Selective internal radiation therapy for unresectable HCC: The SIRT downstaging study.

BACKGROUND: Selective internal radiation therapy (SIRT) is recommended as a downstaging (DS) strategy for solitary unresectable HCC <8 cm. The aim of this study was to report the results of acquired experience in a tertiary center for all unresectable HCCs. METHODS: We conducted a retrospective, observational study using data collected from consecutive patients undergoing SIRT between October 2013 and June 2020. DS was considered achieved when a curative treatment could be proposed 6 months after SIRT. RESULTS: One hundred twenty-seven patients were included (male = 90%, 64 ± 11 y), of whom 112 (n = 88%) had cirrhosis. HCC was classified as BCLC stage C in 64 patients (50%), with a median diameter of 61 mm, an infiltrative pattern in 51 patients (40%), and portal vein invasion in 62 (49%) patients. Fifty patients (39%) achieved DS 6 months following SIRT, with 29 of them (23%) undergoing curative treatment in a median time of 4.3 months: 17 (13%) were transplanted, 11 (85%) had liver resection, and 1 patient had a radiofrequency ablation. The median overall survival of patients with or without DS was 51 versus 10 months, respectively (p < 0.001). In patients who achieved DS, progression-free survival was higher in patients who underwent surgery: 47 versus 11 months (p < 0.001). Four variables were independently associated with DS: age (OR: 0.96, 95% CI: [0.92, 0.99]; p = 0.032), baseline α-fetoprotein (OR: 1.00, 95% CI: [1.00, 1.00]; p = 0.034), HCC distribution (OR: 0.3, 95% CI: [0.11, 0.75]; p = 0.012), and ALBI grade (OR: 0.34. 95% CI: [0.14, 0.80]; p = 0.014). CONCLUSIONS: These results suggest that SIRT in patients with unresectable HCC could be an effective treatment: DS was achieved for around 39% of the patients and more than half of these then underwent curative treatment.

Iodine Plaque Brachytherapy a Customized Conservative Approach to the Management of Medium/Large-sized Uveal Melanoma.

BACKGROUND/AIM: The objective of this study was to assess the role of iodine (125I) plaque brachytherapy in the management of uveal melanoma. PATIENTS AND METHODS: This is a retrospective study of 50 patients (median age 67 years; range=33-86 years) with uveal melanoma, treated with 125I plaque brachytherapy at the University Hospital of Pisa. Uveal melanoma was diagnosed with A-scan and B-scan standardized echography, fluorescein angiography, indocyanine green-angiography, optical coherence tomography, and/or magnetic resonance imaging. The primary outcomes assessed were local control, overall survival, disease progression, globe preservation, and metastases. Secondary outcomes were acute and late radiation adverse effects. RESULTS: Inclusion criteria comprised Eastern Cooperative Oncology Group performance status ≤2, life expectancy >6 months, and tumor thickness ≤10 mm and\or diameter ≤20 mm. All the patients were treated with 125I plaque brachytherapy, with a prescription dose of 85 Gy to the tumor apex. The 5-year rate of local control, progression-free survival, metastasis-free survival, enucleation-free survival, and overall survival were 83.0%, 81.4%, 90.3%, 83.1%, and 92.1% respectively. Twenty-four patients (48.0%) had one or more acute and late toxicities. The most common acute adverse events (CTCAE vs. 5.0) grade 1-3 were conjunctivitis and eye pain (6.0%). Regarding late events, radiation retinopathy grade 1-3 occurred in 18.0% of cases, while grade 1-3 vitreous hemorrhage in 2.5%. CONCLUSION: 125I plaque brachytherapy offers an effective and safe approach for selected cases of uveal melanoma, due to the reported satisfactory results in terms of local control, eye conservation and survival.

Clinical efficacy and prognostic factors of CT-guided radioactive iodine-125 seed implantation for the treatment of superficial soft tissue metastasis: a 12-year retrospective analysis.

BACKGROUND: Superficial soft tissue metastasis (S-STM) of malignant tumors is uncommon and often brings great pain to patients. However, current treatment options are limited. The purpose of this study was to explore the clinical efficacy and prognostic factors of CT-guided radioactive iodine-125 (125I) seed implantation (RISI) for the treatment of S-STM. METHODS: We retrospectively evaluated 132 patients with S-STM who received RISI between June 2010 and July 2022. Local tumor progression-free survival (ltPFS), tumor response, pain control and complication were analyzed. The independent factors affecting ltPFS were screened out using a layered Cox proportional hazards model. RESULTS: The median follow-up time was 8.3 months (interquartile range [IQR], 4.5-15.3 months). The objective response rate (ORR) was 81.8%. The median ltPFS was 9.1 (95% CI: 6.6, 11.6) months. The Cox proportional hazard regression model revealed that the independent factors influencing ltPFS included KPS score, primary tumor, metastases, boundary, density and postoperative D90 (All P < 0.05). After RISI, the rate of pain relief was 92.3%. 66 (84.6%) patients reported pain marked relief, and 6 (7.7%) experienced pain moderate relief. No severe adverse events associated with RISI were observed during follow-up. CONCLUSIONS: CT-guided RISI was associated with high local control and pain relief without severe adverse events and should be considered as a reliable palliative treatment modality for S-STM. TRIAL REGISTRATION: Trial registration Retrospectively registered.

125I seed brachytherapy for non-central pelvic recurrence of cervical cancer after external beam radiotherapy.

OBJECTIVE: To investigate the efficacy of 125I seed brachytherapy for non-central pelvic recurrence of cervical cancer after external beam radiotherapy, and to analyze the clinical influential factors. METHODS: Between June 2015 and April 2022, 32 patients with 41 lesions were treated with 125I seed brachytherapy. The seeds were implanted under the guidance of CT and/or 3D-printed template images at a median dose of 100 Gy (range, 80-120 Gy), and the local control rate (LCR) and survival rates were calculated. We used multivariate logistic regression to identify prognosis predictors, and receiver operating characteristic (ROC) curve analysis to determine the optimal cut-off values. RESULTS: The median follow-up was 48.52 months (range, 4-86 months), and the 6-, 12-, and 24-month LCR was 88.0%, 63.2%, and 42.1%, respectively. The 1- and 2-year survival rates were 36% and 33%, respectively, and the median survival time was 13.26 months. No significant adverse events occurred. Multivariate regression analysis showed that tumor diameter, tumor stage, and LCR were independent factors influencing survival. ROC curve analysis showed that the area under the curve for tumor diameter and D90 were 0.765 and 0.542, respectively, with cut-off values of 5.3 cm and 108.5 Gy. CONCLUSIONS: The present findings indicate that 125I seed brachytherapy is feasible for treating non-central pelvic recurrence of cervical cancer after external beam radiotherapy. Further, tumor diameter < 5.3 cm and immediate postoperative D90 > 108.5 Gy were associated with better efficacy.

Comparative Single Vesicle Analysis of Aqueous Humor Extracellular Vesicles before and after Radiation in Uveal Melanoma Eyes.

Small extracellular vesicles (sEVs) have been shown to promote tumorigenesis, treatment resistance, and metastasis in multiple cancer types; however, sEVs in the aqueous humor (AH) of uveal melanoma (UM) patients have never previously been profiled. In this study, we used single particle analysis to characterize sEV subpopulations in the AH of UM patients by quantifying their size, concentration, and phenotypes based on cell surface markers, specifically the tetraspanin co-expression patterns of CD9, CD63, and CD81. sEVs were analyzed from paired pre- and post-treatment (brachytherapy, a form of radiation) AH samples collected from 19 UM patients. In post-brachytherapy samples, two subpopulations, CD63/81+ and CD9/63/81+ sEVs, were significantly increased. These trends existed even when stratified by tumor location and GEP class 1 and class 2 (albeit not significant for GEP class 2). In this initial report of single vesicle profiling of sEVs in the AH of UM patients, we demonstrated that sEVs can be detected in the AH. We further identified two subpopulations that were increased post-brachytherapy, which may suggest radiation-induced release of these particles, potentially from tumor cells. Further study of the cargo carried by these sEV subpopulations may uncover important biomarkers and insights into tumorigenesis for UM.

The safety and efficacy of volumetric modulated Arc therapy combined with computer tomography-guided adaptive brachytherapy for locally advanced cervical cancer: a single institution experience.

BACKGROUND: Volumetric modulated arc therapy (VMAT) is a novel form of IMRT, which can deliver more accurate dose distribution and shorten treatment time. Compared to MRI-guided adaptive brachytherapy, which is recommended as gold standard imaging for cervical cancer contours, CT-guided adaptive brachytherapy (CTGAB) is more available, more widespread, and more affordable in many centers. This study aims to retrospectively analyze the efficacy and the safety of VMAT combined with CTGAB for patients with locally advanced cervical cancer. METHODS AND MATERIALS: This study retrospectively analyzed 102 patients with locally advanced cervical cancer who underwent VMAT and CTGAB. Clinical outcomes including local control (LC), overall survival (OS) and progression-free survival (PFS), tumor response to treatment evaluated by the Response Evaluation Criteria in Solid Tumors (RECIST) (version 1.1), and toxicities including gastrointestinal toxicity, urinary toxicity and hematologic toxicity evaluated by the Common Terminology Criteria for Adverse Events (CTCAE) (version 5.0) were analyzed. The Kaplan-Meier method was used to calculate LC, OS, and PFS. RESULTS: Median follow-up time was 19 months. Complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) occurred in 68 (66.7%), 24 (23.5%), 4 (3.92%), and 6 (5.88%), respectively. The 2-year and 3-year OS were 89.6% and 83%, respectively. The 2-year and 3-year PFS were 84.2% and 74.3%, respectively. The 2-year and 3-year LC were 90.1% and 79.3%, respectively. The average cumulative D2cm3 in the rectum, the bladder, the colon, and the small intestine were 78.07 (SD: 0.46) Gy, 93.20 (SD: 0.63) Gy, 63.55 (SD: 1.03) Gy and 61.07 (SD: 0.75) Gy, respectively. The average cumulative D90% of the high-risk clinical target volume (HR-CTV) was 92.26 (SD: 0.35) Gy. Grade ≥ 3 gastrointestinal and urinary toxicities occurred in 4.9% and 0.98%, respectively. 1.96% of patients were observed grade ≥ 4 gastrointestinal toxicities and none of the patients observed grade ≥ 4 urinary toxicities. CONCLUSION: VMAT combined with CTGAB for locally advanced cervical cancer was an effective and safe treatment method, which showed satisfactory LC, OS, PFS, and acceptable toxicities.

Time-resolved clinical dose volume metrics, calculations and predictions based on source tracking measurements and uncertainties to aid treatment verification and error detection for HDR brachytherapy-a proof-of-principle study.

Objective.High-dose-rate (HDR) brachytherapy lacks routinely available treatment verification methods. Real-time tracking of the radiation source during HDR brachytherapy can enhance treatment verification capabilities. Recent developments in source tracking allow for measurement of dwell times and source positions with high accuracy. However, more clinically relevant information, such as dose discrepancies, is still needed. To address this, a real-time dose calculation implementation was developed to provide more relevant information from source tracking data. A proof-of-principle of the developed tool was shown using source tracking data obtained from a 3D-printed anthropomorphic phantom.Approach.Software was developed to calculate dose-volume-histograms (DVH) and clinical dose metrics from experimental HDR prostate treatment source tracking data, measured in a realistic pelvic phantom. Uncertainty estimation was performed using repeat measurements to assess the inherent dose measuring uncertainty of thein vivodosimetry (IVD) system. Using a novel approach, the measurement uncertainty can be incorporated in the dose calculation, and used for evaluation of cumulative dose and clinical dose-volume metrics after every dwell position, enabling real-time treatment verification.Main results.The dose calculated from source tracking measurements aligned with the generated uncertainty bands, validating the approach. Simulated shifts of 3 mm in 5/17 needles in a single plan caused DVH deviations beyond the uncertainty bands, indicating errors occurred during treatment. Clinical dose-volume metrics could be monitored in a time-resolved approach, enabling early detection of treatment plan deviations and prediction of their impact on the final dose that will be delivered in real-time.Significance.Integrating dose calculation with source tracking enhances the clinical relevance of IVD methods. Phantom measurements show that the developed tool aids in tracking treatment progress, detecting errors in real-time and post-treatment evaluation. In addition, it could be used to define patient-specific action limits and error thresholds, while taking the uncertainty of the measurement system into consideration.

Multimodality management of locoregionally extensive Marjolin ulcer: a case report and review of the literature.

BACKGROUND: Marjolin ulcer (MU) is an aggressive cutaneous malignancy that commonly occurs in those with a chronic wound such as post-burn scar. CASE REPORT: A 20-year-old male who sustained a flame burn over the scalp at 3 months of age developed a nonhealing ulcer over the burn scar 20 years later, which was treated with adequate surgical margins with adjuvant mold brachytherapy. Two months after completion of that treatment, he developed parotid nodal metastasis with positron emission tomography (PET)-positive bilateral cervical, supraclavicular, right suboccipital, and mesenteric lymph nodes that were treated with concurrent chemoradiation. One month later, the patient developed an ulcerative lesion involving the left parotid region with PET showing infiltration of the parotid gland, but with resolution of other previous sites of uptake. The patient was treated surgically with radical parotidectomy with elective neck dissection and reconstruction with locoregional flap. At 6-month follow-up, the patient developed extensive locoregional recurrence and distant metastasis and was started on oral metronomic therapy. The patient was alive with stable disease at 3-month follow-up after initiation of palliative chemotherapy. CONCLUSION: Despite timely multimodality therapy, MU may present with a hostile clinical course with a short disease-free interval and early recurrence.

A prostate seed implantation robot system based on human-computer interactions: Augmented reality and voice control.

The technology of robot-assisted prostate seed implantation has developed rapidly. However, during the process, there are some problems to be solved, such as non-intuitive visualization effects and complicated robot control. To improve the intelligence and visualization of the operation process, a voice control technology of prostate seed implantation robot in augmented reality environment was proposed. Initially, the MRI image of the prostate was denoised and segmented. The three-dimensional model of prostate and its surrounding tissues was reconstructed by surface rendering technology. Combined with holographic application program, the augmented reality system of prostate seed implantation was built. An improved singular value decomposition three-dimensional registration algorithm based on iterative closest point was proposed, and the results of three-dimensional registration experiments verified that the algorithm could effectively improve the three-dimensional registration accuracy. A fusion algorithm based on spectral subtraction and BP neural network was proposed. The experimental results showed that the average delay of the fusion algorithm was 1.314 s, and the overall response time of the integrated system was 1.5 s. The fusion algorithm could effectively improve the reliability of the voice control system, and the integrated system could meet the responsiveness requirements of prostate seed implantation.

Intermediate-risk endometrial cancer treated with adjuvant brachytherapy using single dosimetric planning: long-term outcome and toxicity assessment.

OBJECTIVE: Brachytherapy of the vaginal dome is the recommended adjuvant treatment for intermediate-risk endometrial cancer. This study assessed the results of dosimetric planning of high-dose-rate brachytherapy exclusively in the first treatment session. STUDY DESIGN: This retrospective study included all patients who underwent hysterectomy for endometrial cancer followed by adjuvant brachytherapy of the vaginal dome between 2012 and 2015. Local recurrence rates, overall survival (OS) rates, recurrence-free survival (RFS) rates, and related acute and late toxicity rates were evaluated. RESULTS: This analysis included 250 patients, of whom 208 were considered to be at high-intermediate risk of disease recurrence. After a median follow-up of 56 months, the cumulative incidence of local recurrence was 4.8% at 3 years [95% confidence interval (CI) 2.8-8.3] and 7.8% at 5 years (95% CI 4.8-12.6). The 5-year OS rate was 86.2% (95% CI 80.6-90.3), and the 5-year RFS rate was 77.5% (95% CI 71.1-82.7). Acute toxicity occurred in 20 (8%) patients, of which two patients had grade ≥3 toxicity. Only one patient (0.4%) presented with late grade ≥3 toxicity. CONCLUSION: These findings confirm the tolerability of this brachytherapy approach, indicating minimal cases of late grade ≥3 toxicity, associated with a good 5-year OS rate. With the advent of molecular prognostic factors, the current focus revolves around discerning those individuals who gain the greatest benefit from adjuvant therapy, and tailoring treatment more effectively.

A survey on brachytherapy training of gynecological cancer focusing on the competence of residents in China.

BACKGROUND: The brachytherapy is an indispensable treatment for gynecological tumors, but the quality and efficiency of brachytherapy training for residents is still unclear. METHODS: An anonymous questionnaire was designed to collect information on gynecological brachytherapy (GBT) training for radiation oncology residents from 28 training bases in China. The questionnaire content was designed based on the principle of competency based medical education (CBME). The Likert scale was employed to evaluate self-reported competence and comprehension regarding GBT. A total of 132 senior residents were included in the final analysis. RESULTS: 53.79% (71/132) of senior residents had experience in performing image-guided GBT, whereas 76.52% (101/132) had observed the procedure during their standardized residency training. The proportion of senior residents who reported having the self-reported competence to independently complete the GBT was 78.03% for intracavity GBT, 75.00% for vaginal stump GBT, and 50.03% for interstitial GBT, respectively. The number of successful completion of Interstitial, intracavity and vaginal GBT was correlated with the self- confidence of trainees after standardized training. In particular, the independent completion of interstitial GBT for more than 20 cases was an independent factor for the self-reported competence of senior residents. During the training period, 50.76% and 56.82% of the residents had not participated in the specialized examinations and professional GBT courses. CONCLUSIONS: The study revealed that the self-confidence of residents to independently complete brachytherapy was relatively high, and the specialized curriculum setting and training process assessment for brachytherapy training still need to be strengthened in the future.

Interventional radiotherapy (brachytherapy) for re-irradiation of recurrent head and neck malignancies: oncologic outcomes and morbidity.

Objective: Management of recurrent head and neck cancer (HNC) is challenging. One option in previously irradiated patients is re-irradiation using interventional radiotherapy (IRT), the modern form of brachytherapy. Re-irradiation using IRT can be delivered as an exclusive strategy for salvage or through a postoperative or perioperative approach after salvage surgery. The aim of the present study is to analyse a bicentric Italian series focusing on the use of IRT as a re-irradiation modality and assess the resulting evidence concerning oncologic outcomes and morbidity. Methods: This is a retrospective study performed in two referral centres in Italy: Policlinico Universitario Agostino Gemelli in Rome and Azienda Ospedaliera Universitaria in Sassari. All patients who had previously received a full course of external beam RT and have been re-irradiated using high-dose-rate IRT between December 2010 and June 2023 were included. Patients were retreated either by a combination of surgery and perioperative (either endocavitary or interstitial) IRT or by exclusive interstitial IRT. Results: Thirty-four patients were included in the present series, 2 of whom underwent more than one IRT re-irradiation. Notably, no patient reported specific IRT-related toxicities. Median follow-up, excluding patients who died of HNC, was 24.5 months. Two-year local relapse-free survival was 26%, disease-specific survival 39.1%, and overall survival 36.6%. Conclusions: The present series is the largest reported experience of re-irradiation by IRT for HNC in Italy. The very low rate of toxicity confirms IRT as the safest re-irradiation modality. It is noteworthy to underline that IRT is a multidisciplinary strategy based on the close cooperation between surgeons and radiation oncologists during every phase, from the recommendation of treatment and implantation in the operating theatre, to its prescription and dose painting.

An evaluation of consumer smartphones for generating bolus and surface mould applicators for radiation oncology.

BACKGROUND: The use of Computed Tomography (CT) imaging data to create 3D printable patient-specific devices for radiation oncology purposes is already well established in the literature and has shown to have superior conformity than conventional methods. Using non-ionizing radiation imaging techniques such as photogrammetry or laser scanners in-lieu of a CT scanner presents many desirable benefits including reduced imaging dose and fabrication of the device can be completed prior to simulation. With recent advancements in smartphone-based technology, photographic and LiDAR-based technologies are more readily available than ever before and to a high level of quality. As a result, these non-ionizing radiation imaging methods are now able to generate patient-specific devices that can be acceptable for clinical use. PURPOSE: In this work, we aim to determine if smartphones can be used by radiation oncologists or other radiation oncology staff to generate bolus or brachytherapy surface moulds instead of conventional CT with equivalent or comparable accuracy. METHODS: This work involved two separate studies: a phantom and participant study. For the phantom study, a RANDO anthropomorphic phantom (limited to the nose region) was used to generate 3D models based on three different imaging techniques: conventional CT, photogrammetry & LiDAR which were both acquired on a smartphone. Virtual boli were designed in Blender and 3D printed from PLA plastic material. The conformity of each printed boli was assessed by measuring the air gap volume and approximate thickness between the phantom & bolus acquired together on a CT. For the participant study, photographs, and a LiDAR scan of four volunteers were captured using an iPhone 13 Pro™ to assess their feasibility for generating human models. Each virtual 3D model was visually assessed to identify any issues in their reconstruction. The LiDAR models were registered to the photogrammetry models where a distance to agreement analysis was performed to assess their level of similarity. Additionally, a 3D virtual bolus was designed and printed using ABS material from all models to assess their conformity onto the participants skin surface using a verbal feedback method. RESULTS: The photogrammetry derived bolus showed comparable conformity to the CT derived bolus while the LiDAR derived bolus showed poorer conformity as shown by their respective air gap volume and thickness measurements. The reconstruction quality of both the photogrammetry and LiDAR models of the volunteers was inadequate in regions of facial hair and occlusion, which may lead to clinically unacceptable patient-specific device that are created from these areas. All participants found the photogrammetry 3D printed bolus to conform to their nose region with minimal room to move while three of the four participants found the LiDAR was acceptable and could be positioned comfortably over their entire nose. CONCLUSIONS: Smartphone-based photogrammetry and LiDAR software show great potential for future use in generating 3D reference models for radiation oncology purposes. Further investigations into whether they can be used to fabricate clinically acceptable patient-specific devices on a larger and more diverse cohort of participants and anatomical locations is required for a thorough validation of their clinical usefulness.

AAPM Task Group Report 267: A joint AAPM GEC-ESTRO report on biophysical models and tools for the planning and evaluation of brachytherapy.

Brachytherapy utilizes a multitude of radioactive sources and treatment techniques that often exhibit widely different spatial and temporal dose delivery patterns. Biophysical models, capable of modeling the key interacting effects of dose delivery patterns with the underlying cellular processes of the irradiated tissues, can be a potentially useful tool for elucidating the radiobiological effects of complex brachytherapy dose delivery patterns and for comparing their relative clinical effectiveness. While the biophysical models have been used largely in research settings by experts, it has also been used increasingly by clinical medical physicists over the last two decades. A good understanding of the potentials and limitations of the biophysical models and their intended use is critically important in the widespread use of these models. To facilitate meaningful and consistent use of biophysical models in brachytherapy, Task Group 267 (TG-267) was formed jointly with the American Association of Physics in Medicine (AAPM) and The Groupe Européen de Curiethérapie and the European Society for Radiotherapy & Oncology (GEC-ESTRO) to review the existing biophysical models, model parameters, and their use in selected brachytherapy modalities and to develop practice guidelines for clinical medical physicists regarding the selection, use, and interpretation of biophysical models. The report provides an overview of the clinical background and the rationale for the development of biophysical models in radiation oncology and, particularly, in brachytherapy; a summary of the results of literature review of the existing biophysical models that have been used in brachytherapy; a focused discussion of the applications of relevant biophysical models for five selected brachytherapy modalities; and the task group recommendations on the use, reporting, and implementation of biophysical models for brachytherapy treatment planning and evaluation. The report concludes with discussions on the challenges and opportunities in using biophysical models for brachytherapy and with an outlook for future developments.

Carbon ion radiotherapy for mesonephric adenocarcinoma of the uterine cervix: a case report.

BACKGROUND: Mesonephric adenocarcinoma is an extremely rare subtype of uterine cervical cancer that is associated with a poor prognosis and for which a standardized treatment protocol has not been established. Carbon ion radiotherapy (CIRT) is an emerging radiotherapy modality that has been shown to have a favorable anti-tumor effect, even for tumors resistant to conventional photon radiotherapy or chemotherapy. However, there is no report on CIRT outcomes for mesonephric adenocarcinoma of the uterine cervix. CASE PRESENTATION: We treated a 47-year-old Japanese woman with mesonephric adenocarcinoma of the uterine cervix (T2bN0M0 and stage IIB according to the 7th edition of the Union for International Cancer Control and International Federation of Gynecology and Obstetrics, respectively) with CIRT combined with brachytherapy and concurrent chemotherapy. CIRT consisted of whole pelvic irradiation and boost irradiation to the gross tumor; 36.0 Gy (relative biological effectiveness [RBE]) in 12 fractions and 19.2 Gy (RBE) in 4 fractions, respectively, performed once a day, four times per week. Computed tomography-based image-guided adaptive brachytherapy was performed after completion of CIRT, for which the D90 (i.e., the dose prescribed to 90% of the target volume) for the high-risk clinical target volume was 20.4 Gy in a total of 3 sessions in 2 weeks. A weekly cisplatin (40 mg/m2) dose was administered concomitantly with the radiotherapy for a total of five courses. From 4 months post-CIRT, the patient developed metastasis of the lung, with a total of 10 lung metastases over 70 months; these lesions were treated on each occasion by photon stereotactic body radiotherapy and/or systemic therapy. At 8 years from initial treatment (i.e., 2 years after the last treatment), the patient is alive without any evidence of recurrence and maintains a high quality of life. CONCLUSIONS: This is the first report of CIRT for treatment of mesonephric adenocarcinoma of the uterine cervix. The present case indicates the potential efficacy of CIRT in combination with brachytherapy for treatment of this disease.

[Predicting the effectiveness of organ-preserving treatment of choroidal melanoma using optical coherence tomography data]. / Prognozirovanie effektivnosti organosokhrannogo lecheniya melanomy khorioidei po dannym opticheskoi kogerentnoi tomografii.

Optical coherence tomography (OCT) is currently widely used for the diagnosis of choroidal melanoma (CM), but the problem of predicting the outcomes of planned CM treatment remains unsolved. PURPOSE: This study was conducted to identify OCT signs that adversely affect the outcome of organ-preserving CM treatment. MATERIAL AND METHODS: OCT scan images of 30 patients who underwent organ-preserving treatment and were under observation were selected for this study. Brachytherapy (BT) as monotherapy was performed in 27 patients (in 2 cases - twice, and in 1 case - three times), in one patient - in combination with the previous transpupillary thermotherapy (TTT). Multiple TTT (4 sessions within 4 months) as monotherapy were performed in 2 patients. In 9 cases, a single organ-preserving treatment (BT - 6 patients, TTT - 3 patients) was ineffective. In these cases, the effectiveness of the first stage of organ-preserving treatment was taken into account. RESULTS: Seven signs of an unfavorable prognosis of the performed treatment were identified by analyzis of tomograms and statistical processing of the obtained data. These signs include: the presence of intraretinal edema, detachment of the neuroepithelium (NED) over the tumor, including with a break in the photoreceptors, accumulation of transudate over the tumor, the presence of large cysts, intraretinal cavities and NED near the tumor (secondary retinal detachment). A combination of three or more signs were observed in all cases of inefficiency of the first stage of treatment. Most often, intraretinal edema and NED over the tumor were combined with the accumulation of subretinal transudate and NED near the tumor. The presence of 6 or all 7 signs took place in cases of a negative therapeutic effect after local destruction. CONCLUSION: When planning organ-preserving CM treatment, in addition to biometric parameters, it is necessary to pay special attention to the identification of such morphological signs as NED over and near the tumor, accumulation of transudate under the NED, the presence of intraretinal edema, large intraretinal cysts and cavities.

Dose and DNA damage modelling of diffusing alpha-emitters radiation therapy using Geant4.

PURPOSE: Diffusing alpha-emitters radiation therapy (DaRT) is a brachytherapy technique using α-particles to treat solid tumours. The high linear energy transfer (LET) and short range of α-particles make them good candidates for the targeted treatment of cancer. Treatment planning of DaRT requires a good understanding of the dose from α-particles and the other particles released in the 224Ra decay chain. METHODS: The Geant4 Monte Carlo toolkit has been used to simulate a DaRT seed to better understand the dose contribution from all particles and simulate the DNA damage due to this treatment. RESULTS: Close to the seed α-particles deliver the majority of dose, however at radial distances greater than 4 mm, the contribution of ß-particles is greater. The RBE has been estimated as a function of number of double strand breaks (DSBs) and complex DSBs. A maximum seed spacing of 5.5 mm and 6.5 mm was found to deliver at least 20 Gy RBE weighted dose between the seeds for RBEDSB and RBEcDSB respectively. CONCLUSIONS: The DNA damage changes with radial distance from the seed and has been found to become less complex with distance, which is potentially easier for the cell to repair. Close to the seed α-particles contribute the majority of dose, however the contribution from other particles cannot be neglected and may influence the choice of seed spacing.

Experimental validation of the accuracy of robotic-assisted radioactive seed implantation for tumor treatment.

An experimental validation of a robotic system for radioactive iodine-125 seed implantation (RISI) in tumor treatment was conducted using customized phantom models and animal models simulating liver and lung lesions. The robotic system, consisting of planning, navigation, and implantation modules, was employed to implant dummy radioactive seeds into the models. Fiducial markers were used for target localization. In phantom experiments across 40 cases, the mean errors between planned and actual seed positions were 0.98 ± 1.05 mm, 1.14 ± 0.62 mm, and 0.90 ± 1.05 mm in the x, y, and z directions, respectively. The x, y, and z directions correspond to the left-right, anterior-posterior, and superior-inferior anatomical planes. Silicone phantoms exhibiting significantly smaller x-axis errors compared to liver and lung phantoms (p < 0.05). Template assistance significantly reduced errors in all axes (p < 0.05). No significant dosimetric deviations were observed in parameters such as D90, V100, and V150 between plans and post-implant doses (p > 0.05). In animal experiments across 23 liver and lung cases, the mean implantation errors were 1.28 ± 0.77 mm, 1.66 ± 0.69 mm, and 1.86 ± 0.93 mm in the x, y, and z directions, slightly higher than in phantoms (p < 0.05), with no significant differences between liver and lung models. The dosimetric results closely matched planned values, confirming the accuracy of the robotic system for RISI, offering new possibilities in clinical tumor treatment.

[Brachytherapy : a crucial part of locally advanced cervical cancer treatment]. / La curiethérapie : un atout majeur dans le traitement du cancer du col de l'utérus localement avancé.

Cervical cancer is the 4th most diagnosed cancer in women. At a locally advanced stage, standard treatment combines chemotherapy, radiotherapy and a brachytherapy boost. Brachytherapy is a radiotherapy modality, often unknown, which allows the delivery of a very targeted high dose because it's given directly in contact with the tumor. This technique has proven its effectiveness in the treatment of locally advanced cervical cancer. It represents a major advantage because, despite technical advances, there is currently no alternative yielding equivalent results.

Le cancer du col utérin est le 4ème cancer féminin le plus diagnostiqué. à un stade localement avancé, la prise en charge standard relève d'un traitement associant de la chimiothérapie, de la radiothérapie et une curiethérapie de clôture. La curiethérapie est une modalité de radiothérapie, souvent méconnue du grand public, qui permet de délivrer une dose élevée de façon très ciblée, car celle-ci est donnée directement au contact de la tumeur. Cette technique a prouvé son efficacité et son caractère indispensable dans le traitement du cancer du col utérin localement avancé. Elle représente un atout majeur car, malgré l'évolution des techniques de radiothérapie externe plus modernes, il n'y a, à ce jour, aucune alternative équivalente.