Growing the global cancer care system: success stories from around the world and lessons for the future.

Despite significant biomedical advancements in various realms of oncology, the benefits of these developments are not equitably distributed, particularly in under-resourced settings. While much work has described the challenges and systemic barriers in global cancer control, in this essay we focus on success stories. This piece describes clinical care delivered at Rwanda's Butaro Cancer Center of Excellence, the cancer research collaborations under India's National Cancer Grid, and the efforts of Latin America's Institute of Cancer of São Paulo in advancing cancer care and training. These examples highlight the potential of strategic collaborations and resource allocation strategies in improving cancer care globally. We emphasize the critical role of partnerships between physicians and allied health professionals, funders, and policymakers in enhancing access to treatment and infrastructure, advancing contextualized research and national guidelines, and establishing regional and global collaborations. We also draw attention to challenges faced in diverse global settings and outline benchmarks to measure success in the fight against cancer.

Combined artificial intelligence and radiologist model for predicting rectal cancer treatment response from magnetic resonance imaging: an external validation study.

PURPOSE: To evaluate an MRI-based radiomic texture classifier alone and combined with radiologist qualitative assessment in predicting pathological complete response (pCR) using restaging MRI with internal training and external validation. METHODS: Consecutive patients with locally advanced rectal cancer (LARC) who underwent neoadjuvant therapy followed by total mesorectal excision from March 2012 to February 2016 (Memorial Sloan Kettering Cancer Center/internal dataset, n = 114, 41% female, median age = 55) and July 2014 to October 2015 (Instituto do Câncer do Estado de São Paulo/external dataset, n = 50, 52% female, median age = 64.5) were retrospectively included. Two radiologists (R1, senior; R2, junior) independently evaluated restaging MRI, classifying patients (radiological complete response vs radiological partial response). Model A (n = 33 texture features), model B (n = 91 features including texture, shape, and edge features), and two combination models (model A + B + R1, model A + B + R2) were constructed. Pathology served as the reference standard for neoadjuvant treatment response. Comparison of the classifiers' AUCs on the external set was done using DeLong's test. RESULTS: Models A and B had similar discriminative ability (P = 0.3; Model B AUC = 83%, 95% CI 70%-97%). Combined models increased inter-reader agreement compared with radiologist-only interpretation (κ = 0.82, 95% CI 0.70-0.89 vs k = 0.25, 95% CI 0.11-0.61). The combined model slightly increased junior radiologist specificity, positive predictive value, and negative predictive values (93% vs 90%, 57% vs 50%, and 91% vs 90%, respectively). CONCLUSION: We developed and externally validated a combined model using radiomics and radiologist qualitative assessment, which improved inter-reader agreement and slightly increased the diagnostic performance of the junior radiologist in predicting pCR after neoadjuvant treatment in patients with LARC.

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

BACKGROUND: Despite the multitude of clinical manifestations of post-acute sequelae of SARS-CoV-2 infection (PASC), studies applying statistical methods to directly investigate patterns of symptom co-occurrence and their biological correlates are scarce. METHODS: We assessed 30 symptoms pertaining to different organ systems in 749 adults (age = 55 ± 14 years; 47% female) during in-person visits conducted at 6-11 months after hospitalization due to coronavirus disease 2019 (COVID-19), including six psychiatric and cognitive manifestations. Symptom co-occurrence was initially investigated using exploratory factor analysis (EFA), and latent variable modeling was then conducted using Item Response Theory (IRT). We investigated associations of latent variable severity with objective indices of persistent physical disability, pulmonary and kidney dysfunction, and C-reactive protein and D-dimer blood levels, measured at the same follow-up assessment. RESULTS: The EFA extracted one factor, explaining 64.8% of variance; loadings were positive for all symptoms, and above 0.35 for 16 of them. The latent trait generated using IRT placed fatigue, psychiatric, and cognitive manifestations as the most discriminative symptoms (coefficients > 1.5, p < 0.001). Latent trait severity was associated with decreased body weight and poorer physical performance (coefficients > 0.240; p ⩽ 0.003), and elevated blood levels of C-reactive protein (coefficient = 0.378; 95% CI 0.215-0.541; p < 0.001) and D-dimer (coefficient = 0.412; 95% CI 0.123-0.702; p = 0.005). Results were similar after excluding subjects with pro-inflammatory comorbidities. CONCLUSIONS: Different symptoms that persist for several months after moderate or severe COVID-19 may unite within one latent trait of PASC. This trait is dominated by fatigue and psychiatric symptoms, and is associated with objective signs of physical disability and persistent systemic inflammation.

Value of Primary Rectal Tumor PET/MRI in the Prediction of Synchronic Metastatic Disease.

PURPOSE: To analyze the associations between positron emission tomography (PET)/magnetic resonance imaging (MRI) features for primary rectal tumors and metastases. PROCEDURES: Between November 2016 and April 2018, 101 patients with rectal adenocarcinoma were included in this prospective study (NCT02537340) for whole-body PET/MRI for baseline staging. Two readers analyzed the PET/MRI; they assessed the semiquantitative PET features of the primary tumor and the N- and M-stages. Another reader analyzed the MRI features for locoregional staging. The reference standard for confirming metastatic disease was biopsy or imaging follow-up. Non-parametric tests were used to compare the PET/MRI features of the participants with or without metastatic disease. Binary logistic regression was used to evaluate the associations between the primary tumor PET/MRI features and metastatic disease. RESULTS: A total of 101 consecutive participants (median age 62 years; range: 33-87 years) were included. Metastases were detected in 35.6% (36 of 101) of the participants. Among the PET/MRI features, higher tumor lesion glycolysis (352.95 vs 242.70; P = .46) and metabolic tumor volume (36.15 vs 26.20; P = .03) were more frequent in patients with than in those without metastases. Additionally, patients with metastases had a higher incidence of PET-positive (64% vs 32%; P = .009) and MRI-positive (56% vs 32%; P = .03) mesorectal lymph nodes, extramural vascular invasion (86% vs 49%; P > .001), and involvement of mesorectal fascia (64% vs 42%; P = .04); there were also differences between the mrT stages of these two groups (P = .008). No differences in the maximum standardized uptake values for the primary tumors in patients with and without metastases were observed (18.9 vs 19.1; P = .56). Multivariable logistic regression showed that extramural vascular invasion on MRI was the only significant predictor (adjusted odds ratio, 3.8 [95% CI: 1.1, 13.9]; P = .001). CONCLUSION: PET/MRI facilitated the identification of participants with a high risk of metastatic disease, though these findings were based mainly on MRI features.

Percutaneous thermoablation of small renal masses (T1a) in surgical candidate patients: oncologic outcomes.

OBJECTIVE: To evaluate the local tumour progression-free survival (LTPFS), metastasis-free survival (MFS), cancer-specific survival (CSS) and overall survival (OS) of healthy surgical candidates who underwent percutaneous thermoablation (TA) as a first-line therapy for small renal masses (T1a). METHODS: The institutional review board approved this bi-institutional retrospective study of 85 consecutive surgical candidates with 97 biopsy-proven malignant renal masses (T1a) treated with percutaneous TA from 2008 to 2016. The LTPFS, MFS, CSS and OS rates were calculated using the Kaplan-Meier method. Descriptive analysis was also performed. RESULTS: The median tumour size was 2.3 cm (range, 0.7-3.9 cm). The minimal and mean follow-up periods were 24 and 56 months, respectively. Local recurrence was detected in four patients (4.7%) at 8.5, 13.8, 58.0 and 64.0 months of follow-up and retreated successfully with percutaneous TA. No patient developed metastatic renal cell carcinoma, and none died due to renal oncologic complications. One patient died of heart attack. The 5-year LTPFS, OS, MFS and CSS rates were 93.0%, 98.4%, 100% and 100%, respectively. Only two patients (2.3%) had major complications (Clavien-Dindo grade > II), including ureteropelvic junction stenosis and urinary obstruction due to ureteral blood clots. CONCLUSIONS: Our study demonstrates that percutaneous TA is a feasible and effective first-line therapy for healthy surgical candidates with small renal masses (T1a). The 5-year LTPFS, OS, CSS and MFS rates were 93.0%, 98.4%, 100% and 100%, respectively, with a major complication rate of only 2.3%. KEY POINTS: • Image-guided percutaneous thermoablation of small renal malignancies was effective in 95.3% of the healthy surgical candidates. • Major complications were detected in 2.3% of the patients. • The local tumour progression-free survival rate was 97.6% and 93.0% at 3 and 5 years, respectively.

Diagnostic accuracy of FDG-PET/MRI versus pelvic MRI and thoracic and abdominal CT for detecting synchronous distant metastases in rectal cancer patients.

PURPOSE: We compared the diagnostic accuracy of detecting distant metastases for baseline rectal cancer staging between PET/MRI and conventional staging (CS). MATERIALS AND METHODS: This prospective study from November 2016 to April 2018 included 101 rectal adenocarcinoma patients for primary staging. These patients underwent whole-body PET/MRI in addition to CS (pelvic MRI and thoracic and abdominal contrast-enhanced CT). Different readers analyzed CS and PET/MRI findings for primary tumor, nodal, and metastatic staging. The presence, number, and location of metastases were recorded according to the organ involved (non-regional lymph nodes (LNs), liver, lungs, or others). Lesions were defined as positive, negative, or indeterminate. The number of lesions per organ was limited to 10. The McNemar test was used to compare the accuracies. RESULTS: PET/MRI exhibited a higher accuracy in detecting metastatic disease than CS in all patients (88.4% vs. 82.6%, p = 0.003) and in patients with extramural vascular invasion (EMVI) (88.9% vs. 85.5%, p = 0.013). The detection rate of PET/MRI was superior to that of CS for all lesions [84.1% vs. 68.9%, p = 0.001], as well as those in the liver (89.2% vs. 84.2%), non-regional LNs (90.0% vs. 36.7%), and lungs (76.4% vs. 66.9%). PET/MRI correctly classified 19/33 (57.5%) patients with indeterminate lesions on CS. CONCLUSION: PET/MRI yields higher accuracy than CS for detecting distant synchronous metastases in the baseline staging of patients with rectal cancer and EMVI. PET/MRI exhibited a higher detection rate than CS for identifying non-regional LNs, hepatic lesions, and pulmonary lesions as well as correctly classifying patients with indeterminate lesions. TRIAL REGISTRATION: NCT02537340.

Reassessing Patterns of Response to Immunotherapy with PET: From Morphology to Metabolism.

Cancer demands precise evaluation and accurate and timely assessment of response to treatment. Imaging must be performed early during therapy to allow adjustments to the course of treatment. For decades, cross-sectional imaging provided these answers, showing responses to the treatment through changes in tumor size. However, with the emergence of immune checkpoint inhibitors, complex immune response patterns were revealed that have quickly highlighted the limitations of this approach. Patterns of response beyond tumor size have been recognized and include cystic degeneration, necrosis, hemorrhage, and cavitation. Furthermore, new unique patterns of response have surfaced, like pseudoprogression and hyperprogression, while other patterns were shown to be deceptive, such as unconfirmed progressive disease. This evolution led to new therapeutic evaluation criteria adapted specifically for immunotherapy. Moreover, inflammatory adverse effects of the immune checkpoint blockade were identified, many of which were life threatening and requiring prompt intervention. Given complex concepts like tumor microenvironment and novel therapeutic modalities in the era of personalized medicine, increasingly sophisticated imaging techniques are required to address the intricate patterns of behavior of different neoplasms. Fluorine 18-fluorodeoxyglucose PET/CT has rapidly emerged as one such technique that spans both molecular biology and immunology. This imaging technique is potentially capable of identifying and tracking prognostic biomarkers owing to its combined use of anatomic and metabolic imaging, which enables it to characterize biologic processes in vivo. This tailored approach may provide whole-body quantification of the metabolic burden of disease, providing enhanced prediction of treatment response and improved detection of adverse events. ©RSNA, 2020.

PET/MRI Characterization of Mucinous Versus Nonmucinous Components of Rectal Adenocarcinoma: A Comparison of Tumor Metabolism and Cellularity.

OBJECTIVE. The purpose of this study was to evaluate whether FDG PET/MRI can be used to differentiate the mucinous from the nonmucinous components of primary rectal tumors and to compare the glycolytic metabolism on PET with tumor cellularity on DWI in both components. SUBJECTS AND METHODS. Ninety-nine patients who underwent FDG PET/MRI for staging of primary rectal cancer were included in this prospective analysis. MRI depicted the mucin component through the tumor volume. Separate volumes of interest were drawn on both mucinous and nonmucinous components and propagated to PET and apparent diffusion coefficient (ADC) mapping. Maximum and mean standardized uptake values (SUVmax, SUVmean) and maximum, mean, and minimum ADC values (ADCmax, ADCmean, ADCmin) were recorded and compared between areas with mucinous and nonmucinous components. Whole-body PET/MRI was also used to evaluate for the presence of distant metastases. Nonparametric testing was used to compare the two groups of patients: those with tumors with a mucinous component and those with tumors without a mucinous component. Logistic regression analysis was performed to calculate the association risk between mucinous component and metastatic disease. RESULTS. Seventeen patients (17.2%) had a mucinous component within the tumor on T2-weighted MRI. Most of these patients had advanced disease, the mucinous component tumors being in significantly higher T categories than the tumors without a mucinous component (88.2% vs 61.0%; p = 0.032). SUVmax (7.4 vs 16.7; p = 0.002) and SUVmean (5.4 vs 13.4; p = 0.001) were significantly lower in tumors with a mucinous component than in those without a mucinous component. Tumor ADC measurements were not different between tumors with and those without a mucinous component (ADCmean, 1.4 vs 1.6; p = 0.361). There was no association between presence of a mucinous component within the primary rectal tumor and presence of synchronous metastases (odds ratio, 1.1 [0.4-3.0]; p = 0.904). Moreover, the occurrence of metastases in patients with mucinous component tumors (7/17 [41.2%]) was not different from that in patients with tumors without a mucinous component (28/82 [34.1%]) (p = 0.887). CONCLUSION. PET/MRI can be used to differentiate the mucinous and nonmucinous components within primary rectal adenocarcinoma on the basis of metabolic status. The FDG uptake is significantly lower in the mucinous component, but tumor cellularity based on MRI and DWI findings is not. Despite being associated with a higher T category in the sample of patients in this study, the presence of a mucinous component seems not to be associated with increased risk of synchronous metastases.

Theranostics in Nuclear Medicine: Emerging and Re-emerging Integrated Imaging and Therapies in the Era of Precision Oncology.

Theranostics refers to the pairing of diagnostic biomarkers with therapeutic agents that share a specific target in diseased cells or tissues. Nuclear medicine, particularly with regard to applications in oncology, is currently one of the greatest components of the theranostic concept in clinical and research scenarios. Theranostics in nuclear medicine, or nuclear theranostics, refers to the use of radioactive compounds to image biologic phenomena by means of expression of specific disease targets such as cell surface receptors or membrane transporters, and then to use specifically designed agents to deliver ionizing radiation to the tissues that express these targets. The nuclear theranostic approach has sparked increasing interest and gained importance in parallel to the growth in molecular imaging and personalized medicine, helping to provide customized management for various diseases; improving patient selection, prediction of response and toxicity, and determination of prognosis; and avoiding futile and costly diagnostic examinations and treatment of many diseases. The authors provide an overview of theranostic approaches in nuclear medicine, starting with a review of the main concepts and unique features of nuclear theranostics and aided by a retrospective discussion of the progress of theranostic agents since early applications, with illustrative cases emphasizing the imaging features. Advanced concepts regarding the role of fluorine 18-fluorodeoxyglucose PET in theranostics, as well as developments in and future directions of theranostics, are discussed. ©RSNA, 2020 See discussion on this article by Greenspan and Jadvar.

Association between perivascular inflammation and downstream myocardial perfusion in patients with suspected coronary artery disease.

AIMS: To investigate the association between pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation derived from coronary computed tomography angiography (CTA) and coronary flow reserve (CFR) by positron emission tomography (PET) in patients with suspected coronary artery disease (CAD). METHODS AND RESULTS: PCAT CT attenuation was measured in proximal segments of all major epicardial coronary vessels of 105 patients with suspected CAD. We evaluated the relationship between PCAT CT attenuation and other quantitative/qualitative CT-derived anatomic parameters with CFR by PET. Overall, the mean age was 60 ± 12 years and 93% had intermediate pre-test probability of obstructive CAD. Obstructive CAD (≥50% stenosis) was detected in 37 (35.2%) patients and impaired CFR (<2.0) in 32 (30.5%) patients. On a per-vessel analysis (315 vessels), obstructive CAD, non-calcified plaque volume, and PCAT CT attenuation were independently associated with CFR. In patients with coronary calcium score (CCS) <100, those with high-PCAT CT attenuation presented significantly lower CFR values than those with low-PCAT CT attenuation (2.47 ± 0.95 vs. 3.13 ± 0.89, P = 0.003). Among those without obstructive CAD, CFR was significantly lower in patients with high-PCAT CT attenuation (2.51 ± 0.95 vs. 3.02 ± 0.84, P = 0.021). CONCLUSION: Coronary perivascular inflammation by CTA was independently associated with downstream myocardial perfusion by PET. In patients with low CCS or without obstructive CAD, CFR was lower in the presence of higher perivascular inflammation. PCAT CT attenuation might help identifying myocardial ischaemia particularly among patients who are traditionally considered non-high risk for future cardiovascular events.

Audiovisual Sexual Stimulation Improves Diagnostic Accuracy of Penile Doppler Ultrasound in Patients With Erectile Dysfunction.

INTRODUCTION: Although penile Doppler ultrasound (PDU) is a useful tool in evaluating erectile dysfunction (ED), an optimal erectile response might be limited because of an increased sympathetic discharge. Audiovisual sexual stimulation (AVSS) has been suggested to help improving PDU performance. AIM: To evaluate the use of AVSS as a tool to improve diagnostic accuracy of PDU studies. METHODS: A total of 40 men (mean age: 61.8 ± 10.2 years) with ED were enrolled. PDU sessions were performed in a randomized fashion as follows: session A under intracavernous injection (ICI) alone and session B under ICI and AVSS with 7-day interval between sessions. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) were measured 5, 10, 15, and 20 minutes after ICI. MAIN OUTCOME MEASURE: Comparisons between PSV, EDV, and RI values were performed with and without AVSS. Univariable and multivariable analyses including clinical and demographic parameters were performed to evaluate predictors of an abnormal PDU. RESULTS: 23 patients performed the first session without AVSS, and 17 performed the first session with AVSS. EDV and RI were better in AVSS session (p = 0.022 and 0.019). PSV was not influenced by AVSS (p = 0.768). The proportion of patients whose diagnosis was changed because of the AVSS was 4 of 40 (10.0%, 95% confidence interval [CI]: 2.8-23.7%). Of 12 patients with venous leak observed on the PDU without AVSS, 3 turned into normal after AVSS (25.0%, 95% CI: 5.5-57.2%). Of 4 men with arterial insufficiency observed on the PDU on ICI alone, 1 became normal after AVSS (25.0%, 95% CI: 0.6-80.6%). International Index of Erectile Function-5 scores were lower in patients with abnormal PDU (6.3 ± 3.3 vs 12.0 ± 5.8, p=0.003). On multivariable analysis, DM and International Index of Erectile Function-5 scores were the only independent predictors of abnormal PDU studies. CLINICAL IMPLICATIONS: False diagnoses of venous leak during PDU with ICI could be a result of an increased adrenergic discharge during the examination. Routine AVSS may be helpful to avoid error in diagnosis. STRENGTH & LIMITATIONS: The study has randomized the use of AVSS in different session orders. Only one previously published study has used this strategy to control the accommodation effect in repeat studies, a common source of bias in the PDU literature. The main limitation is the absence of a rigidity assessment and a redosing protocol. CONCLUSION: Adding AVSS during PDU improves ICI response and may help clinicians evaluate penile hemodynamics more accurately. Carneiro F, Nascimento B, Miranda EP, et al. Audiovisual Sexual Stimulation Improves Diagnostic Accuracy of Penile Doppler Ultrasound in Patients With Erectile Dysfunction. J Sex Med 2020;17:249-256.

Impact of 5-Alpha-Reductase Inhibitors Use at the Time of Prostatic Artery Embolization for Treatment of Benign Prostatic Obstruction.

PURPOSE: To compare the 12-month post-prostatic artery embolization (PAE) clinical outcomes of patients who were and were not taking 5-alpha-reductase inhibitors (5ARIs) at the time of PAE. MATERIALS AND METHODS: A retrospective review was conducted of patients who underwent PAE from 2010 to 2017 due to lower urinary tract symptoms, secondary to benign prostatic hyperplasia (BPH). One hundred fifty-five patients were included and divided in 2 groups; these groups did not present statistically significant differences in their baseline characteristics-those taking 5ARIs (Y-5ARIs, n = 40) and those not taking 5ARIs (N-5ARIs, n = 115). International Prostate Symptom Score (IPSS), the sub-item Quality of Life (QoL), and the incidence of clinical failure were used as primary endpoints. Secondary endpoints included mean prostate volume reduction and mean peak flow rate (Qmax) improvement. Clinical failure or recurrence was defined as absence of symptomatic improvement (IPSS ≥ 8 or QoL ≥ 3) or the need for invasive BPH treatment (PAE or transurethral resection of the prostate) during the 12-month follow-up period. RESULTS: After 12-month follow-up, IPSS, QoL, and prostatic volume were significantly lower compared to baseline in both groups, and Qmax showed a significant increase. No statistically significant differences were observed in outcomes between N-5ARIs and Y-5ARIs, and the clinical failure rate for both groups was approximately 20%. CONCLUSIONS: The use of 5ARIs did not show a detrimental effect on clinical outcomes of PAE, in either subjective (IPSS, QoL, and clinical failure) or objective (prostatic volume and Qmax) parameters.

Revisiting Prostate Cancer Recurrence with PSMA PET: Atlas of Typical and Atypical Patterns of Spread.

The introduction of prostate-specific membrane antigen (PSMA) in clinical practice has revolutionized evaluation of biochemical recurrence of prostate cancer after curative-intent treatment. The high expression of this glycoprotein in prostate cancer cells makes PSMA imaging superior to the current conventional staging methods, namely bone scanning and CT. The high capability of PSMA imaging for identifying very small previously undetected lesions has been widely demonstrated in the literature, leading to a rethinking of patient management by oncologists, urologists, and radiation oncologists. The typical and predictable patterns of spread in prostate cancer are still more prevalent, such as spread to pelvic lymph nodes and bone metastasis, but different patterns of disease spread are becoming more commonly recognized with higher reliability because PSMA imaging allows detection of more typical and atypical lesions than conventional imaging. Furthermore, it is important for the reading physician to recognize and understand the typical disease spread and the most prevalent atypical prostate cancer relapses, not only to heighten the relevancy of reports but also to improve imaging consultancy in multispecialty oncologic practice. ©RSNA, 2019.

Predicting malignant neck lymphadenopathy using color duplex sonography based on multivariate analysis.

PURPOSE: To select the best predictors of cervical lymph node malignancy based on gray-scale and power Doppler sonography using multivariate analysis. METHODS: We evaluated sonographically a total of 97 lymph nodes in the neck that were subjected to fine-needle aspiration biopsy. The gray-scale and power Doppler sonography parameters that we analyzed using multivariate logistic regression included size, shape, echogenicity, echotexture, margins, hilum, presence of microcalcifications or necrosis, vascularization, and resistance index (RI). RESULTS: The three variables with a diagnostic accuracy exceeding 80% were an altered vascularization, heterogeneous echotexture, and abnormal hilum. Malignant nodes exhibited higher RI and larger sizes than benign nodes, and the best cutoff values to distinguish malignant from benign lymph nodes were an RI of 0.77 and a short axis ≥ 0.9 cm. Altered vascularization, a short axis ≥ 0.9 cm, and abnormal hilum were the best predictors of malignancy. CONCLUSIONS: The best sonographic predictors of lymph node malignancy are, in descending order, an altered vascularization, a short axis ≥ 0.9 cm, an abnormal hilum, and a heterogeneous echotexture. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:587-594, 2016.

Magnetic Resonance-Guided High-Intensity Focused Ultrasound Ablation of Osteoid Osteoma: A Case Series Report.

Osteoid osteoma is painful benign tumor. The aim of this study was to report our initial experience using magnetic resonance-guided focused ultrasound to treat osteoid osteomas. This retrospective single-center study included four patients treated with magnetic resonance-guided focused ultrasound. They presented with severe pain with reduced quality of life and a poor response to clinical treatment. The pre- and post-treatment evaluation comprised computed tomography and magnetic resonance imaging and focused on quality of life and the impact of pain on daily activities. After treatment, three patients had complete pain resolution with no recurrence. One patient had a recurrence of symptoms after 2 wk and underwent a new successful treatment with increased energy levels. On average, 13 sonications were administered (8-18 sonications/treatment) with an average energy of 2,003 J (range: 1,063-3,522 J). Magnetic resonance-guided focused ultrasound appears to be a feasible, tolerable and effective treatment in selected patients with osteoid osteomas.

MRI findings after prostatic artery embolization for treatment of benign hyperplasia.

OBJECTIVE: The purpose of this article is to assess and describe the MRI findings after prostatic artery embolization for treatment of benign prostatic hyperplasia. MATERIALS AND METHODS: We retrospectively evaluated 17 patients who underwent prostatic artery embolization as part of different prospective studies to evaluate this alternative treatment of benign prostatic hyperplasia. Clinical results were evaluated by assessment of urinary catheterization and International Prostate Symptom Score (IPSS). Serial MRI examinations were performed, and the prostatic central gland and peripheral zone were evaluated for signal intensity changes and the presence and characteristics of infarcted areas. Statistical analysis was performed with ANOVA for repeated measures and Student t test. RESULTS: All patients had clinical success, as defined by the removal of indwelling urinary catheter or decreased IPSS after embolization. Infarcts were seen in 70.6% of the subjects, exclusively in the central gland, were almost always characterized by hyperintensity on T1-weighted images and predominant hypointensity on T2-weighted images, and became smaller (mean reduction, p < 0.001) and isointense to the remaining of the central gland over time. Volume reduction of the prostate after embolization was significant (averaging 32.0% after 12-18 months; p < 0.001) only in patients with infarcts. No statistically significant association was seen between the development of infarcts and IPSS. CONCLUSION: MRI can be used for assessing the development of infarcts and volume reduction in the prostate after embolization. Further studies are needed to correlate these findings to clinical outcome.