Journal of Contemporary Brachytherapy最新文献

{"title":"Volumetric and dosimetric comparison of computed tomography- and trans-abdominal ultrasound-based volumes for image-guided cervix cancer brachytherapy.","authors":"Juan Carlos Pari Salas, Kevin Aguirre Urviola, Paola Cynthia Smith Benavides, Digna Cristina Santos Flores, Albert Bedregal Cruz, Danny Giancarlo Apaza Véliz","doi":"10.5114/jcb.2025.147944","DOIUrl":"10.5114/jcb.2025.147944","url":null,"abstract":"<p><strong>Purpose: </strong>In cervical cancer, brachytherapy is a key component of multi-disciplinary treatment. Wide scale studies, such as EMBRACE, demonstrate benefits of volume-oriented and image-guided brachytherapy. However, MRI and CT are too expensive for health systems with scarce resources. The aim of the study was to assess whether ultrasound- and CT-based volumes of high-risk clinical target volume (HR-CTV) in organs at risk (OARs) as well as dose values in a given plan are comparable.</p><p><strong>Material and methods: </strong>Eighteen applications were evaluated. After CT scans, axial ultrasound images were acquired in 5 mm steps, serving as a secondary set. Post-prescription, HR-CTV, bladder, and rectum were contoured on ultrasound images. Image sets were compared using CT-based volumes as primary reference. Dice coefficient and Jaccard index were calculated. CT-based dosimetric plan was then compared with ultrasound-based volumes to determine D₉₀ HR-CTV, D_2cc bladder, and D_2cc rectum, and these were compared with CT-based values.</p><p><strong>Results: </strong>The mean dose differences between CT and ultrasound volumes for HR-CTV and D_2cc rectum were less than 5%, with the bladder slightly above 5%. Wilcoxon test showed no significant difference between the mean doses for CT and ultrasound. Dice coefficients indicated good to very good correlation for these volumes.</p><p><strong>Conclusions: </strong>Ultrasound-based volume acquisition appears comparable with CT volumetric acquisition in both dosimetric and volumetric terms. Further studies are needed to validate this technique, potentially offering a more affordable and feasible volume-based brachytherapy option for low-income health systems.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"15-21"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966222/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143797001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Auxetic solution for enhanced esophageal brachytherapy applicator.","authors":"Jerome Jean-Joseph, Nikolaus Balagiannis, Markus W Scheppach, Selin Temizel, Alanna Ebigbo, Helmut Messmann, Tilman Janzen, Georg Stüben","doi":"10.5114/jcb.2025.147780","DOIUrl":"10.5114/jcb.2025.147780","url":null,"abstract":"<p><strong>Purpose: </strong>In this study, a novel auxetic applicator equipped with four-channel catheters for esophageal brachytherapy was presented.</p><p><strong>Material and methods: </strong>The applicator, made of a new biocompatible material, has an auxetic helical structure with four channels. Details of applicator modeling, construction, commissioning, and insertion were provided. Initial <i>ex vivo</i> trial conducted on a porcine model was outlined.</p><p><strong>Results: </strong>Simulations and dose calculations closely matched experimental measurements, validating the modeling approach. This applicator achieved highly asymmetric dose distributions. Its unique auxetic helical design allowed smooth insertion, while mitigating sequential inter-fraction hot spot formation.</p><p><strong>Conclusions: </strong><i>Ex vivo</i> implementation of the applicator demonstrated feasibility, resulting in consistent and reproducible dose distributions. Initial outcomes showed promise for the applicator's efficacy and versatility in intra-luminal or intra-cavitary applications.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"33-42"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966220/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diaphragm and lung dose in liver high-dose-rate interstitial brachytherapy: A dosimetry and toxicity report.","authors":"Keerthaanaa Yogabalan, Gokula Kumar Appalanaido, Ch'ng Ewe Seng, Jasmin Bin Jalil, Jayapramila Jayamani, Nor Hafizah Ishak, Nursyatina Abdul Raof, Reduan Bin Abdullah, Ahamed Badusha Mohamed Yoosuf, Muhamad Zabidi Ahmad, Bazli Md Yusoff, Mohd Zahri Abdul Aziz","doi":"10.5114/jcb.2025.148297","DOIUrl":"10.5114/jcb.2025.148297","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study was to retrospectively analyze and report on dose-volume and clinical toxicity of liver high-dose-rate interstitial brachytherapy (HDR-IBT) used in diaphragm and lung tissue.</p><p><strong>Material and methods: </strong>Computed tomography (CT)-based liver HDR-IBT using Oncentra Brachy treatment planning system (TPS) plans of patients with malignant liver tumor (MLT) from September 2018 to June 2023 were reviewed to identify patients, whose diaphragm and lung tissue were within 100% prescription isodose. These organs at risk (OARs) were contoured in axial CT slices. Maximum point dose (D_max), dose to 0.2 cc, 0.5 cc, 1 cc (D_0.2cc, D_0.5cc, D_1cc), and volume receiving 30 Gy and 50 Gy (V_30Gy and V_50Gy) were analyzed. Toxicity data of these patients were retrieved from hospital electronic records.</p><p><strong>Results: </strong>The analysis included 27 patients with 43 and 36 MLTs, whose 100% prescription isodose of liver HDR-IBT plan was within diaphragm and lung tissue. Median prescription dose was 25 Gy (range, 15-25 Gy) in single-fraction. Median D_max, D_0.2cc, D_0.5cc, and D_1cc of the diaphragm were 302 Gy (range, 54-396 Gy), 68 Gy (range, 38-234 Gy), 48 Gy (range, 32-128 Gy), and 35 Gy (range, 27-88 Gy), while for the lung, 90 Gy (range, 39-295 Gy), 55 Gy (range, 32-207 Gy), 44 Gy (range, 29-117 Gy), and 34 Gy (range, 25-79 Gy), respectively. Median V_30Gy and V_50Gy for the diaphragm were 1.1 cc (range, 0-5.8 cc) and 0.2 cc (range, 0-2.5 cc), while for the lung, 0.8 cc (range, 0-10.1 cc) and 0.1 cc (range, 0-2.3 cc), receptively. Two patients with repeated HDR-IBT sessions received cumulative D_max diaphragm of 698 Gy and 792 Gy. At median follow-up of 23 months, no patient reported any suspicious symptom of radiation-induced diaphragm or lung injury.</p><p><strong>Conclusions: </strong>This is the first publication reporting diaphragm and lung tissue dose-volume and clinical toxicity in liver HDR-IBT. Small volume of diaphragm and lung tissue tolerated extreme high radiation doses [5 times of stereotactic body radiotherapy (SBRT) range in single fraction] without clinically significant toxicity. A standardized reporting for diaphragm and lung dose volume is needed for future liver HDR-IBT studies. The results of the current study can be employed in future for expanded indication of brachytherapy, such as CT-guided trans-thoracic lung brachytherapy.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"28-32"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966225/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical implementation of interstitial brachytherapy in early-stage oral cancer in a newly commissioned tertiary cancer center: Challenges and initial experience.","authors":"Rohit Avinash Vadgaonkar, Raghavendra Hajare, Sreelakshmi Kk, Ankita Mehta, Kiriti Chiriki, Pankaj Chauhan, Taushiful Hoque, Chandrasekhar Dravid, Sasi Krishna Kavutarapu, Nageswara Rao Noothanapati, Sneha Nachu, Raviteja Miriyala, Umesh Mahantshetty","doi":"10.5114/jcb.2025.148374","DOIUrl":"10.5114/jcb.2025.148374","url":null,"abstract":"<p><strong>Purpose: </strong>High-dose-rate (HDR) interstitial brachytherapy (ISBT) is a curative treatment option for head and neck cancer patients. However, its overall utilization has been declining, particularly in newer cancer setups. This study investigated challenges in ISBT implementation, and reported initial outcomes of early-stage oral cancer patients in a newly established tertiary cancer center.</p><p><strong>Material and methods: </strong>After reviewing guidelines and addressing administrative requirements, ISBT program was launched. Key steps in the process included establishing brachytherapy suite, staff training, and optimizing workflows. Alongside standard protocols, additional procedures, such as clinical drawing templates, intra-oral ultrasound, and intra-oral spacers were implemented. From August 2020 to July 2022, 18 patients with early-stage (cT1-2N0M0) oral cancer (tongue = 13, lip = 3, buccal mucosa = 2) received treatment with either ISBT alone (<i>n</i> = 3) or external beam radiotherapy (EBRT), followed by ISBT with HDR cobalt-60 source (<i>n</i> = 15). Treatment characteristics, oncological outcomes, and morbidity profiles were analyzed.</p><p><strong>Results: </strong>The median age of the cohort was 55 years (range, 29-75 years), with two-thirds of males. The majority had T1 stage (72.2%), with infiltrative growth pattern (72.2%). All patients with oral tongue cancer, 1 lip and 1 buccal mucosa cancer, received elective nodal irradiation with EBRT, followed by ISBT, achieving a total median EQD₂ of 74 Gy. The remaining 3 patients (2 with lip and 1 with buccal mucosa primary) received ISBT alone. Post-treatment complete response was observed in 17 patients (94.4%), with no cases of acute toxicity > grade 2. At a median follow-up of 32 months, an overall 3-year local-regional control and overall survival rates were 67.9% and 72.7%, respectively. One patient developed grade 3 myelopathy, and one grade 3 osteoradionecrosis.</p><p><strong>Conclusions: </strong>Implementing ISBT in a newly established cancer center is feasible and effective for early-stage oral cancer, providing moderate oncological outcomes with manageable toxicity profile.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"1-14"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966224/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Image-guided high-dose-rate interstitial brachytherapy with custom-made surface applicators for lower lip cancer as monotherapy. Technique, long-term clinical results, and quantitative dose-volume evaluation: A case series.","authors":"Hironori Akiyama, Ken Yoshida, Tadayuki Kotsuma, Tadashi Takenaka, Yuji Takaoka, Masataka Nakai, Manabu Kano, Hitoshi Yoshimoto, Kentaro Ozawa, Zoltán Takácsi-Nagy, Koji Masui, Hideya Yamazaki, Yoshiko Ariji, Eiichi Tanaka","doi":"10.5114/jcb.2025.147943","DOIUrl":"10.5114/jcb.2025.147943","url":null,"abstract":"<p><strong>Purpose: </strong>This study showed long-term clinical results and quantitative dose-volume evaluation of image-guided high-dose-rate interstitial brachytherapy (IG HDR-BT) with custom-made surface applicators for lower lip cancer as monotherapy.</p><p><strong>Material and methods: </strong>Patients with localized lower lip cancer, who received IG HDR-BT with custom-made surface applicators as monotherapy at the NHO Osaka National Hospital between February 2012 and January 2015 were enrolled in this study. One to three applicators were implanted interstitially, and two to six were placed on tumor surface. Planning-aimed dose (PAD) was 54 Gy, 48 Gy for a recurrent case, and irradiation was delivered at 6 Gy/fraction, twice a day. Dosimetric goal was to achieve D₉₀: clinical target volume (CTV) > PAD without excessive dose to the mandible. A lead shield was placed between the gingiva and lower lip during irradiation to reduce the dose to the mandible in all but one edentulous patient. A gauze with 2% lidocaine was inserted intra-orally to reduce the dose to the upper lip and maxilla.</p><p><strong>Results: </strong>Six patients (T1 : T2 : T3 = 3 : 2 : 1), including one recurrent case, were enrolled in this study. The CTV was contoured on computed tomography and in two cases, magnetic resonance imaging was used as a reference for contouring. The median follow-up was 69.5 months. The primary tumor was controlled in all cases. No serious late adverse reactions were observed. The median D₉₀ (CTV) and V₁₀₀ (PAD) were 108.9% PAD and 99.3% CTV, respectively. The median D_0.1cm3 (mandible) was 3.2 Gy per fraction.</p><p><strong>Conclusions: </strong>IG HDR-BT with custom-made surface applicators for lower lip cancer as monotherapy showed an excellent CTV dose and acceptable doses to the mandible, with good long-term clinical results.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"62-69"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966219/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Skin marker for MR-only surface high-dose-rate brachytherapy.","authors":"Evangelia Kaza, Phillip M Devlin, Desmond O'Farrell, Ivan Buzurovic","doi":"10.5114/jcb.2025.148107","DOIUrl":"10.5114/jcb.2025.148107","url":null,"abstract":"<p><strong>Purpose: </strong>Recent advances in surface high-dose-rate (HDR) brachytherapy imaging indicate that flap applicators, human skin, and fibromatosis can be visualized using MRI. Complete MR-only surface brachytherapy workflows would require skin marker identification to define clinical target edges. However, CT markers are not detected on MR images, and common MR markers are unsuitable for continuous surface target tracing. In this paper, we proposed an alternative skin marker that was evaluated for MRI and CT detectability and contourability using a brachytherapy treatment planning system (TPS).</p><p><strong>Material and methods: </strong>Commercially obtained silicone rubber tubes of 2 or 3 mm diameter were taped on the hand of an anthropomorphic phantom, a healthy volunteer, and three palmar fascial fibromatosis patients. Subjects were imaged with an optimized 3D pointwise encoding time reduction with radial acquisition (PETRA) sequence, and a volumetric interpolated breath-hold examination (VIBE) sequence with Dixon reconstruction. Additionally, patients underwent standard CT imaging. Obtained images were reviewed for tube conspicuity, and tubes were tracked on axial views using Oncentra Brachy TPS. Independent tube and muscle reference contours were drawn in MIM for quantitative analysis, considering the three orthogonal imaging planes.</p><p><strong>Results and conclusions: </strong>Silicone rubber tubes were detected with positive signal on PETRA, VIBE, and CT images. Among the MR series, Dixon VIBE fat-only showed the highest contrast against muscle tissue and the best separation from human skin, followed by DIXON opposed-phase. 3 mm diameter tubes were tracked better by TPS than 2 mm diameter ones. Considering MR images in the three orthogonal planes in MIM was more helpful for localizing the entire tube than using axial images only in TPS. All obtained contour shapes generally agreed with the known tube positions. Overall, solid silicone rubber tubes of 3 mm diameter represent a suitable skin marker alternative to CT markers for MR-only surface HDR brachytherapy.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"43-53"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966218/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143797000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Active ultrasound tracking method for prostate brachytherapy using acoustic needle prototype and sonomicrometry.","authors":"Marek Belohlavek, Minako Katayama, Christopher L Deufel","doi":"10.5114/jcb.2025.148031","DOIUrl":"10.5114/jcb.2025.148031","url":null,"abstract":"<p><strong>Purpose: </strong>This study examined whether sonomicrometry can measure displacements of active ultrasound-tracked needle prototype for prostate brachytherapy application with high linearity, accuracy, and precision as well as triangulate the needle's motion relative to intra-rectal ultrasound probe.</p><p><strong>Material and methods: </strong>Sonomicrometry detects time-of-flight (ToF) of ultrasound signal transmitted from an active ultrasound-tracked needle (customized with a piezo-electric tracking sensor) to independent sensor. The transmission was tested in water for displacements parallel and perpendicular to the needle axis using distances of up to 35 mm. Three-dimensional (3D) tracking of the active ultrasound-tracked needle utilized a simulated intra-rectal ultrasound probe fitted with 5 piezo-electric sensors, and a sonomicrometry triangulation algorithm was used to measure the distances of the needle from the probe.</p><p><strong>Results: </strong>Incremental displacements of the active ultrasound-tracked needle were measured by sonomicrometry with strong linearity (R ≥ 0.999), high accuracy (mean difference ≤ 0.55 mm), and precision (1.96 × standard deviation of the mean difference ≤ 0.22 mm) compared with a reference. Sporadic false triggering of ToF detection was eliminated by signal inversion. Acoustic spatial tracking by the off-line triangulation algorithm produced virtual 3D wire meshes, which closely spatially overlapped with the corresponding (ground-truth) video clips of active ultrasound-tracked needle movement at several testing time points.</p><p><strong>Conclusions: </strong>We introduced an experimental active ultrasound-tracked needle and employed sonomicrometry to measure the needle's displacements and triangulate its spatial position. The measurements and 3D spatial tracking yielded promising results for potential prostate brachytherapy applications. Clinical implementation will necessitate developments of automated triggering, real-time tracking, and a commercially viable acoustic needle design.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"54-61"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966223/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of medial needles in mitigating dose deficits from sub-optimally inserted tandems in cervical interstitial brachytherapy.","authors":"Maryam Ejaz, Sameed Hussain, Abdus Samad Syed, Muhammad Sohaib Nadeem, Muhammad Shehwar Khan","doi":"10.5114/jcb.2025.148375","DOIUrl":"10.5114/jcb.2025.148375","url":null,"abstract":"<p><strong>Purpose: </strong>In cervical interstitial brachytherapy, sub-optimal tandem insertion can lead to inadequate dose coverage of clinical target volume (CTV). This study aimed to evaluate the effectiveness of medial interstitial needles in optimizing dose to CTV, while minimizing toxicity to organs at risk (OARs), such as bladder, rectum, and sigmoid colon.</p><p><strong>Material and methods: </strong>The study included 25 brachytherapy plans in seven subjects with locally advanced cervical cancer, who had sub-optimal tandem insertions during cervical interstitial brachytherapy, for which 1 or more medial needle was inserted <i>via</i> Utrecht applicator. For each plan, a test plan was created after inactivating medial needles. Doses to 90% of high-risk (HR) CTV (D₉₀) and OARs (D_2cc bladder, rectum, and sigmoid) were evaluated and compared using Wilcoxon signed rank test in SPSS v. 21.0.</p><p><strong>Results: </strong>Compared with plans without medial needles (x̄ = 5.22 ±1.60 Gy, median = 5.68 Gy), the plans with medial needles activated (x̄ = 6.59 ±1.55 Gy, median = 7.08 Gy) achieved 26.2% and 24.6% improvement (<i>p</i> = 0.001) in CTV D₉₀ mean and median, respectively. The mean total dose per patient in the medial needle activated group (x̄ = 82.84 ±6.32 Gy) was significantly greater (<i>p</i> = 0.018), with a mean difference of 8.48 Gy from the medial needle inactivated group. No significant dose difference was observed across OARs. Fifty-two needles were inserted in total, out of which, 39 had more than 2 cm depth. Complete response was seen in all subjects.</p><p><strong>Conclusions: </strong>In patients with sub-optimal tandem insertion, the placement of medial needles can compensate dose deficit, while keeping OARs doses within acceptable constraints. Further studies among larger cohorts are warranted to optimize treatment protocol.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"17 1","pages":"22-27"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966221/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new approach to assess transit dose impact in gynecological and prostate brachytherapy with effective transit time.","authors":"Masato Nishitani, Hiroyuki Okamoto, Satoshi Nakamura, Kotaro Iijima, Takahito Chiba, Hiroki Nakayama, Tetsu Nakaichi, Mihiro Takemori, Yuka Urago, Weishan Chang, Hiroshi Igaki","doi":"10.5114/jcb.2024.146826","DOIUrl":"10.5114/jcb.2024.146826","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study was to evaluate the dosimetric impacts of transit doses in various brachytherapy techniques, e.g., intra-cavitary, interstitial, and hybrid brachytherapy, on prostate and gynecological cancers using commercially available treatment planning system (TPS).</p><p><strong>Material and methods: </strong>For the evaluation, 36 gynecological cancer and 12 prostate cancer treatment plans were investigated, and transit doses were calculated using effective transit time to the middle of dwell positions in TPS. Effective transit times varied with step size, and movements were determined with a high-speed camera. The increment of Δ in dose-volume histogram parameters for clinical target volume (CTV) V_100% and CTV D_90%, rectum D_2cc and D_1cc, and bladder D_2cc and D_1cc were evaluated, after which dwell time distribution for each technique was analyzed to examine relationships between dosimetric change in CTV D_90% and dwell time.</p><p><strong>Results: </strong>The median Δ for interstitial technique in prostate cancer was larger than those in other techniques: that of CTV V_100% was 0.7%, and those of bladder and rectum D_2cc and D_1cc were over 1.0%. In CTV D_90%, the median Δ values for interstitial technique in gynecological and prostate cancers were 1.0% and 1.6%, respectively. The interstitial techniques displayed a positive correlation between Δ of CTV D_90% and the percentage of dwell times of < 2 s of the total dwell times.</p><p><strong>Conclusions: </strong>In this study, the dosimetric impacts of transit doses in various brachytherapy techniques were comprehensively clarified. A relatively large impact was observed in interstitial techniques, and the percentage of dwell times of less than 2 s could be a rough indicator of the necessity of considering the transit dose.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"16 6","pages":"449-456"},"PeriodicalIF":1.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11812138/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143411561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The significance of free-hand needles in cervical cancer brachytherapy.","authors":"Jan-Erik Palmgren, Jan Seppälä, Ester Jääskeläinen, Maarit Anttila","doi":"10.5114/jcb.2024.146672","DOIUrl":"10.5114/jcb.2024.146672","url":null,"abstract":"<p><strong>Purpose: </strong>Modern applicators in cervical cancer brachytherapy (BT) have an integrated option for using interstitial needles. Even though this allows improved dose coverage in large tumors, there are cases where pre-positioned needle arrangements within applicator are not optimal. In such cases, free-hand needles (FHNs) can be inserted into tumor without using applicator's positions. However, this requires a skilled professional, because the depth of tissue must be estimated without any help of needle insertion tools, and the angle of needle is critical. Improved dose coverage of the tumor and the effect on critical organ doses are yet to be estimated, if they constitute the time used and possible additional complication risk using FHNs.</p><p><strong>Material and methods: </strong>In this work, clinical brachytherapy treatment plans using FHNs were compared with hypothetical plans, in which the best possible effort was applied to produce acceptable treatment plans without FHNs. Twenty-four cervix cancer patients with FHNs were re-planned without FHNs. Biological total doses were calculated for target volumes (high-risk clinical target volume [HR-CTV], gross tumor volume [GTV], and intermediate-risk clinical target volume [IR-CTV]) and organs at risk. External beam radiation therapy (EBRT) dose distributions were summed to brachytherapy plans, and total doses were compared.</p><p><strong>Results: </strong>The statistically significant differences favoring FHNs usage were observed, with HR-CTV D₉₀ (<i>p</i> = 0.043), bladder (D_2cc) (<i>p</i> = 0.017), rectum (D_2cc) (<i>p</i> = 0.022), and sigmoid (D_2cc) (<i>p</i> = 0.065). The average 2 Gy equivalent total doses and <i>p</i>-values, without/with FHNs were respectively: HR-CTV D₉₀ = 88.8/91.5 (<i>p</i> = 0.043); bladder (D_2cc) = 87.5/86.2 (<i>p</i> = 0.017); rectum (D_2cc) = 70.2/69.2 (<i>p</i> = 0.022); sigmoid (D_2cc) = 70.1/69.3 (<i>p</i> = 0.065) (α/β = 10 Gy for targets and α/β = 3 Gy for OARs, respectively).</p><p><strong>Conclusions: </strong>The utilization of FHNs resulted in higher dose coverage to HR-CTV, and lower doses to bladder and rectum. There was no difference in GTV, bowel, or vaginal point doses.</p>","PeriodicalId":51305,"journal":{"name":"Journal of Contemporary Brachytherapy","volume":"16 6","pages":"443-448"},"PeriodicalIF":1.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11812140/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143411571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}