in Biochemically Recurrent Prostate Cancer.

PURPOSE: We assessed the incidence rate and management impact of oligometastatic disease detected on 18F-fluciclovine (Axumin™) PET/CT in men with first biochemical recurrence (BCR) of prostate cancer (PCA) after definitive primary therapy. METHODS AND MATERIALS: We retrospectively reviewed our clinical database for men with PCA who underwent 18F-fluciclovine PET/CT for imaging evaluation of BCR with negative or equivocal findings on conventional imaging. We included patients with up to and including 5 metastases (oligometastases) regardless of imaging evidence for local recurrence in the treated prostate bed. We examined the association between mean serum prostate specific antigen (PSA) levels with the number of oligometastases (non-parametric ANOVA) and between patients with or without local recurrence (Student t-test). The management impact of oligometastatic disease was tabulated. RESULTS: We identified 21 patients with oligometastases upon first BCR (PSA 0.2-56.8 ng/mL) out of 89 eligible patients. There was a significant difference (p = 0.04) in the mean PSA levels between patients with local recurrence (n = 12) and those without local recurrence (n = 9). In the subgroup of analysis of patients without local recurrence, there was no significant association between mean PSA level and number of oligometastases (p = 0.83). Distribution of oligometastases included 66.7% isolated nodal disease and 33.3% bone only. Twelve (57.1%) patients had change in management to include change in ADT, salvage therapy, or both. Treatment change was initiated in 62.5%, 28.6%, 66.7%, 100%, and 100% of patients with 1, 2, 3, 4, and 5 oligometastatic lesions, respectively. CONCLUSION: The incidence rate of oligometastatic disease in men with first BCR of PCA undergoing 18F-fluciclovine PET/CT for imaging evaluation of BCR was 23.6% in our eligible patient population. There was no significant association between serum PSA level and the number of oligometastases. Treatment management was affected in 57.1% of patients with oligometastases.

COVID-19 pandemic revisited: lessons the radiology community has learned a year later.

For more than 1 year, COVID-19 pandemic has impacted every aspect of our lives. This paper reviews the major challenges that the radiology community faced over the past year and the impact the pandemic had on the radiology practice, radiologist-in-training education, and radiology research. The lessons learned from COVID-19 pandemic can help the radiology community to be prepared for future outbreaks and new pandemics, preserve good habits, enhance cancer screening programs, and adapt to the changes in radiology education and scientific meetings.

Management Impact of 68Ga-DOTATATE PET/CT in Neuroendocrine Tumors.

PURPOSE: The goal of our retrospective single tertiary academic medical center investigation was to examine the added diagnostic value and clinical impact of 68Ga-DOTATATE PET/CT in the therapeutic management of patients with neuroendocrine tumors (NETs). METHODS: Imaging database was queried for all "PET-DOTATATE" examinations performed at our tertiary care academic institution using MONTAGE™. The patient's clinical history and recent prior imaging were reviewed. The additional diagnostic value and clinical management impact of 68Ga-DOTATATE were assessed through retrospective chart review. RESULTS: A total of 81 68Ga-DOTATATE PET/CT scans in 74 patients were found, and 11 patients were excluded from analysis as they had no prior imaging available for comparison, with resultant analysis cohort of 63 patients. Six patients had 2 or more 68Ga-DOTATATE PET/CT examinations. The most common primary diagnosis was undifferentiated NET (63.5%), followed by carcinoid (27.0%), paraganglioma (4.8%), insulinoma (3.2%), and pheochromocytoma (1.6%). The primary sites of disease from the most to the least common were the pancreas (36.5%), small bowel (22.2%), unknown primary (15.9%), lung (6.3%), large bowel (6.3%), and mesentery (4.8%), and other locations accounted for 7.9%. In patients who had prior imaging available for comparison, there were new lesions identified on 68Ga-DOTATATE PET/CT in 21 patients (33.3%) that were not identified on other prior imaging modalities. Of these patients, 5 underwent subsequent MRI and 1 had a repeat 68Ga-DOTATATE PET/CT to further characterize new lesions seen. Moreover, 15 patients (23.8%) had a change in treatment plan, including altering medical therapy in 9 patients, change in planned extent of surgical management in 5 patients, and cancelation of a planned primary tumor resection in 1 patient with metastatic disease. CONCLUSION: Our retrospective cohort demonstrated that 68Ga-DOTATATE PET/CT improves lesion detection over conventional imaging in 33.3% and impacts the therapeutic management in 23.8% of patients with NET.

Comparative prognostic implication of treatment response assessments in mCRPC: PERCIST 1.0, RECIST 1.1, and PSA response criteria.

Accurate appraisal of treatment response in metastatic castrate-resistant prostate cancer (mCRPC) is challenging in view of remarkable tumor heterogeneity and the available choices among many established and novel therapeutic approaches. The purpose of this single-center prospective study was to evaluate the comparative prognostic utility of PERCIST 1.0 in predicting overall survival (OS) in patients with mCRPC compared to RECIST 1.1 and prostate-specific antigen (PSA)-based treatment response assessments. Methods: Patients with mCRPC were prospectively enrolled if they were beginning systemic medical therapy or transitioning to new systemic therapy after not responding to a prior treatment. All patients underwent a baseline 18F-fluorodeoxyglucose (FDG) positron emission tomography/ computed tomography (PET/CT) prior to the initiation of treatment and again 4 months after the start of therapy. Patients' responses to treatment at 4 months compared to baseline were evaluated with RECIST 1.1, PERCIST 1.0 and PSA response criteria. The associations between patients' response categories and OS were evaluated. OS was defined as the duration in time between the date of baseline PET/CT to death from any cause. Patients with different response status were compared with logrank tests. Survival probabilities were calculated using the Kaplan-Meier method. Results: Patients with progressive disease by PSA response criteria at 4 months demonstrated significantly shorter OS (24-month OS probability: 18% ± 11%) compared to patients with stable disease, SD, (44% ± 19%, p=0.03) and complete response, CR, or partial response, PR, (53% ± 11%, p=0.03). RECIST 1.1 response criteria demonstrated a similar trend in OS, however no statistically significant differences were noted between patients with PD (25% ± 15%) compared to SD/non-CR, non-PD (54% ± 13%) and CR/PR (54% ± 14%) (p=0.13). PERCIST 1.0 criteria demonstrated significant differences in OS between responders, CMR/PMR (56% ± 12%), compared to SMD (38% ± 17%, p=0.03) and PMD (21% ± 10%, p=0.01). Patients with progressive disease by both PERICST 1.0 and PSA response criteria demonstrated significantly worse OS (24-month OS: 0%, 12-month OS: 31% ± 14%) compared to patients with progressive disease by either response criteria. Conclusion: PERCIST 1.0 may provide significant prognostic information for patients with mCRPC undergoing systemic chemotherapy, particularly when incorporated with PSA treatment response criteria.

Treatment Response Assessment of Skeletal Metastases in Prostate Cancer with 18F-NaF PET/CT.

PURPOSE: To determine the utility of 18F-sodium fluoride positron emission tomography-computed tomography (18F-NaF PET/CT) in the imaging assessment of therapy response in men with osseous-only metastatic prostate cancer. METHODS: In this Institutional Review Board-approved single institution retrospective investigation, we evaluated 21 18F-NaF PET/CT scans performed in 14 patients with osseous metastatic disease from prostate cancer and no evidence of locally recurrent or soft-tissue metastatic disease who received chemohormonal therapy. Imaging-based qualitative and semi-quantitative parameters were defined and compared with changes in serum PSA level. RESULTS: Qualitative and semi-quantitative image-based assessments demonstrated > 80% concordance with good correlation (SUVmax κ = 0.71, SUVavg κ = 0.62, SUVsum κ = 0.62). Moderate correlation (κ = 0.43) was found between SUVmax and PSA-based treatment response assessments. There was no statistically significant correlation between PSA-based disease progression and semi-quantitative parameters. Qualitative imaging assessment was moderately correlated (κ = 0.52) with PSA in distinguishing responders and non-responders. CONCLUSION: 18F-NaF PET/CT is complementary to biochemical monitoring in patients with bone-only metastases from prostate cancer which can be helpful in subsequent treatment management decisions.

Prediction of Time to Hormonal Treatment Failure in Metastatic Castration-Sensitive Prostate Cancer with 18F-FDG PET/CT.

The aim of this prospective investigation was to assess the association of 18F-FDG PET/CT with time to hormonal treatment failure (THTF) in men with metastatic castration-sensitive prostate cancer. Methods: 76 men with metastatic castration-sensitive prostate cancer recruited from 2005 to 2011 underwent 18F-FDG PET/CT and were followed prospectively for THTF, defined as treatment change to chemotherapy or death. Patients who had not switched to chemotherapy were censored at the last follow-up date (median of 36 mo; range, 12-108 mo). Cox regression analyses were performed to examine the association between PET/CT measurements: sum of SUVmax, maximum SUVmax, and average SUVmax for up to 10 of the most active lesions and THTF. Survival probabilities were based on the Kaplan-Meier method. Results: 43 patients had hormonal treatment failure, and 8 died without documented treatment failure. Median THTF was 26.5 mo (95% confidence interval [CI], 15.5-46.6 mo). The THTF-free probability at 5 y was 35% ± 6%. On univariate analysis, all PET parameters, including number of lesions, were statistically significant for THTF. In a reduced multivariate model accounting for clinical variables, only sum of SUVmax (hazard ratio, 1.01; 95% CI, 1.002-1.03; P = 0.024) and number of lesions (hazard ratio, 1.18; 95% CI, 1.08-1.29; P < 0.001) were independently associated with THTF. When sum of SUVmax was grouped into quartile ranges, there was a significantly worse survival probability for patients in the fourth-quartile range than in the first, with a univariate hazard ratio of 6.2 (95% CI, 2.8-13.6; P < 0.001). Conclusion: Sum of SUVmax and number of lesions derived from 18F-FDG PET/CT provide independent prognostic information on THTF in men with metastatic castration-sensitive prostate cancer.