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Simple Summary: The effects of reduced prescription doses on normal tissue toxicity in the treatment of non-Hodgkin lymphomas of the neck/thorax region remain unclear. Acute side effects, which already occur at low organ doses, can only be described to a limited extent by the models given in the literature. Nonetheless, the knowledge about these dose–response relationships is particularly important to predict an acute response in normal tissue adequately. Considering a robust normal tissue toxicity model, dose prescriptions and treatment plans can be optimized to increase the treatment quality and, thus, the outcome for the patient. This biophysical study aimed to determine fitting parameters for the Lyman–Kutcher–Burman (LKB) dose–response model for normal tissue complication probability (NTCP) calculations of acute side effects and to investigate the impact of reduced radiation doses on the probability of their occurrence in supradiaphragmatic non-Hodgkin lymphoma (NHL) irradiation. A cohort of 114 patients with NHL in the cervicothoracic region, treated between 2015 and 2021 at the University Hospitals of Münster, Hamburg, and Essen, with involved site radiation therapy (ISRT), were included. Among them, 68 patients with aggressive NHL (a-NHL) received consolidative radiation therapy with 24–54 Gy following (R-)CHOP chemotherapy. Additionally, 46 patients with indolent NHL (i-NHL) underwent radiotherapy with 22.5–45.0 Gy. Two treatment plans were prospectively created for each patient (a-NHL: 30.0/40.0 Gy; i-NHL: 24.0/30.0 Gy). NTCP were then calculated using the optimized LKB model. The adapted dose–response models properly predicted the patient's probability of developing acute side effects when receiving doses ≤ 50 Gy. In addition, it was shown that reduced radiation doses can influence the NTCP of acute side effects depending on the aggressiveness of NHL significantly. This study provided a foundation to prospectively assess the probability of adverse side effects among today's reduced radiation doses in the treatment of NHL. [ABSTRACT FROM AUTHOR]

Copyright of Strahlentherapie und Onkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Strahlentherapie und Onkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Patients with adenoid cystic carcinoma (ACC) of the salivary glands in the head and neck region have been reported to benefit from neutron radiotherapy according to significant clinical experience. A prospective clinical trial on the efficacy and treatment related morbidity of fast neutron radiotherapy was performed between 1986 and 1995 at the (d + T) 14 MeV neutron generator in Münster.Material and Methods: 72 consecutive patients with ACC were treated with fast neutrons, 66 after surgery, 6 for primarily unresectable disease, 43/66 for macroscopic residual disease, 23/66 for unresectable recurrent disease. 45/72 tumors were localized in the minor, 27 in the major salivary glands. T-stage was in 13 pts T2, in 33 T3, in 26 T4; positive nodes were in 10 pts, M+ in 15 pts. Mean tumor volume was 89 cm3. Neutron therapy was 15.03 Gy in 3 weeks with 1.67 Gy per fraction three times per week. Individual computer assisted treatment planning was performed based on CT and/or MRI, using bolus material if necessary. Target volume was the macroscopic tumor volume with a generous safety margin.Results: Complete response was achieved in 28 pts, partial response in 35 pts. Local control was observed in 73.4% after a mean observation period of 36 months. Overall and recurrence free survival was 85%/81% at two years, and 58%/53% at 5 years (Kaplan-Meier). In univariate analysis tumor volume (> 100 cm3), distant metastases, histologic subtype (solid) and neutron dose (< 15 Gy) turned out to be significant parameters for predicting outcome, in multivariate analysis tumor volume and histologic subtype remained the only significant parameters. Acute morbidity was grade III/IV (EORTC/RTOG) in 6% for skin (desquamation), in 4% for mucosa (ulceration), late morbidity (grade III/IV) in one patient with local temporal brain necrosis.Conclusion: According to this experience and taking into account the so far collected experience, fast neutron radio-therapy remains the treatment of choice for large and unresectable primary and recurrent ACC, and residual disease after surgery. [ABSTRACT FROM AUTHOR]

Background: Modern healthcare devices can be connected to computer networks and many western healthcare institutions run those devices in networks. At the same time, cyber attacks are on the rise and there is evidence that cybercriminals do not spare critical infrastructure such as major hospitals, even if they endanger patients. Intuitively, the more and closer connected healthcare devices are to public networks, the higher the risk of getting attacked.Methods: To asses the current connectivity status of healthcare devices, we surveyed the field of German hospitals and especially University Medical Center UMCs.Results: The results show a strong correlation between the networking degree and the number of medical devices. The average number of medical devices is 25.150, with a median of networked medical devices of 3.600. Actual key users of networked medical devices are the departments Radiology, Intensive Care, Radio-Oncology RO, Nuclear Medicine NUC, and Anaesthesiology in the group of UMCs. In the next five years, the usage of networked medical devices will increase significantly in the departments of Surgery, Intensive Care, and Radiology. We detected a strong correlation between the degree of connectivity and the likelihood of being attacked.The survey answers regarding the cyber security status reveal a lack of security basics in some of the inquired hospitals. We did discover successful attacks in hospitals with separated or subsidiary departments. A fusion of competencies on an organizational level facilitates the right behavior here. Most hospitals rated themselves predominantly positively in the self-assessment but also stated the usefulness of IT security insurance.Conclusions: Concluding our results, hospitals are already facing the consequences of omitted measures within their growing pool of medical devices. Continuously relying on historically grown structures without adaption and trusting manufactures to solve vectors is a critical behavior that could seriously endanger patients. [ABSTRACT FROM AUTHOR]

Purpose: Surgery is the standard treatment of soft-tissue sarcomas. Adjuvant radiotherapy with photons after less radical resection can improve local control. The rate of tumor control achieved in patients with G1 and G2 soft tissue sarcomas incompletely resected and treated postoperatively with neutron irradiation is similar to that seen in patients undergoing complete tumor resection and adjuvant photon irradiation.Patients and Methods: At the Department of Radiotherapy and Radiation Oncology of the University of Münster, 61 patients with soft tissue sarcomas were irradiated postoperatively with fast neutrons. Mainly tumors of low or intermediate malignancy (R0; 27%; R1, 21%; R2, 52%) were treated. Malignant fibrous histiocytoma, liposarcoma, and neurogenic sarcomas dominated. 46 patients were irradiated with fast neutrons alone, and 15 patients were treated with mixed beam therapy (photons and neutrons).Results: The median follow-up period was 44 months. Overall five-year survival probability analysed by Kaplan-Meyer method was 42.5%. The local control rate was 57.7%. 15 patients showed complete remission, 18 patients had a partial remission. Only 11% of the patients showed grade III and IV side effects during neutron irradiation.Conclusion: Neutron irradiation is efficocious in treating highly and intermediately differentiated soft tissue sarcomas. The result of surgical resection seems to be a very important prognostic factor for patients with soft tissue sarcomas. [ABSTRACT FROM AUTHOR]

Purpose: Comparing radiation treatment plans by using the same safety margins and dose objectives for all techniques, to ascertain the optimal radiation technique for the stereotactic body radiotherapy (SBRT) of low-risk prostate cancer.Material and Methods: Treatment plans for 27 randomly selected patients were compared using intensity-modulated (IMRT) techniques as Sliding Window (SW), volumetric modulated arc therapy (VMAT), and helical tomotherapy (HT), as well as Cyber Knife (CK) system. The target dose was calculated to 36.25 Gy delivered in five fractions over 1 week. Dosimetric indices for target volume and organs at risk (OAR) as well as normal tissue complication probability (NTCP) of late rectal and urinary bladder toxicities were analyzed.Results: The CK provided lower homogeneity in the target volume, but higher values for most of the conformity indices compared to the IMRT approaches. The SW demonstrated superior rectum sparing at medium-to-high dose range (V18 Gy - V32.6 Gy) compared to other techniques (p < 0.05). The whole urinary bladder experienced the best shielding by SW and VMAT at the medium dose (V18 Gy, p < 0.05 versus CK), however we obtained no relevant differences between techniques at the high dose. Generally, the CK demonstrated significantly superior rectum and bladder exposure at V18 Gy as compared to HT, SW, and VMAT. For the rectum, mean NTCP values were significantly superior for HT (NTCP = 2.3%, p < 0.05), and for urinary bladder, the NTCP showed no significant advantages for any technique.Conclusion: No absolute dosimetric advantage was revealed to choose between CK or IMRT techniques for the SBRT of low-grade prostate cancer. Using the same safety margins and dose objectives, IMRT techniques demonstrated superior sparing of the rectum and bladder at a medium dose compared to CK. Comparing different IMRT approaches SW displayed superior rectum sparing at a medium-to-high dose range, whereas both SW and RA revealed superior bladder sparing compared to HT. HT demonstrated a significantly lower NTCP outcome compared to CK or IMRT techniques regarding the rectum. Radiation plans can be optimized further by an individual modification of dose objectives independent of the treatment plan strategy. [ABSTRACT FROM AUTHOR]