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Background Radiotherapy is a standard treatment for locally advanced cervical cancer. Based on the inherent characteristics of X-ray and γ-ray radiation techniques, we propose and investigate an innovative dual-modality radiation system incorporating both X-ray and γ-ray modalities. This study compares the quality of radiation treatment plans for patients with CC, generated using the dual-modality (TaiChi) system and a conventional LINAC X-ray system. Methods Retrospective treatment plans using volumetric modulated arc therapy were selected for 12 patients with CC. Dual-modality plans were developed for these patients. All patients had the same prescription dose of 50 Gy/25 fractions for planning tumor volume (PTV) and 60 Gy/25 fractions for PTV-nd. The dose conformity index (CI) and gradient index (GI) were calculated to evaluate the dose coverage and drop for the target. The dose indices, Dmean, Dmax, and Dmin, were calculated for both the target and organs at risk (OARs). Results Both strategies generated dosimetrically acceptable plans. For both PTV-nd and PTV, the plans of TaiChi demonstrated higher CI values (PTV-nd: 0.68 ± 0.11 vs. 0.57 ± 0.22, P-value  = 0.1375; PTV: 0.91 ± 0.02 vs. 0.90 ± 0.02, P-value  = 0.1053) and lower GI values (PTV-nd: 280.62 ± 302.86 vs. 300.65 ± 317.83, P -value = 0.0094; PTV: 3.36 ± 0.22 vs. 3.66 ± 0.32, P-value  = 0.0015) compared with the plans of the conventional LINAC system. For both PTV-nd and PTV, the TaiChi plans exhibited superior dosimetric indices compared to the LINAC plans. Specifically, the Dmax (78.27±5.20 Gy vs. 66.61±1.51 Gy) and Dmean (66.85±1.61 Gy vs. 63.22±1.03 Gy) of the TaiChi plans were significantly higher than those of the LINAC plans. Although the Dmin (61.06±0.52 Gy vs. 60.46±1.33 Gy) of the TaiChi plans was also higher than that of the LINAC plans, the difference was not statistically significant. Moreover, TaiChi plans significantly reduced radiation exposure to OARs compared to LINAC plans, demonstrating improved organ protection. This was particularly evident for the spinal cord PRV, with the TaiChi plans yielding a maximum dose of 23.61±2.80 Gy, compared to 29.85±3.23 Gy for the LINAC plans ( P -value = 0.0005). Conclusions The dual-modality system has the potential to enhance treatment outcomes in CC by optimizing tumor coverage while reducing toxicity. Future clinical trials should assess its impact on patient survival and treatment-related side effects to bridge the gap between dosimetric improvements and clinical application.

Radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) is the cornerstone of organ-sparing or adjuvant therapy for nearly all head and neck cancers. Unfortunately, aggressive RT or CCRT can result in severe late toxicities, such as osteoradionecrosis of the jaws (ORNJ). The incidence of ORNJ is currently less than 5–6% due to advances in dental preventive care programs, RT planning systems, and RT techniques. Although numerous patient-, tumor-, and treatment-related factors may influence the incidence rates of ORNJ, RT modality (equipment), technique, and dose-volume-related factors are three of the most influential factors. This is mainly because different RT equipment and techniques have different levels of success at delivering the prescribed dose to the focal volume of the treatment while keeping the “organ at risk” safe. ORNJ risk is ultimately determined by mandibular dose, despite the RT technique and method being known predictors. Regardless of the photon delivery method, the radiobiological effects will be identical if the total dose, dose per fraction, and dose distribution within the tissue remain constant. Therefore, contemporary RT procedures mitigate this risk by reducing mandibular dosages rather than altering the ionizing radiation behavior in irradiated tissues. In light of the paucity of studies that have examined the impact of RT modality, technique, and dose-volume-related parameters, as well as their radiobiological bases, the present review aims to provide a comprehensive overview of the published literature on these specific issues to establish a common language among related disciplines and provide a more reliable comparison of research results.

Objective This study aimed to explore the influencing factors of survival benefit and poor prognosis of cervical cancer patients under different radiotherapy modalities. Methods A total of 186 patients with cervical cancer treated in our hospital from January 2022 to December 2023 were selected for the retrospective analysis. 126 patients received static intensity-modulated radiation therapy (IMRT) combined with cisplatin. Another 60 cases received volumetric modulated arc therapy (VMAT) combined with cisplatin. The occurrence of adverse reactions, overall survival rate, and recurrence rate were compared between the two groups. COX regression model was used to analyze the influencing factors of the poor prognosis. Results There was no difference between the disease control rate (DCR) and objective remission rate (ORR), and the overall survival and recurrence rates in the two groups. The incidence of myelosuppression was much higher in the IMRT group than the VMAT group. Compared with the survival group, the percentage of lymph node metastasis (LNM) and positive margins were significantly increased in the patients in the death group. COX multifactorial analysis confirmed that LNM and positive cutting margins were independent risk factors affecting poor prognosis after radiotherapy in cervical cancer patients ( P  < 0.05). Conclusion Both IMRT and VMAT could achieve certain effects in the treatment of cervical cancer and had similar effects in short-term survival recurrence. However, VMAT had a lower incidence of myelosuppression. LNM and positive margins were factors influencing the poor prognosis of patients.

TaiChi, a new multi-modality radiotherapy platform that integrates a linear accelerator, a focusing gamma system, and a kV imaging system within an enclosed O-ring gantry, was introduced into clinical application. This work aims to assess the technological characteristics and commissioning results of the TaiChi platform. The acceptance testing and commissioning were performed following the manufacturer’s customer acceptance tests (CAT) and several AAPM Task Group (TG) reports/guidelines. Regarding the linear accelerator (linac), all applicable validation measurements recommended by the MPPG 5.a (basic photon beam model validation, intensity-modulated radiotherapy (IMRT)/volumetric-modulated arc therapy (VMAT) validation, end-to-end(E2E) tests, and patient-specific quality assurance (QA)) were performed. For the focusing gamma system, the absorbed doses were measured using a PTW31014 ion chamber (IC) and PTW60016 diode detector. EBT3 films and a PTW60016 diode detector were employed to measure the relative output factors (ROFs). The E2E tests were performed using PTW31014 IC and EBT3 films. The coincidences between the imaging isocenter and the linac/gamma mechanical isocenter were investigated using EBT3 films. The image quality was evaluated regarding the contrast-to-noise ratio (CNR), spatial resolution, and uniformity. All tests included in the CAT met the manufacturer’s specifications. All MPPG 5.a measurements complied with the tolerances. The confidence limits for IMRT/VMAT point dose and dose distribution measurements were achieved according to TG-119. The point dose differences were below 1.68% and gamma passing rates (3%/2 mm) were above 95.1% for the linac E2E tests. All plans of patient-specific QA had point dose differences below 1.79% and gamma passing rates above 96.1% using the 3%/2 mm criterion suggested by TG-218. For the focusing gamma system, the differences between the calculated and measured absorbed doses were below 1.86%. The ROFs calculated by the TPS were independently confirmed within 2% using EBT3 films and a PTW60016 detector. The point dose differences were below 2.57% and gamma passing rates were above 95.3% using the 2%/1 mm criterion for the E2E tests. The coincidences between the imaging isocenter and the linac/gamma mechanical isocenter were within 0.5 mm. The image quality parameters fully complied with the manufacturer’s specifications regarding the CNR, spatial resolution, and uniformity. The multi-modality radiotherapy platform complies with the CAT and AAPM commissioning criteria. The commissioning results demonstrate that this platform performs well in mechanical and dosimetry accuracy.

Background Possible advantages of magnetic resonance (MR)-guided radiation therapy (MRgRT) for the treatment of brain tumors include improved definition of treatment volumes and organs at risk (OARs) that could allow margin reductions, resulting in limited dose to the OARs and/or dose escalation to target volumes. Recently, hybrid systems integrating a linear accelerator and an magnetic resonance imaging (MRI) scan (MRI-linacs, MRL) have been introduced, that could potentially lead to a fully MRI-based treatment workflow. Methods We performed a systematic review of the published literature regarding the adoption of MRL for the treatment of primary or secondary brain tumors (last update November 3, 2022), retrieving a total of 2487 records; after a selection based on title and abstracts, the full text of 74 articles was analyzed, finally resulting in the 52 papers included in this review. Results and discussion Several solutions have been implemented to achieve a paradigm shift from CT-based radiotherapy to MRgRT, such as the management of geometric integrity and the definition of synthetic CT models that estimate electron density. Multiple sequences have been optimized to acquire images with adequate quality with on-board MR scanner in limited times. Various sophisticated algorithms have been developed to compensate the impact of magnetic field on dose distribution and calculate daily adaptive plans in a few minutes with satisfactory dosimetric parameters for the treatment of primary brain tumors and cerebral metastases. Dosimetric studies and preliminary clinical experiences demonstrated the feasibility of treating brain lesions with MRL. Conclusions The adoption of an MRI-only workflow is feasible and could offer several advantages for the treatment of brain tumors, including superior image quality for lesions and OARs and the possibility to adapt the treatment plan on the basis of daily MRI. The growing body of clinical data will clarify the potential benefit in terms of toxicity and response to treatment.

Purpose: To investigate and compare 2 cone-beam computed tomography (CBCT) correction methods for CBCT-based dose calculation. Materials and Methods: Routine CBCT image sets of 12 head and neck cancer patients who received volumetric modulated arc therapy (VMAT) treatment were retrospectively analyzed. The CBCT images obtained using an on-board imager (OBI) at the first treatment fraction were firstly deformable registered and padded with the kVCT images to provide enough anatomical information about the tissues for dose calculation. Then, 2 CBCT correction methods were developed and applied to correct CBCT Hounsfield unit (HU) values. One method (HD method) is based on protocol-specific CBCT HU to physical density (HD) curve, and the other method (HM method) is based on histogram matching (HM) of HU value. The corrected CBCT images (CBCTHD and CBCTHM for HD and HM methods) were imported into the original planning system for dose calculation based on the HD curve of kVCT (the planning CT). The dose computation result was analyzed and discussed to compare these 2 CBCT-correction methods. Results: Dosimetric parameters, such as the Dmean, Dmax and D5% of the target volume in CBCT plan doses, were higher than those in the kVCT plan doses; however, the deviations were less than 2%. The D2%, in parallel organs such as the parotid glands, the deviations from the CBCTHM plan dose were less than those of the CBCTHD plan dose. The differences were statistically significant (P < .05). Meanwhile, the V30 value based on the HM method was better than that based on the HD method in the oral cavity region (P = .016). In addition, we also compared the γ passing rates of kVCT plan doses with the 2 CBCT plan doses, and negligible differences were found. Conclusion: The HM method was more suitable for head and neck cancer patients than the HD one. Furthermore, with the CBCTHM-based method, the dose calculation result better matches the kVCT-based dose calculation.

Purpose: During ultrasound (US)-guided radiotherapy, the tissue is deformed by probe pressure, and the US image is limited by changes in tissue and organ position and geometry when the US image is aligned with computed tomography (CT) image, leading to poor alignment. Accordingly, a pixel displacement-based nondeformed US image production method is proposed. Methods: The correction of US image deformation is achieved by calculating the pixel displacement of an image. The positioning CT image (CTstd) is used as the gold standard. The deformed US image (USdef) is inputted into the Harris algorithm to extract corner points for selecting feature points, and the displacement of adjacent pixels of feature points in the US video stream is calculated using the Lucas-Kanade optical flow algorithm. The moving least squares algorithm is used to correct USdef globally and locally in accordance with image pixel displacement to generate a nondeformed US image (USrev). In addition, USdef and USrev were separately aligned with CTstd to evaluate the improvement of alignment accuracy through deformation correction. Results: In the phantom experiment, the overall and local average correction errors of the US image under the optimal probe pressure were 1.0944 and 0.7388 mm, respectively, and the registration accuracy of USdef and USrev with CTstd was 0.6764 and 0.9016, respectively. During the volunteer experiment, the correction error of all 12 patients’ data ranged from −1.7525 to 1.5685 mm, with a mean absolute error of 0.8612 mm. The improvement range of US and CT registration accuracy, before and after image deformation correction in the 12 patients evaluated by a normalized correlation coefficient, was 0.1232 to 0.2476. Conclusion: The pixel displacement-based deformation correction method can solve the limitation imposed by image deformation on image alignment in US-guided radiotherapy. Compared with USdef, the alignment results of USrev with CT were better.

Zusammenfassung Hintergrund Die Strahlentherapie wird als lokale Therapiemaßnahme in kurativen oder palliativen interdisziplinären Konzepten zur Behandlung des malignen Melanoms eingesetzt. Ziel der Arbeit Ziel war die Darstellung des aktuellen Stellenwerts strahlentherapeutischer Modalitäten bei verschiedenen Indikationen in der Behandlung des Melanoms. Material und Methoden In der Form einer narrativen Übersicht wurden relevante Publikationen zu den Behandlungsergebnissen der Strahlentherapie zusammengefasst. Ergebnisse Durch die postoperative Strahlentherapie des Lymphabflussgebiets bei Vorliegen definierter Risikofaktoren verbessert sich die regionäre Tumorkontrolle. Die palliative Radiotherapie reduziert die Symptombelastung bei extrakraniellen Fernmetastasen, insbesondere bei Knochenmetastasen. Mit der stereotaktischen Bestrahlung von Hirnmetastasen oder postoperativ der Resektionshöhle werden hohe lokale Kontrollraten erreicht. Schlussfolgerung Die moderne Strahlentherapie leistet situtationsabhängig einen wichtigen Beitrag zu multimodalen Behandlungskonzepten des Melanoms.

This study aims to investigate the effect of different local testicular treatments and validate common prognostic factors on primary testicular lymphoma (PTL) patients. We retrospectively reviewed the clinical records of 32 patients from 1993 to 2017 diagnosed with PTL and included 22 patients for analysis. The Kaplan-Meier method, Log-rank test, and multivariate Cox proportional hazard regression analysis were applied to evaluate progression-free survival (PFS), overall survival (OS), and determine prognosis predictors. The median follow-up time was 30 months. Median OS and PFS were 96 months and 49 months, respectively. In univariate analysis, advanced Ann Arbor stage (III/IV) (P < 0.001), B symptoms (P < 0.001), and extranodal involvement other than testis (P = 0.001) were significantly associated with shorter OS and PFS. In multivariate analysis, Ann Arbor stage was significantly associated with OS (OR = 11.58, P = 0.049), whereas B symptom was significantly associated with PFS (OR = 11.79, P= 0.049). In the 10 patients with the systemic usage of rituximab, bilateral intervention could improve median OS from 16 to 96 months (P = 0.032). The study provides preliminary evidence on bilateral intervention in testes in the rituximab era and validates common prognostic factors for Chinese PTL patients.

In this study, irradiation of the internal mammary and medial supraclavicular nodes plus whole breast or thoracic-wall radiation therapy in women with localized breast cancer was linked to increased disease-free survival but only a marginal gain in overall survival. The first filter stations for the lymphatic drainage of the breast are the axillary and internal mammary lymph nodes. 1 Surgical studies have shown that the incidence of metastatic involvement of the internal mammary nodes varies between 4% and 9% in patients with axillary node–negative breast cancer and between 16% and 65% in patients with axillary node–positive breast cancer. 2 – 4 As a consequence, surgical dissection of the internal mammary nodes was attempted but abandoned in the 1970s, since no improvement in survival was observed. 4 , 5 Elective irradiation of the regional nodes remained widely used until the late 1980s, when it became . . .