Faculty Bibliography

OBJECTIVE:To examine a set of proposed eligibility factors for hemi-ablative focal therapy in prostate cancer and to determine the likelihood of residual extensive disease. METHODS:We retrospectively analyzed data from 98 patients with unilateral prostate cancer on biopsy with detailed tumor maps from whole-mount slides and preoperative magnetic resonance imaging data. These patients met the focal therapy consensus meeting inclusion criteria (prostate-specific antigen <15 ng/mL, clinical stage T1c-T2a and Gleason score 3 + 3 or 3 + 4 on needle biopsy), and underwent radical prostatectomy between 2000 and 2014. Extensive disease was defined as having Gleason pattern 4/5 in bilateral lobes, any extraprostatic extension, seminal vesicle invasion or lymph node invasion. Both lobes of the prostate were scored on magnetic resonance imaging. Preoperative characteristics including biopsy and magnetic resonance imaging data were used to predict extensive disease. RESULTS:, 17 patients had pathological tumor stage ≥3 and one patient had lymph node invasion. CONCLUSIONS:An important number of patients meeting the focal therapy consensus meeting inclusion criteria can present extensive disease. Further studies using targeted biopsies might provide more accurate information about the selection of focal therapy candidates.

PURPOSE/OBJECTIVE:Provide evidence- and expert-based recommendations for optimal use of imaging in advanced prostate cancer. Due to increases in research and utilization of novel imaging for advanced prostate cancer, this guideline is intended to outline techniques available and provide recommendations on appropriate use of imaging for specified patient subgroups. METHODS:An Expert Panel was convened with members from ASCO and the Society of Abdominal Radiology, American College of Radiology, Society of Nuclear Medicine and Molecular Imaging, American Urological Association, American Society for Radiation Oncology, and Society of Urologic Oncology to conduct a systematic review of the literature and develop an evidence-based guideline on the optimal use of imaging for advanced prostate cancer. Representative index cases of various prostate cancer disease states are presented, including suspected high-risk disease, newly diagnosed treatment-naïve metastatic disease, suspected recurrent disease after local treatment, and progressive disease while undergoing systemic treatment. A systematic review of the literature from 2013 to August 2018 identified fully published English-language systematic reviews with or without meta-analyses, reports of rigorously conducted phase III randomized controlled trials that compared ≥ 2 imaging modalities, and noncomparative studies that reported on the efficacy of a single imaging modality. RESULTS:A total of 35 studies met inclusion criteria and form the evidence base, including 17 systematic reviews with or without meta-analysis and 18 primary research articles. RECOMMENDATIONS/CONCLUSIONS:One or more of these imaging modalities should be used for patients with advanced prostate cancer: conventional imaging (defined as computed tomography [CT], bone scan, and/or prostate magnetic resonance imaging [MRI]) and/or next-generation imaging (NGI), positron emission tomography [PET], PET/CT, PET/MRI, or whole-body MRI) according to the clinical scenario.

Metabolic imaging using hyperpolarized magnetic resonance can increase the sensitivity of MRI, though its ability to inform on relevant changes to biochemistry in humans remains unclear. In this work, we image pyruvate metabolism in patients, assessing the reproducibility of delivery and conversion in the setting of primary prostate cancer. We show that the time to max of pyruvate does not vary significantly within patients undergoing two separate injections or across patients. Furthermore, we show that lactate increases with Gleason grade. RNA sequencing data demonstrate a significant increase in the predominant pyruvate uptake transporter, monocarboxylate transporter 1. Increased protein expression was also observed in regions of high lactate signal, implicating it as the driver of lactate signal in vivo. Targeted DNA sequencing for actionable mutations revealed the highest lactate occurred in patients with PTEN loss. This work identifies a potential link between actionable genomic alterations and metabolic information derived from hyperpolarized pyruvate MRI.

Mucinous adenocarcinoma of the urachal remnant is a nonurothelial malignancy that may be asymptomatic until locally advanced or metastatic. We describe a 37-year-old woman with invasive ductal breast carcinoma who underwent ¹⁸Fluorine-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) computed tomography (CT) demonstrating a non-FDG avid pelvic mass, initially suspected to represent a pedunculated uterine fibroid. Magnetic resonance imaging revealed a mixed solid-cystic mass separate from the uterus, suspicious for urachal neoplasm, confirmed as mucinous adenocarcinoma on histopathology. Urachal tumors may not be FDG-avid and represent a potential pitfall on FDG PET/CT.

PURPOSE:To determine if the primary treatment approach (primary debulking surgery (PDS) versus neoadjuvant chemotherapy and interval debulking surgery (NACT-IDS)) influences the pattern of first recurrence in patients with completely cytoreduced advanced high-grade serous ovarian carcinoma (HGSOC). MATERIALS AND METHODS:This retrospective study included 178 patients with newly diagnosed stage IIIC-IV HGSOC, complete gross resection during PDS (n = 124) or IDS (n = 54) from January 2008-March 2013, and baseline and first recurrence contrast-enhanced computed tomography scans. Clinical characteristics and number of disease sites at baseline were analyzed for associations with time to recurrence. In 135 patients who experienced recurrence, the overlap in disease locations between baseline and recurrence and the number of new disease locations at recurrence were analyzed according to the primary treatment approach. RESULTS:At univariate and multivariate analyses, NACT-IDS was associated with more overlapping locations between baseline and first recurrence (p ≤ 0.003) and fewer recurrences in new anatomic locations (p ≤ 0.043) compared with PDS. The same results were found in a subgroup that received intra-peritoneal adjuvant chemotherapy after either treatment approach. At univariate analysis, patient age, primary treatment approach, adjuvant chemotherapy route, and number of disease locations at baseline were associated with time to recurrence (p ≤ 0.009). At multivariate analysis, older patient age, NACT-IDS, and greater disease locations at baseline remained significant (p ≤ 0.018). CONCLUSION:The distribution of disease at the time of first recurrence varied with the choice of primary treatment. Compared to patients treated with PDS, patients who underwent NACT-IDS experienced recurrence more often in the same locations as the original disease.

Gestational trophoblastic disease (GTD), a rare complication of pregnancy, includes both benign and malignant forms, the latter collectively referred to as gestational trophoblastic neoplasia (GTN). When metastatic, the lungs are the most common site of initial spread. Beta-human chorionic gonadotropin, elaborated to some extent by all forms of GTD, is useful in facilitating disease detection, diagnosis, monitoring treatment response, and follow-up. Imaging evaluation depends on whether GTD manifests in one of its benign forms or whether it has progressed to GTN. Transabdominal and transvaginal ultrasound with duplex Doppler evaluation of the pelvis are usually appropriate diagnostic procedures in either of these circumstances, and in posttreatment surveillance. The appropriateness of more extensive imaging remains dependent on a diagnosis of GTN and on other factors. The use of imaging to assess complications, typically hemorrhagic, should be guided by the location of clinical signs and symptoms. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

CONTEXT:Recent studies suggested that magnetic resonance imaging (MRI) followed by targeted biopsy ("MRI-stratified pathway") detects more clinically significant prostate cancers (csPCa) than the systematic transrectal ultrasound-guided prostate biopsy (TRUS-Bx) pathway, but controversy persists. Several randomized clinical trials (RCTs) were recently published, enabling generation of higher-level evidence to evaluate this hypothesis. OBJECTIVE:To perform a systematic review and meta-analysis of RCTs comparing the detection rates of csPCa in the MRI-stratified pathway and the systematic TRUS-Bx pathway in patients with a suspicion of prostate cancer (PCa). EVIDENCE ACQUISITION:PubMed, EMBASE, and Cochrane databases were searched up to March 18, 2019. RCTs reporting csPCa detection rates of both pathways in patients with a clinical suspicion of prostate cancer were included. Relative csPCa detection rates of the MRI-stratified pathway were pooled using random-effect model. Study quality was assessed using the Cochrane risk of bias tool for randomized trials. A comparison of detection rates of clinically insignificant PCa (cisPCa) and any PCa was also performed. EVIDENCE SYNTHESIS:Nine RCTs (2908 patients) were included. The MRI-stratified pathway detected more csPCa than the TRUS-Bx pathway (relative detection rate 1.45 [95% confidence interval {CI} 1.09-1.92] for all patients, and 1.42 [95% CI 1.02-1.97] and 1.60 [95% CI 1.01-2.54] for biopsy-naïve and prior negative biopsy patients, respectively). Detection rates were not significantly different between pathways for cisPCa (0.89 [95% CI 0.49-1.62]), but higher in the MRI-stratified pathway for the detection of any PCa (1.39 [95% CI 1.05-1.84]). CONCLUSIONS:The MRI-stratified pathway detected more csPCa than the systematic TRUS-guided biopsy pathway in men with a clinical suspicion of PCa, for both biopsy-naïve patients and those with prior negative biopsy. The detection rate of any PCa was higher in the MRI-stratified pathway, but not significantly different from that of cisPCa. PATIENT SUMMARY:Our meta-analysis of clinical trials shows that the magnetic resonance imaging-stratified pathway detects more clinically significant prostate cancers than the transrectal ultrasound-guided prostate biopsy pathway in men with a suspicion of prostate cancer.

PURPOSE/OBJECTIVE:The use of magnetic resonance imaging (MRI) for radiation therapy simulation is growing because of its ability to provide excellent delineation of target tissue and organs at risk. With the use of hypofractionated schemes in prostate cancer, urethral sparing is essential; however, visualization of the prostatic urethra can be challenging because of the presence of benign prostatic hyperplasia as well as respiratory motion artifacts. The goal of this study was to compare the utility of 2 motion-insensitive, T2-weighted MRI pulse sequences for urethra visualization in the setting of MRI-based simulation. METHODS AND MATERIALS/METHODS:Twenty-two patients undergoing MRI simulation without Foley catheters were imaged on a 3 Tesla MRI scanner between October 2018 and January 2019. Sagittal multislice data were acquired using (1) MultiVane XD radial sampling with parallel imaging acceleration (MVXD) and (2) single-shot fast-spin-echo (SSFSE) sequences with acquisition times of 2 to 3 minutes per sequence. For each examination, 2 genitourinary radiologists scored prostatic urethra visibility on a 1-to-5 scale and rated the signal-to-noise ratio and the presence of artifacts in each series. RESULTS:Urethral visibility was scored higher in the MVXD series than in the SSFSE series in 18 of 22 cases (Reader 1) and 17 of 22 cases (Reader 2). The differences in scores between MVXD and SSFSE were statistically significant for both readers (P < .0001 for both, paired Student's t-test) and interobserver agreement was high (Cohen's kappa = 0.67). Both readers found the signal-to-noise ratio of the MVXD sequence to be superior in all cases. The MVXD sequence was found to generate more artifacts than the SSFSE sequence, but these tended to appear in the periphery and did not affect the ability to visualize the urethra. CONCLUSIONS:A radial T2-weighted multislice pulse sequence was superior to an SSFSE sequence for visualization of the urethra in the setting of magnetic resonance simulation for prostate cancer.

Prostate cancer is a very heterogeneous disease, and contemporary management is focused on identification and treatment of the prognostically adverse high-risk tumors while minimizing overtreatment of indolent, low-risk tumors. In recent years, imaging has gained increasing importance in the detection, staging, posttreatment assessment, and detection of recurrence of prostate cancer. Several imaging modalities including conventional and functional methods are used in different clinical scenarios with their very own advantages and limitations. This continuing medical education article provides an overview of available imaging modalities currently in use for prostate cancer followed by a more specific section on the value of these different imaging modalities in distinct clinical scenarios, ranging from initial diagnosis to advanced, metastatic castration-resistant prostate cancer. In addition to established imaging indications, we will highlight some potential future applications of contemporary imaging modalities in prostate cancer.

Tumor heterogeneity in ovarian cancer has been reported at the histological and genetic levels and is associated with adverse clinical outcomes. Tumor evaluation using standard computed tomography or magnetic resonance imaging techniques does not account for the intra- or inter-tumoral heterogeneity in advanced ovarian cancer with peritoneal carcinomatosis. As such, computational approaches in assessing tumor heterogeneity have been proposed using radiomics and radiogenomics in order to analyze the whole tumor heterogeneity as opposed to single biopsy sampling. As part of radiomics, texture analysis, which includes the extraction of multiple data from images has been proposed recently to evaluate advanced ovarian tumor heterogeneity. In this short review, we explain the basics of radiomics, how to perform texture analysis, and its applications to ovarian cancer imaging.