Acute Radiation-induced Toxicity Research Articles

Prediction of Acute Radiation-Induced Lung Toxicity After Stereotactic Body Radiation Therapy Using Dose-Volume Parameters From Functional Mapping on Gallium 68 Perfusion Positron Emission Tomography/Computed Tomography

The aim of this work was to compare anatomic and functional dose-volume parameters as predictors of acute radiation-induced lung toxicity (RILT) in patients with lung tumors treated with stereotactic body radiation therapy. Fifty-nine patients treated with stereotactic body radiation therapy were prospectively included. All patients underwent gallium 68 lung perfusion positron emission tomography (PET)/computed tomography (CT) imaging before treatment. Mean lung dose (MLD) and volumes receiving x Gy (VxGy, 5-30 Gy) were calculated in 5 lung volumes: the conventional anatomic volume (AV) delineated on CT images, 3 lung functional volumes (FVs) defined on lung perfusion PET imaging (FV50%, FV70%, and FV90%; ie, the minimal volume containing 50%, 70%, and 90% of the total activity within the AV), and a low FV (LFV; LFV = AV - FV90%). The primary endpoint of this analysis was grade ≥2 acute RILT at 3 months as assessed with National Cancer Institute Common Terminology Criteria for Adverse Events version 5. Dose-volume parameters in patients with and without acute RILT were compared. Receiver operating characteristic curves assessing the ability of dose-volume parameters to discriminate between patients with and without acute RILT were generated, and area under the curve (AUC) values were calculated. Of the 59 patients, 10 (17%) had grade ≥2 acute RILT. The MLD and the VxGy in the AV and LFV were not statistically different between patients with and without acute RILT (P > .05). All functional parameters were significantly higher in acute RILT patients (P < .05). AUC values (95% CI) for MLD AV, LFV, FV50%, FV70%, and FV90% were 0.66 (0.46-0.85), 0.60 (0.39-0.80), 0.77 (0.63-0.91), 0.77 (0.64-0.91), and 0.75 (0.58-0.91), respectively. AUC values for V20Gy AV, LFV, FV50%, FV70%, and FV90% were 0.65 (0.44-0.87), 0.64 (0.46-0.83), 0.82 (0.69-0.95), 0.81 (0.67-0.96), and 0.75 (0.57-0.94), respectively. The predictive value of PET perfusion-based functional parameters outperforms the standard CT-based dose-volume parameters for the risk of grade ≥2 acute RILT. Functional parameters could be useful for guiding radiation therapy planning and reducing the risk of acute RILT.

Large-scale meta-genome-wide association study reveals common genetic factors linked to radiation-induced acute toxicities across cancer types.

This study was designed to identify common genetic susceptibility and shared genetic variants associated with acute radiation-induced toxicity across 4 cancer types (prostate, head and neck, breast, and lung). A genome-wide association study meta-analysis was performed using 19 cohorts totaling 12 042 patients. Acute standardized total average toxicity (STATacute) was modelled using a generalized linear regression model for additive effect of genetic variants, adjusted for demographic and clinical covariates (rSTATacute). Linkage disequilibrium score regression estimated shared single-nucleotide variation (SNV-formerly SNP)-based heritability of rSTATacute in all patients and for each cancer type. Shared SNV-based heritability of STATacute among all cancer types was estimated at 10% (SE = 0.02) and was higher for prostate (17%, SE = 0.07), head and neck (27%, SE = 0.09), and breast (16%, SE = 0.09) cancers. We identified 130 suggestive associated SNVs with rSTATacute (5.0 × 10‒8 < P < 1.0 × 10‒5) across 25 genomic regions. rs142667902 showed the strongest association (effect allele A; effect size ‒0.17; P = 1.7 × 10‒7), which is located near DPPA4, encoding a protein involved in pluripotency in stem cells, which are essential for repair of radiation-induced tissue injury. Gene-set enrichment analysis identified 'RNA splicing via endonucleolytic cleavage and ligation' (P = 5.1 × 10‒6, P = .079 corrected) as the top gene set associated with rSTATacute among all patients. In silico gene expression analysis showed that the genes associated with rSTATacute were statistically significantly up-regulated in skin (not sun exposed P = .004 corrected; sun exposed P = .026 corrected). There is shared SNV-based heritability for acute radiation-induced toxicity across and within individual cancer sites. Future meta-genome-wide association studies among large radiation therapy patient cohorts are worthwhile to identify the common causal variants for acute radiotoxicity across cancer types.

Évaluation de facteurs prédictifs de réponse pathologique à la radiothérapie néoadjuvante des sarcomes des tissus mous

PurposeConserving surgery combined with radiotherapy in presence of local recurrence risk factors is standard treatment of soft tissue sarcomas, a group of rare and heterogeneous tumours. Radiotherapy is performed before or after surgery. In neoadjuvant setting, late radiation-induced toxicity is reduced and pathological response to radiotherapy could be achieved. A complete pathological response to radiotherapy has recently been shown to predict better survival. Our study aims at identifying predictive factors of pathological response to neoadjuvant radiotherapy (clinical, radiological or histological) of soft tissue sarcomas. Patients and methodsClinical, imaging (MRI: perilesional oedema, necrosis, tumour heterogeneity, vasculonervous relationships) and pathological (pathological subtype, tumour grade, anticipated/obtained resection quality) data were retrospectively collected. Tumour response (imaging and pathological), patient outcome, acute and late radiation-induced toxicity, predictive factors of pathological response to neoadjuvant radiotherapy were studied. The 2-test or exact-Fisher test (qualitative variables) and by Student's t-test or Kruskal-Wallis test (quantitative variables) were used for statistical analysis. ResultsFrom April 2017 to April 2021, neoadjuvant radiotherapy (50Gy in 25 fractions) followed by surgical excision was performed to 36 consecutive patients with liposarcomas (n=17/36), or undifferentiated sarcomas (n=8/36). MRI response was complete in 1 patient, partial in 9 patients (n=9/36, 25%), stable in 21 patients (n=21/36, 58%) or in progression in 5 patients (n=5/36, 14%). Pathological response was observed in 22 patients (61%). No grade 3-4 acute radiation-induced toxicity was observed. Regarding late toxicity, 28% of patients had grade 1–2 oedema (n=10/36), 39% had a grade 1 fibrosis (n=14/36), and 30% grade 1 pain (n=11/36). No predictive factors of response to radiotherapy was statistically significant. ConclusionsNeoadjuvant radiotherapy is well-tolerated. No clinical, radiological or pathological predictive factors was identified for radiotherapy tumour response.

Comprehensive geriatric assessment predicts radiation-induced acute toxicity in prostate cancer patients.

The purpose of the present prospective study was to evaluate the significance of geriatric conditions measured by acomprehensive geriatric assessment (GA) for the prediction of the risk of high-grade acute radiation-induced toxicity. Atotal of 314 prostate cancer patients (age ≥ 65years) undergoing definitive radiotherapy at atertiary academic center were included. Prior to treatment, patients underwent aGA. High-grade toxicity was defined as acute toxicity grade ≥ 2 according to standard RTOG/EORTC criteria. To analyze the predictive value of the GA, univariable and multivariable logistic regression models were applied. A total of 40 patients (12.7%) developed acute toxicity grade ≥ 2; high grade genitourinary was found in 37patients (11.8%) and rectal toxicity in 8patients (2.5%), respectively. Multivariable analysis revealed asignificant association of comorbidities with overall toxicity grade ≥ 2 (odds ratio [OR] 2.633, 95% confidence interval [CI] 1.260-5.502; p = 0.010) as well as with high-grade genitourinary and rectal toxicity (OR 2.169, 95%CI1.017-4.625; p = 0.045 and OR 7.220, 95%CI 1.227-42.473; p = 0.029, respectively). Furthermore, the Activities of Daily Living score (OR 0.054, 95%CI 0.004-0.651; p = 0.022), social status (OR 0.159, 95%CI 0.028-0.891; p = 0.036), and polypharmacy (OR 4.618, 95%CI 1.045-20.405; p = 0.044) were identified as independent predictors of rectal toxicity grade ≥ 2. Geriatric conditions seem to be predictive of the development of high-grade radiation-induced toxicity in prostate cancer patients treated with definitive radiotherapy.

From once-weekly to semi-weekly whole prostate gland stereotactic radiotherapy with focal boosting: Primary endpoint analysis of the multicenter phase II hypo-FLAME 2.0 trial

Background and purposeThe hypo-FLAME trial showed that once-weekly (QW) focal boosted prostate stereotactic body radiotherapy (SBRT) is associated with acceptable acute genitourinary (GU) and gastrointestinal (GI) toxicity. Currently, we investigated the safety of reducing the overall treatment time (OTT) of focal boosted prostate SBRT from 29 to 15 days. Material and methodsPatients with intermediate- and high-risk prostate cancer were treated with SBRT delivering 35 Gy in 5 fractions to the whole prostate gland with an iso-toxic boost up to 50 Gy to the intraprostatic lesion(s) in a semi-weekly (BIW) schedule. The primary endpoint was radiation-induced acute toxicity (CTCAE v5.0). Changes in quality of life (QoL) were examined in terms of proportions achieving a minimal clinically important change (MCIC). Finally, acute toxicity and QoL scores of the BIW schedule were compared with the results of the prior QW hypo-FLAME schedule (n = 100). ResultsBetween August 2020 and February 2022, 124 patients were enrolled and treated BIW. No grade ≥3 GU or GI toxicity was observed. The 90-days cumulative incidence of grade 2 GU and GI toxicity rates were 47.5% and 7.4%, respectively. Patients treated QW scored significant less grade 2 GU toxicity (34.0%, p = 0.01). No significant differences in acute GI toxicity were observed. Furthermore, patients treated QW had a superior acute bowel and urinary QoL. ConclusionSemi-weekly prostate SBRT with iso-toxic focal boosting is associated with acceptable acute GU and GI toxicity. Based on the comparison between the QW and BIW schedule, patients should be counselled regarding the short-term advantages of a more protracted schedule.Registration number ClinicalTrials.gov: NCT04045717.

Radiobiological modeling of radiation-induced acute rectal mucositis: A single-institutional study of cervical carcinoma.

This study aimed to estimate the fitting parameters of sigmoidal dose-response (SDR) curve of radiation-induced acute rectal mucositis in pelvic cancer patients treated with Intensity Modulated Radiation Therapy (IMRT) for the calculation of normal tissue complication probability (NTCP). Thirty cervical cancer patients were enrolled to model the SDR curve for rectal mucositis. The patients were evaluated weekly for acute radiation-induced (ARI) rectal mucositis toxicity and their scoring was performed as per Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. The radiobiological parameters, namely n, m, TD50, and γ50 were calculated from the fitted SDR curve obtained from the clinical data of cervical cancer patients. ARI toxicity for rectal mucosa in carcinoma of cervical cancer patients was calculated for the endpoint rectal mucositis. The n, m, TD50, and γ50 parameters from the SDR curve of Grade 1 and Grade 2 rectal mucositis were found to be 0.328, 0.047, 25.44 ± 1.21 (confidence interval [CI]: 95%), and 8.36 and 0.13, 0.07, 38.06 ± 2.94 (CI: 95%), and 5.15, respectively. This study presents the fitting parameters for NTCP calculation of Grade 1 and Grade 2 ARI rectal toxicity for the endpoint of rectal mucositis. The provided nomograms of volume versus complication and dose versus complication for different grades of rectal mucositis help radiation oncologists to decide the limiting dose to reduce the acute toxicities.

Ultrasound Histogram Assessment of Acute Breast Toxicity After Breast Cancer Radiation Therapy: A Prospective Longitudinal Study.

Accurate assessment of radiation-induced breast toxicity is crucial for the management of breast radiation therapy (RT). Standard assessment of breast toxicity based on clinicians' visual inspection and palpation has considerable inter- and intra-observer variability. To overcome this challenge, we present an ultrasound histogram method that objectively evaluates radiation-induced breast toxicity longitudinally. In a prospective study, patients enrolled (n=67) received ultrasound scans at four time points: prior to RT, last day of RT, 3-4 wk post-RT and 9-12-wk post-RT. Ultrasound scans were acquired at five locations (tumor bed and 3, 6, 9 and 12 o'clock) on both breasts. Two hundred sixty-four ultrasound scans and 2640 B-mode images were analyzed. The histogram differences between irradiated and contralateral breasts were calculated to evaluate radiation-induced breast changes. On the basis of the B-mode images, the severity of breast toxicity was graded as absent, mild, moderate or severe. The performance of the histogram method was assessed with the receiver operating characteristic (ROC) curve. The areas under the ROC curve ranged from 0.78 to 0.9 (sensitivity: 0.88-0.96, specificity: 0.53-0.83) at the lower quadrant for differentiating absent/mild from moderate/severe toxicity at various time points. This study provides preliminary evidence that ultrasound histogram differences can serve as an imaging biomarker to longitudinally assess radiation-induced acute toxicity.

Ultrasound-Based Grading System for Radiation-Induced Acute Breast Toxicity.

To introduce an ultrasound-based scoring system for radiation-induced breast toxicity and test its reliability. Breast ultrasound (BUS) was performed on 32 patients receiving breast radiotherapy (RT) to assess the radiation-induced acute toxicity. For each patient, both the untreated and irradiated breasts were scanned at five locations: 12:00, 3:00, 6:00, 9:00, and tumor bed to evaluate for heterogenous responses to radiation within the entire breast. In total, 314 images were analyzed. Based on ultrasound findings such as skin thickening, dermis boundary irregularity, and subcutaneous edema, a 4-level, Likert-like grading scheme is proposed: none (G0), mild (G1), moderate (G2), and severe (G3) toxicity. Two ultrasound experts graded the severity of breast toxicity independently and reported the inter- and intra-observer reliability of the grading system. Imaging findings were compared with standard clinical toxicity assessments using Common Terminology Criteria for Adverse Events (CTCAE). The inter-observer Pearson correlation coefficient (PCC) was 0.87 (95% CI: 0.83-0.90, P < .001). For intra-observer repeatability, the PCC of the repeated scores was 0.83 (95% CI: 0.78-0.87, P < .001). Imaging findings were compared with standard clinical toxicity assessments using CTCAE scales. The PCC between BUS scores and CTCAE results was 0.62 (95% CI: 0.35-0.80, P < .001). Among all locations, 6:00 and tumor bed showed significantly greater toxicity compared with 12:00 (P=.04). BUS can investigate the cutaneous and subcutaneous tissue changes after RT. This BUS-based grading system can complement subjective clinical assessments of radiation-induced breast toxicity with cutaneous and subcutaneous sonographic information.

Radiobiological modelling of radiation-induced acute skin toxicity (dermatitis): A single institutional study of breast carcinoma.

The purpose of the study was to estimate the fitting parameters of the sigmoidal dose response (SDR) curve of radiation-induced acute dermatitis in breast cancer patients treated with intensity-modulated radiation therapy for calculation of normal tissue complication probability (NTCP). Twenty-five breast cancer patients were enrolled to model the SDR curve for acute dermatitis. The acute radiation-induced (ARI) dermatitis toxicity was assessed weekly for all the patients, and their scores were determined using the common terminology criterion adverse events version 5.0. The radiobiological parameters n, m, TD50, and γ50 were derived using the fitted SDR curve obtained from breast cancer Patient's clinical data. ARI dermatitis toxicity in carcinoma of breast patients was calculated for the end point of acute dermatitis. The n, m, TD50, and γ50 parameters from the SDR curve of Grade-1 dermatitis are found to be 0.03, 0.04, 28.65 ± 1.43 (confidence interval [CI] 95%) and 1.02 and for Grade-2 dermatitis are found to be 0.026, 0.028, 38.65 ± 1.93 (CI. 95%) and 1.01 respectively. This research presents the fitting parameters for NTCP calculation of Grade-1 and Grade-2 acute radiation-induced skin toxicity in breast cancer for the dermatitis end point. The presented nomograms of volume versus complication probability and dose versus complication probability assist radiation oncologists in establishing the limiting dose to reduce acute toxicities for different grades of acute dermatitis in breast cancer patients.

Meta-GWAS identifies the heritability of acute radiation-induced toxicities in head and neck cancer

Background and purposeWe aimed to the genetic components and susceptibility variants associated with acute radiation-induced toxicities (RITs) in patients with head and neck cancer (HNC). Materials and methodsWe performed the largest meta-GWAS of seven European cohorts (n = 4,042). Patients were scored weekly during radiotherapy for acute RITs including dysphagia, mucositis, and xerostomia. We analyzed the effect of variants on the average burden (measured as area under curve, AUC) per each RIT, and standardized total average acute toxicity (STATacute) score using a multivariate linear regression. We tested suggestive variants (p < 1.0x10-5) in discovery set (three cohorts; n = 2,640) in a replication set (four cohorts; n = 1,402). We meta-analysed all cohorts to calculate RITs specific SNP-based heritability, and effect of polygenic risk scores (PRSs), and genetic correlations among RITS. ResultsFrom 393 suggestive SNPs identified in discovery set; 37 were nominally significant (preplication < 0.05) in replication set, but none reached genome-wide significance (pcombined < 5 × 10-8). In-silico functional analyses identified “3′-5'-exoribonuclease activity” (FDR = 1.6e-10) for dysphagia, “inositol phosphate-mediated signalling” for mucositis (FDR = 2.20e-09), and “drug catabolic process” for STATacute (FDR = 3.57e-12) as the most enriched pathways by the RIT specific suggestive genes. The SNP-based heritability (±standard error) was 29 ± 0.08 % for dysphagia, 9 ± 0.12 % (mucositis) and 27 ± 0.09 % (STATacute). Positive genetic correlation was rg = 0.65 (p = 0.048) between dysphagia and STATacute. PRSs explained limited variation of dysphagia (3 %), mucositis (2.5 %), and STATacute (0.4 %). ConclusionIn HNC patients, acute RITs are modestly heritable, sharing 10 % genetic susceptibility, when PRS explains < 3 % of their variance. We identified numerus suggestive SNPs, which remain to be replicated in larger studies.

Adaptive Individualized high-dose preoperAtive (AIDA) chemoradiation in high-risk rectal cancer: a phase II trial

PurposeTo evaluate the pathological complete response (pCR) rate of locally advanced rectal cancer (LARC) after adaptive high-dose neoadjuvant chemoradiation (CRT) based on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG-PET/CT).MethodsThe primary endpoint was the pCR rate. Secondary endpoints were the predictive value of 18 F-FDG-PET/CT on pathological response and acute and late toxicity. All patients performed 18 F-FDG-PET/CT at baseline (PET0) and after 2 weeks during CRT (PET1). The metabolic PET parameters were calculated both at the PET0 and PET1. The total CRT dose was 45 Gy to the pelvic lymph nodes and 50 Gy to the primary tumor, corresponding mesorectum, and to metastatic lymph nodes. Furthermore, a sequential boost was delivered to a biological target volume defined by PET1 with an additional dose of 5 Gy in 2 fractions. Capecitabine (825 mg/m2 twice daily orally) was prescribed for the entire treatment duration.ResultsEighteen patients (13 males, 5 females; median age 55 years [range, 41–77 years]) were enrolled in the trial. Patients underwent surgical resection at 8–9 weeks after the end of neoadjuvant CRT. No patient showed grade > 1 acute radiation-induced toxicity. Seven patients (38.8%) had TRG = 0 (complete regression), 5 (27.0%) showed TRG = 2, and 6 (33.0%) had TRG = 3. Based on the TRG results, patients were classified in two groups: TRG = 0 (pCR) and TRG = 1, 2, 3 (non pCR). Accepting p < 0.05 as the level of significance, at the Kruskal–Wallis test, the medians of baseline-MTV, interim-SUVmax, interim-SUVmean, interim-MTV, interim-TLG, and the MTV reduction were significantly different between the two groups. 18 F-FDG-PET/CT was able to predict the pCR in 77.8% of cases through compared evaluation of both baseline PET/CT and interim PET/CT.ConclusionsOur results showed that a dose escalation on a reduced target in the final phase of CRT is well tolerated and able to provide a high pCR rate.

Hypofractionated versus conventional intensity-modulated radiation irradiation (HARVEST-adjuvant): study protocol for a randomised non-inferior multicentre phase III trial

IntroductionShort course regimen has become the major trend in the field of adjuvant radiotherapy for patients with breast cancer. Hypofractionated radiotherapy (HF-RT) regimen of 40–42.5 Gy in 15–16 fractions has...

The effect of delayed primary treatment initiation on adverse events and recurrence in older head and neck cancer patients

Background and purposeAs a result of rapid tumor growth in head and neck squamous cell carcinoma (HNSCC), delay in treatment initiation can result in tumor progression and inferior outcome. Especially older and frail patients are prone to develop adverse events. The aim of this study was to assess the effect of delay on development of adverse events and recurrence in older HNSCC patients. Materials and methodsThis cohort study with prospectively collected data included all newly diagnosed, curatively treated HNSCC patients (≥60 years) between 2015 and 2017. Time-to-treatment interval and geriatric domains were assessed. Adverse events were defined as postoperative complications (Clavien-Dindo classification) and acute radiation-induced toxicity (Common Terminology Criteria of Adverse Events). Multivariable regression models were performed, using adverse events and recurrence as outcome variables. ResultsA total of 245 patients were included. Median time-to-treatment was 26 days for surgery patients and 40 days for radiotherapy patients (p < 0.001). Delayed treatment initiation was not associated with postoperative complications or acute radiation-induced toxicity.Delay was significantly associated with recurrence risk within two years after treatment initiation in a model adjusted for stage and tumor location in patients treated with initial surgery (HR:4.1, 95%CI:1.2–14.0, p = 0.024). For patients treated with radiotherapy, delay was not significantly associated with recurrence risk. ConclusionDelayed treatment initiation was independently associated with increased recurrence risk in patients treated with initial surgery. Delay was not associated with short-term adverse events. These findings highlight the importance of establishing fast-track care pathways to minimize delays and improve especially long-term outcome.

The association of frailty and outcomes of geriatric assessment with acute radiation-induced toxicity in patients with head and neck cancer

Background and purposeGeriatric impairments and frailty are highly prevalent in patients with head and neck cancer (HNC). This study investigated the association of frailty and outcomes of geriatric assessment (GA) with radiation-induced toxicity (RIT) in patients undergoing (chemo)radiotherapy ((C)RT) for HNC. Materials and methodsBetween October 2014 and April 2016, patients with HNC were prospectively included in OncoLifeS, an institutional data-biobank. Before treatment initiation, patients underwent GA and frailty screening (Groningen Frailty Indicator and Geriatric 8). The main outcome of this study was RIT (weight loss, mucositis, salivary gland inflammation, oral pain, sore throat, hoarseness, dry mouth, dysgeusia, dysphagia and general pain) according to the common terminology criteria of adverse events (CTCAE) version 4.0. Linear mixed models were performed, to analyse factors associated with increasing mean RIT over time during the treatment period. Results160 patients were included. 114 (71.3%) were male and the mean age was 66.1 years. Age ≥ 65 (β = 0.03(95 %CI = 0.01;0.05), p = 0.01), regional RT (β = 0.05(95 %CI = 0.02;0.09), p = 0.004), and concurrent chemotherapy (β = 0.04(95 %CI = 0.02;0.07), p = 0.001), were independent factors associated with increasing toxicity during the 7-week treatment period, adjusted for relevant covariates. None of the single items of GA, as well as the frailty screening instruments, were associated with increasing RIT. ConclusionIn this study, frailty and GA were not associated with additional RIT during treatment. These results suggest that (C)RT is equally tolerated in frail and non-frail patients, with respect to acute RIT. RT could be a suitable alternative to surgery in selected frail patients.

Radiobiological modeling of radiation-induced acute proctitis: A single-institutional study of prostate carcinoma.

To estimate the fitting parameters of the sigmoidal dose response (SDR) curve of radiation-induced acute proctitis in prostate cancer patients treated with intensity modulated radiation therapy (IMRT) for the calculation of normal tissue complication probability (NTCP). Twenty-five prostate cancer patients were enrolled and evaluated weekly for acute radiation-induced (ARI) proctitis toxicity. Their scoring was performed as per common terminology criteria for adverse events version 5.0. The radiobiological parameters namely n, m, TD50, and γ50 were calculated from the fitted SDR curve obtained from the clinical data of prostate cancer patients. ARI toxicity for rectum in carcinoma of prostate patients was calculated for the endpoint of acute proctitis. The n, m, TD50, and γ50 parameters from the SDR curve of Grade 1 and Grade 2 acute proctitis are found to be 0.13, 0.10, 30.48 ± 1.52 (confidence interval [CI] 95%), 3.18 and 0.08, 0.10, 44.37 ± 2.21 (CI 95%), 4.76 respectively. This study presents the fitting parameters for NTCP calculation of Grade-1 and Grade-2 ARI rectum toxicity for the endpoint of acute proctitis. The provided nomograms of volume versus complication and dose versus complication for different grades of acute proctitis in the rectum help radiation oncologists to decide the limiting dose to reduce the acute toxicities.

Impact of sarcopenia on acute radiation-induced toxicity in head and neck cancer patients

Background and purposeSarcopenia is related to late radiation-induced toxicities and worse survival in head and neck cancer (HNC) patients. This study tested the hypothesis that sarcopenia improves the performance of current normal tissue complication probability (NTCP) models of radiation-induced acute toxicity in HNC patients. Material/methodsThis was a retrospective analysis in a prospective cohort of HNC patients treated from January 2007 to December 2018 with (chemo)radiotherapy. Planning CT scans were used for evaluating skeletal muscle mass. Characteristics of sarcopenic and non-sarcopenic patients were compared. The impact of sarcopenia was analysed by adding sarcopenia to the linear predictors of current NTCP models predicting physician- and patient-rated acute toxicities. ResultsThe cut-off values of sarcopenia in the study population (n = 977) were established at skeletal muscle index < 42.0 cm2/m2 (men) and < 31.2 cm2/m2 (women), corresponding to the lowest sex-specific quartile. Compared to non-sarcopenic patients, sarcopenic patients were more frequently smokers (61% vs. 48%, p < 0.001), had more often advanced stage of disease (stage III-IV, p = 0.004), higher age (67 vs. 63 years, p < 0.001) and experienced more pretreatment complaints, such as dysphagia (grade ≥ 2, p < 0.001). Sarcopenia remained statistically significant, next to the linear predictor, only for physician-rated grade ≥ 3 dysphagia (week 3–6 during RT, p < 0.01). However, sarcopenia did not improve the performance of these NTCP models (p > 0.99). ConclusionSarcopenia in HNC patients was an independent prognostic factor for radiation-induced physician-rated acute grade ≥ 3 dysphagia, which might be explained by its impact on swallowing muscles. However, addition of sarcopenia did not improve the NTCP model performance.

A two-stage genome-wide association study of radiation-induced acute toxicity in head and neck cancer

BackgroundMost head and neck cancer (HNC) patients receive radiotherapy (RT) and develop toxicities. This genome-wide association study (GWAS) was designed to identify single nucleotide polymorphisms (SNPs) associated with common acute radiation-induced toxicities (RITs) in an HNC cohort.MethodsA two-stage GWAS was performed in 1279 HNC patients treated with RT and prospectively scored for mucositis, xerostomia, sticky saliva, and dysphagia. The area under the curve (AUC) was used to estimate the average load of toxicity during RT. At the discovery study, multivariate linear regression was used in 957 patients, and the top-ranking SNPs were tested in 322 independent replication cohort. Next, the discovery and the replication studies were meta-analyzed.ResultsA region on 5q21.3 containing 16 SNPs showed genome-wide (GW) significance association at P-value < 5.0 × 10–8 with patient-rated acute xerostomia in the discovery study. The top signal was rs35542 with an adjusted effect size of 0.17*A (95% CI 0.12 to 0.23; P-value < = 3.78 × 10–9). The genome wide significant SNPs were located within three genes (EFNA5, FBXL17, and FER). In-silico functional analysis showed these genes may be involved in DNA damage response and co-expressed in minor salivary glands. We found 428 suggestive SNPs (P-value < 1.0 × 10–5) for other toxicities, taken to the replication study. Eleven of them showed a nominal association (P-value < 0.05).ConclusionsThis GWAS suggested novel SNPs for patient-rated acute xerostomia in HNC patients. If validated, these SNPs and their related functional pathways could lead to a predictive assay to identify sensitive patients to radiation, which may eventually allow a more individualized RT treatment.

Investigating the Role of Inflammasome Caspases 1 and 11 in the Acute Radiation Syndrome.

Exposure to high dose radiation causes life-threatening acute and delayed effects. Defining the mechanisms of lethal radiation-induced acute toxicity of gastrointestinal and hematopoietic tissues are critical steps to identify drug targets to mitigate and protect against the acute radiation syndrome (ARS). For example, one rational approach would be to design pharmaceuticals that block cell death pathways to preserve tissue integrity in radiation-sensitive organ systems including the gastrointestinal tract and hematopoietic compartment. A previous study reported that the inflammasome pathway, which mediates inflammatory cell death through pyroptosis, promotes ARS. However, we show that mice lacking the inflammatory executioner caspases, caspase-1 and caspase-11, are not protected from ARS when compared directly to littermates expressing caspase-1 and caspase-11. These results suggest that alternative pathways will need to be targeted by drugs that successfully mitigate and protect against the ARS.

Treatment optimization of pelvic external beam radiation and/or vaginal brachytherapy for patients with stage I to II high-risk Endometrioid adenocarcinoma: a retrospective multi-institutional analysis

BackgroundFor stage I to II high-risk endometrioid adenocarcinoma patients, the optimal adjuvant radiotherapy modality remains controversial. The present study sought to optimize the treatment of pelvic external beam radiation (EBRT) with/or vaginal brachytherapy (VBT) for high-risk endometrioid adenocarcinoma patients in multiple radiation oncology centers across China.MethodsThis article retrospectively reviewed stage I to II patients with resected endometrioid adenocarcinoma treated at 13 radiation centers from 1999 to 2015. Patients were eligible if they had high-risk features (stage IB Grade 3 disease or stage II Grade 1–3 disease) on the basis of ESMO-ESGO-ESTRO risk group consensus.ResultsA total of 218 patients were included. Fifty-one patients received EBRT, 25 patients received VBT, and 142 patients were administered EBRT combined with VBT. The three groups were comparable in baseline characteristics, except the proportion of stage IB and Grade 3 disease in the VBT group was significantly higher and their age was older. Survival analysis showed that OS, DFS, LRFS and DMFS were significantly different among the three groups. Two out of three groups were compared with each other, and results demonstrated that DFS, LRFS and DMFS were worse in the VBT group than in the EBRT or EBRT + VBT group. The 3-year OS rates were 95.2, 85.2 and 95.1% in the EBRT, VBT and EBRT + VBT groups, respectively (p = 0.043). There was no significant difference in survival outcomes between EBRT group and EBRT + VBT group. A propensity matching analysis was performed to eliminate group differences. The results demonstrated that DFS and LRFS were significantly improved in the pelvic radiation group compared to the VBT group. Distant failure accounted for most of the failure patterns. Patients in the VBT group had significantly increased local and regional recurrence rates than patients in the EBRT or EBRT + VBT group. Acute and chronic radiation-induced toxicities were well tolerated for all patients.ConclusionFor patients with postoperative stage I to II high-risk endometrioid adenocarcinoma, compared with VBT alone, radiotherapy modalities including EBRT significantly improved DFS, LRFS and DMFS with tolerable adverse effects. Overall survival was not significantly different between EBRT and EBRT + VBT modalities.

Frailty and restrictions in geriatric domains are associated with surgical complications but not with radiation-induced acute toxicity in head and neck cancer patients: A prospective study

ObjectivesWe aimed to evaluate the association between frailty screening and geriatric assessment (GA) on short term adverse events in patients treated for head and neck cancer (HNC) for the first time in a prospective study. Materials and methodsNewly diagnosed HNC patients undergoing curative treatment were prospectively included in OncoLifeS, a data biobank. Prior to the start of treatment, frailty was assessed with a GA, Groningen Frailty Indicator (GFI) and Geriatric-8 (G8). The GA included comorbidity (Adult Comorbidity Evaluation – 27), nutritional status (Malnutrition Universal Screening Tool), functional status ((instrumental) Activities of Daily Living), mobility (Timed Up & Go), psychological (Geriatric Depression Scale 15) and cognitive (Mini Mental State Examination) measures. Clinically relevant postoperative complications (Clavien-Dindo ≥ grade 2) and acute radiation-induced toxicity (Common Terminology Criteria for Adverse Events version 4.0 ≥ grade 2) were defined as outcome measures. Univariable and multivariable logistic regression analyses were performed, yielding odds ratios (ORs) and 95% confidence intervals (95%CIs). ResultsOf the 369 included patients, 259 patients were eligible for analysis. Postoperative complications occurred in 41/148 (27.7%) patients and acute radiation-induced toxicity was present in 86/160 (53.7%) patients. Number of deficit domains of GA (OR = 1.71, 95%CI = 1.14–2.56), GFI (OR = 2.54, 95%CI = 1.02–6.31) and G8 (OR5.59, 95%CI = 2.14–14.60) were associated with postoperative complications, but not with radiation-induced toxicity. ConclusionFrailty and restrictions in geriatric domains were associated with postoperative complications, but not with radiation-induced acute toxicity in curatively treated HNC patients. The results of this prospective study further emphasizes the importance of geriatric evaluation, particularly before surgery.