Tattoo-Free Setup for Patients With Breast Cancer Receiving Regional Nodal Irradiation

PURPOSE

Patients undergoing regional nodal irradiation (RNI) with either 3-dimensional conformal radiation therapy (3DCRT) planning or volumetric modulated arc therapy (VMAT) receive permanent tattoos to assist with daily setup alignment and verification. With the advent of surface imaging, tattoos may not be necessary to ensure setup accuracy. We compared the accuracy of conventional tattoo-based setups to those without reference to tattoos.

METHODS AND MATERIALS

Forty-eight patients receiving RNI at our institution from July 2019 to December 2020 were identified. All patients received tattoos per standard of care. Twenty-four patients underwent setup using tattoos for initial positioning followed by surface and x-ray imaging. A subsequent 24 patients underwent positioning using surface imaging followed by x-ray imaging without reference to tattoos. Patient cohorts were balanced by treatment technique and use of deep inspiration breath hold. Treatment (including setup and delivery) time and x-ray-based shifts after surface imaging were recorded.

RESULTS

Among patients in the tattoo group receiving 3DCRT RNI, the average treatment time per fraction was 21.35 versus 19.75 minutes in the 3DCRT RNI no-tattoo cohort (P = .03). Mean 3D vector shifts for patients in the tattoo cohort were 5.6 versus 4.4 mm in the no-tattoo cohort. The average treatment time per fraction for the tattoo VMAT RNI cohort was 23.16 versus 20.82 minutes in the no-tattoo VMAT RNI cohort (P = .08). Mean 3D vector shifts for the patients in the tattoo VMAT cohort were 5.5 versus 7.1 mm in the no-tattoo VMAT cohort. Breath hold technique and body mass index did not affect accuracy in a consistent or clinically relevant way.

CONCLUSIONS

Using a combination of surface and x-ray imaging, without reference to tattoos, provides excellent accuracy in alignment and setup verification among patients receiving RNI for breast cancer, regardless of treatment technique and with reduced treatment time. Skin-based tattoos are no longer warranted for patients receiving supine RNI.

Escalation of radiotherapy dose in large locally advanced drug-resistant gastrointestinal stromal tumors by multi-shell simultaneous integrated boost intensity-modulated technique: a feasibility study

BACKGROUND

Resistance to conventional dose schemes and radiotoxicity of healthy tissue is a clinical challenge in the radiation therapy of large locally advanced drug-resistant gastrointestinal stromal tumor (LADR-GIST). This study aimed to assess the feasibility of using multi-shell Simultaneous Integrated Boost Intensity-Modulated modality (SIB-IMRT) strategy to provide a safe and effective escalation dose regimen for LADR-GIST.

METHODS

7 patients with LADR-GIST were selected in this study. The modified SIB-IMRT plans for all patients were generated by delivering different escalation-dose gradients to four ring shaped regions (shells) within the gross tumor volume (GTV). The doses of the central volume of the tumor (GTVcenter) were escalated up to 70-92.5 Gy (25 fractions), while the doses of planning target volume (PTV) and shell-1 were kept at 50.0 Gy. Based on different escalation-dose gradients, the modified SIB-IMRT plans were divided into four groups (SIB-IMRT groups). For comparison purposes, plans obtained by conventional IMRT technique (Con-IMRT) with 50 Gy (25 fractions) were also generated for all patients (Con-IMRT group). All plans were normalized to cover 95% of the PTV with the prescribed dose of 50.0 Gy. The equivalent uniform dose (EUD), relative equivalent uniform dose (rEUD), dose volume histogram (DVH), dose profile, conformity index (CI) and monitor unit (MU) were evaluated in five groups. The Friedman Test was performed to determine whether there were significant differences (P < 0.05).

RESULTS

Compared with the Con-IMRT group, the EUD of GTV (EUDGTV) and rEUD of SIB-IMRT groups were improved when escalation-dose gradient was increased, and the improvement became significant when the escalation-dose gradient reached 20% of the prescription dose. The rEUD tended to be stable as the escalation-dose gradient went up to 25% of the prescription dose. There were no significant differences in CIs and DVH metrics for OARs between the Con-IMRT group and any SIB-IMRT group, but the significant differences were observed between the SIB10-IMRT group and the SIB25-IMRT group. For the SIB-IMRT groups, as the dose gradient became steeper in the dose profiles, the higher dose was mainly accumulated in the inner part of GTV accompanied with a higher MU.

CONCLUSIONS

The proposed multi-shell SIB-IMRT strategy is feasible in dosimetry for LADR-GIST and can acquire higher therapeutic gain without sacrifice of healthy tissues. It appears that the scheme of delivering 20% of the prescribed escalation-dose gradient to the target volume can provide satisfactory dose irradiation for LADR-GIST, and it should be evaluated in future clinical study.

Incidental nodal irradiation in patients with esophageal cancer undergoing (chemo)radiation with 3D-CRT or VMAT

The extent of elective nodal irradiation (ENI) in patients undergoing definitive chemoradiotherapy (dCRT) for esophageal squamous cell carcinoma (ESCC) remains unclear. The aim of this dosimetric study was to evaluate the extent of incidental nodal irradiation using modern radiation techniques. A planning target volume (PTV) was generated for 30 patients with node-negative esophageal carcinoma (13 cervical/upper third, 7 middle third, 10 lower third/abdomen). Thereby, no elective nodal irradiation (ENI) was intended. Both three-dimensional conformal radiotherapy (3D-CRT) and volumetric-modulated arc therapy (VMAT) treatment plans (50 Gy in 25 fractions) were calculated for all patients. Fifteen nodal stations were contoured according to the definitions of the AJCC and investigated in regard to dosimetric parameters. Compared to 3D-CRT, VMAT was associated with lower dose distribution to the organs at risk (lower Dmean, V20 and V30 for the lungs and lower Dmean and V30 for the heart). For both techniques, the median Dmean surpassed 40 Gy in 12 of 15 (80%) nodal stations. However, VMAT resulted in significantly lower Dmeans and equivalent uniform doses (EUD) compared to 3D-CRT for eight nodal stations (1L, 2L, 2R, 4L, 7, 8L, 10L, 15), while differences did not reach significance for seven nodal station (1R, 4R, 8U, 8M, 10R, 16). For dCRT of ESCC, the use of VMAT was associated with significantly lower median (incidental) doses to eight of 15 regional lymph node areas compared to 3D-CRT. However, given the small absolute differences, these differences probably do not impair (regional) tumor control rates.

Comment on Ivanov et al. Ultra-Hypofractionated vs. Moderate Fractionated Whole Breast Three Dimensional Conformal Radiotherapy during the COVID-19 Pandemic. Medicina 2022, 58, 745

I read the paper by Ivanov et al. [...].

Association of volumetric-modulated arc therapy with radiation pneumonitis in thoracic esophageal cancer

The lung volume receiving low-dose irradiation has been reported to increase in volumetric-modulated arc radiotherapy (VMAT) compared with three-dimensional conformal radiotherapy (3DCRT) for thoracic esophageal cancer, which raises concerns regarding radiation pneumonitis (RP) risk. This single institutional retrospective cohort study aimed to explore whether VMAT for thoracic esophageal cancer was associated with RP. Our study included 161 patients with thoracic esophageal cancer, of whom 142 were definitively treated with 3DCRT and 39 were treated with VMAT between 2008 and 2018. Radiotherapy details, dose-volume metrics, reported RP risk factors and RP incidence were collected. The RP risk factors were assessed via multivariate analysis. Dose-volume analysis showed that VMAT delivered more conformal dose distributions to the target volume (P < 0.001) and reduced V30 Gy of heart (57% vs 41%, P < 0.001) but increased V5 Gy (54% vs 41%, P < 0.001) and V20 Gy (20% vs 17%, P = 0.01) of lungs compared with 3DCRT. However, the 1-year incidence rates of RP did not differ between the two techniques (11.3% in 3DCRT vs 7.7% in VMAT, P = 0.53). The multivariate analysis suggested that the presence of interstitial lung disease (ILD) (P = 0.01) and V20 Gy of lungs ≥20% (P = 0.008) were associated with RP. Conclusively, VMAT increased the lung volume receiving low to middle doses irradiation, although this might not be associated with RP. Further studies are needed to investigate the effect of using VMAT for delivering conformal dose distributions on RP.

Ultra-Hypofractionated vs. Moderate Fractionated Whole Breast Three Dimensional Conformal Radiotherapy during the COVID-19 Pandemic

Background and Objectives: Reducing time of treatment during COVID-19 outbreaks has been recommended by the leading Radiation Oncology societies. Still minimizing radiation induced tissue toxicity is one of the most important issues in breast cancer patients. The study aimed to investigate compliance, clinical and dosimetry normal tissue toxicity, and cosmetic results between moderated and ultra-fractionated regimes for breast cancer patients during COVID-19 pandemic. Materials and Methods: This pilot prospective randomized study included 60 patients with early breast cancer after preserving surgery, 27 patients advocated to ultra-hypofractionated whole-breast three dimensional (3D) conformal radiotherapy of 26 Gy in 5 fractions over 1 week and 33 patients with moderate fractionated breast 3D conformal radiotherapy patients between March 2020 and July 2020, during the COVID pandemic outbreak. The compliance to treatment, dosimetric parameters, acute and late skin toxicity, subcutaneous tissue toxicity, cosmetic results and clinical follow up for 18 months for the two regimes were analyzed and compared. Results: When two regimes were compared 5 fraction group had significantly lower prevalence of newly infected cases of SARS-CoV-2 and thus delayed/interrupted treatment (p = 0.05), comparable grade 1 CTCAE v5, acute skin toxicity (p = 0.18), Grade 1 Radiation Morbidity Scoring Scheme (RESS) subcutaneous tissue toxicity (p = 0.18), Grade 1 RESS late skin toxicity (p = 0.88) and cosmetic results (p = 0.46). Dosimetric results reveled that patients in 5 fraction group received significantly lower median ipsilateral lung doses (p < 0.01) in addition to left breast cancer patients that received significantly lower median heart dose (p < 0.01) and median left anterior descending artery (LAD) dose (p < 0.01). Conclusion: Ultra-hypofractionated radiotherapy for breast cancer is comparable to moderate hypofractionation regimen regarding grade 1 acute skin toxicity, grade 1 subcutaneous tissue toxicity, late skin toxicity and cosmetic results. Application of ultra-hypofractionated radiotherapy with significantly lower radiation doses for lung and heart could be crucial in reducing the risk of acute/late pulmonary and heart radiation-induced toxicity.

Association of 3D-CRT and IMRT accelerated hyperfractionated radiotherapy with local control rate and 5-year survival in esophageal squamous cell carcinoma patients

OBJECTIVES

This retrospective study examined the relevance and prognostic factors of whole-course conformal radiotherapy (CRT) and late-course accelerated hyperfractionation radiotherapy (LCAFRT) for esophageal squamous cell carcinoma (ESCC).

METHODS

A total of 110 patients with ESCC received whole-course CRT and LCAFRT between May 2004 and January 2015. All patients received conventional CRT of 2 Gy per day, up to 30-40 Gy, followed by LCAFRT using reduced fields at 1.5 Gy/fraction twice a day, up to 24-39 Gy, for a total dose of 60-69 Gy.

RESULTS

The median follow-up was 85 months. The whole groups 1-, 3-, and 5-year survival rates were 81.8%, 46.4%, and 41.8%, respectively. The local control rates for the whole group at 1, 3, and 5 years were 82.7%, 70.0%, and 68.2%, respectively. There were no significant differences among survival rates and local control rates between the 3D-CRT and intensity-modulated radiotherapy (IMRT) groups. The main reactions to acute radiotherapy were acute radiation tracheitis, esophagitis, and pneumonia. The tumor location and TNM stage were independent prognostic factors for overall survival.

CONCLUSION

The results showed that whole-course CRT and LCAFRT for ESCC can improve survival and local control with a tolerable acute reaction compared to previous studies. Local recurrence and distant metastasis are the main failure modes of treatment.

ADVANCES IN KNOWLEDGE

Whole-course CRT and LCAFRT for ESCC can improve the survival and local control rate compared with previous studies from the 2DRT era. It might provide another treatment for patients with inoperable ESCC or refusing surgery.

Evaluation of Patient-Reported Outcome Differences by Radiotherapy Techniques for Bone Metastases in A Population-Based Healthcare System

We assessed whether advanced RT techniques were associated with differences in patient-reported outcomes (PROs). Patients with bone metastases who completed the brief pain inventory (BPI) before and after RT were identified, and RT technique was categorized as simple (e.g., parallel opposed pair) or advanced (e.g., 3D-conformal RT (3DCRT), intensity-modulated RT (IMRT), or stereotactic ablative RT (SABR)). Pain response and patient-reported interference on quality of life secondary to pain was compared. A total of 1712 patients completed the BPI. From 2017−2021, the rate of advanced RT technique increased significantly (p < 0.001; 2.4%, 2.4%, 9.7%, 5.5%, 9.3%), with most advanced techniques consisting of IMRT, and only 7% of advanced techniques were SABR. Comparing simple vs. advanced technique, neither the complete pain response (12.3% vs. 11.4%; p = 0.99) nor the partial pain response (50.0% vs. 51.8%; p = 0.42) was significantly different. There was no significant patient-reported difference in pain interfering with general activity, mood, walking ability, normal work, relationships, sleep, or enjoyment of life. Given that there is increasing utilization of advanced RT techniques, there is further need for randomized trials to assess their benefits given the increased cost and inconvenience to patients.

Comparative Effectiveness Analysis of 3D-Conformal Radiation Therapy Versus Intensity Modulated Radiation Therapy (IMRT) in a Prospective Multicenter Cohort of Patients With Breast Cancer

PURPOSE

Simple intensity modulation of radiation therapy reduces acute toxicity compared with 2-dimensional techniques in adjuvant breast cancer treatment, but it remains unknown whether more complex or inverse-planned intensity modulated radiation therapy (IMRT) offers an advantage over forward-planned, 3-dimensional conformal radiation therapy (3DCRT).

METHODS AND MATERIALS

Using prospective data regarding patients receiving adjuvant whole breast radiation therapy without nodal irradiation at 23 institutions from 2011 to 2018, we compared the incidence of acute toxicity (moderate-severe pain or moist desquamation) in patients receiving 3DCRT versus IMRT (either inverse planned or, if forward-planned, using ≥5 segments per gantry angle). We evaluated associations between technique and toxicity using multivariable models with inverse-probability-of-treatment weighting, adjusting for treatment facility as a random effect.

RESULTS

Of 1185 patients treated with 3DCRT and conventional fractionation, 650 (54.9%) experienced acute toxicity; of 774 treated with highly segmented forward-planned IMRT, 458 (59.2%) did; and of 580 treated with inverse-planned IMRT, 245 (42.2%) did. Of 1296 patients treated with hypofractionation and 3DCRT, 432 (33.3%) experienced acute toxicity; of 709 treated with highly segmented forward-planned IMRT, 227 (32.0%) did; and of 623 treated with inverse-planned IMRT, 164 (26.3%) did. On multivariable analysis with inverse-probability-of-treatment weighting, the odds ratio for acute toxicity after inverse-planned IMRT versus 3DCRT was 0.64 (95% confidence interval, 0.45-0.91) with conventional fractionation and 0.41 (95% confidence interval, 0.26-0.65) with hypofractionation.

CONCLUSIONS

This large, prospective, multicenter comparative effectiveness study found a significant benefit from inverse-planned IMRT compared with 3DCRT in reducing acute toxicity of breast radiation therapy. Future research should identify the dosimetric differences that mediate this association and evaluate cost-effectiveness.

Estimating cancer risks due to whole lungs low dose radiotherapy with different techniques for treating COVID-19 pneumonia

BACKGROUND

Low dose radiotherapy (LDRT) of whole lungs with photon beams is a novel method for treating COVID-19 pneumonia. This study aimed to estimate cancer risks induced by lung LDRT for different radiotherapy delivery techniques.

METHOD

Four different radiotherapy techniques, including 3D-conformal with anterior and posterior fields (3D-CRT AP-PA), 3D-conformal with 8 coplanar fields (3D-CRT 8 fields), eight fields intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy using 2 full arcs (VMAT) were planned on the CT images of 32 COVID-19 patients with the prescribed dose of 1 Gy to the lungs. Organ average and maximum doses, and PTV dose distribution indexes were compared between different techniques. The radiation-induced cancer incidence and cancer-specific mortality, and cardiac heart disease risks were estimated for the assessed techniques.

RESULTS

In IMRT and VMAT techniques, heart (mean and max), breast (mean, and max), and stomach (mean) doses and also maximum dose in the body were significantly lower than the 3D-CRT techniques. The calculated conformity indexes were similar in all the techniques. However, the homogeneity indexes were lower (i.e., better) in intensity-modulated techniques (P < 0.03) with no significant differences between IMRT and VMAT plans. Lung cancer incident risks for all the delivery techniques were similar (P > 0.4). Cancer incidence and mortality risks for organs located closer to lungs like breast and stomach were higher in 3D-CRT techniques than IMRT or VMAT techniques (excess solid tumor cancer incidence risks for a 30 years man: 1.94 ± 0.22% Vs. 1.68 ± 0.17%; and women: 6.66 ± 0.81% Vs. 4.60 ± 0.43%: cancer mortality risks for 30 years men: 1.63 ± 0.19% Vs. 1.45 ± 0.15%; and women: 3.63 ± 0.44% Vs. 2.94 ± 0.23%).

CONCLUSION

All the radiotherapy techniques had low cancer risks. However, the overall estimated risks induced by IMRT and VMAT radiotherapy techniques were lower than the 3D-CRT techniques and can be used clinically in younger patients or patients having greater concerns about radiation induced cancers.

Preoperative chemoradiotherapy for locally advanced low rectal cancer using intensity-modulated radiotherapy to spare the intestines: a single-institutional pilot trial

The irradiated volume of intestines is associated with gastrointestinal toxicity in preoperative chemoradiotherapy for rectal cancer. The current trial prospectively explored how much of the irradiated volume of intestines was reduced by intensity-modulated radiotherapy (IMRT) compared with 3-dimensional conformal radiotherapy (3DCRT) and whether IMRT might alleviate the acute gastrointestinal toxicity in this population. The treatment protocol encompassed preoperative chemoradiotherapy using IMRT plus surgery for patients with clinical T3-4, N0-2 low rectal cancer. IMRT delivered 45 Gy per 25 fractions for gross tumors, mesorectal and lateral lymph nodal regions, and tried to reduce the volume of intestines receiving 15 Gy (V15 Gy) < 120 cc and V45 Gy ≤ 0 cc, respectively, while keeping target coverage. S-1 and irinotecan were concurrently administered. Acute gastrointestinal toxicity, rates of clinical downstaging, sphincter preservation, local regional control (LRC) and overall survival (OS) were evaluated. Twelve enrolled patients completed the chemoradiotherapy protocol. The volumes of intestines receiving medium to high doses were reduced by the current IMRT protocol compared to 3DCRT; however, the predefined constraint of V15 Gy was met only in three patients. The rate of ≥ grade 2 gastrointestinal toxicity excluding anorectal symptoms was 17%. The rates of clinical downstaging, sphincter preservation, three-year LRC and OS were 75%, 92%, 92% and 92%, respectively. In conclusion, preoperative chemoradiotherapy using IMRT for this population might alleviate acute gastrointestinal toxicity, achieving high LRC and sphincter preservation; although further advancement is required to reduce the irradiated volume of intestines, especially those receiving low doses.

Clinical practice of epidermal growth factor receptor-tyrosine kinase inhibitor targeted drugs combined with gadolinium oxide nanoparticles in the treatment of non-small cell lung cancer

It was to explore the clinical efficacy and safety of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) targeted drugs combined with hyaluronic acid-gadolinium sesquioxide-nanoparticles (HA-Gd2O3-NPs) in non-small cell lung cancer (NSCLC). In this study, 70 patients with stage IV EGFR mutant NSCLC diagnosed in the First Affiliated Hospital of Jinzhou Medical University were selected. They were randomly divided into the combined group (35 cases) and the control group (35 cases). HA-Gd2O3-NPs were prepared by hydrothermal polymerization, and combined with EGFR-TKI in the clinical treatment of NSCLC. The results showed that HA-Gd2O3-NPs were spherical with a uniform particle size of about 124 nm. The NSCLC survival rate of the combined group was 37.2 ± 5.3% under 6 Gy X-ray irradiation, and that of the control group was 98.4 ± 12.6% under 6 Gy X-ray irradiation. The total effective rate of the control group (20%) was significantly lower than that of the study group (42.86%) (P < 0.05). The one-year survival rate of the combined group (94%) was significantly higher than that of the control group (75%) (P < 0.05). The median progression-free survival (PFS) in the control group was 8 months, and that in the combined group was 12 months, with statistical difference (P < 0.05). EGFR-TKI targeted drugs combined with HA-Gd2O3-NPs can significantly improve the clinical efficacy of stage IV EGFR mutant NSCLC patients and benefit their survival.

Conformal radiotherapy in management of soft tissue sarcoma in adults

We present the update of the recommendations of the French society of radiation oncology on soft tissue sarcomas. Currently, the initial management of sarcomas is very important as it may impact on patients' quality of life, especially in limb soft tissue sarcomas, and on overall survival in trunk sarcomas. Radiotherapy has to be discussed within a multidisciplinary board meeting with results of biopsy, eventually reexamined by a dedicated sarcoma pathologist. The role of radiotherapy varies according to localization of soft tissue sarcoma. It is part of the standard treatment in grade 2 and 3 sarcomas of the extremities and superficial trunk>5cm. In case of R1 or R2 resection, reexcision should be discussed. In such cases, it may be delivered preoperatively (50Gy/25 fractions of 2Gy) or postoperatively. In retroperitoneal sarcomas, preoperative conformal radiotherapy with or without modulated intensity cannot be proposed systematically in daily practice. Concomitant chemoradiotherapy cannot be considered a standard treatment. Intensity-modulated radiotherapy has become widely available. Other soft tissue sarcoma sites such as trunk, head and neck and gynaecological soft tissue sarcomas will be addressed, as well as other techniques that may be used such as brachytherapy and proton therapy.

POstmastectomy radioThErapy in Node-posiTive breast cancer with or without Internal mAmmary nodaL irradiation (POTENTIAL): a study protocol for a multicenter prospective phase III randomized controlled trial

BACKGROUND

Various randomized trials have demonstrated that postmastectomy radiotherapy (RT) to the chest wall and comprehensive regional nodal areas improves survival in patients with axillary node-positive breast cancer. Controversy exists as to whether the internal mammary node (IMN) region is an essential component of regional nodal irradiation. Available data on the survival benefit of IMN irradiation (IMNI) are conflicting. The patient populations enrolled in previous studies were heterogeneous and most studies were conducted before modern systemic treatment and three-dimensional (3D) radiotherapy (RT) techniques were introduced. This study aims to assess the efficacy and safety of IMNI in the context of modern systemic treatment and computed tomography (CT)-based RT planning techniques.

METHODS

POTENTIAL is a prospective, multicenter, open-label, parallel, phase III, randomized controlled trial investigating whether IMNI improves disease-free survival (DFS) in high-risk breast cancer with positive axillary nodes (pN+) after mastectomy. A total of 1800 patients will be randomly assigned in a 1:1 ratio to receive IMNI or not. All patients are required to receive ≥ six cycles of anthracycline and/or taxane-based chemotherapy. Randomization will be stratified by institution, tumor location (medial/central vs. other quadrants), the number of positive axillary nodes (1-3 vs. 4-9 vs. ≥10), and neoadjuvant chemotherapy (yes vs. no). Treatment will be delivered with CT-based 3D RT techniques, including 3D conformal RT, intensity-modulated RT, or volumetric modulated arc therapy. The prescribed dose is 50 Gy in 25 fractions or 43.5 Gy in 15 fractions. Tiered RT quality assurance is required. After RT, patients will be followed up at regular intervals. Oncological and toxilogical outcomes, especially cardiac toxicities, will be assessed.

DISCUSSION

This trial design is intended to overcome the limitations of previous prospective studies by recruiting patients with pN+ breast cancer, using DFS as the primary endpoint, and prospectively assessing cardiac toxicities and requiring RT quality assurance. The results of this study will provide high-level evidence for elective IMNI in patients with breast cancer after mastectomy.

TRIAL REGISTRATION

ClinicalTrails.gov , NCT04320979 . Registered 25 Match 2020, https://clinicaltrials.gov/ct2/show/NCT04320979.

Could pulmonary low-dose radiation therapy be an alternative treatment for patients with COVID-19 pneumonia? Preliminary results of a multicenter SEOR-GICOR nonrandomized prospective trial (IPACOVID trial)

PURPOSE

To evaluate the efficacy and safety of lung low-dose radiation therapy (LD-RT) for pneumonia in patients with coronavirus disease 2019 (COVID-19).

MATERIALS AND METHODS

Inclusion criteria comprised patients with COVID-19-related moderate-severe pneumonia warranting hospitalization with supplemental O2 and not candidates for admission to the intensive care unit because of comorbidities or general status. All patients received single lung dose of 0.5 Gy. Respiratory and systemic inflammatory parameters were evaluated before irradiation, at 24 h and 1 week after LD-RT. Primary endpoint was increased in the ratio of arterial oxygen partial pressure (PaO2) or the pulse oximetry saturation (SpO2) to fractional inspired oxygen (FiO2) ratio of at least 20% at 24 h with respect to the preirradiation value.

RESULTS

Between June and November 2020, 36 patients with COVID-19 pneumonia and a mean age of 84 years were enrolled. Seventeen were women and 19 were men and all of them had comorbidities. All patients had bilateral pulmonary infiltrates on chest X‑ray. All patients received dexamethasone treatment. Mean SpO2 pretreatment value was 94.28% and the SpO2/FiO2 ratio varied from 255 mm Hg to 283 mm Hg at 24 h and to 381 mm Hg at 1 week, respectively. In those who survived (23/36, 64%), a significant improvement was observed in the percentage of lung involvement in the CT scan at 1 week after LD-RT. No adverse effects related to radiation treatment have been reported.

CONCLUSIONS

LD-RT appears to be a feasible and safe option in a population with COVID-19 bilateral interstitial pneumonia in the presence of significant comorbidities.

Radiation Therapy Techniques and Treatment-Related Toxicity in the PORTEC-3 Trial: Comparison of 3-Dimensional Conformal Radiation Therapy Versus Intensity-Modulated Radiation Therapy

PURPOSE

Radiation therapy techniques have developed from 3-dimensional conformal radiation therapy (3DCRT) to intensity modulated radiation therapy (IMRT), with better sparing of the surrounding normal tissues. The current analysis aimed to investigate whether IMRT, compared to 3DCRT, resulted in fewer adverse events (AEs) and patient-reported symptoms in the randomized PORTEC-3 trial for high-risk endometrial cancer.

METHODS AND MATERIALS

Data on AEs and patient-reported quality of life (QoL) of the PORTEC-3 trial were available for analysis. Physician-reported AEs were graded using Common Terminology Criteria for Adverse Events v3.0. QoL was assessed by the European Organisation for Research and Treatment of Cancer QLQC30, CX24, and OV28 questionnaires. Data were compared between 3DCRT and IMRT. A P value of ≤ .01 was considered statistically significant due to the risk of multiple testing. For QoL, combined scores 1 to 2 ("not at all" and "a little") versus 3 to 4 ("quite a bit" and "very much") were compared between the techniques.

RESULTS

Of 658 evaluable patients, 559 received 3DCRT and 99 IMRT. Median follow-up was 74.6 months. During treatment no significant differences were observed, with a trend for more grade ≥3 AEs, mostly hematologic and gastrointestinal, after 3DCRT (37.7% vs 26.3%, P = .03). During follow-up, 15.4% (vs 4%) had grade ≥2 diarrhea, and 26.1% (vs 13.1%) had grade ≥2 hematologic AEs after 3DCRT (vs IMRT) (both P < .01). Among 574 (87%) patients evaluable for QoL, 494 received 3DCRT and 80 IMRT. During treatment, 37.5% (vs 28.6%) reported diarrhea after 3DCRT (vs IMRT) (P = .125); 22.1% (versus 10.0%) bowel urgency (P = 0039), and 18.2% and 8.6% abdominal cramps (P = .058). Other QoL scores showed no differences.

CONCLUSIONS

IMRT resulted in fewer grade ≥3 AEs during treatment and significantly lower rates of grade ≥2 diarrhea and hematologic AEs during follow-up. Trends toward fewer patient-reported bowel urgency and abdominal cramps were observed after IMRT compared to 3DCRT.

Advanced radiotherapy technique in hepatocellular carcinoma with portal vein thrombosis: Feasibility and clinical outcomes

BACKGROUND

In Thailand, individuals with hepatocellular carcinoma (HCC) who develop portal vein tumor thrombosis (PVTT) have a restricted treatment option because to the extent of the disease, poor underlying liver function, and non-coverage of immuno/targeted therapy. Radiotherapy (RT) plays an increasingly important function in these patients. To investigate the feasibility, efficacy, and adverse event rates, we performed a retrospective analysis of patients with HCC with PVTT who underwent 3-dimensional conformal radiation (3DCRT), intensity-modulated radiation (IMRT), volumetric-modulated radiotherapy (VMAT), and stereotactic body radiotherapy (SBRT) in a single-institution.

OBJECTIVES

To examine clinical results in terms of overall survival (OS), local control (LC), response of primary tumor and PVTT, hepatic and gastrointestinal adverse reaction, and prognosis variables for OS and LC.

MATERIALS AND METHODS

Between July 2007 and August 2019, non-metastatic HCC with PVTT patients treated with RT were retrospectively reviewed and evaluated.

RESULTS

The analysis included data from 160 patients. The mean age of the patients was 60.8 years ((95% CI 58.2-62.0). The median diameter of the tumor was 7.7 cm (range: 1-24.5). 85 (54.5%) individuals had PVTT in the main or first branch. At 1.8-10 Gy per fraction, the mean biologically effective dose (BED) as α/β ratio of 10 was 49.6 (95% CI 46.7-52.5) Gy10. The median survival time was 8.3 (95% CI 6.1-10.3) months. Survival rates at one and two years were 39.6% and 17.1%, respectively. Estimated incidence of local failure using competing risk analysis were 24% and 60% at 1 and 2 years, respectively. The overall response rate was 74%, with an 18.5 percent complete response rate. In multivariate analysis, tumor size, overall response, and radiation dose were all significant prognostic variables for OS. Hepatic unfavorable events of grade 3 and 4 were for 14.1% of the total. There was no occurrences of grade 3-4 gastrointestinal toxicity, either acute or late. Additionally, there were no treatment-related mortality.

CONCLUSIONS

Advanced RT is regarded as a safe and effective therapeutic option for HCC with PVTT. Overall survival was clearly related to tumor size, radiation dose, and tumor/PVTT response. Individuals with BED 56 Gy10 had significantly better overall survival than patients with BED 56 Gy10. A prospective randomized trial is required to validate these outcomes in order to corroborate these findings.

Towards real-time PGS range monitoring in proton therapy of prostate cancer

Proton therapy of prostate cancer (PCPT) was linked with increased levels of gastrointestinal toxicity in its early use compared to intensity-modulated radiation therapy (IMRT). The higher radiation dose to the rectum by proton beams is mainly due to anatomical variations. Here, we demonstrate an approach to monitor rectal radiation exposure in PCPT based on prompt gamma spectroscopy (PGS). Endorectal balloons (ERBs) are used to stabilize prostate movement during radiotherapy. These ERBs are usually filled with water. However, other water solutions containing elements with higher atomic numbers, such as silicon, may enable the use of PGS to monitor the radiation exposure of the rectum. Protons hitting silicon atoms emit prompt gamma rays with a specific energy of 1.78 MeV, which can be used to monitor whether the ERB is being hit. In a binary approach, we search the silicon energy peaks for every irradiated prostate region. We demonstrate this technique for both single-spot irradiation and real treatment plans. Real-time feedback based on the ERB being hit column-wise is feasible and would allow clinicians to decide whether to adapt or continue treatment. This technique may be extended to other cancer types and organs at risk, such as the oesophagus.

[Rôle of radiotherapy for sarcomas]

The quality of the initial management of sarcomas is fundamental because it conditions the patient's quality of life and his overall survival. Radiotherapy should be discussed in a multidisciplinary consultation meeting within the framework of the Netsarc+network. The place of radiotherapy in patients with soft tissue or bone sarcoma depends on the histology and tumour location, knowing that it is most often associated with surgery which remains the main treatment. It is part of the standard treatment for grade II and III deep limb sarcomas of 5cm or greater in size and Ewing's sarcomas. In these indications, conformal radiotherapy with modulation of intensity is used routinely, in combination with IGRT. In other locations, such as retroperitoneal sarcomas or uterine sarcomas, radiotherapy is not a standard of care and must be discussed according to the prognostic criteria related to the patient, the tumour, and the previously received treatments. New techniques, such as proton therapy, hadron therapy (carbon ions) are techniques particularly suited to bone sarcomas considered to be radioresistant. However, large prospective trials are lacking in these rare indications, explaining the lack of recommendations of a high level of evidence.

Clinical Outcomes and Prognostic Factors in Gastric Carcinoma Patients with Curative Surgery Followed by Adjuvant Treatment: Real-World Scenario

BACKGROUND

A wide range of adjuvant treatment regimens exist in gastric carcinoma patients which include chemotherapy, radiotherapy, and/or both either sequential or concurrent. The study aimed to assess the benefit of adjuvant sequential chemotherapy followed by radiotherapy for operable gastric cancers and evaluate the prognostic factors associated with clinical outcomes.

METHODS

Patients of stage IB-III gastric carcinoma who underwent radical surgery followed by adjuvant treatment from January 2013 to December 2016 were analyzed retrospectively. Survival was computed using Kaplan-Meier method and prognostic factors were analyzed in multivariate analysis using Cox progression hazard model. A P value < 0.05 was taken as statistically significant.

RESULTS

A total of 108 patients were identified with a median follow-up of 31.7 months (range: 6-96). Seventy-two percent of the patients received adjuvant sequential chemoradiation (N = 77) and 28% of patients received chemotherapy alone. The median survival was 26 months (95% CI: 23.09-28.90). Overall survival (OS) rates for 1, 2, 3, 4, and 5 years were 88.9%, 57.4%, 40.7%, 28.8%, and 20.4%, respectively. Five-year OS for stage-IB, II, and III was 75%, 45%, and 8.3%, respectively (p = 0.023). Surgical margin positivity (9.5% vs. 26.9%, p = 0.042), signet-ring cell histology (6.5% vs. 25.8%, p = 0.00), and adjuvant sequential chemoradiation (p = 0.002) showed a significant impact on survival outcomes and proved as independent prognostic factors.

CONCLUSION

The present study demonstrated that survival in gastric carcinoma is influenced by the stage of disease and surgical margins. In locally advanced patients, radical surgery followed by sequential chemoradiation based on a doublet/triplet regimen was an independent prognostic factor for survival. Majority of patients in our set-up presented in locally advanced stage, curative resection followed by adjuvant sequential chemoradiation was an independent prognostic factor for survival.

Conventional 3D conformal radiotherapy and volumetric modulated arc therapy for cervical cancer: Comparison of clinical results with special consideration of the influence of patient- and treatment-related parameters

PURPOSE

Intensity-modulated radiotherapy (IMRT) for cervical cancer yields favorable results in terms of oncological outcomes, acute toxicity, and late toxicity. Limited data are available on clinical results with volumetric modulated arc therapy (VMAT). This study's purpose is to compare outcome and toxicity with VMAT to conventional 3D conformal radiotherapy (3DCRT), giving special consideration to the influence of patient- and treatment-related parameters on side effects.

MATERIALS AND METHODS

Patients with cervical cancer stage I-IVA underwent radiotherapy alone or chemoradiotherapy using 3DCRT (n = 75) or VMAT (n = 30). Survival endpoints were overall survival, progression-free survival, and locoregional control. The National Cancer Institute Common Terminology Criteria for Adverse Events and the Late Effects of Normal Tissues criteria were used for toxicity assessment. Toxicity and patient- and treatment-related parameters were included in a multivariable model.

RESULTS

There were no differences in survival rates between treatment groups. VMAT significantly reduced late small bowel toxicity (OR = 0.10, p = 0.03). Additionally, VMAT was associated with an increased risk of acute urinary toxicity (OR = 2.94, p = 0.01). A low body mass index (BMI; OR = 2.46, p = 0.03) and overall acute toxicity ≥grade 2 (OR = 4.17, p < 0.01) were associated with increased overall late toxicity.

CONCLUSION

We demonstrated significant reduction of late small bowel toxicity with VMAT treatment, an improvement in long-term morbidity is conceivable. VMAT-treated patients experienced acute urinary toxicity more frequently. Further analysis of patient- and treatment-related parameters indicates that the close monitoring of patients with low BMI and of patients who experienced relevant acute toxicity during follow-up care could improve late toxicity profiles.

Postoperative Radiotherapy for Locally Advanced NSCLC: Implications for Shifting to Conformal, High-Risk Fields

BACKGROUND

To examine the effect of radiotherapy field size on survival outcomes and patterns of recurrence in patients treated with postoperative radiotherapy (PORT) for non-small-cell lung cancer (NSCLC).

METHODS

We retrospectively reviewed the records of 216 patients with T1-4 N1-2 NSCLC following surgery and PORT using whole mediastinum (WM) or high-risk (HR) nodal fields from 1998 to 2015. Survival rates were calculated using the Kaplan-Meier method. Univariate and multivariable analyses were conducted using Cox proportional hazards modeling for outcomes and logistic regression analysis for treatment toxicities.

RESULTS

Median follow-up was 28 months (interquartile range [IQR] 13-75 months) and 38 months (IQR 19-73 months) for WM (n = 131) and HR (n = 84) groups, respectively. Overall survival (OS) was not significantly different between groups (median OS: HR 49 vs. WM 32 months; P = .08). There was no difference in progression-free survival (PFS), freedom from locoregional recurrence (LRR), or freedom from distant metastasis (P > .2 for all). Field size was not associated with OS, PFS, or LRR (P > .40 for all). LRR rates were 20% for HR and 26% for WM groups (P = .30). There was no significant difference in patterns of initial site of LRR between groups (P > .1). WM fields (OR 3.73, P = .001) and concurrent chemotherapy (odds ratio 3.62, P = .001) were associated with grade ≥2 toxicity.

CONCLUSIONS

Locoregional control and survival rates were similar between PORT groups; an improved toxicity profile was observed in the HR group. Results from an ongoing prospective randomized clinical trial will provide further insight into the consequences of HR PORT fields.

The impact of variable relative biological effectiveness in proton therapy for left-sided breast cancer when estimating normal tissue complications in the heart and lung

The aim of this study was to evaluate the clinical impact of relative biological effectiveness (RBE) variations in proton beam scanning treatment (PBS) for left-sided breast cancer versus the assumption of a fixed RBE of 1.1, particularly in the context of comparisons with photon-based three-dimensional conformal radiotherapy (3DCRT) and volumetric modulated arc therapy (VMAT). Ten patients receiving radiation treatment to the whole breast/chest wall and regional lymph nodes were selected for each modality. For PBS, the dose distributions were re-calculated with both a fixed RBE and a variable RBE using an empirical RBE model. Dosimetric indices based on dose-volume histogram analysis were calculated for the entire heart wall, left anterior descending artery (LAD) and left lung. Furthermore, normal tissue toxicity probabilities for different endpoints were evaluated. The results show that applying a variable RBE significantly increases the RBE-weighted dose and consequently the calculated dosimetric indices increases for all organs compared to a fixed RBE. The mean dose to the heart and the maximum dose to the LAD and the left lung are significantly lower for PBS assuming a fixed RBE compared to 3DCRT. However, no statistically significant difference is seen when a variable RBE is applied. For a fixed RBE, lung toxicities are significantly lower compared to 3DCRT but when applying a variable RBE, no statistically significant differences are noted. A disadvantage is seen for VMAT over both PBS and 3DCRT. One-to-one plan comparison on 8 patients between PBS and 3DCRT shows similar results. We conclude that dosimetric analysis for all organs and toxicity estimation for the left lung might be underestimated when applying a fixed RBE for protons. Potential RBE variations should therefore be considered as uncertainty bands in outcome analysis.

Impact of radiation techniques on lung toxicity in patients with mediastinal Hodgkin's lymphoma

PURPOSE

Mediastinal radiotherapy (RT), especially when combined with bleomycin, may result in substantial pulmonary morbidity and mortality. The use of modern RT techniques like intensity-modulated radiotherapy (IMRT) is gaining interest to spare organs at risk.

METHODS

We evaluated 27 patients who underwent RT for Hodgkin's lymphoma between 2009 and 2013 at our institution. For each patient, three different treatment plans for a 30-Gy involved-field RT (IFRT) were created (anterior-posterior-posterior-anterior setup [APPA], 5‑field IMRT, and 7‑field IMRT) and analyzed concerning their inherent "normal tissue complication probability" (NTCP) for pneumonitis and secondary pulmonary malignancy.

RESULTS

The comparison of different radiation techniques showed a significant difference in favor of standard APPA (p < 0.01). The risk of lung toxicity was significantly higher in plans using 7‑field IMRT than in plans using 5‑field IMRT. The absolute juxtaposition showed an increase in risk for radiation pneumonitis of 1% for plans using 5‑field IMRT over APPA according to QUANTEC (Quantitative Analyses of Normal Tissue Effects in the Clinic) parameters (Burman: 0.15%) and 2.6% when using 7‑field IMRT over APPA (Burman: 0.7%) as well as 1.6% when using 7‑field IMRT over 5‑field IMRT (Burman: 0.6%). Further analysis showed an increase in risk for secondary pulmonary malignancies to be statistically significant (p < 0.01); mean induction probability for pulmonary malignoma was 0.1% higher in plans using 5‑field IMRT than APPA and 0.19% higher in plans using 7‑field IMRT than APPA as well as 0.09% higher in plans using 7‑field IMRT than 5‑field IMRT. During a median follow-up period of 65 months (95% confidence interval: 53.8-76.2 months), only one patient developed radiation-induced pneumonitis. No secondary pulmonary malignancies have been detected to date.

CONCLUSION

Radiation-induced lung toxicity is rare after treatment for Hodgkin lymphoma but may be influenced significantly by the RT technique used. In this study, APPA RT plans demonstrated a decrease in potential radiation pneumonitis and pulmonary malignancies. Biological planning using NTCP may have the potential to define personalized RT strategies.

Outcome of Locally Advanced Esophageal Cancer Patients Treated With Perioperative Chemotherapy and Chemoradiotherapy Followed by Surgery

OBJECTIVES

Perioperative chemotherapy (P-CT) or neoadjuvant chemoradiation (C-RT) followed by surgical resection is the standard of care for locally advanced esophageal cancer (LAEC). We present an institutional review and outcome of patients with LAEC treated with neoadjuvant C-RT or P-CT followed by surgery.

METHODS

Patients were identified through the Manitoba Cancer Registry. Overall survival (OS), recurrence-free survival (RFS), and time to recurrence (TTR) were compared using proportion hazard regression analysis. Metabolic and pathologic response rates were compared by the Fisher exact test.

RESULTS

Sixty-seven patients were treated with C-RT and 32 with P-CT. Fifty-two percent of the patients had pretreatment and posttreatment positron emission tomography scans before surgery. Ninety-five percent of the patients in C-RT and 91% in P-CT had a partial metabolic response or stable disease. Sixty-one percent of C-RT and 34% of P-CT patients had tumor regression grade (TRG) 0 to 1; 39% of C-RT and 66% of P-CT had TRG 2 to 3 (P=0.018). Median OS was 37 and 18 months for patients with TRG 0 to 1 and 2 to 3, respectively (P=0.013, hazard ratio [HR]=1.96). Three-year OS was 43% versus 37% (P=0.37, HR=1.30), RFS was 34% versus 26% (P=0.87, HR=0.96), and median TTR was 30 versus 13 months (P=0.07, HR=0.59) for C-RT and P-CT, respectively.

CONCLUSIONS

C-RT was associated with a higher degree of pathologically tumor regression. Patients with major tumor regression had a better outcome than those with minimal to poor response. There was a trend toward improved TTR with C-RT but no difference in OS or RFS.