Purpose Radiotherapy is integral in the management of hematological malignancies (HM). Standard radiotherapy dose fractionation regimens range between 20-50 Gy in 10-25 fractions over 2-5 weeks. This study presents the outcomes of patients with HM treated with hypofractionation radiotherapy (HFRT) during the COVID-19 pandemic. Methods Patients (N=36) were treated with HFRT between January 2020 and September 2022. The outcomes measured were the overall response rate (ORR), freedom from local progression (FFLP), and overall survival (OS). Results Median follow-up was 13.2 months. Thirty-three patients (92%) had non-Hodgkin (NHL) or Hodgkin lymphoma (HL). Eighteen patients (50%) had aggressive and 9 (25%) had indolent NHL. Nineteen patients (53%) presented with stage I/II and 15(42%) with stage III/IV disease. Twenty-five (69.4%) and eleven (30%) received consolidative and definitive RT, respectively. Twenty patients (56%) received treatment to the neck and/or thorax, and 9 (25%) to the abdomen or pelvis. Total dose ranged from 18 to 42.5 Gy in 6-17 fractions/ 2.67-5 Gy per fraction. Median dose in 2 Gy fractions for an alpha/beta (α/β) ratio of 10 amounted to 39 Gy (SD ± 13.86), and 43.6 Gy (SD ± 12) for an α/β of 3. The most commonly used fractionation scheme was 39 Gy in 13 fractions. ORR was 94.4% for the entire cohort, and 100, 94.4, and 83.3% for indolent NHL, aggressive NHL, and HL patients. Two-year FFLP was 76% (95% CI: 34-93%) for the entire cohort, and 100, 87 (95%CI: 56.4-96.5%) and 42% (95% CI: 1.1-84.3%) for the indolent NHL, aggressive NHL, and HL patients. Two-year OS for the entire cohort was 80% (95% CI:59.9-90.5%), and 100, 66.1 (95% CI: 36.4-84.4%) and 100% for the indolent NHL, aggressive NHL, and HL patients. Only one patient presented with grade two pulmonary toxicity. Conclusion HFRT in HM provides excellent local control without any increase in toxicity.

Stereotactic body radiation therapy (SBRT) is a precise and conformal radiation therapy (RT) that aims to deliver a high dose of radiation to the tumor with sparing surrounding normal tissue, making it an attractive option for head and neck cancer (HNC) patients who are not suitable for traditional long course of RT with comprehensive RT target volume. Definitive SBRT for HNC has been investigated in different settings, including early stage glottis cancer, and as alternative to brachytherapy boost after external beam RT. It also used as a primary treatment option for elderly or medically unfit patients. More recently, SBRT combination with immunotherapy in the neoadjuvant setting for HNC showed promising results. Salvage or adjuvant SBRT for HNC can be used in appropriately selected cases. Future studies are warranted to determine the optimum dose and fractionation schedules in any of these indications.

Background: Optimal hypofractionated schedule of post-prostatectomy radiotherapy remains to be established. We evaluated treatment outcomes and toxicity of the moderately hypofractionated post-prostatectomy radiotherapy in 16 daily fractions delivered with IMRT/VMAT. The treatment schedule selection was motivated by limited technology resources. Methods: One hundred consecutive M0 patients with post-prostatectomy radiotherapy were evaluated. Radiotherapy indication was adjuvant (ART) in 19%, early salvage (eSRT) in 46% and salvage (SRT) in 35%. The dose prescription for prostate bed PTV was 52.8 Gy in 16 fractions of 3.3 Gy. The Common Terminology Criteria v.4 for Adverse Events scale was used for toxicity grading. Results: The median follow-up was 61 months. Five-year biochemical recurrence-free survival (bRFS) was 78.6%, distant metastases-free survival was 95.7% and overall survival was 98.8%. Treatment indication was the only significant factor for 5-year bRFS in multivariate analysis which was 84.6% vs. 67.6% for ART or eSRT vs. SRT respectively (HR 0.15, 95% CI 0.05–0.47, p=0.001). Acute GI toxicity grade 2 was recorded in 24%, grade 3 in 2% and acute GU toxicity grade 2 in 10% and no grade 3. Cumulative rate of late GI toxicity grade ≥2 was observed in 9% and late GU toxicity grade ≥2 in 16%. Conclusion: Observed results confirmed efficacy and acceptable toxicity of post-prostatectomy hypofractionated radiotherapy in 16 daily fractions.

Abstract: Background: Intensity modulated radiotherapy (IMRT) is still a standard of care for radiotherapy in locally advanced head and neck cancer (LA-HNSCC). Simultaneous integrated boost (SIB) and moderate hypofractionation offer an opportunity for individual dose painting and a reduction in overall treatment time. We present retrospective data on toxicity and locore-gional control of a patient cohort with LA-HNSCC treated with an IMRT-SIB concept in compar-ison to normofractionated 3D-conformal radiotherapy (3D-RT) after a long-term follow-up. Methods: Between 2012 and 2014, n=67 patients with HNSCC (stages III/IV without distant me-tastases) were treated with IMRT-SIB either definitively (single/total doses: 2.2/66 Gy, 2.08/62.4 Gy, 1.8/54 Gy in 30 fractions) or in the postoperative setting (2.08/62.4 Gy, 1.92/57.6 Gy, 1.8/54 Gy). These patients' clinical courses were matched (for sex, primary, and treatment concept) as part of a matched-pair analysis with patients treated before mid-2012 with normofractionated 3D-CRT (definitive: 2/50 Gy followed by a sequential boost up to 70 Gy; postoperative: 2/60-64 Gy). Chemotherapy/ immunotherapy was given concomitantly in both groups in the definitive situation (postoperative dependent on risk factors). The primary endpoints were acute and late toxicity; the secondary endpoint was locoregional control (LRC). Results: Sixty-seven patients treated with IMRT-SIB (n = 20 definitive, n = 47 adjuvant) were matched with 67 patients treated with 3D-RT. There were minor imbalances between the groups concerning nonmatching variables such as extracapsular extension (ECE) and chemotherapy in IMRT-SIB. Significantly less toxicity was found in favor of IMRT-SIB concerning dysphagia, ra-diation dermatitis, xerostomia, fibrosis, and lymphedema. After a median follow-up of 63 months, the median LRC was not reached (IMRT-SIB) vs. 69.5 months (3D-RT) (p=0.63). Conclusions: This moderately hypofractionated IMRT-SIB concept was shown to be feasible with less toxicity than conventional 3D-RT in this long-term follow-up observation.