2
|
Merrell KW, Davis BJ, Goulet CC, Furutani KM, Mynderse LA, Harmsen WS, Wilson TM, McLaren RH, Deufel CL, Birckhead BJ, Funk RK, McMenomy BP, Stish BJ, Choo CR. Reducing seed migration to near zero with stranded-seed implants: Comparison of seed migration rates to the chest in 1000 permanent prostate brachytherapy patients undergoing implants with loose or stranded seeds. Brachytherapy 2019; 18:306-312. [PMID: 30853392 DOI: 10.1016/j.brachy.2019.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 01/10/2019] [Accepted: 01/18/2019] [Indexed: 12/25/2022]
Abstract
PURPOSE Pulmonary seed emboli to the chest may occur after permanent prostate brachytherapy (PPB). The purpose of this study is to analyze factors associated with seed migration to the chest in a large series of PPB patients from a single institution undergoing implant with either loose seeds (LS), mixed loose and stranded seeds (MS), or exclusively stranded seeds in an absorbable vicryl suture (VS). METHODS AND MATERIALS Between May 1998 and July 2015, a total of 1000 consecutive PPB patients with postoperative diagnostic chest x-rays at 4 months after implant were analyzed for seed migration. Patients were grouped based on seed implant technique: LS = 391 (39.1%), MS = 43 (4.3%), or VS = 566 (56.6%). Univariate and multivariate analysis were performed using Cox proportional hazards regression models to determine predictors of seed migration. RESULTS Overall, 18.8% of patients experienced seed migration to the chest. The incidence of seed migration per patient was 45.5%, 11.6%, and 0.9% (p < 0.0001), for patients receiving LS, MS, or VS PPB, respectively. The right and left lower lobes were the most frequent sites of pulmonary seed migration. On multivariable analysis, planimetry volume (p = 0.0002; HR = 0.7 per 10 cc [0.6-0.8]), number of seeds implanted (p < 0.0001, HR = 2.4 per 25 seeds [1.7-3.4]), LS implant (p < 0.0001, HR = 15.9 [5.9-42.1]), and MS implant (p = 0.001, HR = 7.9 [2.3-28.1]) were associated with seed migration to the chest. CONCLUSIONS In this large series, significantly higher rates of seed migration to the chest are observed in implants using any LS with observed hazard ratios of 15.9 and 7.9 for LS and MS respectively, as compared with implants using solely stranded seeds.
Collapse
Affiliation(s)
| | - Brian J Davis
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN.
| | | | | | | | - W Scott Harmsen
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | | | | | | | - Brandon J Birckhead
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI
| | - Ryan K Funk
- Department of Radiation Oncology, Minnesota Oncology, Minneapolis, MN
| | | | - Bradley J Stish
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - C Richard Choo
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| |
Collapse
|
3
|
Hirose K, Sato M, Hatayama Y, Kawaguchi H, Komai F, Sohma M, Obara H, Suzuki M, Tanaka M, Fujioka I, Ichise K, Takai Y, Aoki M. The potential failure risk of the cone-beam computed tomography-based planning target volume margin definition for prostate image-guided radiotherapy based on a prospective single-institutional hybrid analysis. Radiat Oncol 2018; 13:106. [PMID: 29880006 PMCID: PMC5992771 DOI: 10.1186/s13014-018-1043-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/02/2018] [Indexed: 11/10/2022] Open
Abstract
Background The purpose of this study was to evaluate the impact of markerless on-board kilovoltage (kV) cone-beam computed tomography (CBCT)-based positioning uncertainty on determination of the planning target volume (PTV) margin by comparison with kV on-board imaging (OBI) with gold fiducial markers (FMs), and to validate a methodology for the evaluation of PTV margins for markerless kV-CBCT in prostate image-guided radiotherapy (IGRT). Methods A total of 1177 pre- and 1177 post-treatment kV-OBI and 1177 pre- and 206 post-treatment kV-CBCT images were analyzed in 25 patients who received prostate IGRT with daily localization by implanted FMs. Intrafractional motion of the prostate was evaluated between each pre- and post-treatment image with these two different techniques. The differences in prostate deviations and intrafractional motions between matching by FM in kV-OBI (OBI-FM) and matching by soft tissues in kV-CBCT (CBCT-ST) were compared by Bland-Altman limits of agreement. Compensated PTV margins were determined and compensated by references. Results Mean differences between OBI-FM and CBCT-ST in the anterior to posterior (AP), superior to inferior (SI), and left to right (LR) directions were − 0.43 ± 1.45, − 0.09 ± 1.65, and − 0.12 ± 0.80 mm, respectively, with R2 = 0.85, 0.88, and 0.83, respectively. Intrafractional motions obtained from CBCT-ST were 0.00 ± 1.46, 0.02 ± 1.49, and 0.15 ± 0.64 mm, respectively, which were smaller than the results from OBI-FM, with 0.43 ± 1.90, 0.12 ± 1.98, and 0.26 ± 0.80 mm, respectively, with R2 = 0.42, 0.33, and 0.16, respectively. Bland-Altman analysis showed a significant proportional bias. PTV margins of 1.5 mm, 1.4 mm, and 0.9 mm for CBCT-ST were calculated from the values of CBCT-ST, which were also smaller than the values of 3.15 mm, 3.66 mm, and 1.60 mm from OBI-FM. The practical PTV margin for CBCT-ST was compensated with the values from OBI-FM as 4.1 mm, 4.8 mm, and 2.2 mm. Conclusions PTV margins calculated from CBCT-ST might be underestimated compared to the true PTV margins. To determine a reliable CBCT-ST-based PTV margin, at least the systemic error Σ and the random error σ for on-line matching errors need to be investigated by supportive preliminary FM evaluation at least once.
Collapse
Affiliation(s)
- Katsumi Hirose
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan. .,Department of Radiation Oncology, Southern Tohoku BNCT Research Center, 7-10, Yatsuyamada, Koriyama, Fukushima, 963-8052, Japan.
| | - Mariko Sato
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshiomi Hatayama
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Hideo Kawaguchi
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Fumio Komai
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Makoto Sohma
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Hideki Obara
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Masashi Suzuki
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Mitsuki Tanaka
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Ichitaro Fujioka
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Koji Ichise
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshihiro Takai
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.,Department of Radiation Oncology, Southern Tohoku BNCT Research Center, 7-10, Yatsuyamada, Koriyama, Fukushima, 963-8052, Japan
| | - Masahiko Aoki
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| |
Collapse
|
4
|
Analysis of the relationship between prescribed dose and dosimetric advantage of real-time intraoperatively built custom-linked seeds in iodine-125 prostate brachytherapy. Radiat Oncol 2017; 12:192. [PMID: 29191234 PMCID: PMC5710060 DOI: 10.1186/s13014-017-0932-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 11/24/2017] [Indexed: 11/13/2022] Open
Abstract
Background The purpose of this study was to investigate the differences in the dosimetric advantage of using intraoperatively built custom-linked (IBCL) seeds between permanent iodine-125 (I-125) seed implantation (PI) alone and PI followed by external-beam radiation therapy (EBRT) for prostate cancer. Methods We reviewed the records of 62 patients with localized prostate cancer who received transperineal interstitial brachytherapy with I-125 using free seeds or IBCL seeds. Twenty-four low- and intermediate-risk patients underwent PI alone with the prescribed dose of 160 Gy, and 39 high-risk patients underwent PI with 110 Gy, followed by EBRT with 45 Gy (PI + EBRT). Intraoperative and post-implant dosimetric parameters 1 month after implantation were collected and analyzed. Results The numbers of patients implanted with free seeds and IBCL seeds were 14 (58.3%) and 10 (41.7%), respectively, in the PI group and 25 (65.8%) and 13 (34.2%), respectively, in the PI + EBRT group. In the PI group, although there were significant differences in prostate V100 (p = 0.003) and D90 (p = 0.009) and rectum V100 (p = 0.026) on intraoperative dosimetry, these differences were not found on post-implant dosimetry. In the PI + EBRT group, the dosimetric parameters of IBCL seeds, such as prostate V200 (p = 0.013) and V250 (p = 0.010) and urethra D30 (p = 0.038), were better than those of free seeds on intraoperative dosimetry. Furthermore, even on post-implant dosimetry, prostate D90 (p = 0.004), V150 (p = 0.001), and homogeneity index (HI, p = 0.001), as well as V200 (p = 0.001) and V250 (p = 0.020), and urethra D5 (p = 0.008) as well as D30 (p = 0.003) had a better dosimetric quality in IBCL seeds than in free seeds. There was no significant difference in the operation time between free seeds and IBCL seeds in each PI and PI + EBRT group. Conclusions Our results reveal that greater dosimetric benefits could be obtained using IBCL seeds in the case of permanent implantation with a lower prescribed dose, such as PI + EBRT, rather than PI alone.
Collapse
|