Comparison of dose-escalated,image-guided radiotherapy vs. dose-escalated,high-dose-rate brachytherapy boost in a modern cohort of intermediate-risk prostate cancer patients

PurposeWe compared outcomes in intermediate-risk prostate cancer patients treated with dose-escalated adaptive image-guided radiation therapy (IGRT) or dose-escalated high-dose-rate brachytherapy boost (HDR-B).Methods and MaterialsPatients with intermediate-risk prostate cancer by National Comprehensive Cancer Network criteria were treated with either CT-based off-line adaptive IGRT (n = 734) or HDR-B (n = 282). IGRT was delivered with 3D-conformal or intensity-modulated radiation therapy with a median dose of 77.4 Gy. For HDR-B, the whole pelvis received a median 46 Gy, and the prostate 2 implants of 9.5 Gy (n = 71), 10.5 Gy (n = 155), or 11.5 Gy (n = 56).ResultsMedian followup was 3.7 years for IGRT and 8.0 years for HDR-B (p < 0.001). Eight-year biochemical control was 86% for IGRT and 91% for HDR-B (p = 0.22), disease-free survival 67% for IGRT and 79% for HDR-B (p = 0.006), and overall survival 75% for IGRT and 86% for HDR-B (p = 0.009). Cause-specific survival (8-year, 100% vs. 99%), freedom from distant metastases (98% vs. 97%), and freedom from local recurrence (98% vs. 98%) did not differ (p > 0.50 each). A worse prognosis group was defined by percent positive prostate biopsy cores >50%, perineural invasion, or stage T2b–c, encompassing 260 (35%) IGRT and 171 (61%) HDR-B patients. These patients evidenced a 5-year biochemical control of 96% for HDR-B and 87% for IGRT (p = 0.002).ConclusionsDose-escalated IGRT and HDR-B both yield excellent clinical outcomes for patients with intermediate-risk prostate cancer. Improved biochemical control with HDR-B for patients with worse pretreatment characteristics suggests that a subgroup of intermediate-risk prostate cancer patients may benefit from dual-modality treatment.     

Gleason score 7 prostate cancer treated with interstitial brachytherapy with or without supplemental external beam radiation and androgen deprivation therapy: Is the primary pattern on needle biopsy prognostic?

PurposeTo evaluate the effect of primary Gleason pattern on biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) in Gleason 7 prostate cancer patients treated with low-dose-rate (LDR) interstitial brachytherapy with or without supplemental external beam radiation therapy and androgen deprivation therapy.Methods and MaterialsWe retrospectively reviewed the medical records of 932 consecutive patients with biopsy-confirmed Gleason 7 prostate cancer who received LDR interstitial brachytherapy as a component of their definitive treatment regimen. Treatment outcomes were compared between patients with primary Gleason pattern 3 and 4.ResultsWith a median followup of 7.4 years, the 10- and 14-year bPFS, CSS, and OS for the entire Gleason 7 study group were 95.7/95.7%, 98.6/98.6% and 77.2/64.3%, respectively. When biochemical control was evaluated as a function of primary Gleason pattern, the primary pattern 3 had a statistically higher 10- and 14-year bPFS (97.8/97.8% vs. 93.1/93.1%, p = 0.006). The Gleason pattern 3 patients also trended toward a higher 10- and 14-year CSS (99.3/99.3% vs. 96.9/96.9%, p = 0.058). OS was not statistically different between the two Gleason 7 cohorts.ConclusionsGleason 7 prostate cancer patients treated with LDR interstitial brachytherapy have an excellent long-term outcome. There was a small but statistically significant advantage in bPFS and a trend toward improved CSS in patients with a primary Gleason pattern of 3.     

Salvage brachytherapy for recurrent prostate cancer

PurposeTo evaluate the role of salvage prostate brachytherapy for locally recurrent prostate cancer after external beam radiation alone.Methods and MaterialsSixty-nine consecutive patients treated with salvage brachytherapy after a local failure were analyzed. All patients were found to have pathologic proven recurrent prostate cancer at least 2 years after initial therapy and no regional or distant disease on imaging studies. Pd-103 was used with a prescribed pD₉₀ of 100 Gy. In total, 89.9% of patients received androgen suppression (AS) as part of their salvage therapy. Patients whose prostate-specific antigen >5.0 ng/mL while on AS were considered to have castration resistant prostate cancer (CRPC). Patients on AS >6 months before salvage brachytherapy were considered to have delayed therapy. Patients retreated within 5 years after their initial treatment were considered to have early failures.ResultsTotal median followup after salvage therapy was 5.0 years (0.6–13.7). From the date of salvage, 5-year biochemical control for low-risk patients was 85.6%, intermediate-risk patients 74.8%, and high-risk patients 66%. Five-year biochemical control was 73.8% for non-CRPC and 22% for CRPC cases (<0.001). Including and excluding CRPC cases, early treatment after failure vs. delayed treatment was significantly better (p < 0.05). Chronic adverse events were seen in few patients, with genitourinary Grade 3 toxicity of 8.7% and no genitourinary Grade 4 or gastrointestinal Grade 3 or higher toxicities.ConclusionsA subset of failures after definitive radiation is local in nature, and excellent control is possible with salvage brachytherapy.     

HDR brachytherapy as monotherapy for prostate cancer: A systematic review with meta-analysis

PurposeThe effectiveness and safety of high dose brachytherapy as monotherapy (HDR-BRT-M) in prostate cancer is limited to retrospective studies. We performed a meta-analysis to summarize existing data and identify trends in biochemical recurrence-free survival (bRFS) and toxicity after HDR-BRT-M in patients with prostate cancer.Methods and MaterialsRetrospective, prospective, or randomized clinical trials were identified on electronical databases through June 2020. We followed the PRISMA and MOOSE guidelines. A meta-regression analysis was performed to assess if there is a relationship between moderator variables and bRFS. A p-value < 0.05 was considered significant.ResultsFourteen studies with a total of 3534 patients treated were included. The cumulative size of the bRFS at 5 years was 0.92 (95% confidence interval (CI) 0.48–0.61). The five-year bRFS for low, intermediate, and high risk was 97.5% (95% CI 96–98%), 93.5% (95% CI 91–96%), and 91% (95% CI 88–93%), respectively. The total biological effective dose (BED) (p = 0.02), the BED per fraction (p = 0.001), androgen deprivation therapy usage (p = 0.04), and the number of fractions of HDR-BRT-M (p = 0.024) were significantly associated with bRFS rate. The rate of late Grade 2/3 or > genitourinary and gastrointestinal toxicity was 22.4% (95% CI 9–35,2%)/1.4% (95% CI 0.8–2.1%) and 2.7% (95% CI 0–6.8%) and 0.2% (95% CI 0.1%–0.4%), respectively.ConclusionsHDR-BRT-M is safe with excellent rates of bRFS for all risk groups. The total BED, the BED per fraction, and number of fractions were the key factors associated with the biochemical control. These data can be useful to choose the size and number of BRT fractionation.     

Intraprostatic calcification and biochemical recurrence in men treated with cesium-131 prostate brachytherapy

PURPOSEBaseline intraprostatic calcification (IC) has been shown to be associated with a higher rate of biochemical recurrence (BCR) in men treated with iodine-125 prostate brachytherapy (PB). We evaluated this association in a cohort of men treated with cesium-131 PB.METHODS AND MATERIALSWe retrospectively reviewed the charts of all low- and intermediate-risk prostate cancer patients treated with cesium-131 PB +/- external beam radiotherapy (EBRT) at our institution from 2/2011 to 7/2018. Patients with < 24 months of follow up or those who received androgen deprivation therapy were excluded. Baseline IC status (defined as one or more ICs ≥ 5 mm) was determined on post-PB CT scans. Cox analysis was used to assess predictors of BCR and Kaplan–Meier survival curves were calculated.RESULTSTwo hundred and sixteen low- and intermediate-risk prostate cancer patients treated with cesium-131 PB +/- EBRT were included. Median follow up was 56.9 months (range 24.1–111.4). Overall, 76 (35.2%) patients had baseline IC and 140 (64.8%) did not. Baseline disease characteristics did not differ significantly between groups. On univariate Cox analysis, only risk group (p = 0.047) and initial PSA (p = 0.016) were significant predictors of BCR, whereas baseline IC was not (p = 0.11). The 5-year BCR-free survival in patients with versus without baseline IC was 97.7% versus 93.8% (p = 0.405), respectively.CONCLUSIONSIn a cohort of low- and intermediate-risk prostate cancer patients treated with cesium-131 PB, the rate of BCR in men with baseline IC was low and baseline IC was not associated with a higher risk of BCR.     

Knife or needles? A cohort analysis of outcomes after radical prostatectomy or brachytherapy for men with low- or intermediate-risk adenocarcinoma of the prostate

PurposeThe purpose of this study was to evaluate long-term outcomes for men with early stage prostate cancer treated with radical prostatectomy (RP) or brachytherapy (BT) at a single tertiary care center.Methods and MaterialsWe retrospectively analyzed data from 371 men with clinical T1a–T2c disease with prostate-specific antigen level <20 ng/mL and Gleason score (GS) 6–7 who were treated with RP (n = 279) or BT (n = 92) at MD Anderson Cancer Center in 2000–2001. Biochemical recurrence–free survival (BRFS) and prostate cancer–specific survival rates were compared by treatment modality.ResultsThe median followup time was 7.2 and 7.6 years for patients treated with RP and BT, respectively. Disease was upgraded from GS 6 to 7 after central review of the biopsy specimen for 36 men treated with RP (12.9%) and 15 men treated with BT (16.3%). After RP, GS was upgraded in 121 men (43.4%) between the centrally reviewed biopsy and the RP specimen. After RP, 5-year BRFS rates were 96.1% and 90.6% for low- and intermediate-risk disease, respectively (p = 0.003). After BT, 5-year BRFS rates were 92.5% and 95.8% for low- and intermediate-risk disease, respectively (p = 0.017). After RP or BT, 5-year BRFS rates were not significantly different with GS upgraded. Five-year prostate cancer–specific survival rates for patients with upgraded GS were 100% for both RP and BT.ConclusionsExcellent disease control outcomes can be achieved after either RP or BT as monotherapy for men with early stage prostate cancer. Upgrading of GS from 6 to 7, either (3 + 4) or (4 + 3), did not predict for worse outcomes.     

Racial differences in the PSA bounce in predicting prostate cancer outcomes after brachytherapy: Evidence from the Department of Veterans Affairs

PurposeAfrican American men have historically had poorer prostate cancer biochemical and survival outcomes than Caucasians. However, emerging data suggest nononcologic factors drive much of this disparity. Prior evidence has suggested an association between a transient prostate specific antigen (PSA) bounce and improved biochemical control. However, racial differences in this relationship have remained relatively unexplored.Methods and MaterialsWe identified 4477 men treated for low- or intermediate-risk prostate cancer within the U.S. Department of Veterans Affairs (VA) from 2000 to 2010 with brachytherapy alone or in combination with external beam radiotherapy without androgen deprivation. Longitudinal PSA data were used to define to biochemical failure and PSA bounce. Cox proportional hazard models were used explore racial differences in the relationship between the PSA bounce and time to biochemical failure.ResultsThirty-one percent of our sample experienced a PSA bounce, with African Americans more likely to experience a bounce (42%) compared with Caucasians (29%); p < 0.001. Despite this, African Americans had a higher likelihood of biochemical failure (hazard ratio [HR] 1.4; p = 0.006). However, African American men experiencing a PSA bounce were less likely to experience a biochemical failure (HR = 0.64; p = 0.046), whereas this relationship was not statistically significant for Caucasians (HR = 0.78; p = 0.092). On multivariate analysis, African Americans receiving brachytherapy alone were most sensitive to the protective benefit of the PSA bounce (HR = 0.64).ConclusionsA PSA bounce was associated with improved biochemical control among patients receiving brachytherapy as part of their treatment for low- or intermediate-risk prostate cancer at the VA. African American men treated with brachytherapy had a particularly pronounced biochemical control benefit of a PSA bounce.     

The association of intraprostatic calcifications and dosimetry parameters with biochemical control after permanent prostate implant

PurposeThe objective of this study was to evaluate the impact of intraprostatic calcifications (IC) on long-term tumor control in patients treated with permanent implant prostate brachytherapy (PIPB).Materials and MethodsData from 609 I-125 patients treated with PIPB were retrospectively reviewed. The presence of IC was determined by reviewing postimplant CT images. Doses delivered were determined using the Monte Carlo (model-based) calculations and the TG43 approach. Biochemical relapses at 7 and 10 years were determined according to Phoenix definition. Long-term biochemical relapse-free survival (bRFS) was determined using Kaplan–Meier estimates with log rank test. Cox proportional hazard models were used for analysis of predictor factors of biochemical recurrence.ResultsIC were observed for 11.1% of patients. Clinical stage, PSA, Gleason score, D'Amico risk group, and ADT use were comparable between IC and no IC groups. The 7- and 10-year bRFS for the entire cohort were 94.1% and 90.6%, respectively. The bRFS at 7 years was 90.5% (with IC) vs. 94.5% (without IC) (p = 0.198); the corresponding values at 10 years were 78.8% vs. 91.8% (p = 0.046). On Cox model, only prostatic calcifications were a significant risk factor for biochemical relapse (HR: 2.30, IC 95%: 1.05–5.00, p = 0.037; and HR: 3.94; IC 95%: 1.00–15.38; p = 0.049 for univariate and multivariate analysis, respectively).ConclusionThe presence of IC in patients treated with PIPB decreases V₁₀₀ and D₉₀ for postimplant Monte Carlo dosimetry (compared with TG43); correspondingly, IC are associated with a lower 10-y bRFS. Model-based dose calculations are critical to evaluate potential cold spots due to calcifications.     

Early outcomes of high-dose-rate brachytherapy combined with ultra-hypofractionated radiation in higher-risk prostate cancer

PURPOSEThis study evaluated outcomes associated with a high-dose-rate (HDR) brachytherapy boost combined with stereotactic body radiation therapy (SBRT) for patients with higher-risk localized prostate cancer.MATERIALS AND METHODSWe identified 101 patients with National Comprehensive Cancer Network high-risk, unfavorable intermediate-risk, or favorable intermediate-risk with probable extra-prostatic extension treated with HDR brachytherapy (15 Gy x 1 fraction) followed by SBRT (5 Gy x 5 daily fractions to the prostate and/or seminal vesicles and/or pelvic lymph nodes). Androgen deprivation therapy was used in 55.4% of all patients (90% of high-risk, 33% of intermediate-risk). Toxicities according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0 and International Prostate Symptom Scores were prospectively documented at each followup visit. Biochemical relapse was defined as PSA nadir +2ng/mL.RESULTSThe median follow-up time after SBRT was 24.1 months. No grade ≥3 toxicities were observed. The incidence of acute and late grade 2 gastrointestinal toxicities was both 0.99%. Acute and late grade 2 genitourinary (GU) toxicities were observed in 5.9% and 9.9%, respectively. Median time to a grade 2 GU toxicity was 6 months with a 14% 2-year actuarial rate of grade 2 GU toxicity. Median International Prostate Symptom Scores at 24 months was not significantly different than baseline (6 vs. 5; p = 0.24). Inclusion of pelvic lymph nodes and absence of a rectal spacer were significantly associated with more frequent grade ≥1 GU toxicity, but not grade ≥2 GU or gastrointestinal toxicity. The 2-year biochemical relapse free survival was 97%.CONCLUSIONSHDR brachytherapy combined with SBRT was associated with a favorable early toxicity profile and encouraging cancer control outcomes.     

Early toxicity and health-related quality of life results of high-dose-rate brachytherapy as monotherapy for low and intermediate-risk prostate cancer

PurposeTo determine the acute toxicity and effect on health-related quality of life of a two-fraction regimen of high-dose-rate (HDR) prostate brachytherapy.Methods and materialsPatients with low- or intermediate-risk prostate cancer were treated with HDR brachytherapy as monotherapy in two implants of 13.5 Gy spaced 7–14 days apart. Patients completed International Prostate Symptom Score (IPSS) and Expanded Prostate Index Composite (EPIC) questionnaires at 1, 3, 6, 9, 12, 16, 20, and 24 months after brachytherapy. Proportion of patients in each IPSS category (mild = 0–7, moderate = 8–18, severe = 19+) was evaluated at each of the intervals above. Paired t tests with baseline values were done for IPSS and EPIC scores.ResultsThirty patients were accrued to the study. Median prostate-specific antigen was 8,7 (range 4.1–17.5). T stages were T1c = 65%, T2a = 21%, and T2b = 14%. Twenty-seven percent of patients had a Gleason score of 6 and 73% had a Gleason score of 7. IPSS categories at baseline, 1, 3, 6, 12, and 24 months were mild (81%, 43%, 58%, 62%, 76%, 64%), moderate (19%, 32%, 29%, 30%, 20%, 29%), and severe (0%, 25%, 13%, 7%, 4%, 6%), respectively. There was a significant decrease in EPIC sexual summary scores at 1, 3, 6, and 12 months of 0 points (p < 0.001), 17 points (p = 0.01), 18 points (p = 0.02), and 17 points (p = 0.01), respectively.ConclusionsThis is the first report of this cohort of patients treated with two-fraction HDR monotherapy. This regimen shows rates of toxicity and health-related quality of life that appear acceptable as compared to other treatment modalities. These results are also comparable with other reports with similar treatment regimens.     

Sector analysis of dosimetry of prostate cancer patients treated with low-dose-rate brachytherapy

PurposeBrachytherapy is an effective single treatment modality for low- and intermediate-risk prostate cancer. Here, we compare the radiation doses in different prostate sectors between the preimplant planning images and the postimplant dosimetry.Methods and MaterialsTwo hundred fifteen consecutive patients treated for prostate cancer by ¹²⁵I seed brachytherapy were assessed. Pretreatment plans using transrectal ultrasound images of the prostate were compared with the dose calculated on posttreatment MRI and CT scans obtained 1 month after seed implantation. Twelve sectors were generated by dividing the prostate base, midgland, and apex into four quadrants each. Pretreatment and posttreatment dosimetry were compared between the 12 different sectors of the prostate.ResultsAverage V₁₀₀ (percentage of prostate volume that receives 100% of the prescribed dose) in the preimplant planning images of the prostate was 99.9 ± 0.25% compared with postimplant V₁₀₀ of 94.8 ± 3.77% (p < 0.0001). Prostate V₁₀₀ in the postimplant dosimetry was >91% in all sectors, except the anterior base sector, in which it was 64.87 ± 20.96%. Average 1-month D₉₀ (the dose to 90% of the prostate volume) was 114.5 ± 10.55%. D₉₀ at 1 month compared with preimplant planning was lower in the prostate base and higher in the prostate apex (p < 0.001).ConclusionsOur results show that in ¹²⁵I seed brachytherapy, prostate base receives a lower dose and apex receives a higher dose compared with preimplant planned dose coverage.     

Improved rectal dosimetry with the use of SpaceOAR during high-dose-rate brachytherapy

PurposeHydrogel spacers have been suggested to limit rectal radiation dose with improvements in clinical outcomes in patients undergoing external beam radiation treatment for prostate cancer. No studies to date have assessed the utility and dosimetric effect of SpaceOAR (Augmenix, Inc, Waltham, MA), the only Food and Drug Administration–approved hydrogel rectal spacer, for high-dose-rate (HDR) brachytherapy.MethodsEighteen consecutive patients scheduled for HDR brachytherapy in the treatment of prostate cancer underwent transperineal ultrasound-guided placement of 10 cc of SpaceOAR hydrogel following catheter implantation. Treatment plans were generated using an inverse planning simulated annealing algorithm. Rectal dosimetry for these 18 patients was compared with the 36 preceding patients treated with HDR brachytherapy without SpaceOAR.ResultsFifty-four plans were analyzed. There was no difference in age, pretreatment prostate-specific antigen, Gleason score, clinical stage, prostate volume, or contoured rectal volume between those who received SpaceOAR and those who did not. Patients who received SpaceOAR hydrogel had significantly lower dose to the rectum as measured by percent of contoured organ at risk (median, V₈₀ < 0.005% vs. 0.010%, p = 0.003; V₇₅ < 0.005% vs. 0.14%, p < 0.0005; V₇₀ 0.09% vs. 0.88%, p < 0.0005; V₆₀ = 1.16% vs. 3.08%, p < 0.0005); similar results were seen for rectal volume in cubic centimeters. One patient who received SpaceOAR developed a perineal abscess 1 month after treatment.ConclusionsTransperineal insertion of SpaceOAR hydrogel at the time of HDR brachytherapy is feasible and decreases rectal radiation dose. Further investigation is needed to assess the clinical impact of this dosimetric improvement and potential toxicity reduction.     

Risk factors for biochemical recurrence after a tissue-ablative prostate-specific antigen <0.2 ng/mL

PurposeA prostate-specific antigen (PSA) nadir <0.2 ng/mL is generally considered as tissue ablative and at low risk for recurrence. After attaining such a low PSA nadir, we analyzed risk factors for recurrence.Methods and materialsWe identified patients from our institutionalized database with either D'Amico low- or intermediate-risk prostate cancer that was treated with either low-dose-rate prostate brachytherapy or external beam radiotherapy as monotherapy. We compared patients who attained a nadir <0.2 ng/mL and subsequently developed biochemical failure to patients who did not experience biochemical failure by using χ² test and Student t test. Survival analysis was performed using the Kaplan–Meier method (log-rank test).ResultsOf 892 patients, 560 (63%) achieved a nadir <0.2 ng/mL. Only 23 (4.1%) later developed a biochemical recurrence. The 7-year Kaplan–Meier biochemical recurrence-free survival after a PSA nadir of <0.2 ng/mL was 96%. Patients who later experienced biochemical recurrence were more likely to have Cancer of the Prostate Risk Assessment Score intermediate- or high-risk cancer: (74% vs. 40%, p < 0.001). Patients were more likely to have a diagnostic PSA >6.0 ng/mL: (66% vs. 43% p < 0.001) and have a Gleason score ≥ 3  + 4: (52% vs. 34%, p = 0.005). They were also more likely to be older (p = 0.003): mean (SD) 70.3 (6.4) vs. 66.2 (6.5) and have a time to PSA nadir that was significantly shorter (p = 0.013): mean (SD) 51.8 (29.6) vs. 65.2 (25.1).ConclusionsBiochemical recurrence after attaining a PSA nadir <0.2 ng/mL is rare and more frequent in patients with intermediate risk cancer and older patients. These patients can benefit from a prolonged followup with specialized physicians.     

Biochemical outcomes and predictive factors by risk group after permanent iodine-125 seed implantation: Prospective cohort study in 2,316 patients

PurposeTo evaluate the biochemical freedom from failure (bFFF) by risk group and treatment modality and the predictive factors of bFFF by risk group in patients with prostate cancer undergoing permanent seed implantation (PI) with or without external beam radiation therapy (EBRT) in a nationwide prospective cohort study (Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 [I-125] Seed Implantation) in Japan during the first 2 years.Methods and MaterialsThe analyses included 2,316 participants in 42 institutions; bFFF was evaluated using the Phoenix definition and calculated using the Kaplan–Meier method, and the Cox proportional hazards model was used to identify the factors associated with bFFF.ResultsMedian followup period was 60.0 months. The 5-year bFFF rates in all patients, 1,028 low-risk patients, 1,114 intermediate-risk patients, and 133 high-risk patients were 93.6%, 94.9%, 92.7%, and 91.1%, respectively. The 5-year bFFF rates in the PI group and EBRT combination therapy group were 93.7% and 93.3%, respectively. In a multivariate analysis, younger age, higher Gleason score (GS), higher percent positive biopsies (%PB), and lower prostate V₁₀₀ (p = 0.0012, 0.0030, 0.0026, and 0.0368) in all patients; younger age, higher pretreatment prostate-specific antigen, and lower prostate V₁₀₀ (p = 0.0002, 0.0048, and 0.0012) in low-risk patients; higher GS, higher %PB, and no hormonal treatment (p = 0.0005, 0.0120, and 0.0022) in intermediate-risk patients; and higher GS and higher %PB (p = 0.0329 and 0.0120) in high-risk patients were significantly associated with bFFF.ConclusionsPI with or without EBRT resulted in excellent short-term biochemical outcomes in all risk groups, especially in high-risk patients. Age, pretreatment prostate-specific antigen, and prostate V₁₀₀ in low-risk patients; GS, %PB, and hormonal treatment in intermediate-risk patients; and GS and %PB in high-risk patients were independently affected bFFF.     

Brachytherapy provides comparable outcomes and improved cost-effectiveness in the treatment of low/intermediate prostate cancer

PurposeTo evaluate the cost-effectiveness and outcomes of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy compared with intensity-modulated radiation therapy (IMRT) in patients with low/intermediate risk of prostate cancer.Methods and MaterialsOne thousand three hundred twenty-eight patients with low or intermediate risk of prostate cancer were treated with LDR (n = 207), HDR with four fractions (n = 252), or IMRT (n = 869) between January 1992 and December 2008. LDR patients were treated with palladium seeds to a median dose of 120 Gy, whereas HDR patients were treated to a median dose 38.0 Gy (four fractions). IMRT patients received 42–44 fractions with a median dose of 75.6 Gy. Clinical outcomes were compared, including biochemical failure, cause-specific survival, and overall survival.ResultsOverall, no differences in 5-year biochemical control (BC) or cause-specific survival were noted among treatment modalities. The calculated reimbursement for LDR brachytherapy, HDR brachytherapy with four fractions, and IMRT was $9,938; $17,514; and $29,356, respectively. HDR and LDR brachytherapy were statistically less costly to Medicare and the institution than IMRT (p < 0.001), and LDR brachytherapy was less costly than HDR brachytherapy (p = 0.01 and p < 0.001). Incremental cost-effectiveness ratios for cost to Medicare for BC with IMRT were $4045 and $2754 per percent of BC for LDR and HDR brachytherapy, respectively. Incremental cost-effectiveness ratio using institutional cost comparing IMRT with LDR and HDR brachytherapy was $4962 and $4824 per 1% improvement in BC.ConclusionsIn this study of patients with low and intermediate risk of prostate cancer, comparable outcomes at 5 years were noted between modalities with increased costs associated with IMRT.     

Cesium-131 prostate brachytherapy: A single institutional long-term experience

AimsTo report on the PSA outcomes in men undergoing prostate seed implant (PSI) with Cesium-131 at a single institution.Materials and MethodsAll patients who underwent prostate brachytherapy with Cesium-131 (¹³¹Cs) at our institution and had the potential for at least 24 months of follow up were included in this study. Results are reported for the by NCCN risk group (low, low/high-intermediate, and high), as well as by treatment received (monotherapy, combination external beam radiation + PSI, or trimodal therapy with androgen deprivation). The Phoenix definition (absolute nadir plus 2 ng/mL) was used to define biochemical freedom from disease (BFD).ResultsEight hundred and six men have undergone prostate brachytherapy with Cesium-131 at our institution, and 669 men were included in analysis. Median follow up was 60.0 months (range: 0–144 months). According to NCCN risk categories, 29.9% were low-, 55.6% intermediate-, and 14.5% high-risk. Using the Phoenix criteria, 5/10-year BFD was 97.1/95.3% for patients in the low-risk category, 94.0/90.1% for patients in the intermediate-risk category, and 86.2/56.6% for patients in the high-risk category. PSA ≤0.2 ng/dL at 4 years was predictive of 10 year biochemical control: 96.3% vs 70.4%, p < 0.001.ConclusionsThe present study demonstrates that prostate brachytherapy with ¹³¹Cs achieves excellent long-term biochemical control.     

Clinical outcomes of high-dose-rate brachytherapy and external beam radiotherapy in the management of clinically localized prostate cancer

PurposeTo report prostate-specific antigen (PSA) relapse-free survival and treatment-related toxicity outcomes after combining high-dose-rate (HDR) brachytherapy with external beam radiotherapy (EBRT) for patients with clinically localized prostate cancer.Methods and MaterialsBetween 1998 and 2009, 229 patients were treated with HDR brachytherapy followed 3 weeks later by supplemental EBRT. The HDR brachytherapy boost consisted of three fractions of ¹⁹²Ir (5.5–7.5 Gy per fraction), and EBRT consisted of intensity-modulated radiotherapy delivering an additional 45.0–50.4 Gy directed to the prostate gland and seminal vesicles. Median follow-up was 61 months.ResultsSeven-year PSA relapse-free survival for low-, intermediate-, and high-risk patients were 95%, 90%, and 57%, respectively (p < 0.001). Among high-risk patients treated with biological equivalent doses in excess of 190 Gy, 7-year PSA relapse-free survival was 81%. In multivariate analysis, Gleason scores of ≥8 predicted for increased risk of biochemical failure, whereas the use of short-term neoadjuvant androgen deprivation therapy did not influence tumor-control outcomes even among intermediate- or high-risk patients. Seven-year incidence of distant metastases for low-, intermediate-, and high-risk patients were 5%, 3%, and 17%, respectively. Seven-year incidence of late Grade 2 and 3 genitourinary toxicities were 22.1% and 4.9%, respectively and the 7-year incidence of Grade 2 and 3 gastrointestinal toxicities were 1% and 0.4%, respectively.ConclusionHDR prostate brachytherapy in conjunction with supplemental EBRT results in excellent biochemical relapse-free survival rates with a low incidence of severe late genitourinary or gastrointestinal toxicities. The use of short-term neoadjuvant androgen deprivation did not influence long-term biochemical tumor control in this cohort.     

Focal brachytherapy for selected low-risk prostate cancers: A pilot study

PurposeTo evaluate the feasibility and the early toxicity of focal brachytherapy in highly selected localized prostate cancer patients.Methods and MaterialsTwenty-one patients underwent a focal brachytherapy between February 2010 and March 2012, representing 3.7% of the cases treated by our group during this period. Patient selection was based on (at least) two series of prostate biopsies and a high-resolution MRI. Only patients with very limited and localized tumors, according to strict criteria, were selected for the procedure. The technique used a real-time procedure with the implantation of free ¹²⁵I seeds and dynamic dose calculation. The prescribed dose for the focal volume was 145 Gy.ResultsThe treated volume corresponded to a mean value of 34% of the total prostatic volume (range, 20–48%). For the focal volume, the mean D₉₀ and V₁₀₀ was 183.2 Gy (range, 176–188 Gy) and 99.3% (range, 98.8–100%), respectively. The technique was performed in an hour and a half. When compared with a previous cohort treated by whole-prostate brachytherapy, urinary toxicity (International Prostate Symptom Score) was borderline reduced (p = 0.04) at 6 months only, whereas the recovery of the International Index of Erectile Function 5 was better (p = 0.014). The International Continence Score was nil in almost all cases as well as rectal toxicity.ConclusionFocal treatment by brachytherapy is easily feasible with little acute toxicity. Further investigation is needed to assess the results in terms of tumor control and long-term toxicity.