Journal of Contemporary Brachytherapy最新文献

Eyelid carcinoma is a tumor often detected at an early stage, which can be managed surgically. In non-surgical cases, brachytherapy is a valid alternative or as adjuvant therapy when risk factors exist. Basal cell carcinoma is the most common type of eyelid cancer, usually occurring in the lower eyelid. Interstitial technique with plastic tubes is a simple procedure in this location. High-dose rate (HDR) brachytherapy offers local control rates greater than 94%, with few side effects and good function preservation. This article provided practical description of the technique and review of literature. Collaboration between ophthalmology, dermatology, and brachytherapy specialists is essential to achieve the best patient outcomes.

Purpose: Salvage external beam radiation therapy (EBRT) followed by vaginal brachytherapy is commonly used to treat patients with vaginal recurrence of endometrial cancer, but limited data are available in the era of modern radiotherapy with intensity-modulated radiotherapy (IMRT) and high-dose-rate brachytherapy (HDR-BT). Our study aimed to assess survival outcomes and late toxicities associated with the combined treatment modality.

Material and methods: A retrospective review of 26 patients with biopsy-proven vaginal recurrence after surgically treated endometrial cancer, for whom salvage EBRT followed by HDR-BT were performed between February 2013 and September 2022. Median EBRT dose was 50 Gy (range, 45-59.4 Gy), and median HDR-BT was 16 Gy (range, 12-24 Gy). Recurrence-free intervals and overall survival (OS) rates were evaluated. Complications were assessed in terms of late RTOG toxicity (grade 3 or higher) of gastrointestinal tract, genitourinary tract, and vagina. Kaplan-Meier and Cox proportional hazards modeling were used to estimate survival. Severe (grade 3 or higher) radiation-related toxicities defined according to RTOG were recorded. Endpoints were measured from the date of diagnosis of vaginal recurrence.

Results: The median follow-up was 36.8 months (range, 4.2-97.8 months). The median age at recurrence was 65.5 years (range, 41-91 years), and the median time to recurrence from primary diagnosis was 20.6 months (range, 2.8-148.1 months). The most common symptom was per vaginal bleeding (30.8%) and vaginal spotting (23.1%). Twenty-four patients (92.3%) had central recurrence (18 vaginal apex, six distal vagina), and two patients (7.7%) had pelvic nodal recurrence with central recurrence. The median tumor size at recurrence was 1.5 cm (range, 0.4-5.0 cm). Eight patients developed a distant recurrence and five of them died due to the disease, with 5-year local control, disease-specific survival, and distant metastatic-free survival rates of 100%, 80.8%, and 69.2%, respectively. The median OS was 91.1 months (range, 15.7-1,503.6 months), and the median distant recurrence-free survival was 46.1 months (range, 7.7-133.8 months). Primary tumor high-grade and stage III were prognostics for poor OS (7.7% and 0%) and distant metastases-free survival (11.5% and 3.8%), respectively. No severe grade 3 or higher late toxicities were observed.

Conclusions: Recurrent vaginal endometrial cancer is amenable to salvage therapy using HDR-BT and EBRT. This combined treatment modality demonstrates excellent loco-regional control and minimal morbidity for vaginal recurrence of endometrial cancer. Early radiotherapy, including brachytherapy, should be considered for women with vaginal recurrence of endometrial cancer.

Image-based adaptive brachytherapy (IGABT) is now the standard of care for patients with locally advanced cervical cancer. EMBRACE-2 MRI-based brachytherapy study demonstrated improved local control rates and reduced morbidity using hybrid applicators. Utilization of these hybrid applicators in gynecological brachytherapy offers advantages over conventional interstitial techniques; however, practical guidance for applicator selection based on disease extent and image findings remains limited. This manuscript aimed to provide a practical framework for applicator selection based on five case scenarios to demonstrate optimal applicator selection tailored to disease extent and anatomical considerations.

Purpose: Coronary artery disease is the leading cause of death for both men and women in the United States. Percutaneous coronary intervention with drug-eluting stents (DES) has been a major advance in treatment. In-stent restenosis (ISR) occurs in up to 10% of patients, and is often managed with repeat DES placement. However, when DES-ISR occurs, treatment options remain limited. Angioplasty followed by intravascular brachytherapy (IVBT) is one option for such patients.

Material and methods: Outcomes of 78 patients (91 vessels) treated with angioplasty followed by strontium-90 IVBT from 2016-2024 were reviewed. Following vessel preparation with angioplasty, an intravascular catheter was introduced into the index lesion. Radiation was prescribed to an area encompassing the angioplasty injury length with a minimum 10 mm margin. Radiation dose delivered was 23 Gy or 18.4 Gy according to protocol standard. Major adverse cardiac events (MACE), including myocardial infarction and stroke as well as all causes of death were analyzed, as was the need for repeat angioplasty or intervention.

Results: All patients had at least 2 drug-eluting stents previously deployed in the affected vessel, and were not technically suitable for additional stenting. One patient expired while receiving intervention due to cardiac arrest, with no other intraprocedural toxicities reported. Median follow-up was 22.8 months (range, 0.9-60.6 months), and forty-four percent of patients experienced symptomatic relief. Major cardiac adverse events rates at interval follow-up of IVBT included myocardial infarction (18%) and stroke (5%). Death from any cause occurred in 16% of patients at a median time of 9.3 months post-treatment (range, 0.5-29.5 months).

Conclusions: Angioplasty followed by intravascular brachytherapy is a safe and effective therapy for patients with complex coronary artery lesions experiencing stent-in-stent restenosis, who have few other treatment options.

Purpose: To design and fabricate a cylindrical silicone applicator for high-dose-rate (HDR) superficial brachytherapy of the fingers, aiming at improving dose coverage, anatomical conformity, and inter-session reproducibility. This device was intended to offer a practical alternative to the limitations of existing commercial applicators.

Material and methods: A solid, assemblable negative mold was designed using 3D printing technology. This mold enabled shaping of the final applicator by casting of pre-mixed and degassed room temperature vulcanized (RTV) silicone. Design featured a central cavity, a 93.5° open segment to facilitate anatomical adaptation, and nine equidistant holes for catheter insertions. Applicator's performance was evaluated on hand phantom, considering efficacy, flexibility, and mechanical stability. Dosimetric planning was based on CT investigations, in which a subcutaneous treatment volume was simulated. Each catheter included eight dwell positions, and dwell times were modulated to optimize dose distribution and spatial conformity.

Results: The applicator exhibited good flexibility, structural integrity, and appropriate adaptation to different finger morphologies. Catheters remained securely positioned during testing, with no displacements observed. The 100% iso-dose line fully encompassed the target volume, and the maximum surface dose reached 129% of the prescribed dose. Most of 120% isodose was confined within the applicator material, indicating an adequate bolus effect. Dwell time modulation contributed to a uniform dose distribution, especially in peripheral and distal regions of the target volume.

Conclusions: The developed applicator represents an effective, accessible, and reproducible solution for the delivery of HDR brachytherapy in superficial finger lesions, supporting its implementation in clinical settings with limited resources.

Purpose: Locally advanced cervical cancer (LACC) in bulky tumors and parametrial invasion poses substantial challenges for effective brachytherapy, often resulting in sub-optimal target coverage and increased risk for adjacent organs. This study evaluated the clinical feasibility, dosimetric performance, and early outcomes of a novel high-dose-rate brachytherapy strategy using patient-specific 3D-printed templates and curved flexible needles in LACC.

Material and methods: We retrospectively analyzed 20 patients with stage IIIB-IVB cervical cancer treated between July 2023 and August 2024. All patients received pelvic intensity-modulated radiotherapy and concurrent cisplatin-based chemotherapy, followed by brachytherapy via a dual-needle technique. Personalized 3D-printed templates were designed on the basis of pre-treatment magnetic resonance imaging to optimize needle trajectories and accommodate anatomical variations. Dosimetric parameters, target coverage, organ at risk doses, and clinical outcomes were assessed.

Results: The mean high-risk clinical target volume (HR-CTV) was V₁₀₀ value of 86.5% (standard deviation of 7.6%), with a mean D₉₀ equivalent dose in 2 Gy fractions (EQD₂) of 89.1 Gy for combined external beam and brachytherapy treatment. The doses to organs at risk remained below the recommended thresholds, with a mean bladder and rectum D_2cc EQD₂ of 79.4 Gy and 72.7 Gy, respectively. At a median follow-up of 12.8 months, the one-year overall survival and progression-free survival rates were 85% and 75%, respectively. No grade 3 or higher acute toxicities were observed.

Conclusions: The integration of 3D-printed templates and curved flexible needles enables precise and individualized brachytherapy for bulky and parametrial invasive cervical cancer, achieving high target conformity and effective organ sparing. This approach demonstrates promising early efficacy and safety, supporting its potent advanced solution for complex LACC cases.

[This corrects the article DOI: 10.5114/jcb.2024.141458.].

Purpose: The optimal anaesthetic choice for gynaecological brachytherapy remains uncertain. While sevoflurane offers rapid recovery due to favourable pharmacokinetics, its higher cost limits affordability in resource-constrained settings. Isoflurane, a less expensive volatile agent, may be a cost-effective alternative if recovery profiles are comparable.

Material and methods: We conducted a prospective, randomised, non-inferiority trial including 100 women with American Society of Anesthesiologists (ASA) physical status I-III undergoing ambulatory intracavitary brachytherapy. Participants were randomly allocated to maintenance anaesthesia with either isoflurane (n = 50) or sevoflurane (n = 50), with anaesthetic depth titrated to maintain a bi-spectral index (BIS) between 40 and 60. The primary outcome was emergence time, defined as the interval from discontinuation of anaesthesia to eye opening after verbal command. Secondary outcomes included time to supraglottic airway removal, haemodynamic stability, postoperative cognitive function, post-anaesthesia care unit (PACU) stay, adverse events, and anaesthetic agent cost. Non-inferiority was prespecified with a margin of 3.2 minutes.

Results: Emergence times were similar between isoflurane and sevoflurane groups (7.13 ±1.60 min vs. 7.24 ±1.70 min; mean difference 0.12 min; 97.5% CI: 0.86 to -0.63), confirming non-inferiority of isoflurane. Secondary outcomes, including airway removal time, haemodynamics, cognitive scores, PACU stay and adverse events, showed no significant differences. Isoflurane administration cost was 61.6% lower compared to sevoflurane (22.2 ±2.77 INR vs. 57.8 ±9.35 INR; p = 0.001).

Conclusions: Isoflurane is non-inferior to sevoflurane for emergence time in short-duration gynaecological brachytherapy, with comparable recovery profiles. Its substantial cost advantage supports its use as an economical anaesthetic option in high-volume, resource-limited oncology settings.

Purpose: To compare manual treatment planning with two inverse planning methods from two different treatment planning systems for high-dose-rate cervical cancer brachytherapy.

Material and methods: Thirty-one consecutive patients were included. Three treatment plans were created: manual, hybrid inverse treatment planning (HIPO), and RayStation Brachy (RSB), using Oncentra TPS for manual and HIPO, and RayStation TPS for RSB. Dose volume parameters, dwell time in intrauterine tandem, ovoids, and interstitial needles as well as Paddick, COIN, and dwell time inhomogeneity index, were evaluated.

Results: Compared with manual planning, HIPO plans resulted in a higher dose to targets while reducing the dose to organs at risk. It reduced the total treatment time and increased the loading in interstitial needles. RSB plans resulted in a similar dose to targets and organs at risk and a similar total treatment time, but a better homogeneity of dose distribution. All dosimetric indices were increased with inverse optimization.

Conclusions: Both inverse planning methods are able to produce dosimetrically acceptable plans, with an increase of target coverage and better homogeneity. RSB provides higher doses and better homogeneity than HIPO.

Purpose: To investigate a semi-automatic hybrid inverse treatment planning optimization (HIPO) approach for gynecological brachytherapy that preserves the pear-shaped dose distribution without relying on dummy structures.

Material and methods: We retrospectively analyzed 29 patients with gynecological cancers, who underwent combined intracavitary and interstitial (IC/IS) brachytherapy. HIPO enables optimization of dwell times for specific applicators, while other applicators are fixed in Oncentra^® Brachy. Clinical treatment plans (CPs) were compared based on manual adjustments using four HIPO methods: H_ovoid, H_free, H_MS, and H_MS*. H_ovoid optimized tandem and IS needles with ovoid dwell time fixed; H_free optimized all applicators with no fixation; H_MS optimized IS needles with fixation using modified Manchester system, with safe organs at risks (OARs) doses generated in advance by graphical optimization. In H_MS* plan, optimization parameters were adjusted to improve high-risk clinical target volume (HR-CTV) dose coverages based on comparisons between CPs and H_MS.

Results: H_ovoid, H_free, H_MS, and H_MS* achieved clinically acceptable DVH parameters in terms of HR-CTV dose coverage and OARs sparing. However, considerable deviations from the conventional pear-shaped dose distributions were observed, particularly with H_free, which exhibited zero dose contribution from ovoid applicators. Among all HIPO plans, H_MS* with adjusted optimization parameters demonstrated the closest HR-CTV D_90% to that of the CP, while maintaining a conventional pear-shaped dose distribution.

Conclusions: We recommend applying the modified Manchester system with safe OARs doses as the object of fixation, given its consistency with the conventional pear-shaped dose distribution. The proposed method demonstrated clinically acceptable dose distribution and DVH parameters.