Acute and late complications after hypofractionated intensity modulated radiotherapy in prostate cancer

Purpose

The present study compared the complications associated with hypofractionated intensity-modulated radiation therapy (Hypo-IMRT) of prostate cancer to conventionally fractionated IMRT (Conv-IMRT).

Materials and methods

Hypo-IMRT delivered 70 Gy in 28 fractions, whereas Conv-IMRT delivered 78 Gy in 39 fractions. Toxicity was graded with the Common Terminology Criteria for Adverse Events, version 4.0, weekly during radiotherapy, 1 month after radiotherapy, and annually in both patient groups.

Results

The median follow-ups were 39.1 and 38.7 months for patients in the Hypo- and Conv-IMRT groups, respectively. There was no significant difference in rates of acute and late adverse events. The proportions of grade 2 acute genitourinary complications were 48.4 and 51.2% in the Hypo- and Conv-IMRT groups, respectively. The presence of a baseline International Prostate Symptom Score (IPSS) of ten or more was the only significant prognostic factor for grade 2 acute genitourinary toxicity. The incidence of grade 2 late rectal hemorrhage at 3 years was 3.2 and 3.5% in the Hypo- and Conv-IMRT groups, respectively. Small rectal volume was significantly associated with grade 2 late rectal hemorrhage.

Conclusion

Regarding acute and late adverse events, hypofractionated IMRT for prostate cancer was well tolerated and comparable with conventionally fractionated IMRT.Clinical trial registration no. UMIN000003218.

     

Effect of continuous positive airway pressure administration during lung stereotactic ablative radiotherapy: a comparative planning study

Purpose

By increasing lung volume and decreasing respiration-induced tumour motion amplitude, administration of continuous positive airway pressure (CPAP) during stereotactic ablative radiotherapy (SABR) could allow for better sparing of the lungs and heart. In this study, we evaluated the effect of CPAP on lung volume, tumour motion amplitude and baseline shift, as well as the dosimetric impact of the strategy.

Methods

Twenty patients with lung tumours referred for SABR underwent 4D-computed tomography (CT) scans with and without CPAP (CPAP/noCPAP) at two timepoints (T0/T1). First, CPAP and noCPAP scans were compared for lung volume, tumour motion amplitude, and baseline shift. Next, CPAP and noCPAP treatment plans were computed and compared for lung dose parameters (mean lung dose (MLD), lung volume receiving 20 Gy (V_20Gy), 13 Gy (V_13Gy), and 5 Gy (V_5Gy)) and mean heart dose (MHD).

Results

On average, CPAP increased lung volume by 8.0% (p?<?0.001) and 6.3% (p?<?0.001) at T0 and T1, respectively, but did not change tumour motion amplitude or baseline shift. As a result, CPAP administration led to an absolute decrease in MLD, lung V_20Gy, V_13Gy and V_5Gy of 0.1?Gy (p?=?0.1), 0.4% (p?=?0.03), 0.5% (p?=?0.04) and 0.5% (p?=?0.2), respectively, while having no significant influence on MHD.

Conclusions

In patients referred for SABR for lung tumours, CPAP increased lung volume without modifying tumour motion or baseline shift. As a result, CPAP allowed for a slight decrease in radiation dose to the lungs, which is unlikely to be clinically significant.

     

Impact of a rectal and bladder preparation protocol on prostate cancer outcome in patients treated with external beam radiotherapy

Purpose and objective

To test the hypothesis that a rectal and bladder preparation protocol is associated with an increase in prostate cancer specific survival (PCSS), clinical disease free survival (CDFS) and biochemical disease free survival (BDFS).

Patients and methods

From 1999 to 2012, 1080 prostate cancer (PCa) patients were treated with three-dimensional conformal radiotherapy (3DCRT). Of these patients, 761 were treated with an empty rectum and comfortably full bladder (RBP) preparation protocol, while for 319 patients no rectal/bladder preparation (NRBP) protocol was adopted.

Results

Compared with NRBP patients, patients with RBP had significantly higher BDFS (64% vs 48% at 10 years, respectively), CDFS (81% vs 70.5% at 10 years, respectively) and PCSS (95% vs 88% at 10 years, respectively) (log-rank test p < 0.001). Multivariate analysis (MVA) indicated for all treated patients and intermediate high-risk patients that the Gleason score (GS) and the rectal and bladder preparation were the most important prognostic factors for PCSS, CDFS and BDFS. With regard to high- and very high-risk patients, GS, RBP, prostate cancer staging and RT dose were predictors of PCSS, CDFS and BDFS in univariate analysis (UVA).

Conclusion

We found strong evidence that rectal and bladder preparation significantly decreases biochemical and clinical failures and the probability of death from PCa in patients treated without daily image-guided prostate localization, presumably since patients with RBP are able to maintain a reproducibly empty rectum and comfortably full bladder across the whole treatment compared with NRPB patients.

     

<Superscript>18</Superscript>F-FDG uptake by rectal cancer is similar in mucinous and nonmucinous histological subtypes

Purpose

PET/CT has been considered limited for the evaluation of mucinous colorectal tumors due to low ¹⁸F-FDG uptake. The aim of our study was to compare PET/CT variables in mucinous (MC) and nonmucinous (NMC) rectal adenocarcinomas.

Methods

Consecutive patients with cT2-4N0-2M0 rectal cancer included in a prospective clinical trial were reviewed. PET/CT was performed for primary baseline staging. Visual and quantitative analysis included SUVmax and SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG). PET/CT parameters were compared according to histological subtypes.

Results

Overall, 73 patients were included (18 mucinous and 55 nonmucinous). SUVmax values were similar between MC and NMC (19.7 vs. 16.6; p = 0.5). MTV and TLG values were greater in the MC group (103.9 vs. 54.1; p = 0.007 and 892.5 vs. 358.8; p = 0.020) due to larger tumor volumes of MC.

Conclusions

Metabolic parameters at baseline PET/CT for patients with rectal cancer are similar in mucinous and nonmucinous histological subtypes.

     

Can prostatic arterial embolisation (PAE) reduce the volume of the peripheral zone? MRI evaluation of zonal anatomy and infarction after PAE

Objectives

To assess the impact of prostatic arterial embolisation (PAE) on various prostate gland anatomical zones.

Methods

We retrospectively reviewed paired MRI scans obtained before and after PAE for 25 patients and evaluated changes in volumes of the median lobe (ML), central gland (CG), peripheral zone (PZ) and whole prostate gland (WPV) following PAE. We used manual segmentation to calculate volume on axial view T2-weighted images for ML, CG and WPV. We calculated PZ volume by subtracting CG volume from WPV. Enhanced phase on dynamic contrasted-enhanced MRI was used to evaluate the infarction areas after PAE. Clinical results of International Prostate Symptom Score and International Index of Erectile Function questionnaires and the urodynamic study were evaluated before and after PAE.

Results

Significant reductions in volume were observed after PAE for ML (26.2 % decrease), CG (18.8 %), PZ (16.4 %) and WPV (19.1 %; p?<?0.001 for all these volumes). Patients with clinical failure had smaller volume reductions for WPV, ML and CG (all p?<?0.05). Patients with significant CG infarction after PAE displayed larger WPV, ML and CG volume reductions (all p?<?0.01).

Conclusions

PAE can significantly decrease WPV, ML, CG and PZ volumes, and poor clinical outcomes are associated with smaller volume reductions.

Key Points

? The MRI segmentation method provides detailed comparisons of prostate volume change. ? Prostatic arterial embolisation (PAE) decreased central gland and peripheral zone volumes. ? Prostates with infarction after PAE showed larger decreases in volume. ? A larger decrease in prostate volume is associated with clinical success.

     

The retrospective analysis of the relationship between prescribed dose and risk factor for seed migration in iodine-125 prostate brachytherapy

Purpose

The aim was to determine the dose-specific incidence and predictors of seed loss/migration after permanent seed implantation (PI) for localized prostate cancer.

Materials and methods

The records of 79 patients with T1c–T3a prostate cancer who underwent prostate brachytherapy with loose iodine-125 seeds were retrospectively reviewed. Of these patients, 33 with low or intermediate risk underwent PI with the prescribed dose of 160 Gy for the clinical target volume (CTV), and 46 with high risk underwent PI with 110 Gy for the CTV followed by external beam radiotherapy (EBRT) with 45 Gy. Each CTV was defined as a contoured prostate. After PI, the incidence of seed loss/migration was assessed by a series of radiographs.

Results

Seed migration occurred in 22 (0.479 %) of 4589 implanted seeds 1 month after implantation. In PI alone, the number of needles (P = 0.081) and the number of seeds (P = 0.071) showed a trend for a difference between those with and without seed loss. In PI + EBRT, there was a significant difference in the discrepancy between the seed numbers calculated by the nomogram and actually implanted (P = 0.032).

Conclusions

It is suggested that the discrepancy in seed numbers might be the predictor for seed migration in PI with 110 Gy.

     

An IGRT margin concept for pelvic lymph nodes in high-risk prostate cancer

Purpose

Gold-marker-based image-guided radiation therapy (IGRT) of the prostate allows to correct for inter- and intrafraction motion and therefore to safely reduce margins for the prostate planning target volume (PTV). However, pelvic PTVs, when coadministered in a single plan (registered to gold markers [GM]), require reassessment of the margin concept since prostate movement is independent from the pelvic bony anatomy to which the lymphatics are usually referenced to.

Methods

We have therefore revisited prostate translational movement relative to the bony anatomy to obtain adequate margins for the pelvic PTVs compensating mismatch resulting from referencing pelvic target volumes to GMs in the prostate. Prostate movement was analyzed in a set of 28 patients (25 fractions each, totaling in 684 fractions) and the required margins calculated for the pelvic PTVs according to Van Herk’s margin formula \(M=2.5\Upsigma +1.64\left (\sigma^{\prime}-\sigma _{p}\right )\).

Results

The overall mean prostate movement relative to bony anatomy was 0.9 ± 3.1, 0.6 ± 3.4, and 0.0 ± 0.7?mm in anterior/posterior (A/P), inferior/superior (I/S) and left/right (L/R) direction, respectively. Calculated margins to compensate for the resulting mismatch to bony anatomy were 9/9/2?mm in A/P, I/S, and L/R direction and 10/11/6?mm if an additional residual error of 2?mm was assumed.

Conclusion

GM-based IGRT for pelvic PTVs is feasible if margins are adapted accordingly. Margins could be reduced further if systematic errors which are introduced during the planning CT were eliminated.

     

Respiratory gating and multifield technique radiotherapy for esophageal cancer

Purpose

To investigate the effects of a respiratory gating and multifield technique on the dose-volume histogram (DVH) in radiotherapy for esophageal cancer.

Methods and materials

Twenty patients who underwent four-dimensional computed tomography for esophageal cancer were included. We retrospectively created the four treatment plans for each patient, with or without the respiratory gating and multifield technique: No gating-2-field, No gating-4-field, Gating-2-field, and Gating-4-field plans. We compared the DVH parameters of the lung and heart in the No gating-2-field plan with the other three plans.

Result

In the comparison of the parameters in the No gating-2-field plan, there are significant differences in the Lung V_5Gy, V_20Gy, mean dose with all three plans and the Heart V_25Gy–V_40Gy with Gating-2-field plan, V_35Gy, V_40Gy, mean dose with No Gating-4-field plan and V_30Gy–V_40Gy, and mean dose with Gating-4-field plan. The lung parameters were smaller in the Gating-2-field plan and larger in the No gating-4-field and Gating-4-field plans. The heart parameters were all larger in the No gating-2-field plan.

Conclusion

The lung parameters were reduced by the respiratory gating technique and increased by the multifield technique. The heart parameters were reduced by both techniques. It is important to select the optimal technique according to the risk of complications.

     

Hyoscine butylbromide significantly decreases motion artefacts and allows better delineation of anatomic structures in mp-MRI of the prostate

Objectives

To prospectively evaluate the effect of hyoscine butylbromide (HBB) on visualisation of anatomical details and motion-related artefacts in mp-MRI of the prostate at 3.0 Tesla.

Methods

One hundred and three consecutive patients (65?±?10 years) were included in this trial, powered to demonstrate an improvement of image quality after HBB administration, assessed on a 5-point scale by two blinded readers. All patients received high-spatial resolution axial T2-weighted TSE sequences at 3.0 T without spasmolytic agent, repeated after application of 40 mg HBB and followed by routine mp-MRI. Secondary endpoints were (1) susceptibility to side effects, (2) dependence of spasmolytic effect on patients´ weight, and (3) prostate volume.

Results

In 68% of patients, HBB significantly improved the anatomic score (mean 3.4?±?0.9 before and 4.4?±?0.7 after HBB for both readers, p?=?<0.001). In 67%, HBB significantly enhanced the artefact score (mean 3.2?±?1 before and 4.2?±?0.8 after HBB for reader 1, p?=?<0.001; 3.2?±?1 and 4.1?±?0.8 for reader 2, p?=?<0.001). Subgroup analysis revealed no statistically significant difference between patients with different bodyweight or prostate volume. Inter-reader agreement was excellent (k?=?0.95–0.98).

Conclusions

Hyoscine butylbromide significantly improves image quality and reduces motion-related artefacts in mp-MRI of the prostate independent of bodyweight or prostate volume. No side effects were reported.

Key Points

? Hyoscine butylbromide (HBB) improved image quality in over 2/3 of patients. ? Severe artefacts were reduced after HBB in more than 20%. ? The number of non-diagnostic MRI was reduced to <1% after HBB. ? HBB effect was independent of bodyweight and prostate volume. ? No side effects of HBB were reported in this study population.

     

Target tailoring and proton beam therapy to reduce small bowel dose in cervical cancer radiotherapy

Purpose

The aim of the study was to investigate the potential clinical benefit from both target tailoring by excluding the tumour-free proximal part of the uterus during image-guided adaptive radiotherapy (IGART) and improved dose conformity based on intensity-modulated proton therapy (IMPT).

Methods

The study included planning CTs from 11 previously treated patients with cervical cancer with a >4-cm tumour-free part of the proximal uterus on diagnostic magnetic resonance imaging (MRI). IGART and robustly optimised IMPT plans were generated for both conventional target volumes and for MRI-based target tailoring (where the non-invaded proximal part of the uterus was excluded), yielding four treatment plans per patient. For each plan, the V_15Gy, V_30Gy, V_45Gy and D_mean for bladder, sigmoid, rectum and bowel bag were compared, and the normal tissue complication probability (NTCP) for ≥grade 2 acute small bowel toxicity was calculated.

Results

Both IMPT and MRI-based target tailoring resulted in significant reductions in V_15Gy, V_30Gy, V_45Gy and D_mean for bladder and small bowel. IMPT reduced the NTCP for small bowel toxicity from 25% to 18%; this was further reduced to 9% when combined with MRI-based target tailoring. In four of the 11 patients (36%), NTCP reductions of >10% were estimated by IMPT, and in six of the 11 patients (55%) when combined with MRI-based target tailoring. This >10% NTCP reduction was expected if the V_45Gy for bowel bag was >275?cm³ and >200?cm³, respectively, during standard IGART alone.

Conclusions

In patients with cervical cancer, both proton therapy and MRI-based target tailoring lead to a significant reduction in the dose to surrounding organs at risk and small bowel toxicity.

     

Post-transplant lymphoproliferative disorder in the pelvis successfully treated with consolidative radiotherapy

Background

Post-transplant lymphoproliferative disorders (PTLDs) are aggressive malignancies which represent one of the major post-transplant complications. However, treatment options vary significantly and localized disease may be curatively treated with radiotherapy (RT) or surgery. We report a case of recurrent rectal PTLD, which was successfully treated by chemoimmunotherapy followed by RT.

Case presentation

We describe a patient who developed a rectal lymphoproliferative lesion 11 years after kidney transplant, which was successfully treated with consolidative RT using 25.4 Gy sequential to chemoimmunotherapy (R-CHOP). RT was well tolerated and the patient showed no signs of grade 3 or 4 toxicity. This patient is free of recurrence 52 months after RT, with an overall survival of 62 months since diagnosis.

Conclusion

Conventionally fractionated moderate-dose RT appears to be a tolerable and effective treatment option for localized PTLD if a sufficient systemic treatment cannot be applied.

     

Small bowel protection in IMRT for rectal cancer

Background

This treatment planning study analyzes dose coverage and dose to organs at risk (OAR) in intensity-modulated radiotherapy (IMRT) of rectal cancer and compares prone vs. supine positioning as well as the effect of dose optimization for the small bowel (SB) by additional dose constraints in the inverse planning process.

Patients and methods

Based on the CT datasets of ten male patients in both prone and supine position, a total of four different IMRT plans were created for each patient. OAR were defined as the SB, bladder, and femoral heads. In half of the plans, two additional SB cost functions were used in the inverse planning process.

Results

There was a statistically significant dose reduction for the SB in prone position of up to 41% in the high and intermediate dose region, compared with the supine position. Furthermore, the femoral heads showed a significant dose reduction in prone position in the low dose region. Regarding the additional active SB constraints, the dose in the high dose region of the SB was significantly reduced by up to 14% with the additional cost functions. There were no significant differences in the dose distribution of the planning target volume (PTV) and the bladder.

Conclusion

Prone positioning can significantly reduce dose to the SB in IMRT for rectal cancer and therefore should not only be used in 3D conformal radiotherapy but also in IMRT of rectal cancer. Further protection of the SB can be achieved by additional dose constraints in inverse planning without jeopardizing the homogeneity of the PTV.

     

The impact of androgen deprivation therapy on setup errors during external beam radiation therapy for prostate cancer

Purpose

To determine whether setup errors during external beam radiation therapy (RT) for prostate cancer are influenced by the combination of androgen deprivation treatment (ADT) and RT.

Materials and methods

Data from 175 patients treated for prostate cancer were retrospectively analyzed. Treatment was as follows: concurrent ADT plus RT, 33 patients (19%); neoadjuvant and concurrent ADT plus RT, 91 patients (52%); RT only, 51 patients (29%). Required couch shifts without rotations were recorded for each megavoltage (MV) cone beam computed tomography (CBCT) scan, and corresponding alignment shifts were recorded as left–right (x), superior–inferior (y), and anterior–posterior (z). The nonparametric Mann–Whitney test was used to compare shifts by group. Pearson’s correlation coefficient was used to measure the correlation of couch shifts between groups. Mean prostate shifts and standard deviations (SD) were calculated and pooled to obtain mean or group systematic error (M), SD of systematic error (Σ), and SD of random error (σ).

Results

No significant differences were observed in prostate shifts in any direction between the groups. Shifts on CBCT were all less than setup margins. A significant positive correlation was observed between prostate volume and the z?direction prostate shift (r = 0.19, p = 0.04), regardless of ADT group, but not between volume and x? or y?direction shifts (r = 0.04, p = 0.7; r = 0.03, p = 0.7). Random and systematic errors for all patient cohorts and ADT groups were similar.

Conclusion

Hormone therapy given concurrently with RT was not found to significantly impact setup errors. Prostate volume was significantly correlated with shifts in the anterior–posterior direction only.

     

Quantitative magnetic resonance imaging (MRI) morphological analysis of knee cartilage in healthy and anterior cruciate ligament-injured knees

Purpose

To analyze the morphological change in the cartilage of the knee after anterior cruciate ligament (ACL) injury by comparing with that of the intact contralateral knee.

Methods

A total of 22 participants (12 male and 10 female patients) who had unilateral ACL injury underwent MRI scan of both the injured and intact contralateral knees. Sagittal plane images were segmented using a modeling software to determine cartilage volume and cartilage thickness in each part of the knee cartilage that were compared between the ACL-injured and the intact contralateral knees. Furthermore, the male and female patients’ data were analyzed in subgroups.

Results

The ACL-injured knees had statistically significant lower total knee cartilage volume than the intact contralateral knees (P = 0.0020), but had similar mean thickness of total knee cartilage (not significant: n.s.). In the male subgroup, there was no significant difference in cartilage volume and thickness between normal and ACL-injured knees. In the female subgroup, the ACL-injured knees demonstrated statistically significant difference in total knee cartilage volume (P = 0.0004) and thickness (P = 0.0024) compared with the normal knees. The percentage change in the cartilage thickness in women was significantly greater than that in men.

Conclusion

Cartilage volume was significantly smaller in the ACL-injured knees than in the contralateral intact knees in this cohort. Women tended to display greater cartilage volume and thickness change after ACL injury than men. These findings indicated that women might be more susceptible to cartilage alteration after ACL injuries.

Level of evidence

III.

     

Transperineal gold marker implantation for image-guided external beam radiotherapy of prostate cancer

Purpose

To present the feasibility and complications of transperineal fiducial marker implantation in prostate cancer patients undergoing image-guided radiotherapy (IGRT)

Methods and materials

Between November 2011 and April 2016, three radiopaque, gold-plated markers were transperineally implanted into the prostate of 300 patients under transrectal ultrasound guidance and with local anaesthesia. A week after the procedure patients filled in a questionnaire regarding pain, dysuria, urinary frequency, nocturia, rectal bleeding, hematuria, hematospermia or fever symptoms caused by the implantation. Pain was scored on a 1–10 scale, where score 1 meant very weak and score 10 meant unbearable pain. The implanted gold markers were used for daily verification and online correction of patients’ setup during IGRT.

Results

Based on the questionnaires no patient experienced fever, infection, dysuria or rectal bleeding after implantation. Among the 300 patients, 12 (4%) had hematospermia, 43 (14%) hematuria, which lasted for an average of 3.4 and 1.8 days, respectively. The average pain score was 4.6 (range 0–9). Of 300 patients 87 (29%) felt any pain after the intervention, which took an average of 1.5 days. None of the patients needed analgesics after implantation. Overall, 105 patients (35%) reported less, 80 patients (27%) more, and 94 patients (31%) equal amount of pain during marker implantation compared to biopsy. The 21 patients who had a biopsy performed under general anesthesia did not answer this question.

Conclusion

Transperineal gold marker implantation under local anesthesia was well tolerated. Complications were limited; rate and frequency of perioperative pain was comparable to the pain caused by biopsy. The method can be performed safely in clinical practice.

     

Comparative Study Using 100–300 Versus 300–500 μm Microspheres for Symptomatic Patients Due to Enlarged-BPH Prostates

Purpose

The purpose of the study was to compare safety and efficacy outcomes following prostate artery embolization (PAE) for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) with 100–300 versus 300–500 μm tris-acryl gelatin microspheres.

Materials and Methods

Patients were prospectively treated between August 2011 and June 2013 to receive PAE with 100–300 μm (group A) or 300–500 μm (group B) tris-acryl gelatin microspheres. Patients were followed for a minimum of 12 months and were assessed for changes in International Prostate Symptom Score (IPSS), quality of life (QoL) index, prostate volume determined by magnetic resonance imaging, serum prostate specific antigen (PSA), and maximum urine flow rate (Q_max), as well as any treatment-related adverse events.

Results

Fifteen patients were included in each group, and PAE was technically successful in all cases. Both groups experienced significant improvement in mean IPSS, QoL, prostate volume, PSA, and Q_max (p < 0.05 for all). The differences observed between the two groups included a marginally insignificant more adverse events (p = 0.066) and greater mean serum PSA reduction at 3 months of follow-up (p = 0.056) in group A.

Conclusions

Both 100–300 and 300–500 μm microspheres are safe and effective embolic agents for PAE to treat LUTS-related to BPH. Although functional and imaging outcomes did not differ significantly following use of the two embolic sizes, the greater incidence of adverse events with 100–300 μm microspheres suggests that 300–500 μm embolic materials may be more appropriate.

     

MRI features after prostatic artery embolization for the treatment of medium- and large-volume benign hyperplasia

Purpose

To assess magnetic resonance imaging (MRI) features after prostatic artery embolization (PAE) for the treatment of medium- and large-volume benign prostatic hyperplasia and to correlate prostate volume with clinical indexes.

Methods

We retrospectively evaluated 28 patients who underwent PAE. MRI examinations of the prostate were performed to evaluate signal intensity changes and the characteristics of infarcted areas. Prostate volume and the apparent diffusion coefficient (ADC) were measured at an average of 10 days post-PAE and at 1, 3, 6, and 12 months post-PAE. Some clinical indexes were evaluated before and 12 months after PAE. The paired t test, ANOVA, and multiple linear correlation analyses were performed by using the statistical software, SPSS.

Results

All patients experienced prostatic infarction. The prostate volume decreased continuously (p?<?0.05). The ADC values before and after 1, 3, 6, or 12 months of embolization (b?=?1000 and 2000 s/mm²) were statistically significantly different. The ADC values (b?=?3000 s/mm²) were also statistically significantly different before and at each interval time after embolization (p?<?0.05). Prostate volume changes correlated significantly with patient age and post-void residual urine volume (p?<?0.05).

Conclusions

MRI can be used for assessing changes in signal intensity and ADC values of infarction as well as the volume of the prostate after PAE. After PAE, ultrahigh b value diffusion-weighted imaging (DWI) can show early infarction better than lower b value DWI.