A Medicare cost analysis of MRI- versus CT-based high-dose-rate brachytherapy of the cervix: Can MRI-based planning be less costly?

PurposeWhile some institutions deliver multiple fractions per implant for MRI-based planning, it is common for only one fraction to be delivered per implant with CT-based cervical brachytherapy. The purpose of this study was to compare physician costs, hospital costs, and overall costs for cervical cancer patients treated with either CT-based or MRI-based high-dose-rate (HDR) cervical brachytherapy to determine if MRI-based brachytherapy as described can be financially feasible.Methods and MaterialsWe identified 40 consecutive patients treated with curative intent cervical brachytherapy. Twenty patients underwent CT-based HDR brachytherapy with five fractions delivered in five implants on nonconsecutive days in an outpatient setting with the first implant placed with a Smit sleeve under general anesthesia. Twenty patients received MRI-based HDR brachytherapy with four fractions delivered in two implants, each with MRI-based planning, performed 1–2 weeks apart with an overnight hospital admission for each implant. We used Medicare reimbursements to assess physician costs, hospital costs, and overall cost.ResultsThe median cost of MRI-based brachytherapy was $14,248.75 (interquartile range [IQR]: $13,421.32–$15,539.74), making it less costly than CT-based brachytherapy with conscious sedation (i.e., $18,278.85; IQR: $17,323.13–$19,863.03, p < 0.0001) and CT-based brachytherapy with deep sedation induced by an anesthesiologist (i.e., $27,673.44; IQR: $26,935.14–$29,511.16, p < 0.0001). CT-based brachytherapy with conscious sedation was more costly than CT-based brachytherapy with deep sedation (p < 0.001).ConclusionsMRI-based brachytherapy using the described treatment course was less costly than both methods of CT-based brachytherapy. Cost does not need to be a barrier for MRI-based cervical brachytherapy, especially when delivering multiple fractions with the same application.     

A phase IB clinical trial of 15 Gy HDR brachytherapy followed by hypofractionated/SBRT in the management of intermediate-risk prostate cancer

PurposeHigh dose-rate (HDR) brachytherapy is commonly administered as a boost to external beam radiation therapy (EBRT). Our purpose was to compare toxicity with increasingly hypofractionated EBRT in combination with a single 15 Gy HDR boost for men with intermediate-risk prostate cancer.Methods and MaterialsForty-two men were enrolled on this phase IB clinical trial to one of three EBRT dose cohorts: 10 fractions, seven fractions, or five fractions. Patients were followed prospectively for safety, efficacy, and health-related quality of life (Expanded Prostate Index Composite). Efficacy was assessed biochemically using the Phoenix definition.ResultsWith a median follow up of 36 months, the biochemical disease-free survival was 95.5%. One man developed metastatic disease at 5 years. There was no significant minimally important difference in EPIC PRO for either urinary, bowel, or sexual domains. There was one acute Grade 3 GI and GU toxicity, but no late Grade 3 GU or GI toxicities.ConclusionFifteen gray HDR brachytherapy followed by a five fraction SBRT approach results in high disease control rates and low toxicity similar to previously reported HDR protocols with significant improvement in patient convenience and resource savings. While mature results with longer follow up are awaited, this treatment approach may be considered a safe and effective option for men with intermediate-risk disease.     

Patient-reported outcomes after Low-dose-rate versus High-dose-rate brachytherapy boost in combination with external beam radiation for intermediate and high risk prostate cancer

PURPOSEAddition of a brachytherapy boost to external beam radiation therapy (EBRT) reduces prostate cancer (PCa) recurrence at the expense of genitourinary (GU) toxicity. Whether brachytherapy boost technique, specifically low-dose-rate (LDR-BT) versus high-dose-rate (HDR-BT), impacts treatment-related toxicity is unclear.METHODSBetween 2012-2018, 106 men with intermediate/high risk PCa underwent EBRT (37.5-45 Gy in 1.8-2.5 Gy/fraction) plus brachytherapy boost, either with LDR-BT (110 Gy I-125 or 100 Gy Pd-103; n = 51) or HDR-BT (15 Gy x1 Ir-192; n = 55). Patient-reported outcomes (PRO) were assessed by International Prostate Symptom Score (IPSS) and Expanded Prostate Cancer Index Composite (EPIC-CP) surveys at 3-6-month intervals for up to three years following treatment, with higher scores indicating more severe toxicity. Provider-reported GU and gastrointestinal (GI) toxicity was graded per CTCAE v5.0 at each follow-up. Linear mixed models comparing PROs between LDR-BT versus HDR-BT were fitted. Stepwise multivariable analysis (MVA) was performed to account for age, gland size, androgen deprivation therapy use, and alpha-blocker medication use. Incidence rates of grade 2+ GU/GI toxicity was compared using Fisher's exact test.RESULTSUse of LDR-BT was associated with greater change in IPSS (p=0.003) and EPIC-CP urinary irritative score (p = 0.002) compared with HDR-BT, but effect size diminished over time (LDR-BT versus HDR-BT: baseline to 6-/24-month mean IPSS change, +6.4/+1.4 versus +2.7/-3.0, respectively; mean EPIC-CP irritative/obstructive change, +2.5/+0.1 versus +0.9/+0.1, respectively). Results remained significant on MVA. Post-treatment grade 2+ GU toxicity was significantly higher in the LDR-BT group (67.5% versus 42.9% for LDR-BT and HDR-BT, respectively; p <0.001). There were no differences between groups in incontinence, bowel function, and erectile function, or grade 2+ GI toxicity.CONCLUSIONCompared with LDR-BT, HDR-BT was associated with lower acute patient- and provider-reported GU toxicity.     

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.     

Comparison of computed tomography with magnetic resonance imaging for imaging-based clinical target volume contours in cervical cancer brachytherapy

PurposeTo compare CT- and MRI-based brachytherapy (BT) target volumes for patients with advanced cervical cancer so as to identify those who benefit most from MRI-based planning. We also studied how the natural mobility of the organ at risks (OARs) affects the given doses.Methods and MaterialsSubjects were 60 patients with International Federation of Gynecology and Obstetrics (FIGO) Stage IB–IVA cervical cancer. The CT high-risk clinical target volume (HR-CTV) was first delineated, then the MRI HR-CTV, with volume discrepancies calculated by subtraction. The DICE coefficient (DC) of similarity was calculated from a superimposition of the volumes. Maximum doses delivered to D_2cc of OARs in CT and MRI plans were compared; the effect of time on the natural mobility was analyzed.ResultsThe mean HR-CTVs and the maximum doses given to OARs in CT- and MRI-based planes were similar. Multivariate analysis showed that deep infiltration affecting the uterine corpus and bowel loops adjacent to the cervix were the factors significantly impacting on the volume discrepancy between CT and MRI HR-CTV (p = 0.001, p = 0.045) and on the DC (p = 0.005, p = 0.028). Univariate analysis demonstrated that the FIGO stage had a significant impact on DC (p = 0.022). Patients with bowel loops adjacent to the cervix had lower body mass indices (p = 0.003). The median difference between the doses given in CT- and MRI-based plans, caused by mobility, were 0.5 Gy, 0.3 Gy, and 0.45 Gy per fraction for the rectum, bladder and sigmoid, respectively. No correlation of observed uncertainties and time between image acquisitions was detected.ConclusionsCT- or MRI-based scans at BT are adequate for OAR dose–volume histograms analysis. Cervical cancer patients with deep infiltration affecting the uterine corpus, a low body mass index with bowel loops adjacent to the cervix and an FIGO Stage III–IVA benefit most from MRI-based planning of BT.     

Impact of MRI-based postimplant dosimetric assessment in prostate brachytherapy using contrast-enhanced T1-weighted images

PurposeTo compare contrast-enhanced T1-weighted (CE-T1WI) magnetic resonance imaging (MRI) with computed tomography (CT) for postimplant dosimetry and seed recognition in prostate brachytherapy.Methods and MaterialsA total of 245 patients who received ¹²⁵I prostate brachytherapy with or without external beam radiotherapy were enrolled. For postimplant analysis, CT and MRI scans were obtained at 1 month after seed implantation. For MRI-based dosimetry, T2-weighted images were fused with the CE-T1WI; the prostate was delineated on the T2-weighted images, and the seed detection was performed manually on the CE-T1WI. In CT-based dosimetry, the seed detection was essentially performed automatically. The dosimetric results obtained by MRI-based and CT-based dosimetry were compared.ResultsThe mean prostate D₉₀ (the minimum dose received by 90% of the prostate volume) estimated by MRI-based and CT-based dosimetry were 113% and 115%, respectively, with no significant difference. The mean prostate V₁₀₀ (the percent volume of the postimplant prostate receiving 100% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 95.2% and 95.8%, respectively, again with no significant difference. The mean prostate V₁₅₀ (the percent volume of the postimplant prostate receiving 150% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 52.8% and 57.0%, respectively (p < 0.01). In all of the 35 patients (14%) in whom the MRI-based V₁₅₀ were at least 10% lower than the CT-based results, the seed detection by CT-based dosimetry was overestimated in highly seed-clustered areas or in the areas close to calcifications because of reconstruction artifacts in CT images.ConclusionsMRI-based dosimetry using CE-T1WI appears to be acceptable. Our results suggest that MRI-based dosimetry is a practical method for estimation of the higher dose distribution, especially if seeds are clustered together or when they are close to calcifications.     

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.     

Change in image-guided planning strategies over time impacts oncologic and survival outcomes for intracavitary cervical cancer brachytherapy

PURPOSEIntracavitary cervical brachytherapy (BT) has transitioned from a two-dimensional nonvolumetric (NV) dosimetry system to three-dimensional computed tomography (CT) and/or magnetic resonance imaging (MRI)-based planning techniques. The purpose of this study is to retrospectively evaluate the relative improvements in image-guided planning strategies over time with regards to dosimetry, survival, and toxicity.METHODS AND MATERIALSA single site retrospective review of 95 locally advanced cervical cancer patients treated with concurrent chemoradiation and high dose rate BT from 2009 to 2016 were divided into three BT planning groups: point-A based NV dosimetry using CT imaging (n = 37), CT-based volumetric dosimetry (n = 33), and MRI-based volumetric dosimetry (n = 25). Overall survival (OS), progression free survival (PFS), and pelvic control (PC) at 5 years were plotted using Kaplan–Meier curves. Univariate and multivariate (MVA) cox proportional-hazards models calculated hazard-ratios (HZ). Finally, acute and late grade 3–4 toxicities were compared between the cohorts.RESULTSBoth MRI and CT had significantly less D2cc to bowel (p < 0.001) and sigmoid (p < 0.001) compared to NV-based planning. On MVA, age (<60 vs. ≥60 years) was significant for worse 5-year OS (HZ: 2.48) and PC (HZ: 5.25). MRI, with NV as the reference, had significantly improved 5-year OS (HZ: 0.26), PFS (HZ: 0.34) and PC (HZ: 0.16). There was no significant difference in grade ≥3 toxicities between the cohorts.CONCLUSIONSCT and MRI-based 3D planning had significantly less D2cc to bowel and sigmoid. MRI-based planning had significant improvement in 5-year OS, PFS, and LC compared to NV on MVA.     

Toxicity and early treatment outcomes in low- and intermediate-risk prostate cancer managed by high-dose-rate brachytherapy as a monotherapy

PurposeTo determine the acute and late genitourinary (GU) and gastrointestinal (GI) toxicity and present short-term biochemical no evidence of disease (bNED) rates after high-dose-rate brachytherapy (HDR-B) monotherapy.Methods and MaterialsBetween October 2003 and June 2006, 36 patients with low (28) and intermediate (8) risk prostate cancer (PCA) were treated by HDR-B monotherapy. All patients received one implant and four fractions of 9.5 Gy within 48 h for a total prescribed dose (PD) of 38 Gy. Five patients received hormonal therapy (HT). Median age was 63.5 years and median followup was 3 years (range, 0.4–4 years). Toxicity was scored according to the CTCAE version 3.0. Biochemical failure was defined according to the Phoenix criteria.ResultsAcute and late Grade 3 GU toxicity was observed in 1 (3%) and 4 (11%) patients, respectively. Grade 3 GI toxicity was absent. The three- year bNED survival rate was 100%. The sexual preservation rate in patients without HT was 75%. Late Grade 3 GU toxicity was associated with the planning target volume (PTV) V₁₀₀ (% PTV receiving ≥100% of the PD; p = 0.036), D₉₀ (dose delivered to 90% of the PTV; p = 0.02), and the urethral V₁₂₀ (urethral volume receiving ≥120% of the PD; p = 0.043). The urethral V₁₂₀ was associated with increased PTV V₁₀₀ (p < 0.001) and D₉₀ (p = 0.003).ConclusionsAfter HDR-B monotherapy, late Grade 3 GU toxicity is associated with the urethral V₁₂₀ and the V₁₀₀ and D₉₀ of the PTV. Decrease of the irradiated urethral volume may reduce the GU toxicity and potentially improve the therapeutic ratio of this treatment.     

Impact on treatment time of MRI-based brachytherapy in two implants (4 doses) compared with CT-based brachytherapy in five implants for cervical cancer

Purpose

Concurrent chemoradiotherapy and brachytherapy is the standard of care for locally advanced cervical cancer. Brachytherapy is an integral part of treatment and has improved overall survival. Research is needed to ascertain the planning modalities and schedules to best use resources and optimize treatment time course. We hypothesized that MRI-based brachytherapy when delivered with the described regimen would not prolong, and potentially shorten, overall treatment time as compared with CT-based brachytherapy.

The equivalent dose contribution from high-dose-rate brachytherapy to positive pelvic lymph nodes in locally advanced cervical cancer

PurposeDefinitive radiation therapy for locally advanced cervical cancer involves external beam radiation therapy (EBRT) and high-dose-rate (HDR) brachytherapy. There remains controversy and practice pattern variation regarding the optimal radiation dose to metastatic pelvic lymph nodes (LNs). This study investigates the contribution of the pelvic LN dose from HDR brachytherapy.Methods and MaterialsFor 17 patients with 36 positive pelvic LNs, each LN was contoured on a computed tomography (CT) plan for EBRT and on brachytherapy planning CTs using positron emission tomographic images obtained before chemoradiation. The mean delivered dose from each plan was recorded, and an equivalent dose in 2-Gy fractions (EQD2) was calculated. A Student's t test was performed to determine if the mean delivered dose is significantly different from the mean prescribed dose and EQD2.ResultsThe average prescribed dose from the total EBRT was 54.09 Gy. The average prescribed HDR dose to International Commission on Radiation Units point A was 26.81 Gy. The average doses delivered to the involved LNs from EBRT and brachytherapy were 54.25 and 4.31 Gy, respectively, with the corresponding EQD2 of 53.45 and 4.00 Gy. There was no statistically significant difference (p < 0.05) between the mean delivered and the prescribed doses for EBRT and between the delivered dose and the EQD2 for EBRT and brachytherapy.ConclusionsOur study shows that the HDR contribution is 7% (4.00 Gy) of the total EQD2 (57.45 Gy). The HDR contribution should be accounted for when prescribing the EBRT boost dose to pelvic LNs for the optimal therapeutic dose.     

Patient-reported quality of life after salvage brachytherapy for radio-recurrent prostate cancer: A prospective Phase II study

BackgroundPatient-reported quality of life (QOL) after salvage brachytherapy for radiorecurrent prostate cancer has not been well-characterized prospectively.MethodsWe examined 25 men who recurred after primary radiotherapy for prostate cancer and received MRI-guided salvage brachytherapy as part of a prospective Phase II study. These patients received prospectively a validated patient-reported QOL questionnaire to fill out at baseline, as well as 3, 15, and 27 months after re-irradiation to determine the degree of sexual, bowel, and urinary dysfunction (maximum dysfunction score = 100).ResultsOn average, sexual function continued to decline with time, and patients had significantly worse sexual function scores at 27 months than baseline (p = 0.01). Although bowel and urinary symptoms worsened acutely at 3 or 15 months, they showed on average some improvement by 27 months, and there were no significant differences between baseline and 27-month urinary or bowel scores. An interval to re-irradiation less than 4.5 years and prior brachytherapy were each associated significantly with the largest decrements in bowel function (p = 0.035).ConclusionSimilar to the patterns seen in the de novo setting, patients who receive salvage brachytherapy report a worsening of bowel and urinary symptoms followed by some improvement by 27 months, while sexual function steadily declines over time. Interval to re-irradiation and type of prior radiation received may be used to counsel and optimize selection of men for salvage brachytherapy with regard to QOL endpoints.     

High-dose-rate interstitial brachytherapy as monotherapy in one fraction and transperineal hyaluronic acid injection into the perirectal fat for the treatment of favorable stage prostate cancer: treatment description and preliminary results

PurposeTo evaluate the technical feasibility, acute and late genitourinary (GU) toxicity, and gastrointestinal toxicity after high-dose-rate (HDR) brachytherapy as monotherapy in one fraction with transperineal hyaluronic acid injection into the perirectal fat to displace the rectal wall away from the radiation sources to decrease rectal toxicity.Methods and MaterialsBetween April 2008 and January 2010, 40 consecutive patients were treated with favorable clinically localized prostate cancer; the median followup was 19 months (range, 8–32). No patients received external beam radiation, and 35% received hormone therapy before brachytherapy. All patients received one implant and one fraction of HDR. Fraction dose was 19 Gy. Toxicity was reported according to the Common Toxicity Criteria for Adverse Event, Version 4.0.ResultsAll patients tolerated the implantation procedure very well with minimal discomfort. No intraoperative or perioperative complications occurred. Acute toxicity Grade 2 or more was not observed in any patients. No chronic toxicity has been observed after treatment. Logistic regression showed that the late Grade 1 GU toxicity was associated with D₉₀ (p = 0.050). The 32-month actuarial biochemical control was 100% and 88%, respectively (p = 0.06) for low- and intermediate-risk groups.ConclusionsThis is the first published report of the use of HDR brachytherapy as monotherapy in one fraction for patients with favorable-risk prostate cancer. This protocol is feasible and very well tolerated with low GU morbidity, no gastrointestinal toxicity, and the same level of low-dose-rate biochemical control at 32 months.     

Dose to the dominant intraprostatic lesion using HDR vs. LDR monotherapy: A Phase II randomized trial

PurposeTo present the dosimetric results of a Phase II randomized trial comparing dose escalation to the MRI-defined dominant intraprostatic lesion (DIL) using either low-dose-rate (LDR) or high-dose-rate (HDR) prostate brachytherapy.Material and MethodsPatients receiving prostate brachytherapy as monotherapy were randomized to LDR or HDR brachytherapy. Prostate and DILs were contoured on preoperative multiparametric MRI. These images were registered with transrectal ultrasound for treatment planning. LDR brachytherapy was preplanned using I-125 seeds. HDR brachytherapy used intraoperative transrectal ultrasound–based planning to deliver 27 Gy/2 fractions in separate implants. DIL location was classified as peripheral, central, or anterior. A student t-test compared DIL D₉₀ between modalities and DIL locations.ResultsOf 60 patients, 31 underwent LDR and 29 HDR brachytherapy. Up to three DILs were identified per patient (100 total) with 74 peripheral, six central, and 20 anterior DILs. Mean DIL volume was 1.9 cc (SD: 1.7 cc) for LDR and 1.6 cc (SD 1.3 cc) for HDR (p = 0.279). Mean DIL D₉₀ was 151% (SD 30%) for LDR and 132% (SD 13%) for HDR. For LDR, mean peripheral DIL D₉₀ was 159% (SD 27%) and central or anterior 127% (SD 13%). HDR peripheral DILs received 137% (SD 12%) and central or anterior 119% (SD 7%). DIL D₉₀ for peripheral lesions was higher than anterior and central (p < 0.001).ConclusionsDIL location affects dose escalation, particularly because of urethral proximity, such as for anterior and central DILs. HDR brachytherapy may dose escalate better when target DIL is close to critical organs.     

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.     

Postoperative management of keloids: Low-dose-rate and high-dose-rate brachytherapy

PurposeWe report the experience of the Radiation Oncology Department of the European Institute of Oncology in Milan, Italy, on the adjuvant low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy. Brachytherapy might be useful to improve keloids recurrence rate or reduce keloids treatment side effects instead of external beam radiotherapy.Methods and MaterialsData on 70 consecutive patients treated after complete keloid surgical excision were retrospectively analyzed. First 38 patients and 46 keloids were treated with adjuvant LDR brachytherapy and the following 39 patients and 50 keloids underwent HDR treatment. Median delivered dose of LDR therapy was 16 Gy; HDR median dose was 12 Gy. Sixty-four keloids (66.7%) were symptomatic at diagnosis with pain, itching, or stress.ResultsFourteen relapses over 46 treated keloids (30.4%) were observed in the LDR group and 19 of 50 keloids (38%) in the HDR group (p = 0.521). Recurrence rate was significantly higher in males (p = 0.009), in patients younger than 44 years (p < 0.0001), for arms, neck, and chest wall anatomic sites (p = 0.0001) and for symptomatic keloids (p = 0.017). Aesthetic outcome was better in case of larger keloids (>8 cm) (p = 0.064). Symptomatic relief was achieved in 92% of HDR patients and only 68% of LDR patients (p = 0.032).ConclusionsPostoperative brachytherapy is an effective treatment for keloids. In our study, LDR and HDR treatments resulted in similar recurrence rate. Better symptomatic relief was reported in case of HDR treatment compared with the LDR regimen.     

Comparison of clinical outcomes achieved with image-guided adaptive brachytherapy for cervix cancer using CT or transabdominal ultrasound

PurposeThis study aimed to evaluate retrospectively the treatment results when using various image-guided adaptive brachytherapy treatments for cervical cancer treated by radical radiotherapy.Methods and MaterialsFrom 2014 to 2017, 188 patients with cervical carcinoma were treated by whole pelvic radiotherapy plus four fractions of image-guided brachytherapy. Eight patients were excluded because of missing data. Consequently, 180 patients were analyzed. Of 180 patients, 92 were treated by CT-based brachytherapy (CT-BT), and transabdominal ultrasound–based brachytherapy (TAUS-BT) was used to treat another group. The treatment results and toxicity outcomes were evaluated by comparing the image-guidance techniques.ResultsThe mean follow-up time was 32 months (interquartile range 29.5–42 months). The mean age was 57 years (interquartile range from 50 to 65 years). In the CT-BT group, the mean cumulative doses to high-risk clinical target volume, bladder, rectum, and sigmoid were 87.2 Gy, 84.0 Gy, 68.8 Gy, and 69.8 Gy, respectively. In the TAUS-BT group, the mean cumulative doses to the cervix reference, bladder, and rectum points were 84.0 Gy, 65.5 Gy, and 74.0 Gy, respectively. There were no differences in the 2-year local control rate (p = 0.88) and disease-free survival rate (p = 0.34) in both groups. No difference in gastrointestinal and genitourinary toxicity was observed in both groups, but there was higher vaginal toxicity in the TAUS-BT group compared with the CT-BT group (p = 0.03).ConclusionsNo difference in treatment results was observed between CT-based and TAUS-based approaches. However, TAUS-BT had higher vaginal toxicity in our retrospective analysis.     

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.     

Concurrent chemoradiation for cervical cancer: Comparison of LDR and HDR brachytherapy

PurposeTo compare clinical outcomes between low-dose-rate (LDR) brachytherapy and high-dose-rate (HDR) brachytherapy for cervical cancer patients.Methods and MaterialsAll consecutive newly diagnosed cervical cancer patients undergoing pretreatment 18-fluorodeoxyglucose positron emission tomography imaging and treated with curative-intent definitive chemoradiation from 1997 to 2016 at a U.S. academic center were included. Brachytherapy boost was LDR or HDR 2D treatment planning from 1997 to 2005 and HDR with MR-based 3D planning from 2005 to 2016. Local control (LC), cancer-specific survival (CSS), and late bowel/bladder complications were evaluated.ResultsTumor stages were International Federation of Gynecology and Obstetrics IB1-IIB (n = 457; 75%) and III-IVA (n = 152; 25%). Brachytherapy was LDR for 104 patients and HDR for 505 patients. Concurrent weekly cisplatin was administered to 536 patients (88%). With median followup of 9.4 years, there was no difference in LC (p = 0.24) or CSS (p = 0.50) between LDR and HDR brachytherapy. Cox multivariable regression showed that only International Federation of Gynecology and Obstetrics stage III-IVA (HR=2.4, p = 0.004) was associated with worse LC. A propensity-matched cohort (90 LDR vs. 90 HDR) was created, and the 5-year LC rates were 88% LDR and 82% HDR, p = 0.26; 5-year CSS rates were 66% LDR and 58% HDR, p = 0.19; 5-year grade ≥3 bowel/bladder toxicities were 23% LDR and 16% HDR, p = 0.44. For all patients, the 5-year late toxicity in stage III-IVA patients was higher with LDR 47% vs. HDR 15%, p = 0.03, with no difference in LC, 86% and 75%, respectively (p = 0.09).ConclusionsThere was no difference in LC with either LDR or HDR brachytherapy. The late complication rate was reduced with HDR and 3D-planned brachytherapy compared to LDR and 2D-planned brachytherapy.