Current Status of MRI and PET in the NCCN Guidelines for Prostate Cancer.

Prostate cancer (PCa) represents a significant source of morbidity and mortality for men in the United States, with approximately 1 in 9 being diagnosed with PCa in their lifetime. The role of imaging in the evaluation of men with PCa has evolved and currently plays a central role in diagnosis, treatment planning, and evaluation of recurrence. Appropriate use of multiparametric MRI (mpMRI) and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa while decreasing the detection of clinically insignificant PCa. This process may help patients with clinically insignificant PCa avoid the adverse effects of unnecessary therapy. In the setting of a known PCa, patients with low-grade disease can be observed using active surveillance, which often includes a combination of prostate-specific antigen (PSA) testing, serial mpMRI, and, if indicated, follow-up systematic and targeted TRUS-guided tissue sampling. mpMRI can provide important information in the posttreatment setting, but PET/CT is creating a paradigm shift in imaging standards for patients with locally recurrent and metastatic PCa. This article examines the strengths and limitations of mpMRI for initial PCa diagnosis, active surveillance, recurrent disease evaluation, and image-guided biopsies, and the use of PET/CT imaging in men with recurrent PCa. The goal of this review is to provide a rational basis for current NCCN Clinical Practice Guidelines in Oncology for PCa as they pertain to the use of these advanced imaging modalities.

Prostate Cancer, Version 2.2019, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Guidelines for Prostate Cancer include recommendations regarding diagnosis, risk stratification and workup, treatment options for localized disease, and management of recurrent and advanced disease for clinicians who treat patients with prostate cancer. The portions of the guidelines included herein focus on the roles of germline and somatic genetic testing, risk stratification with nomograms and tumor multigene molecular testing, androgen deprivation therapy, secondary hormonal therapy, chemotherapy, and immunotherapy in patients with prostate cancer.

Quality of life after brachytherapy or bilateral nerve-sparing robot-assisted radical prostatectomy for prostate cancer: a prospective cohort.

OBJECTIVE: To provide comparative data on quality of life (QoL) after prostate cancer treatment to help patients make an informed decision regarding their choice of treatment. METHODS: Patients with pathologically proven, non-metastatic, T1-T3bN0 prostate cancer were included in this prospective non-randomized study if they were to receive treatment with curative intent. Sample size was at least 181 patients per cohort/treatment type. QoL was recorded at baseline and at each follow-up using the Expanded Prostate Cancer Index Composite (EPIC) instrument. The minimal clinically important difference was defined as half of the standard deviation of the baseline score for each domain. A mixed effects model was used to compare the different treatments. Data are presented on the brachytherapy and the bilateral nerve-sparing robot-assisted radical prostatectomy (RARP) cohorts. Hormonotherapy was not allowed. RESULTS: Between November 2007 and January 2013, 181 patients who received brachytherapy and 210 patients who underwent RARP were included. Of the patients who underwent RARP, 178 had bilateral nerve-sparing and were included in the present analysis. Response rate to EPIC questionnaires were higher in the brachytherapy than in the RARP arm: 82% vs 57% at 2 years after treatment and 55% vs 45% at 4 years after treatment. In the mixed effects model, patients in the RARP arm had better QoL with regard to urinary irritation/obstruction or bother and bowel function, and lower QoL regarding sexual function and urinary incontinence. Results were confirmed in a propensity score-matched model. Patient satisfaction was significantly higher in the brachytherapy group at 1, 2 and 3 years after treatment. CONCLUSION: This prospective non-randomized study shows long-term differences in QoL domains after bilateral nerve-sparing RARP and brachytherapy. Differences in patient satisfaction should be further explored. These results could be used to counsel patients in the decision-making process.

Disease reclassification risk with stringent criteria and frequent monitoring in men with favourable-risk prostate cancer undergoing active surveillance.

OBJECTIVES: To determine the frequency of disease reclassification and to identify clinicopathological variables associated with it in patients with favourable-risk prostate cancer undergoing active surveillance (AS). PATIENTS AND METHODS: We assessed 191 men, selected by what may be the most stringent criteria used in AS studies yet conducted, who were enrolled in a prospective cohort AS trial. Clinicopathological characteristics were analysed in a multivariate Cox proportional hazards regression model. Key features were an extended biopsy with a single core positive for Gleason score (GS) 3 + 3 (<3 mm) or 3 + 4 (<2 mm) and a prostate-specific antigen (PSA) level <4 ng/mL (adjusted for prostate volume). Biopsies were repeated every 1-2 years and clinical evaluations every 6 months. Disease was reclassified when PSA level increased by 30% from baseline, or when biopsy tumour length increased beyond the enrolment criteria, more than one positive core was detected or any grade increased to a dominant 4 pattern or any 5 pattern. RESULTS: Disease was reclassified in 32 patients (16.8%) including upgrading to GS 4 + 3 in five patients (2.6%). The median (interquartile range) follow-up time among survivors was 3 (1.9-4.6) years. Overall, 13 of the 32 (40.6%) had incremental increases in GS. Tumour length (hazard ratio 2.95, 95% confidence interval [CI] 1.34-6.46; P = 0.007) and older age (hazard ratio 1.05, 95% CI 1.00-1.09; P = 0.05) were identified as significant and marginally significant predictors of disease reclassification, respectively. Disease remained stable in 83.2% of patients. CONCLUSION: The need persists for improvements in risk stratification and predictive indicators of cancer progression.

Long-term outcomes for men with high-risk prostate cancer treated definitively with external beam radiotherapy with or without androgen deprivation.

BACKGROUND: Men with high-risk prostate cancer are often thought to have very poor outcomes in terms of disease control and survival even after definitive treatment. However, results after external beam radiotherapy have improved significantly through dose escalation and the use of androgen deprivation therapy (ADT). This report describes long-term findings after low-dose (< 75.6 Gy) or high-dose (≥ 75.6 Gy) external beam radiation, with or without ADT. METHODS: This analysis included 741 men with high-risk prostate cancer (clinical classification ≥ T3, Gleason score ≥ 8, or prostate-specific antigen level ≥ 20 ng/mL) treated with external beam radiotherapy at a single tertiary institution from 1987 through 2004. The radiation dose ranged from 60 to 79.3 Gy (median, 70 Gy); 295 men had received ADT for ≥ 2 years, and the median follow-up time was 8.3 years. RESULTS: The 5- and 10-year actuarial overall survival rates were significantly better for men treated with the higher radiation dose (no ADT plus ≥ 75.6 Gy, 87.3% and 72.0%, respectively; and ADT plus ≥ 75.6 Gy, 92.3% and 72%, respectively) (P = .0035). The corresponding 5- and 10-year biochemical failure-free survival rates were significantly better for patients treated with both ADT and higher radiation dose (82% and 77%, P < .0001). At 5 years, men who had not received ADT and had received radiation dose < 75.6 Gy had higher clinical local failure rates than those given ADT and radiation dose ≥ 75.6 Gy (24.2% versus 0%, P < .0001). The 10-year symptomatic local failure rate was only 2% for all patients. CONCLUSIONS: Contrary to lingering historical perceptions, treatment of high-risk prostate cancer with modern, high-dose, external beam radiotherapy and ADT can produce better biochemical, clinical, and survival outcomes over those from previous eras. Specifically, symptomatic local failure is uncommon, and few men die of prostate cancer even 10 or more years after treatment.

Radiation therapy modalities in prostate cancer.

Definitive radiation therapy is the preferred treatment for many men with prostate cancer. Several modalities are used for radiation treatment delivery, including 3-dimensional conformal radiation therapy, intensity-modulated radiation therapy, proton beam therapy, stereotactic body radiation therapy, high-dose-rate prostate brachytherapy, and low-dose-rate prostate brachytherapy. This article reviews technologic advances that have enhanced radiation delivery and describes contemporary radiation treatment techniques for prostate cancer.

Proton therapy for the management of localized prostate cancer: Long-term clinical outcomes at a comprehensive cancer center.

BACKGROUND AND PURPOSE: Proton therapy (PT) has emerged as a standard-of-care treatment option for localized prostate cancer at our comprehensive cancer center. However, there are few large-scale analyses examining the long-term clinical outcomes. Therefore, this article aims to evaluate the long-term effectiveness and toxicity of PT in patients with localized prostate cancer. MATERIALS AND METHODS: Review of 2772 patients treated from May 2006 through January 2020. Disease risk was stratified according to National Comprehensive Cancer Network guidelines as low [LR, n = 640]; favorable-intermediate [F-IR, n = 850]; unfavorable-intermediate [U-IR, n = 851]; high [HR, n = 315]; or very high [VHR, n = 116]. Biochemical failure and toxicity were analyzed using Kaplan-Meier estimates and multivariate models. RESULTS: The median patient age was 66 years; the median follow-up time was 7.0 years. Pelvic lymph node irradiation was prescribed to 28 patients (1%) (2 [0.2%] U-IR, 11 [3.5%] HR, and 15 [12.9%] VHR). The median dose was 78 Gy in 1.8-2.0 Gy(RBE) fractions. Freedom from biochemical relapse (FFBR) rates at 5 years and 10 years were 98.2% and 96.8% for the LR group; 98.3% and 93.6%, F-IR; 94.2% and 90.2%, U-IR; 94.3% and 85.2%, HR; and 86.1% and 68.5%, VHR. Two patients died of prostate cancer. Overall rates of late grade ≥ 3 GU and GI toxicity were 0.87% and 1.01%. CONCLUSIONS: Proton therapy for localized prostate cancer demonstrated excellent clinical outcomes in this large cohort, even among higher-risk groups with historically poor outcomes despite aggressive therapy.

Outcomes after prostate brachytherapy are even better than predicted.

BACKGROUND: During the first 3 years after prostate cancer treatment with radiation therapy, benign prostate-specific antigen (PSA) bounces are difficult for clinicians to distinguish from a biochemical recurrence, which can result in unnecessary interventions and erroneous predictions of outcomes. The objective of this study was to evaluate a commonly used PSA failure definition in a multinational, multi-institutional study after monotherapy with prostate brachytherapy. METHODS: Participants were selected from 2919 men who underwent permanent prostate brachytherapy at the University Medical Center Utrecht, Princess Margaret Hospital, or Seattle Prostate Institute between 1998 and 2006. Inclusion required not having received androgen-deprivation therapy and having at least 30 months of follow-up. Failure was defined as any post-treatment use of hormone therapy, clinical relapse, or prostogram-defined biochemical (PSA) failure. Cases in which the nomogram predicted biochemical failure were evaluated at each institution to verify biochemical status over time and the actual clinical outcome at 5 years. RESULTS: The median follow-up for the 1816 patients was 5.2 years. Concordance between the prostogram-predicted and actual outcomes, as measured by the Harrell c statistic, was 0.655 (95% confidence interval [CI], 0.536-0.774; P = .010) for the Princess Margaret group, 0.493 (95% CI, 0.259-0.648; P = .955) for the Seattle group, and 0.696 (95% CI, 0.648-0.744, P < .001) for the Utrecht group. The overall mean difference in biochemical recurrence-free survival at 5 years between actual outcomes and prostogram-defined outcomes was 9.2% (95% CI, 7.7%-10.6%). The total numbers of prostogram-defined and actual biochemical failures were 312 and 157, respectively (P = .001). CONCLUSIONS: The widely used prostogram could not adequately distinguish a benign PSA bounce from a biochemical recurrence after prostate brachytherapy and could not be used to counsel patients about their predicted outcomes after treatment. The authors conclude that, to avoid unnecessary active interventions after treatment, clinicians should monitor PSA levels for at least 3 years and provide reassurance to patients that a PSA rise during this time is common and may not indicate a treatment failure.

Patient-reported health-related quality of life for men treated with low-dose-rate prostate brachytherapy as monotherapy with 125-iodine, 103-palladium, or 131-cesium: Results of a prospective phase II study.

PURPOSE: To compare quality of life (QoL) after brachytherapy with one of the three approved radioactive isotopes. METHODS AND MATERIALS: Patients with mostly favorable intermediate-risk prostate cancer were treated on this prospective phase II trial with brachytherapy as monotherapy, without hormonal therapy. QoL was recorded at baseline and each follow-up by using the Expanded Prostate Cancer Index Composite instrument. The minimal clinically important difference was defined as half the standard deviation of the baseline score for each domain. Mixed effect models were used to compare the different isotopes, and time-driven activity-based costing was used to compute costs. RESULTS: From 2006 to 2013, 300 patients were treated with iodine-125 (I-125, n = 98, prescribed dose [PD] = 145 Gy), palladium-103 (Pd-103, n = 102, PD = 125 Gy), or cesium-131 (Cs-131, n = 100, PD = 115 Gy). Median age was 64.9 years. Median follow-up time was 5.1 years for the entire cohort, and 7.1, 4.8 and 3.3 years for I-125, Pd-103, and Cs-131 groups, respectively. All three isotope groups showed an initial drop in QoL at first follow-up, which gradually improved over the first 2 years for urinary and bowel domains. QoL profiles were similar between I-125 and Pd-103, whereas Cs-131 showed a statistically significant decrease in QoL regarding bowel and sexual function at 12 months compared with Pd-103. However, these differences did not reach the minimal clinically important difference. Compared with I-125, the use of Pd-103 or Cs-131 resulted in cost increases of 18% and 34% respectively. CONCLUSIONS: The three different isotopes produced a similar QoL profile. Statistically significant differences favored Pd-103/I-125 over Cs-131 for bowel and sexual QoL, but this did not reach clinical significance.

Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer.

PURPOSE: Hypofractionated radiotherapy delivers larger daily doses of radiation and may increase the biologically effective dose delivered to the prostate. We conducted a randomized trial testing the hypothesis that dose-escalated, moderately hypofractionated intensity-modulated radiation therapy (HIMRT) improves prostate cancer control compared with conventionally fractionated IMRT (CIMRT) for men with localized prostate cancer. PATIENTS AND METHODS: Men were randomly assigned to 75.6 Gy in 1.8-Gy fractions delivered over 8.4 weeks (CIMRT) or 72 Gy in 2.4 Gy fractions delivered over 6 weeks (HIMRT, biologically equivalent to 85 Gy in 1.8-Gy fractions assuming prostate cancer α-to-ß ratio of 1.5). Failure was defined as prostate-specific antigen (PSA) failure (nadir plus 2 ng/mL) or initiation of salvage therapy. Modified Radiation Therapy Oncology Group criteria were used to grade late (≥ 90 days after completion of radiotherapy) GI and genitourinary toxicity. RESULTS: Most of the 206 men (72%) had cT1, Gleason score 6 or 7 (99%), and PSA level ≤ 10 ng/mL (90%) disease. Androgen deprivation therapy was received by 24%. With a median follow-up of 8.5 years, men treated with HIMRT experienced fewer treatment failures (n = 10) than men treated with CIMRT (n = 21; P = .036). The 8-year failure rate was 10.7% (95% CI, 5.8% to 19.1%) with HIMRT and 15.4% (95% CI, 9.1% to 25.4%) with CIMRT. There was no difference in overall survival ( P = .39). There was a nonsignificant increase in late grade 2 or 3 GI toxicity with HIMRT (8-year 5.0% v 12.6%; P = .08). However, GI toxicity was only 8.6% when rectal volume receiving 65 Gy of HIMRT was ≤ 15%. Late genitourinary toxicity was similar ( P = .84). There was no grade 4 toxicity. CONCLUSION: The results of this randomized trial demonstrate superior cancer control for men with localized prostate cancer who receive dose-escalated moderately hypofractionation radiotherapy while shortening treatment duration.

Prospective Phase 2 Trial of Permanent Seed Implantation Prostate Brachytherapy for Intermediate-Risk Localized Prostate Cancer: Efficacy, Toxicity, and Quality of Life Outcomes.

PURPOSE: To report the efficacy, physician-reported toxicity, and patient-reported outcomes of men with intermediate-risk prostate cancer after brachytherapy in a prospective phase 2 trial. METHODS AND MATERIALS: This prospective phase 2 trial involved 300 patients with previously untreated prostate cancer treated from 2006 through 2013. Eligible patients had ≤cT2b (T3 excluded according to magnetic resonance imaging), Gleason score (GS) 6 with prostate-specific antigen (PSA) level 10-15 ng/mL, or GS 7 with PSA <10 ng/mL, and were treated with prostate brachytherapy (without hormonal therapy). RESULTS: Median patient age was 64.9 years; 3.7% had GS 6, 78.7% had GS 7 (3+4), and 17.7% had GS 7 (4+3). Median follow-up time was 5.1 years. Median PSA at 5 years was 0.01 ng/mL (range, 0-6.0 ng/mL). Ten biochemical failures occurred, for a 5-year freedom from biochemical failure rate of 97.3% (95% confidence interval [CI], 95.1-99.5), and 16 patients died, only 1 from prostate cancer, for 5-year rates of overall and biochemical progression-free survival of 94.9% (95% CI, 92.1-97.9) and 92.7% (95% CI, 89.3-96.2%). Four patients had late grade 3 genitourinary toxicity, and 2 patients had late grade 3 rectal toxicity; no grade 4 or 5 toxicity was observed. Rates of "moderate or big problems" at 4 years were 7.4% for urinary (vs 0.4% at baseline), 2.9% bowel (vs 0.4%), and 29.7% sexual function (vs 19.7%). Most men were "satisfied or extremely satisfied" (91% at 2 years after treatment and 93% at 4 years). CONCLUSIONS: Brachytherapy monotherapy is safe and effective and leads to good quality of life for some men with localized intermediate-risk prostate cancer.

Patient-reported Urinary, Bowel, and Sexual Function After Hypofractionated Intensity-modulated Radiation Therapy for Prostate Cancer: Results From a Randomized Trial.

OBJECTIVES: Hypofractionated prostate radiotherapy may increase biologically effective dose delivered while shortening treatment duration, but information on patient-reported urinary, bowel, and sexual function after dose-escalated hypofractionated radiotherapy is limited. We report patient-reported outcomes (PROs) from a randomized trial comparing hypofractionated and conventional prostate radiotherapy. METHODS: Men with localized prostate cancer were enrolled in a trial that randomized men to either conventionally fractionated intensity-modulated radiation therapy (CIMRT, 75.6 Gy in 1.8 Gy fractions) or to dose-escalated hypofractionated IMRT (HIMRT, 72 Gy in 2.4 Gy fractions). Questionnaires assessing urinary, bowel, and sexual function were completed pretreatment and at 2, 3, 4, and 5 years after treatment. RESULTS: Of 203 eligible patients, 185 were evaluable for PROs. A total of 173 completed the pretreatment questionnaire (82 CIMRT, 91 HIMRT) and 102 completed the 2-year questionnaire (46 CIMRT, 56 HIMRT). Patients who completed PROs were similar to those who did not complete PROs (all P>0.05). Patient characteristics, clinical characteristics, and baseline symptoms were well balanced between the treatment arms (all P>0.05). There was no difference in patient-reported bowel (urgency, control, frequency, or blood per rectum), urinary (dysuria, hematuria, nocturia, leakage), or sexual symptoms (erections firm enough for intercourse) between treatment arms at 2, 3, 4, and 5 years after treatment (all P>0.01). Concordance between physician-assessed toxicity and PROs varied across urinary and bowel domains. DISCUSSION: We did not detect an increase in patient-reported urinary, bowel, and sexual symptom burden after dose-escalated intensity-modulated prostate radiation therapy using a moderate hypofractionation regimen (72 Gy in 2.4 Gy fractions) compared with conventionally fractionated radiation.

Prophylactic cranial irradiation for patients with lung cancer.

The central nervous system is a common site of metastasis in patients with small cell lung cancer (SCLC) and non-small-cell lung cancer. Despite advances in combined modality therapy, intracranial relapse continues to be a common site of recurrence and a major cause of morbidity for patients with lung cancer. Prophylactic cranial irradiation (PCI) has proven to be effective in reducing the incidence of brain metastases in patients with lung cancer. Based upon results of a metaanalysis demonstrating a small improvement in overall survival, PCI is now routinely offered to patients with limited-stage SCLC after a complete or near-complete response to initial treatment. However, many questions remain unanswered regarding the optimal dose, fractionation, and toxicity of PCI in patients with limited-stage SCLC. Additionally, the role of PCI in patients with extensive-stage SCLC and locally advanced non-small-cell lung cancer is unclear. Several important collaborative group trials are under way in an attempt to further define the role of PCI in patients with lung cancer.

Magnetic resonance imaging in prostate brachytherapy: Evidence, clinical end points to data, and direction forward.

The integration of multiparametric MRI into prostate brachytherapy has become a subject of interest over the past 2 decades. MRI directed high-dose-rate and low-dose-rate prostate brachytherapy offers the potential to improve treatment accuracy and standardize postprocedure quality. This article reviews the evidence to date on MRI utilization in prostate brachytherapy and postulates future pathways for MRI integration.

Implementation of hypofractionated prostate radiation therapy in the United States: A National Cancer Database analysis.

PURPOSE: Preclinical and clinical research over the past several decades suggests that hypofractionated (HFxn) radiation therapy schedules produce similar treatment outcomes compared with conventionally fractionated (CFxn) radiation therapy for definitive treatment of localized prostate cancer (PCa). We sought to evaluate national trends and identify factors associated with HFxn utilization using the US National Cancer Database. METHODS AND MATERIALS: We queried the National Cancer Database for men diagnosed with localized (N0,M0) PCa from 2004 through 2013 treated with external beam radiation therapy. Patients were grouped by dose per fraction (DpF) in Gray: CFxn was defined as DpF ≤2.0, moderate HFxn as DpF >2.0 but <5.0, and extreme HFxn as DpF ≥5.0. Men receiving DpF <1.5 or >15.0 were excluded, as were those receiving <25 or >90 Gy total dose. Multiple logistic regression was performed to identify demographic, clinical, and treatment factor associations. RESULTS: A total of 132,403 men were identified, with 120,055 receiving CFxn, 7264 moderate HFxn, and 5084 extreme HFxn. Although CFxn was by far the most common approach over the analysis period, HFxn use increased from 6.2% in 2004 to 14.2% in 2013 (P < .01). Extreme HFxn use increased the most (from 0.3% to 8.5%), whereas moderate HFxn utilization was unchanged (from 5.9% to 5.7%). HFxn use was independently associated with younger age, later year of diagnosis, non-black race, non-Medicaid insurance, non-Western residence, higher income, academic treatment facility, greater distance from treatment facility, low-risk disease group (by National Comprehensive Cancer Network criteria), and nonreceipt of hormone therapy. CONCLUSIONS: Although CFxn remains the most common radiation therapy schedule for localized PCa, use of HFxn appears to be increasing in the United States as a result of increased extreme HFxn use. Financial and logistical factors may accelerate adoption of shorter schedules. Considering the multiple demographic and prognostic differences identified between these groups, randomized outcome data comparing extreme HFxn to alternatives are desirable.

Patient characterization and usage trends of proton beam therapy for localized prostate cancer in the United States: A study of the National Cancer Database.

PURPOSE: To evaluate usage trends and identify factors associated with proton beam therapy (PBT) compared to alternative forms of external beam radiation therapy (RT) (EBRT) for localized prostate cancer. PATIENTS AND METHODS: The National Cancer Database was queried for men with localized (N0, M0) prostate cancer diagnosed between 2004 and 2013, treated with EBRT, with available data on EBRT modality (photon vs. PBT). Binary multiple logistic regression identified variables associated with EBRT modality. RESULTS: In total, 143,702 patients were evaluated with relatively few men receiving PBT (5,709 [4.0%]). Significant differences in patient and clinical characteristics were identified between those men treated with PBT compared to those treated with photon (odds ratio [OR]; 95% CI). Patients treated with PBT were generally younger (OR = 0.73; CI: 0.67-0.82), National Comprehensive Cancer Network low-risk compared to intermediate (0.71; 0.65-0.78) or high (0.44; 0.38-0.5) risk, white vs. black race (0.66; 0.58-0.77), with less comorbidity (Charlson-Deyo 0 vs. 2+; 0.70; 0.50-0.98), live in higher income counties (1.55; 1.36-1.78), and live in metropolitan areas compared to urban (0.21; 0.18-0.23) or rural (0.14; 0.10-0.19) areas. Most patients treated with PBT travelled more than 100 miles to the treatment facility. Annual PBT utilization significantly increased in both total number and percentage of EBRT over time (2.7%-5.6%; P<0.001). PBT utilization increased mostly in men classified as National Comprehensive Cancer Network low-risk (4%-10.2%). CONCLUSION: PBT for men with localized prostate cancer significantly increased in the United States from 2004 to 2013. Significant demographic and prognostic differences between those men treated with photons and protons were identified.

Prostate brachytherapy, either alone or in combination with external beam radiation, is associated with longer overall survival in men with favorable pathologic Group 4 (Gleason score 8) prostate cancer.

PURPOSE: Conventional prostate cancer risk stratification results in considerable heterogeneity within each prognostic group. Men with pathologic grade Group 4 (Gleason score 8) but otherwise low-risk features have been identified as a favorable subset of high-risk prostate cancer. Given recent randomized data supporting improved cancer outcome with brachytherapy in intermediate- and high-risk prostate cancer, we sought to evaluate brachytherapy utilization and overall survival (OS) for these patients. METHODS AND MATERIALS: We queried the National Cancer Database for clinical T1c-T2a N0 M0 prostate cancer with prostate-specific antigen <10 ng/mL and Gleason score 8 adenocarcinoma on biopsy. All patients received androgen deprivation therapy and either external beam radiation therapy (EBRT) alone, brachytherapy alone, or a combination of EBRT with brachytherapy boost (brachytherapy + EBRT). Kaplan-Meier OS estimates as well as univariate and multivariate Cox proportional hazards regression analyses were performed. Propensity score-matched analyses were performed to further control for baseline confounders. RESULTS: Four thousand four hundred ninety-six patients were identified with a median followup of 62.5 months (range, 2.3-119.8). Median age was 72 years (range, 41-90+). Utilization of brachytherapy decreased from 2004 to 2009. The odds ratio for brachytherapy by year (continuous variable) was 0.86 (p < 0.001). Five-year OS was 84%, 88%, and 89% for the EBRT alone, brachytherapy alone, and brachytherapy + EBRT groups, respectively. On multivariate analysis, higher median income, low comorbidity score, and treatment with brachytherapy alone (hazard ratio, 0.66; p = 0.005) or brachytherapy + EBRT (hazard ratio, 0.70; p = 0.001) remained associated with longer OS. Propensity score matching confirmed longer OS associated with either brachytherapy regimen. CONCLUSIONS: Of those men with World Health Organization pathologic grade Group 4 (Gleason score 8) prostate cancer and otherwise favorable prognostic features treated with androgen deprivation therapy and radiation therapy, longer OS was achieved when prostate brachytherapy was included, whether used alone or in combination with supplemental EBRT. In spite of these excellent outcomes, prostate brachytherapy utilization is declining in the United States.

Permanent prostate brachytherapy postimplant magnetic resonance imaging dosimetry using positive contrast magnetic resonance imaging markers.

PURPOSE: Permanent prostate brachytherapy dosimetry using computed tomography-magnetic resonance imaging (CT-MRI) fusion combines the anatomic detail of MRI with seed localization on CT but requires multimodality imaging acquisition and fusion. The purpose of this study was to compare the utility of MRI only postimplant dosimetry to standard CT-MRI fusion-based dosimetry. METHODS AND MATERIALS: Twenty-three patients undergoing permanent prostate brachytherapy with use of positive contrast MRI markers were included in this study. Dose calculation to the whole prostate, apex, mid-gland, and base was performed via standard CT-MRI fusion and MRI only dosimetry with prostate delineated on the same T2 MRI sequence. The 3-dimensional (3D) distances between seed positions of these two methods were also evaluated. Wilcoxon-matched-pair signed-rank test compared the D90 and V100 of the prostate and its sectors between methods. RESULTS: The day 0 D90 and V100 for the prostate were 98% versus 94% and 88% versus 86% for CT-MRI fusion and MRI only dosimetry. There were no differences in the D90 or V100 of the whole prostate, mid-gland, or base between dosimetric methods (p > 0.19), but prostate apex D90 was high by 13% with MRI dosimetry (p = 0.034). The average distance between seeds on CT-MRI fusion and MRI alone was 5.5 mm. After additional automated rigid registration of 3D seed positions, the average distance between seeds was 0.3 mm, and the previously observed differences in apex dose between methods was eliminated (p > 0.11). CONCLUSIONS: Permanent prostate brachytherapy dosimetry based only on MRI using positive contrast MRI markers is feasible, accurate, and reduces the uncertainties arising from CT-MRI fusion abating the need for postimplant multimodality imaging.