Brachytherapy Catheters Research Articles

Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors

Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.

SU‐C‐103‐05: Automated Interstitial Brachytherapy Catheter Localization From Volumetric MR Data

Purpose: This work seeks to validate an automatic method for extracting interstitial catheter locations from volumetric MR data. Methods: A 3D b‐SSFP (balanced Steady State Free Precession) MRI sequence was used to enhance catheter detection, utilizing a controlled enlargement of size caused by magnetic susceptibility artifacts . Starting with a user‐provided needle‐tip location, the needle extraction algorithm searched the MR image for segments that maximized the “needle likelihood” and iteratively fit Bezier curves to these segments. To validate the geometry of extracted catheters, a phantom was constructed from transparent gel wax. An obturator was placed at the center of a transparent plastic container, and wax gel was melted and poured around it. A Syed‐Neblett template was then placed at one end of the obturator and 12 MR compatible catheters were inserted into the gel. The catheter trajectories extracted from the MR scan by the algorithm were compared to a CT scan. The algorithm was applied to patient scans under an IRB approved protocol. Results: The volumetric b‐SSFP sequence produced an artifact enhancement that enabled brachytherapy catheters to be distinguished from other signal voids. Comparison in a phantom of catheter locations extracted automatically from MR to those extracted manually from CT showed agreement of 3.5 mm Hausdorff Distance. When applied to patient scans, the presence of low signal regions between template and the target tumor required some manual intervention to ensure proper catheter extraction. Conclusion: An automatic algorithm for extracting interstitial catheter locations from MR scans has been developed. Using a b‐SSFP sequence allowed an iterative curve fitting algorithm to track MR artifacts from user provided tips to template. This algorithm should prove helpful to facilitate MR based treatment planning for interstitial brachytherapy. NIH P41 EB015898

Locoregional Recurrence Following Accelerated Partial Breast Irradiation for Early-Stage Invasive Breast Cancer: Significance of Estrogen Receptor Status and Other Pathological Variables

Understanding risk factors for locoregional recurrence (LRR) after accelerated partial breast irradiation (APBI) can help to guide patient selection for treatment with APBI. Published findings to date have not been consistent. More data are needed as these risk factors continue to be defined. A total of 277 women with early-stage invasive breast cancer underwent lumpectomy and were treated adjuvantly at our institution with APBI using high-dose rate brachytherapy. APBI was delivered using multicatheter interstitial brachytherapy (91%) or single-entry catheter brachytherapy (9%) to a dose of 32-34Gy in 8-10 twice daily fractions. Failure patterns and risk factors for recurrence were analyzed. With a median follow-up of 61months, the 5-year locoregional control rate was 94.4%. Negative estrogen receptor (ER) status was strongly associated with LRR on multivariate analysis (p<0.005). Lobular histology, the presence of an extensive intraductal component, and lymphovascular invasion also were significant but to a lesser degree than ER-negative status. Patients with multiple risk factors were at highest risk for LRR. Age was not significantly associated with increased risk for LRR. The presence of specific pathological features, particularly ER negative status, was associated with increased risk of LRR in this cohort of women treated with APBI. Further investigation is warranted to determine whether patients with adverse pathological risk factors are at higher risk of LRR after APBI than after conventional whole breast irradiation (WBI), as these same features also may place women at risk for LRR after WBI.

PD-0034: Feasibility of using multiparametric MRI to study the effect of brachytherapy catheter insertion into the prostate

PD-0034: Feasibility of using multiparametric MRI to study the effect of brachytherapy catheter insertion into the prostate

Contura Multi-Lumen Balloon Breast Brachytherapy Catheter: Comparative Dosimetric Findings of a Phase 4 Trial

Final dosimetric findings of a completed, multi-institutional phase 4 registry trial using the Contura Multi-Lumen Balloon (MLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer are presented. Three dosimetric plans with identical target coverage were generated for each patient for comparison: multilumen multidwell (MLMD); central-lumen multidwell (CLMD); and central-lumen single-dwell (CLSD) loading of the Contura catheter. For this study, a successful treatment plan achieved ideal dosimetric goals and included the following: ≥ 95% of the prescribed dose (PD) covering ≥ 95% of the target volume (TV); maximum skin dose ≤ 125% of the PD; maximum rib dose ≤ 145% of the PD; and V150 ≤50 cc and V200 ≤ 10 cc. Between January 2008 and February 2011, 23 institutions participated. A total of 318 patients were available for dosimetric review. Using the Contura MLB, all dosimetric criteria were met in 78.93% of cases planned with MLMD versus 55.38% with the CLMD versus 37.66% with the CLSD (P ≤.0001). Evaluating all patients with the full range of skin to balloon distance represented, median maximum skin dose was reduced by 12% and median maximum rib dose by 13.9% when using MLMD-based dosimetric plans compared to CLSD. The dosimetric benefit of MLMD was further demonstrated in the subgroup of patients where skin thickness was <5 mm, where MLMD use allowed a 38% reduction in median maximum skin dose over CLSD. For patients with rib distance <5 mm, the median maximum rib dose reduction was 27%. Use of the Contura MLB catheter produced statistically significant improvements in dosimetric capabilities between CLSD and CLMD treatments. This device approach demonstrates the ability not only to overcome the barriers of limited skin thickness and close rib proximity, but to consistently achieve a higher standard of dosimetric planning goals.

Surface Mold Brachytherapy for Mycosis Fungoides of the Foot

The purpose of our innovation was to develop a method of conformal irradiation to the skin of the ankle and foot which, in the past, has proven challenging to treat with external beam radiotherapy. A 51-year-old male with previous history of mycosis fungoides presented with a patch of mycosis fungoides in a previously irradiated region of his left ankle and foot. We elected to treat this lesion with HDR surface mold brachytherapy. On examination, there was an erythematous patch on the left ankle and foot involving the dorsum, lateral aspect, Achilles region and medial malleolar fossa, sparing the sole. The CTV was identified and a thermoplastic mold of the foot was created. 14 flexible brachytherapy catheters were affixed to the mold and a planning CT was performed. The prescription was 2500 cGy in 10 daily fractions to the skin surface. The total skin target volume to be treated was 50.23 cm3. CTV D90 was 97.2% demonstrating excellent target coverage. The plan also displayed good homogeneity, with mean, maximum and minimum skin doses of 102.6%, 115.2% and 93.6% and a heterogeneity index of 0.97. The surface mold performed well during treatments and was sufficiently durable. In this case report, we have applied surface mold brachytherapy to region of the body that in the past has proven challenging to treat with external beam radiotherapy. We have demonstrated that surface mold brachytherapy is a versatile method of radiotherapy that can achieve excellent target coverage and homogeneity while maximizing normal tissue sparing.

Malignant obstructive jaundice – brachytherapy as a tool for palliation

PurposeMalignant obstructive jaundice (MOJ) is relieved by stenting via endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography and biliary drainage (PTCD). Stent occlusion rates of 30-45% have been reported in literature due to tumor ingrowth or overgrowth. We prospectively evaluated the feasibility and the role of intraluminal brachytherapy (ILBT) in preventing stent blockage in patients with MOJ after PTCD and stenting.Material and methodsTwelve patients with MOJ who underwent PTCD followed by self expanding metallic stent (SEMS) placement were prospectively enrolled in this study. Written informed consent was obtained. Intraluminal brachytherapy was done once patient was stable and serum bilirubin was less than 2 mg% or 50% of baseline value. On the day of ILBT, 6 French brachytherapy catheters were placed across malignant stricture under fluoroscopic guidance with placement of the tip 1 cm distal to stricture. A dose of 10 to 14 Gy was delivered at 1 cm from central axis of the source. Suitable patients also received external beam radiotherapy (EBRT) with weekly concurrent chemotherapy.ResultsAll patients tolerated the procedure well with minimal acute and late toxicities. Duodenal ulceration was observed in 1 patient. At a mean follow up of 10.25 months (5-24 months), stents were patent in 10/12 subjects and stent patency duration of 9.8 months (5-22) was reported.ConclusionsIntraluminal brachytherapy post PTCD is feasible and effective in preventing stent occlusion with minimal acute and late toxicities.

Fentanyl Pectin Nasal Citrate (FPNC) to Control Breakthrough Pain (BP) and Improve Dysphagia in Head-and-Neck Cancer Patients Receiving Radiation Therapy (RT)

applicator was constructed by attaching brachytherapy catheters at 1 cm intervals to a 5 mm thick bolus. Two treatment plans were generated for brachytherapy: one for Iridum-192 HDR and the other which assumed treatment with 50 kVp EBT using the same applicator. A third plan was generated for a 2 full arc 6 MV photon VMAT (also with a 5 mm thick bolus). The target and organs at risk (OARs) were contoured on a simulation CT scan. The prescription was 36 Gy in 8 fractions for a 9 cm 12 cm 1 cm target. The plans were optimized to a standard target coverage (V100% > 98%) and to minimize dose to OARs using Nucletron Oncentra MasterPlan (HDR), Varian BrachyVision (EBT) and Eclipse (VMAT). We compared mean target dose, dose heterogeneity, and doses to OARs. Results: The target V100% and D90% were 98% and 104% (HDR), 100% and 119% (EBT), and 98% and 102% (VMAT). The mean (and range from minimum to 1cc maximum) target doses were HDR 119% (86-157%), EBT 164% (86-271%), and VMAT 104% (96-108%). The Table summarizes mean dose to OARs. Conclusions: EBT provided the least dose to closest OAR (brain) due to rapid dose fall-off of low-energy X-rays, but it resulted in higher mean target doses and more heterogeneity than HDR and VMAT. HDR and VMAT provided similar V100% and D90% target doses. As expected, VMAT provided most dose uniformity. All methods resulted in acceptable normal tissue doses, but they were lower for EBT and VMAT than HDR specifically for this lesion located on the top of the skull. Comparative dosimetry facilitates treatment modality selection for extensive superficial lesions with complex surfaces, irregular contours, and close proximity to OARs. Author Disclosure: S. Park: None. M. Kamrava: None. O. Kayode: None. S.P. Lee: None. M.L. Steinberg: None. D.J. Demanes: None.

Feasibility of Accelerated Partial Breast Irradiation in a Large Inner-City Public Hospital

Breast conserving therapy (BCT) that include breast conserving surgery followed by adjuvant radiation therapy has revolutioned medicine by allowing women to avoid mastectomy. Accelerated partial breast irradiation (APBI) has emerged as a valid alternative to whole-breast irradiation that requires a shorter time commitment. We report our novel experience with APBI at a large public hospital that serves low-income and potentially noncompliant patients. A retrospective chart review was conducted of women who underwent BCT for stage 0-IIA breast cancer from August 2007 to August 2010 treated with APBI with a brachytherapy catheter. Twenty-four patients (20 African American) were considered for APBI. Average age was 61 years. Four patients could not undergo APBI for technical reasons and completed whole-breast irradiation over a 5 week period. Median follow-up was 19 months. Nine patients (37.5 %) had ductal carcinoma-in-situ, and 15 patients (62.5 %) had invasive ductal carcinoma with an average tumor size of 1.1 cm. All patients had negative margins of >2 mm. Two patients (8 %) treated with the brachytherapy catheter had in-breast tumor recurrence. Thus, all 24 patients initially identified for APBI successfully completed adjuvant radiotherapy. Patient compliance with postoperative irradiation is key to minimize local recurrence after BCT for breast cancer. This success with a brachytherapy catheter in underserved women in a U.S. public hospital setting indicates that outcomes of compliance and complications are comparable to nationally published results.

SU‐E‐T‐326: Repeated CT‐Scans in Pulsed Doserate Prostate Brachytherapy: Assessment of Deviations from the Treatment Plan

Purpose: Estimation of deviations between planned and delivered dose in Pulsed Doserate (PDR) brachytherapy for prostate cancer. Methods: A boost of 28.8 Gy is given with PDR brachytherapy in addition to 46 Gy delivered with External Beam RT. Brachytherapy is given in 24 pulses of 120 cGy, with an interpulse period time of 2.0 hours, resulting in a treatment time of over 46 hours. For 31 patients, additional CT‐scans were made apart from the Treatment Planning CT, i.e., one at 24 hours after start of PDR treatment and one shortly before finishing PDR treatment. On the second and third CT, the brachytherapy catheters were newly reconstructed and the treating physician delineated the PTV and organs at risk. Dwell positions and dwell times as used for the original Treatment Plan were imported into the newly reconstructed catheters and the dose distribution was recalculated. Plan comparison parameters were prostate V100 and D90 and rectum and bladder D2cc. Results: Averaged over 3 CT scans and all patients, the prostate V100 decreased 1.2% and D90 decreased 2.7%. For rectum, D2cc was within the tolerance dose (96 cGy/pulse) for all patients on the planning CT, but exceeded the tolerance dose on scan #2 in 7/31 patients with maximally 46% and in scan #3 in 5/25 patients with maximally 29%. Also for bladder D2cc was within the tolerance dose (120 cGy/pulse) for all patients on the planning CT. Here, the tolerance dose was exceeded on scan #2 in 2/31 patients with maximally 14% and in scan #3 in 3/25 patients with maximally 28%. Conclusions: In PDR prostate brachytherapy the relatively long treatment time has no clinically relevant deteriorating effect on the dosimetric quality of the treatment. PTV dose hardly deviates from planned dose, while OAR tolerance doses are rarely exceeded and only in small volumes.

1229 ROBOT-ASSISTED LAPAROSCOPIC INTRAOPERATIVE BRACHYTHERAPY: A PORCINE TRIAL

You have accessJournal of UrologyTechnology & Instruments: Robotics - Malignant Disease & Benign Disease I1 Apr 20121229 ROBOT-ASSISTED LAPAROSCOPIC INTRAOPERATIVE BRACHYTHERAPY: A PORCINE TRIAL Jennifer Yates, Dan Smith, Stephen Musialek, Ravi Munver, Ihor Sawczuk, Samay Jain, and Loren Godfrey Jennifer YatesJennifer Yates Hackensack, NJ More articles by this author , Dan SmithDan Smith Teaneck, NJ More articles by this author , Stephen MusialekStephen Musialek Hackensack, NJ More articles by this author , Ravi MunverRavi Munver Hackensack, NJ More articles by this author , Ihor SawczukIhor Sawczuk Hackensack, NJ More articles by this author , Samay JainSamay Jain Hackensack, NJ More articles by this author , and Loren GodfreyLoren Godfrey Hackensack, NJ More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.1519AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Intraoperative brachytherapy using an electronic brachytherapy source is currently utilized for dermatologic and breast malignancies. Patients with advanced urologic disease are often treated with multimodal therapy, including surgical excision and postoperative radiotherapy. Delivery of intraoperative brachytherapy at the time of surgery is limited in part by the radiation source and a means of delivering the brachytherapy in a minimally-invasive fashion. The Xoft electronic brachytherapy device is portable and does not require operative room shielding. A minimally-invasive intraoperative radiotherapy (IORT) technique has been developed which utilizes the robotic platform, the Xoft electronic brachytherapy source, and minimally-invasive applicators. The feasibility of applying this system to a pelvic target in the porcine model was explored. METHODS In-vivo trials were conducted at the David Jurist Research Institute at Hackensack University Medical Center after obtaining IACUC Board approval. A DaVinci standard Robotic Surgical System was used to manipulate minimally-invasive brachytherapy applicators and Axxent electronic brachytherapy catheters (Xoft Inc., Sunnyvale, CA). A porcine pelvic target was identified that served as a surrogate for periprostatic tissue in the human patient. RESULTS Trocars were placed in a fashion similar to a prostatectomy template, with three robotic arms (8 mm trocars) and one 12 mm assistant trocar utilized. Two of the robotic arms were equipped with grasping instruments, and the third robotic arm was equipped with a forceps to manipulate the GafChromic paper. The Axxent electronic brachytherapy applicator was advanced through the 12 mm assistant trocar. While the minimally-invasive applicator was held in position with the robotic instruments, the brachytherapy catheter was used to deliver a prescribed brachytherapy treatment plan to the target. The minimally-invasive applicator could access the targeted site. Optimal stability of the applicator required two robotic arms. On average, five minutes were required to introduce, place, and stabilize the applicator. CONCLUSIONS The minimally invasive IORT system described above can be reproducibly deployed in-vivo. Additional in-vivo studies are needed to further characterize systematic and operator dependent variance and perform quantitative dose analysis. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e497 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jennifer Yates Hackensack, NJ More articles by this author Dan Smith Teaneck, NJ More articles by this author Stephen Musialek Hackensack, NJ More articles by this author Ravi Munver Hackensack, NJ More articles by this author Ihor Sawczuk Hackensack, NJ More articles by this author Samay Jain Hackensack, NJ More articles by this author Loren Godfrey Hackensack, NJ More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Electromagnetic navigation bronchoscopy: A descriptive analysis.

Electromagnetic navigation bronchoscopy (ENB) is an exciting new bronchoscopic technique that promises accurate navigation to peripheral pulmonary target lesions, using technology similar to a car global positioning system (GPS) unit. Potential uses for ENB include biopsy of peripheral lung lesions, pleural dye marking of nodules for surgical wedge resection, placement of fiducial markers for stereotactic radiotherapy, and therapeutic insertion of brachytherapy catheters into malignant tissue. This article will describe the ENB procedure, review the published literature, compare ENB to existing biopsy techniques, and outline the challenges for widespread implementation of this new technology.

Brachytherapy catheter spacing and stabilization technique

Purpose/ObjectivesTo facilitate catheter spacing, implant stability, and patient comfort during multicatheter interstitial brachytherapy. Methods and MaterialsUniform and consistent spacing of multiple interstitial implant catheters can be difficult because individual catheters may become displaced during the course of treatment. The authors have developed a brachytherapy catheter fixation method using Jackson-Pratt (JP) drains that can be used within wounds to maintain catheter spacing or on the skin surface for applicator fixation. JP drains are threaded over the implant needles to space and stabilize the implant geometry. The needles are then replaced with the usual brachytherapy catheters. ResultsSurgically directed (“open”) placement of implant catheters is less prone to displacement when a drain connects and spaces the catheters in the wound. Fixation on the skin surface can also be achieved with the JP drains, which make the friction buttons optional. The soft drain material helps avoid discomfort and pressure injury sometimes associated with hard plastic buttons. Small (10 French) round JP drains are suitable for breast, and head and neck sites and larger 7×10-mm flat JP drains for extremity sarcomas, abdominal, or thoracic tumors. ConclusionsThe complex brachytherapy devices fashioned from widely available surgical drains effectively guide and maintain geometry for multicatheter interstitial implants. Stable implant geometry leads to more reliable implementation of brachytherapy dosimetry. Patient comfort is improved and soft tissue injury from hard-edged buttons is avoided.

Perioperative interstitial CT-based brachytherapy boost in breast cancer patients with breast conservation after neoadjuvant chemotherapy

Intraoperative placement of catheters in the tumor bed during breast-conserving surgery (BCS) enables postponed targeted boost irradiation in high risk breast cancer patients. Twenty-three patients with high risk breast cancer underwent neoadjuvant chemotherapy and multifractionated perioperative brachytherapy as a boost to the tumor bed using three-dimensional (3D) CT-based planning. Plastic catheters for brachytherapy were implanted during surgery and targeted irradiation was delivered in the course of 2-3 weeks. Acute and late toxicities were scored according to the RTOG Common Toxicity Criteria. Cosmetic outcomes were assessed using the Harvard criteria. No major perioperative complications were recorded. Circumscribed wound infection occurred in one patient (4.3%). Only 3 patients (13%) experienced acute skin toxicity Grade 1. We observed no teleangiectasias or pigmentations. The cosmetic outcome at last follow-up visit was rated as excellent/good, in 82.6%, fair, in 13% and poor in 4.4% of patients, respectively. There was no evidence of disease recurrence after median follow-up of 43. 4 months. Systematic integration of the perioperative fractionated 3D CT-based HDR brachytherapy as a boost for patients with breast cancer after BCS is feasible and seems safe. It might be beneficial especially for women with high risk of local recurrence.

Initial clinical experience with multilumen brachytherapy catheters for accelerated partial breast irradiation

PurposeTo review the initial experience of three institutions using multilumen catheters to deliver accelerated partial breast irradiation (APBI) and evaluate dosimetric improvements. Methods and MaterialsPatients were eligible for this analysis if they met criteria for accelerated partial breast irradiation at their respective institution and were not enrolled on the national Phase III trial. Minimum guidelines for treatment planning from the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol were followed. Toxicities were coded using common toxicity criteria version 3.0 criteria. ResultsSixty-two patients were analyzed as part of this study. Median skin spacing was 11mm with a median skin dose of 86.9% (% of prescription dose [PD]). Median rib dose was 76.1% of the PD (range, 4.3–155.7%). The V90, V95, and V100 of the PD for the planning target volume evaluation was 95.4%, 95.2%, and 80.3%, respectively. Seven patients had both skin and rib spacing <7mm, with the median skin dose and rib dose being 113.4% and 130.9% of the PD. For these cases, the median V90, V95, and V100 of the PD was 99.2%, 94.3%, and 81.1%, respectively, whereas the median V150 and V200 were 22.5cc and 7.4cc. Overall, Grade I and II radiation dermatitis were noted in 41.9% and 6.5% of patients. ConclusionThe multilumen device led to improvements in target coverage and normal structure doses compared with traditionally accepted guidelines. Similar toxicities were seen compared with single-lumen devices, even in patients with skin and rib spacing <7mm.

Rebuttal to Dr. Cuttino

What has not been mentioned in the reference to treatment volume with the SAVI, published in the same papers, is that 5% of these patients had skin bridges of <3 mm and 27% <7 mm, and 7% had both chest wall and skin <7 mm. When normal tissues are that close, the PTV is trimmed (per B-39 guidelines, excluding pectoralis/chestwall and 5-mm margin from the skin) leading to smaller targets, or PTV-EVALs ( [1] Yashar C.M. Blair S. Wallace A. et al. Initial clinical experience with the Strut-Adjusted Volume Implant brachytherapy applicator for accelerated partial breast irradiation. Brachytherapy. 2009; 8: 367-372 Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar ). Again, published data demonstrate that based on device size without the need to spare normal tissues, the average-treated PTV-EVAL is equivalent for the 8-1 SAVI, the 10-1 SAVI, and the Contura and MammoSite balloons. Therefore, the argument that the balloon devices treat more tissue is just not based on the published data ( 1 Yashar C.M. Blair S. Wallace A. et al. Initial clinical experience with the Strut-Adjusted Volume Implant brachytherapy applicator for accelerated partial breast irradiation. Brachytherapy. 2009; 8: 367-372 Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar , 2 Dickler A. Kirk M. Choo J. et al. Treatment volume and dose optimization of MammoSite breast brachytherapy applicator. Int J Radiat Oncol Biol Phys. 2004; 59: 469-474 Abstract Full Text Full Text PDF PubMed Scopus (69) Google Scholar , 3 Arthur D.W. Vicini F.A. Todor D.A. et al. Improvements in critical dosimetric endpoints using the Contura multilumen balloon breast brachytherapy catheter to deliver accelerated partial breast irradiation: Preliminary dosimetric findings of a phase IV trial. Int J Radiat Oncol Biol Phys. 2011; 79: 26-33 Abstract Full Text Full Text PDF PubMed Scopus (32) Google Scholar ).

Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

Eliminating Dose To Organs At Risk During Proton Accelerated Partial Breast Irradiation (APBI) Though Temporary, Minimally Invasive Tissue Displacement: Proof Of Principle In Silico

To demonstrate that placement of a breast implant could be used to eliminate dose to normal tissues beyond the breast in proton APBI for deep tumor beds. APBI organ at risk dose is greatly reduced in patients with breast implants due to the extended radiological distance between the tumor bed and the chest wall. An interventional radiology based approach could feasibly be used to expand small, temporary breast implants to extend the radiological distance from the tumor bed to the chest wall, heart, and lung in a minimally invasive procedure that would be comparable to the placement of a brachytherapy catheter.

64 Robot assisted laparascopic brachytherapy catheter implantation in bladder cancer: introduction of a new technique

64 Robot assisted laparascopic brachytherapy catheter implantation in bladder cancer: introduction of a new technique

Multilumen breast brachytherapy in patients with 5 mm or less balloon surface-skin distance using the Contura brachytherapy catheter.

108 Background: To evaluate the toxicity of multilumen breast brachytherapy in patients with 5 mm or less balloon surface-skin distance (BSD) treated with the Contura catheter. Methods: From September 2008 through February 2010 a total of 411 patients with early-stage breast cancer (stages 0, I, IIA) were treated with multilumen HDR brachytherapy for definitive APBI using the Contura brachytherapy catheter. Of those patients 92 had a balloon surface-skin distance (BSD) of 5 mm or less, with 6 months clinical follow-up. All patients received 34 Gy in 10 fractions bid over 5 days. The PTV_EVAL (cc) defined as a 1 cm expansion from the anterior surface of the device; BSD (mm) defined as the distance from the closest point on the balloon to the closet point on the skin surface; maximum skin dose (% and cGy); the volume of breast tissue (cc) receiving 150% and 200% of the prescription dose (V150, V200). Patient toxicity was evaluated at 1 week, 1 month, and 6 months following brachytherapy including; skin reaction (RTOG Acute Radiation Morbidity Scoring Criteria), pigmentation, telangiectasia, pain, fat necrosis, symptomatic seroma. Results: The mean BSD was 3.7 mm, with a range of 1-5 mm. The mean maximum skin dose was 4508 cGy (132.5%). The mean V150 was 21 cc and the V200 was 4.7 cc. The mean PTV_EVAL V90 was 93.7%. 49% of patients had skin reaction, including at 1 week; 47% Grade 1, 0% Grade 2 or 3. At 1 month; 31% Grade 1, 14% Grade 2 and 0% Grade 3. At 6 months; 2% Grade 1, 2% Grade 2 and 0% Grade 3. 6.5 % developed pigmentation changes (hypo or hyper). 5.4% developed telangiectasias, 9.7% reported pain. No patients had fat necrosis, and 15.2 % had a symptomatic seroma. 1 patient had wound dehiscence (maxium skin dose 4195 cGy, 123.4% of prescribed dose). Patients that experienced toxicity had no difference in BSD (3.6 vs 3.9 mm) or in the maximum skin dose (132.6% vs. 132.6%) compared to those that did not experience toxicity. Conclusions: Breast brachytherapy in patients with 5 mm or less BSD has acceptable toxicity with proper planning using the Contura multilumen catheter. Careful attention to maximum skin dose must be used, and we recommend not exceeding 145 % (4,930 cGy) of the prescribed dose.