Intensity-modulated Radiotherapy Research Articles

Long-Term Control With Proton Beam Therapy for Recurrent Prostate Cancer in the Right Perineum Following Intensity-Modulated Radiation Therapy: A Case Report

Long-Term Control With Proton Beam Therapy for Recurrent Prostate Cancer in the Right Perineum Following Intensity-Modulated Radiation Therapy: A Case Report

Impact of Radiation on Dysphagia-Related Structures: A Dosimetric and Clinical Comparative Analysis of Three-Dimensional Conformal Radiotherapy (3D-CRT) and Intensity-Modulated Radiation Therapy (IMRT) Techniques in Patients With Head and Neck Cancer

Impact of Radiation on Dysphagia-Related Structures: A Dosimetric and Clinical Comparative Analysis of Three-Dimensional Conformal Radiotherapy (3D-CRT) and Intensity-Modulated Radiation Therapy (IMRT) Techniques in Patients With Head and Neck Cancer

Developing an educational “hub”: impact of a distance-learning curriculum in a multinational cohort

PurposeTo address a gap in radiation oncology education in low- and middle-income countries (LMICs), we sought to evaluate the effectiveness and generalizability of a refined curriculum on intensity modulated radiotherapy (IMRT) offered to existing radiation therapy (RT) clinics across Africa and Latin America (LATAM) at no cost.MethodsA curriculum was created based on prior needs assessments and adapted for participating medical physicists, radiation oncologists, radiation therapists, and trainees in LMICs. English-speaking and Spanish-speaking teams of volunteer educators delivered 27 hour-long sessions 1–2 times weekly for 4 months using video conferencing to African and LATAM cohorts, respectively. Pre- and post-course multiple-choice examinations were administered to LATAM participants, and pre- and post-course self-confidence (1–5 Likert-scale) and open-ended feedback were collected from all participants.ResultsTwenty-five centers across Africa (13) and LATAM (12) participated, yielding a total of 332 enrolled participants (128 African, 204 LATAM). Sessions were delivered with a mean of 44 (22.5) and 85 (25.4) participants in the African and LATAM programs, respectively. Paired pre and post-course data demonstrated significant (p < 0.001) improvement in knowledge from 47.9 to 89.6% and self-confidence across four domains including foundations (+ 1.1), commissioning (+ 1.3), contouring (+ 1.7), and treatment planning (+ 1.0). Attendance was a significant predictor of change in self-confidence in “high attendance” participants only, suggesting a threshold effect. Qualitative data demonstrates that participants look forward to applying their knowledge in the clinical setting.ConclusionA specialized radiation oncology curriculum adapted for LMIC audiences was effective for both African and LATAM participants. Participant feedback suggests that the refined IMRT course empowered clinics with knowledge and confidence to help train others. This feasible “Hub and Spokes” approach in which a distance-learning course establishes a hub to be leveraged by spokes (learners) may be generalizable to others aiming to reduce global health care disparities through training efforts.

Postoperative radiotherapy results in 192 epithelial thymic tumours patients with 10 years of follow-up

PurposeTo assess the prognostic factors and patterns of failure of patients consecutively treated with surgery and postoperative radiation therapy (PORT) for thymic epithelial tumours (TET). Patients and methodsData from 192 TET patients who were operated and received PORT at a single centre from 1990 to 2019 was retrospectively analysed. ResultsMost patients had thymoma (77 %, B247%), were classified Masaoka-Koga stage III (35 %) or IV (32 %) and had a R0 (75 %) resection. Radiotherapy was delivered at a median dose of 50.4 Gy (range, 42–66 Gy; ≥ 60 Gy in 17 %), 63 (33 %) patients were treated by intensity-modulated radiation therapy and elective nodal radiotherapy was used for 37 %. At a median follow-up of 10.9 years, the 10-year overall survival (OS) and progression-free survival (PFS) rates were 62 % (95 % CI: 54–70 %) and 47 % (95 % CI: 39–55 %), respectively. Locoregional recurrence (LRR) occurred in 72/192 (38 %) patients, distributed as 6 local, 45 regional and 21 both local and regional. LRR were mainly located to the pleura: 66/72 (92 %) and 16/72 (22 %; 16/192 in total, 8 %) were in-field. Distant relapse (DR) were observed in 30 patients (16 %), resulting in 10-year locoregional (LRC) and distant control rates of 58 % (95 % CI: 50–66 %) and 82 % (95 % CI: 77–88 %), respectively. In the multivariate analysis, Masaoka-Koga stage (HR [hazard ratio]: 1.9; p = 0.001), thymic carcinomas/neuroendocrine tumours (TC) (HR: 1.6; p = 0.045) and ECOG PS > 1 (HR: 1.9; p = 0.02) correlated with poorer OS. Higher Masaoka-Koga stage (HR: 2.6; p < 0.001) associated with a decreased LRC but not R1 status (HR: 1.2; p = 0.5) or WHO histology classification. TC (HR: 3.4; p < 0.001) and a younger age (HR: 2.5; p = 0.02) correlated with DR. ConclusionApproximately one-third of the TET in our study experienced a LRR, mainly to the pleura, and 8% in total were in-field. The place of radiotherapy should be better defined in higher risk thymoma patients within prospective randomized studies.

Survival outcomes and toxicity profiles among patients with nonmetastatic nasopharyngeal carcinoma treated with intensity-modulated radiotherapy (IMRT) versus IMRT + carbon-ion radiotherapy: A propensity score-matched analysis.

To compare survival outcomes and toxic effects among patients with newly diagnosed nonmetastatic nasopharyngeal carcinoma (NPC) when treated with intensity-modulated radiotherapy (IMRT) versus IMRT + carbon-ion radiotherapy (CIRT). We performed a retrospective propensity score matching analysis (1:1) of patients treated with IMRT and IMRT + CIRT. Descriptive statistics were used to examine the baseline characteristics of the patients. Survival was estimated using the Kaplan-Meier method. Univariate and multivariable logistic regression analysis were used to identify the independent predictors of survival. We examined the association between risk factors and adverse events (AEs) using chi-square tests. Cox model and logistic regression were used to analyze AEs. Hundred and nine patients who received IMRT + CIRT were included and the median follow-up time was 20.6 months (range: 4.6-82 months). There were no statistically significant differences in locoregional failure-free survival, distant metastasis-free survival, disease-free survival, or overall survival between the two groups, but potentially better in IMRT + CIRT group (p > 0.05, respectively). Nodal boost was the only significant factor associated with LRFS and DFS on multivariable analysis. Thirty-seven patients (34.0%) developed grade 3 acute OMs and no grade 4 acute OMs were observed in IMRT + CIRT group. All patients in IMRT + CIRT group developed grade 1 dermatitis; while in the match group, 76 patients developed grade 1 dermatitis, 27 patients developed grade 2 dermatitis, 5 patients developed grade 3 dermatitis, 1 patient developed grade 4 dermatitis. IMRT + CIRT treatment was associated with a significant trend of lower grades of OM and dermatitis (p < 0.05, respectively). Any severe (i.e., grade 3) chronic AEs, such as xerostomia, skin fibrosis, temporal lobe necrosis, osteoradionecrosis, or radiation-induced optic neuropathy, was not observed. In this study, IMRT + CIRT was associated with significantly reduced acute toxicity burden compared with full course of IMRT, with excellent survival outcomes. Patients with persistent disease after treatment and treated with nodal boost had a worse outcome. More accurate assessments of IMRT + CIRT to primary nonmetastatic NPC patients will be imperative.

The influence of Gleason score ≤ 6 histology on the outcome of high-risk localized prostate cancer after modern radiotherapy

We aimed to retrospectively review outcomes in patients with high-risk prostate cancer and a Gleason score ≤ 6 following modern radiotherapy. We analyzed the outcomes of 1374 patients who had undergone modern radiotherapy, comprising a high-risk low grade [HRLG] group (Gleason score ≤ 6; n = 94) and a high-risk high grade [HRHG] group (Gleason score ≥ 7, n = 1125). We included 955 patients who received brachytherapy with or without external beam radio-therapy (EBRT) and 264 who received modern EBRT (intensity-modulated radiotherapy [IMRT] or stereotactic body radiotherapy [SBRT]). At a median follow-up of 60 (2–177) months, actuarial 5-year biochemical failure-free survival rates were 97.8 and 91.8% (p = 0.017), respectively. The frequency of clinical failure in the HRLG group was less than that in the HRHG group (0% vs 5.4%, p = 0.012). The HRLG group had a better 5-year distant metastasis-free survival than the HRHG group (100% vs 96.0%, p = 0.035). As the HRLG group exhibited no clinical failure and better outcomes than the HRHG group, the HRLG group might potentially be classified as a lower-risk group.

Phase II Trial of Cisplatin, Gemcitabine, and Intensity-Modulated Radiation Therapy for Locally Advanced Vulvar Squamous Cell Carcinoma: NRG Oncology/GOG Study 279.

To assess efficacy and toxicity of cisplatin (C) and gemcitabine (G) with intensity-modulated radiation therapy (IMRT) in patients with locally advanced vulvar cancer not amenable to surgery. Patients enrolled in a single-arm phase II study. Pretreatment inguinal-femoral nodal assessment was performed. Sixty-four Gy IMRT was prescribed to the vulva, with 50-64 Gy delivered to the groins/low pelvis. Radiation therapy (RT) plans were quality-reviewed pretreatment. C 40 mg/m2 and G 50 mg/m2 were administered once per week throughout IMRT. Complete pathologic response (CPR) was the primary end point. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and adverse events were assessed with Common Terminology Criteria for Adverse Events v 4.0. Fifty-seven patients enrolled, of which 52 were evaluable. The median age was 58 years (range, 25-58), and 94% were White. Forty (77%) had stage II or III disease, and all had squamous histology. A median of six chemotherapy cycles (range, 1-8) were received. Eighty-five percent of RT plans were quality-reviewed with 100% compliance to protocol. Seven patients came off trial because of toxicity or patient withdrawal. Of 52 patients available for pathologic assessment, 38 (73% [90% CI, 61 to 83]) achieved CPR. No pelvic exenterations were performed. With a median follow-up of 51 months, the 12-month PFS was 74% (90% CI, 62.2 to 82.7) and the 24-month OS was 70% (90% CI, 57 to 79). The most common grade 3 or 4 adverse events were hematologic toxicity and radiation dermatitis. There was one grade 5 event unlikely related to treatment. Weekly C and G concurrent with IMRT sufficiently improved CPR in women with locally advanced vulvar squamous cell carcinoma not amenable to surgical resection.

Does lower dose pilocarpine have a role in radiation-induced xerostomia in the modern radiotherapy era? A single-center experience based on patient-reported outcome measures.

This study aims to investigate the efficacy of lower dose pilocarpine in alleviating late dry mouth symptoms in head and neck cancer patients received radiotherapy. Eighteen head and neck cancer patients experiencing persistent dry mouth were enrolled in this study. All participants started pilocarpine treatment a median of 6months post-radiotherapy. Initially, patients received pilocarpine at 5mg/day, with a gradual increase to the recommended dose of 15mg/day. A Patient-Reported Outcome Measurement (PROMs) questionnaire assessed symptoms' severity related to hyposalivation. All patients reported symptomatic dry mouth above grade 2 before starting the medication. Pilocarpine treatment continued based on patients' self-assessment, with a median duration of 12months (range, 3-36months). The median daily maintenance dose was 10mg (range, 5 to 20mg). Total PROMs scores significantly decreased following medication, from 13 points (range 7-18 points) to 7 points (range 4-13 points) (p = 0.001). Significant improvements were observed in questions related to dry mouth (p < 0.001), water intake during eating (p = 0.01), carrying water (p = 0.01), taste (p < 0.001), and water intake during speech (p < 0.001). Initial and maintenance doses of pilocarpine were lower, and the duration of pilocarpine usage was shorter in patients treated with intensity-modulated radiation therapy compared to conformal radiotherapy (12months vs. 25months, p = 0.04). Pilocarpine may be considered at doses lower for late-term dry mouth. With modern radiotherapy techniques effectively preserving the parotid gland, short-term use may be recommended in these patients. Future studies may enhance the development of a more robust patient selection criteria model.

A Phase II Study Evaluating the Effect of Intensity-Modulated Post-Mastectomy Radiation Therapy on Implant Failure Rates in Breast Cancer Patients with Immediate, 2-Stage Implant Reconstruction, with an MRI imaging correlative substudy

BackgroundPostmastectomy radiation therapy (PMRT) is a mainstay in the adjuvant treatment of node-positive breast cancer, but it poses risks for women with breast reconstruction. Multi-beam intensity-modulated radiation therapy (IMRT) improves dose conformality and homogeneity, potentially reducing complications in breast cancer patients with implant-based reconstruction. To investigate this hypothesis, we conducted a single-arm phase II clinical trial of breast cancer patients who underwent mastectomy/axillary dissection and prosthesis-based reconstruction. MethodsThe primary endpoint was the rate of implant failure within 24 months of permanent implant placement, which would be considered an improvement over historical controls if below 16%. Implant failure (IF) was defined as removal leading to a flat chest wall or replacement with another reconstruction. Patients were analyzed in two cohorts. Cohort 1 (RT-PI) received RT to the permanent implant (PI). Cohort 2 (RT-TE) received RT to the TE. Implant failure rates, adverse events, and quality of life (QOL) were analyzed. Follow-up/post-RT assessments were compared to the baseline/pre-RT assessments at 3-10 weeks after exchange surgery. A subgroup underwent serial MRIs to explore the association of MRI-detected changes with capsular contracture, a known adverse effect of RT. ResultsBetween June 2014 and March 2017, 119 women were enrolled. Cohort 1 included 45 patients, and Cohort 2 had 74 patients. Among 100 evaluable participants, 25 experienced IF during the study period. IF occured in 8/42 (19%) and 17/58 (29%) in Cohorts 1 and 2, respectively. Among the IFs, the majority were due to capsular contracture (13), infection (7), exposure (3), and other reasons (2). Morphological shape features observed in longitudinal MRI images were associated with the development of Baker grade 3-4 contracture. ConclusionsThe rate of implant failure in reconstructed breast cancer patients treated with IMRT was similar to, but not improved over, conventional, 3D-conformal methods. MRI imaging features show promise for predicting capsular contracture but require validation in larger studies.

Assessing the adequacy of a 5-mm planning target volume margin for 4D-CT scan-based image-guided radiotherapy for locally advanced carcinoma of the lung

In developed nations, 4D-computed tomography (4D-CT)-based image-guided radiotherapy (IGRT) has become the standard for treating lung carcinoma patients, with the primary goal of achieving disease cure. However, its usage in India remains limited. Here, we compared target volume delineation for radical radiation planning in patients with locally advanced lung carcinoma using helical free-breathing CT (FBCT) and 4D-CT. In addition, we assessed the adequacy of a 5-mm planning target volume (PTV) margin with 4D-CT planning. Fifty patients with locally advanced lung cancer were enrolled in the study. Each patient underwent contouring based on 4D-CT to generate an internal target volume, and a 5-mm PTV margin (PTV_4D) was added for radical radiation. Subsequently, each patient underwent two intensity-modulated radiation therapy (IMRT) plans with comparable planning and optimization parameters. One plan was based on the FBCT-based volume (PTV_3D), while the other was based on the 4D-CT-based volume (PTV_4D). PTV, organ at risk (OAR) dose, and PTV coverage by 95% of the prescribed dose (PTVD 95_3D vs. PTVD 95_4D) were compared between the two schemes. Results revealed that 4D-CT-based planning reduced PTV (mean PTV volume: 539 cc vs. 782 cc) and lowered OAR doses (mean lung dose: 13 Gy vs. 15 Gy; mean esophagus dose: 18.5 Gy vs. 21.15 Gy; mean spinal cord max dose: 35.59 Gy vs. 37.39 Gy). At 3 months after treatment imaging, 40% of the patients showed a complete response, 48% showed a partial response, 4% showed stable disease, and 8% showed progressive disease. In conclusion, 4D-CT-based radiation planning for locally advanced lung carcinoma with a reduced PTV margin of 5 mm can dramatically decrease the PTV and OAR doses without sacrificing PTV coverage compared to FBCT-based planning. However, daily online image guidance or at least a well-defined offline image guidance protocol is recommended when employing such a small PTV margin.

Stereotactic body radiation therapy in patients with centrally located hepatocellular carcinoma: A retrospective, single-arm, multi-center study

Centrally located hepatocellular carcinoma (HCC) is difficult to be radically resected due to its special location close to major hepatic vessels. Thus, we aimed to assess whether stereotactic body radiation therapy (SBRT) can be an effective and safe approach for centrally located HCC. This retrospective study included 172 patients with centrally located HCC who were treated with SBRT. Overall survival (OS) was analyzed as the primary endpoint. Rates of progression-free survival (PFS), local control, intrahepatic relapse, extrahepatic metastasis and toxicities were analyzed as secondary endpoints. The OS rates of 1-, 3-, and 5-year were 97.7%, 86.7%, and 76.3%, respectively. The PFS/local control rates of 1-, 3-, and 5-year were 94.1%/98.2%, 76.8%/94.9%, and 59.3%/92.3%, respectively. The cumulative incidence of intrahepatic relapse/extrahepatic metastases of 1-, 3-, and 5-year were 3.7%/2.9%, 25.0%/7.4%, and 33.3%/9.8%, respectively. Both univariate and multivariate analyses revealed that patients received BED10 at 100 Gy or more had better OS. Radiation-related adverse events were mild to moderate according to Common Terminology Criteria for Adverse Events, and no toxicities over grade 3 were observed. Patients with centrally located HCC in our cohort who received SBRT had similar OS and PFS rates compared to those reported in literatures who received surgery with neoadjuvant or adjuvant intensity-modulated radiation therapy. These results indicate that SBRT is an effective and well-tolerated method for patients with centrally located HCC, suggesting that it may serve as a reasonable alternative treatment for these kind of patients.

Current perspectives on radiotherapy in hepatocellular carcinoma management: a comprehensive review.

This review examines the transformative role of external beam radiotherapy (EBRT) in managing hepatocellular carcinoma (HCC), spotlighting the progression from traditional EBRT techniques to advanced modalities like intensity-modulated radiotherapy (RT), stereotactic body RT (SBRT), and innovative particle therapy, including proton beam therapy and carbon ion RT. These advancements have significantly improved the precision and efficacy of RT, marking a paradigm shift in the multimodal management of HCC, particularly in addressing complex cases and enhancing local tumor control. The review underscores the synergistic potential of integrating RT with other treatments like transarterial chemoembolization, systemic therapies such as sorafenib, and emerging immunotherapies, illustrating enhanced survival and disease control outcomes. The efficacy of RT is addressed for challenging conditions, including advanced HCC with macrovascular invasion, and RT modalities, like SBRT, are compared against traditional treatments like radiofrequency ablation for early-stage HCC. Additionally, the review accentuates the encouraging outcomes of particle therapy in enhancing local control and survival rates, minimizing treatment-related toxicity, and advocating for continued research and clinical trials. In conclusion, the integration of RT into multimodal HCC treatment strategies, coupled with the emergence of particle therapy, is crucial for advancing oncologic management, emphasizing the need for relentless innovation and personalized treatment approaches.

Radiomics-based nomogram guides adaptive de-intensification in locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy.

This study aimed to construct a radiomics-based model for prognosis and benefit prediction of concurrent chemoradiotherapy (CCRT) versus intensity-modulated radiotherapy (IMRT) in locoregionally advanced nasopharyngeal carcinoma (LANPC) following induction chemotherapy (IC). A cohort of 718 LANPC patients treated with IC + IMRT or IC + CCRT were retrospectively enrolled and assigned to a training set (n = 503) and a validation set (n = 215). Radiomic features were extracted from pre-IC and post-IC MRI. After feature selection, a delta-radiomics signature was built with LASSO-Cox regression. A nomogram incorporating independent clinical indicators and the delta-radiomics signature was then developed and evaluated for calibration and discrimination. Risk stratification by the nomogram was evaluated with Kaplan-Meier methods. The delta-radiomics signature, which comprised 19 selected features, was independently associated with prognosis. The nomogram, composed of the delta-radiomics signature, age, T category, N category, treatment, and pre-treatment EBV DNA, showed great calibration and discrimination with an area under the receiver operator characteristic curve of 0.80 (95% CI 0.75-0.85) and 0.75 (95% CI 0.64-0.85) in the training and validation sets. Risk stratification by the nomogram, excluding the treatment factor, resulted in two groups with distinct overall survival. Significantly better outcomes were observed in the high-risk patients with IC + CCRT compared to those with IC + IMRT, while comparable outcomes between IC + IMRT and IC + CCRT were shown for low-risk patients. The radiomics-based nomogram can predict prognosis and survival benefits from concurrent chemotherapy for LANPC following IC. Low-risk patients determined by the nomogram may be potential candidates for omitting concurrent chemotherapy during IMRT. The radiomics-based nomogram was constructed for risk stratification and patient selection. It can help guide clinical decision-making for patients with locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy, and avoid unnecessary toxicity caused by overtreatment. • The benefits from concurrent chemotherapy remained controversial for locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy. • Radiomics-based nomogram achieved prognosis and benefits prediction of concurrent chemotherapy. • Low-risk patients defined by the nomogram were candidates for de-intensification.

Abstract 6300: Associations of biological aging with perceived stress in patients with head and neck cancer: A longitudinal study

Abstract Introduction: Biological aging leads to an increased risk of morbidity and mortality in patients with head and neck cancer (HNC) undergoing intensity-modulated radiotherapy (IMRT). This progression can be exacerbated by the burden of stress arising from HNC and IMRT. While stress has been linked to inflammation, the associations of biological aging measures including inflammatory markers and epigenetic age acceleration (EAA) with stress over cancer treatment remain underexplored. The purpose of this study was to examine the associations between biological aging and stress in patients with HNC receiving IMRT across four time points (i.e., pre- (T1), end of (T2), 3 months (T3), and 12 months (T4) post-IMRT). Methods: We conducted a prospective longitudinal study. Stress was assessed using the Perceived Stress Scale (PSS) across four time points along with the assessment of biological aging markers: peripheral inflammatory markers (i.e., interleukin [IL-6], IL-1β, IL-10, IL-1ra, C-reactive protein [CRP], soluble tumor necrosis factor receptor 2 [sTNFR2], and TNF-α) and EAA. EAA was calculated using DNAmPhenoAge, adjusted for chronological age. Liner mixed effects models were used to examine the associations between biological aging measures and stress across time. Results: A total of 176 patients with HNC were enrolled in the study with a mean age of 59.9±10.0 years, 72.7% male, and 77.3% non-Hispanic White. Stress scores increased from T1 to T2 (p&amp;lt;0.001), decreased significantly at T3 (p&amp;lt;0.001) which were lower than the baseline scores (T1), and then gradually decreased at T4 (p=0.029). Significant associations of CRP, IL- 1ra, and TNFR-2 with stress were identified across time (all p values &amp;lt;0.05), controlling for covariates (i.e., age, human papillomavirus status, chemotherapy, and surgery): elevated inflammatory markers were associated with higher levels of stress. In a separate model, higher stress scores were also associated with increased EAA controlling for the same covariates (p=0.015): an increment of 10 units in stress scores was associated with an age acceleration of 7.2 months across time. Conclusions: Findings from our study suggest that biological aging measures (inflammatory markers and EAA) are associated with stress across time in patients with HNC receiving IMRT. Clinicians and researchers may use the findings to develop personalized psychosocial interventions that reduce stress so as to deaccelerate biological aging for patients with HNC during their treatment and survivorship. Citation Format: Yufen Lin, Telisa Spikes, Deborah Bruner, Sudeshna Paul, Andrew Miller, Karen Conneely, Nabil Saba, Canhua Xiao. Associations of biological aging with perceived stress in patients with head and neck cancer: A longitudinal study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6300.

Long-term survival, toxicities, and the role of chrono-chemotherapy with different infusion rates in locally advanced nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy: a retrospective study with a 5-year follow-up.

This study aimed to evaluate 5-year outcomes and the late toxicity profile of chrono-chemotherapy with different infusion rates in patients with locally advanced nasopharyngeal carcinoma (NPC). Our retrospective analysis included 70 patients with locally advanced NPC stages III and IVB (according to the 2010 American Joint Committee on Cancer staging system). Patients were treated with two cycles of induction chemotherapy (IC) before concurrent chemoradiotherapy (CCRT) at Guizhou Cancer Hospital. The IC with docetaxel, cisplatin (DDP) and fluorouracil regimen. Patients were divided into two groups during CCRT. Using a "MELODIE" multi-channel programmed pump, DDP (100 mg/m2) was administered for 12 hours from 10:00 am to 10:00 pm and repeated every 3 weeks for 2-3 cycles. DDP was administered at the peak period of 4:00 pm in the sinusoidal chrono-modulated infusion group (Arm A, n=35). The patients in Arm B received a constant rate of infusion. Both arms received radiotherapy through the same technique and dose fraction. The long-term survival and disease progression were observed. After a median follow-up of 82.8 months, the 5-year progression-free survival rate was 81.3% in Arm A and 79.6% in Arm B (P = 0.85). The 5-year overall survival rate was not significantly different between Arm A and Arm B (79.6% vs 85.3%, P = 0.79). The 5-year distant metastasis-free survival rate was 83.6% in Arm A and 84.6% in Arm B (P = 0.75). The 5-year local recurrence-free survival rate was 88.2% in Arm A and 85.3% in Arm B (P = 0.16). There were no late toxicities of grade 3-4 in either group. Both groups had grade 1-2 late toxicities. Dry mouth was the most common late toxic side effect, followed by hearing loss and difficulty in swallowing. There was no statistically significant difference between Arm A and Arm B in terms of side effects. Long-term analysis confirmed that in CCRT, cisplatin administration with sinusoidal chrono-modulated infusion was not superior to the constant infusion rate in terms of long-term toxicity and prognosis.

Reirradiation of metastases of the central nervous system: part 2-metastatic epidural spinal cord compression.

An increasing number of patients irradiated for metastatic epidural spinal cord compression (MESCC) experience an in-field recurrence and require a second course of radiotherapy. Reirradiation can be performed with conventional radiotherapy or highly-conformal techniques such as intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic body radiation therapy (SBRT). When using conventional radiotherapy, a cumulative biologically effective dose (BED) ≤120 calculated with an α/β value of 2 Gy (Gy2) was not associated with radiation myelopathy in a retrospective study of 124 patients and is considered safe. In that study, conventional reirradiation led to improvements of motor deficits in 36% of patients and stopped further symptomatic progression in another 50% (overall response 86%). In four other studies, overall response rates were 82-89%. In addition to the cumulative BED or equivalent dose in 2 Gy fractions (EQD2), the interval between both radiotherapy courses <6 months and a BED per course ≥102 Gy2 (corresponding to an EQD2 ≥51 Gy2) were identified as risk factors for radiation myelopathy. Without these risk factors, a BED >120 Gy2 may be possible. Scoring tools have been developed that can assist physicians in estimating the risk of radiation myelopathy and selecting the appropriate dose-fractionation regimen of re-treatment. Reirradiation of MESCC may also be performed with highly-conformal radiotherapy. With IMRT or VMAT, rates of pain relief and improvement of neurologic symptoms of 60-93.5% and 42-73%, respectively, were achieved. One-year local control rates ranged between 55% and 88%. Rates of myelopathy or radiculopathy and vertebral compression fractures were 0% and 0-9.3%, respectively. With SBRT, rates of pain relief were 65-86%. Two studies reported improvements in neurologic symptoms of 0% and 82%, respectively. One-year local control rates were 74-83%. Rates of myelopathy or radiculopathy and vertebral compression fractures were 0-4.5% and 4.5-13.8%, respectively. For SBRT, a cumulative maximum EQD2 to thecal sac ≤70 Gy2, a maximum EQD2 of SBRT ≤25 Gy2, a ratio ≤0.5 of thecal sac maximum EQD2 of SBRT to maximum cumulative EQD2, and an interval between both courses ≥5 months were associated with a lower risk of myelopathy. Additional prospective trials are required to better define the options of reirradiation of MESCC.

Updated Analysis of Comparative Toxicity of Proton and Photon Radiation for Prostate Cancer.

Previous comparative effectiveness studies have not demonstrated a benefit of proton beam therapy (PBT) compared with intensity-modulated radiation therapy (IMRT) for prostate cancer. An updated comparison of GI and genitourinary (GU) toxicity is needed. We investigated the SEER-Medicare linked database, identifying patients with localized prostate cancer diagnosed from 2010 to 2017. Procedure and diagnosis codes indicative of treatment-related toxicity were identified. As a sensitivity analysis, we also identified toxicity based only on procedure codes. Patients who underwent IMRT and PBT were matched 2:1 on the basis of clinical and sociodemographic characteristics. We then compared GI and GU toxicity at 6, 12, and 24 months after treatment. The final sample included 772 PBT patients matched to 1,544 IMRT patients. The frequency of GI toxicity for IMRT versus PBT was 3.5% versus 2.5% at 6 months (P = .18), 9.5% versus 10.2% at 12 months (P = .18), and 20.5% versus 23.4% at 24 months (P = .11). The frequency of only procedure codes indicative of GI toxicity for IMRT versus PBT was too low to be reported and not significantly different. The frequency of GU toxicity for IMRT versus PBT was 6.8% versus 5.7% (P = .30), 14.3% versus 12.2% (P = .13), and 28.2% versus 25.8% (P = .21) at 6, 12, and 24 months, respectively. When looking only at procedure codes, the frequency of GU toxicity for IMRT was 1.0% at 6 months, whereas it was too infrequent to report for PBT (P = .64). GU toxicity for IMRT versus PBT was 3.3% versus 2.1% (P = .10), and 8.7% versus 6.7% (P = .10) at 12 and 24 months, respectively. In this observational study, there were no statistically significant differences between PBT and IMRT in terms of GI or GU toxicity.

Automatic IMRT treatment planning through fluence prediction and plan fine-tuning for nasopharyngeal carcinoma

BackgroundAt present, the implementation of intensity-modulated radiation therapy (IMRT) treatment planning for geometrically complex nasopharyngeal carcinoma (NPC) through manual trial-and-error fashion presents challenges to the improvement of planning efficiency and the obtaining of high-consistency plan quality. This paper aims to propose an automatic IMRT plan generation method through fluence prediction and further plan fine-tuning for patients with NPC and evaluates the planning efficiency and plan quality.MethodsA total of 38 patients with NPC treated with nine-beam IMRT were enrolled in this study and automatically re-planned with the proposed method. A trained deep learning model was employed to generate static field fluence maps for each patient with 3D computed tomography images and structure contours as input. Automatic IMRT treatment planning was achieved by using its generated dose with slight tightening for further plan fine-tuning. Lastly, the plan quality was compared between automatic plans and clinical plans.ResultsThe average time for automatic plan generation was less than 4 min, including fluence maps prediction with a python script and automated plan tuning with a C# script. Compared with clinical plans, automatic plans showed better conformity and homogeneity for planning target volumes (PTVs) except for the conformity of PTV-1. Meanwhile, the dosimetric metrics for most organs at risk (OARs) were ameliorated in the automatic plan, especially Dmax of the brainstem and spinal cord, and Dmean of the left and right parotid glands significantly decreased (P < 0.05).ConclusionWe have successfully implemented an automatic IMRT plan generation method for patients with NPC. This method shows high planning efficiency and comparable or superior plan quality than clinical plans. The qualitative results before and after the plan fine-tuning indicates that further optimization using dose objectives generated by predicted fluence maps is crucial to obtain high-quality automatic plans.

Pembrolizumab or placebo with chemoradiotherapy followed by pembrolizumab or placebo for newly diagnosed, high-risk, locally advanced cervical cancer (ENGOT-cx11/GOG-3047/KEYNOTE-A18): a randomised, double-blind, phase 3 clinical trial

Pembrolizumab has shown efficacy in persistent, recurrent, or metastatic cervical cancer. The effect of chemoradiotherapy might be enhanced by immunotherapy. In this phase 3 trial, we assessed the efficacy and safety of adding pembrolizumab to chemoradiotherapy in locally advanced cervical cancer. In this randomised, double-blind, placebo-controlled, phase 3 ENGOT-cx11/GOG-3047/KEYNOTE-A18 clinical trial, adults (age ≥18 years) at 176 medical centres in 30 countries with newly diagnosed, high-risk, locally advanced cervical cancer were randomly assigned (1:1) using an interactive voice-response system with integrated web response to receive 5 cycles of pembrolizumab (200 mg) or placebo every 3 weeks plus chemoradiotherapy, followed by 15 cycles of pembrolizumab (400 mg) or placebo every 6 weeks. Randomisation was stratified by planned external beam radiotherapy type (intensity-modulated radiotherapy or volumetric-modulated arc therapy vs non-intensity-modulated radiotherapy or non-volumetric-modulated arc therapy), cervical cancer stage at screening (International Federation of Gynecology and Obstetrics 2014 stage IB2-IIB node positive vs stage III-IVA), and planned total radiotherapy (external beam radiotherapy plus brachytherapy) dose (<70 Gy vs ≥70 Gy equivalent dose in 2 Gy fractions). Primary endpoints were progression-free survival per Response Evaluation Criteria in Solid Tumours version 1.1-by investigator or by histopathologic confirmation of suspected disease progression-and overall survival. Primary analysis was conducted in the intention-to-treat population, which included all randomly allocated participants. Safety was assessed in the as-treated population, which included all randomly allocated patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT04221945, and is closed to new participants. Between June 9, 2020, and Dec 15, 2022, 1060 participants were randomly assigned to treatment, with 529 assigned to the pembrolizumab-chemoradiotherapy group and 531 to the placebo-chemoradiotherapy group. At data cutoff (Jan 9, 2023), median follow-up was 17·9 months (IQR 11·3-22·3) in both treatment groups. Median progression-free survival was not reached in either group; rates at 24 months were 68% in the pembrolizumab-chemoradiotherapy group versus 57% in the placebo-chemoradiotherapy group. The hazard ratio (HR) for disease progression or death was 0·70 (95% CI 0·55-0·89, p=0·0020), meeting the protocol-specified primary objective. Overall survival at 24 months was 87% in the pembrolizumab-chemoradiotherapy group and 81% in the placebo-chemoradiotherapy group (information fraction 42·9%). The HR for death was 0·73 (0·49-1·07); these data have not crossed the boundary of statistical significance. Grade 3 or higher adverse event rates were 75% in the pembrolizumab-chemoradiotherapy group and 69% in the placebo-chemoradiotherapy group. Pembrolizumab plus chemoradiotherapy significantly improved progression-free survival in patients with newly diagnosed, high-risk, locally advanced cervical cancer. Merck Sharp & Dohme, a subsidiary of Merck & Co (MSD).

Chronic fatigue in long-term survivors of head and neck cancer treated with radiotherapy

BackgroundThere is lack of evidence on chronic fatigue (CF) following radiotherapy (RT) in survivors of head and neck cancer (HNC). We aimed to compare CF in HNC survivors > 5 years post-RT with a reference population and investigate factors associated with CF and the possible impact of CF on health-related quality of life (HRQoL). Material and methodsIn this cross-sectional study we included HNC survivors treated in 2007–2013. Participants filled in patient-reported outcome measures and attended a one-day examination. CF was measured with the Fatigue Questionnaire and compared with a matched reference population using t-tests and Cohen’s effect size. Associations between CF, clinical and RT-related factors were investigated using logistic regression. HRQoL was measured with the EORTC Quality of Life core questionnaire. ResultsThe median age of the 227 HNC survivors was 65 years and median time to follow-up was 8.5 years post-RT. CF was twice more prevalent in HNC survivors compared to a reference population. In multivariable analyses, female sex (OR 3.39, 95 % CI 1.82–6.31), comorbidity (OR 2.17, 95 % CI 1.20–3.94) and treatment with intensity-modulated RT (OR 2.13, 95 % CI 1.16–3.91) were associated with CF, while RT dose parameters were not. Survivors with CF compared to those without, had significantly worse HRQoL. ConclusionsCF in HNC survivors is particularly important for female patients, while specific factors associated with RT appear not to play a role. The high CF prevalence in long-term HNC survivors associated with impaired HRQoL is important information beneficial for clinicians and patients to improve patient follow-up.