3-dimensional Conformal Radiotherapy Research Articles

A Prospective Cohort Study Analysing 3-Dimensional Conformal Radiotherapy and Salivary Glands Preserving Intensity Modulated Radiotherapy with/without Concomitant Cisplatin Chemotherapy in Head and Neck Malignancies

A Prospective Cohort Study Analysing 3-Dimensional Conformal Radiotherapy and Salivary Glands Preserving Intensity Modulated Radiotherapy with/without Concomitant Cisplatin Chemotherapy in Head and Neck Malignancies

Integrated IMRT vs segmented 3D-CRT of the chest wall and supraclavicular region for Breast Cancer after modified Radical Mastectomy: An 8-year follow-up.

Objective: The purpose of this study was to evaluate the efficacy of two radiotherapy techniques for breast cancer patients with post-mastectomy. The intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume was compared with the conventional segmented 3-dimensional conformal radiotherapy undergoing modified radical mastectomy.Materials and methods: Patients who received the two post-mastectomy radiation therapies were retrospectively analyzed. The chest wall and supra/infraclavicular region +/- internal mammary nodes were contoured as a whole planning target volume on the planning computed tomography. We evaluated differences in survival, recurrence, and late side effects between the integrated intensity-modulated radiotherapy group and the conventional segmented group.Results: A total of 223 patients were recruited. The mean follow-up was 104.3 months. Of these patients, 129 received integrated radiotherapy and 94 patients received segmented radiotherapy. The 8-year disease-free survival rates were 86.0% and 73.4% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.022). The 8-year overall survival rates were 91.4% and 86.2% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.530). Multivariate analysis demonstrated that radiotherapy was an independent prognostic factor for disease-free survival. No significant difference was observed in late side-effects between the two groups.Conclusion: Intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume reduces the recurrence rate for post-mastectomy breast cancer patients with tolerable toxicities.

Does Radiation Dose to Gastric Fundus during Neoadjuvant Chemoradiotherapy for Esophageal Carcinoma Have an Impact on Postoperative Anastomotic Leak?

Background: Radiation dose received by the gastric fundus (GF) in neoadjuvant chemoradiotherapy (NACRT) may influence the development of postoperative anastomotic leak (AL) in the management of resectable esophageal carcinoma (EC) by trimodality therapy. The present study aims to evaluate dose-volume parameters of the GF and their association with occurrence of AL in EC. Materials and Methods: A retrospective analysis was performed of 27 patients with EC who underwent NACRT followed by esophagectomy with cervical esophagogastric anastomosis between January 2015 and July 2018. The GF was retrospectively contoured; dose-volume parameters of the GF were recorded. Postoperative AL was identified from surgical records. Logistic regression analysis was used to identify risk factors associated with AL. Results: The mean age of the patients was 51 ± 10.5 years; 56% (15/27) had involvement of lower 1/3 esophagus, 10/27 (37%) midthoracic esophagus, and 2/27 (7%) upper thoracic esophagus; 40% (11/27) patients developed postoperative AL and 7/11 had distal and 4/11 had mid thoracic esophageal lesions. Four of five (80%) patients treated by 3-dimensional conformal radiotherapy versus 7/22 (32%) patients treated by volumetric modulated arc therapy developed AL (p = 0.12). Univariate logistic regression revealed no significant correlation between D_mean, D_max, V20, V25, V30, V35, D50, and AL. 8/27 patients underwent ischemic preconditioning of gastric conduit, and 2/8 had AL; 19/27 did not undergo preconditioning, and 9/19 patients experienced AL (p = 0.4). Conclusion: There was no significant negative impact of the dose received by the GF in NACRT upon AL rates. Further studies with a larger sample size are required to clarify this issue.

Study and Analysis of the Conformation Number and the Integral Dose as Evaluation Tools in Head and Neck Tumors: for Advanced 3-Dimensional Conformal Radiation Therapy Techniques

Study and Analysis of the Conformation Number and the Integral Dose as Evaluation Tools in Head and Neck Tumors: for Advanced 3-Dimensional Conformal Radiation Therapy Techniques

Quality of Life: A Prospective Randomized Trial of Palliative Volumetric Arc Therapy Versus 3-Dimensional Conventional Radiation Therapy

Volumetric arc therapy (VMAT) is a radiation therapy (RT) technique that spares normal tissues from high and intermediate RT doses but increases the volume of tissues receiving low doses of RT compared with 3-dimensional conformal RT (3DCRT). We hypothesized that palliative VMAT would reduce the detriment to patient quality of life (QOL) compared with palliative 3DCRT. This phase 2 trial randomized patients to palliative RT using VMAT or 3DCRT to 1 painful site of metastatic disease in the trunk. Treating physicians could choose 8 Gy in 1 fraction or 20 Gy in 5 fractions to stratify randomization. The primary endpoint was the change in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Version 3.0 (EORTC QLQ-C30) global health status QOL subscale at 1 week after RT. Repeated measures analysis of variance was used to assess the relationship of patient QOL over time with other factors. From July 2014 to November 2017, 37 patients who underwent 3DCRT and 32 patients who underwent VMAT were randomized into the study. Median overall survival was 9 months. Overall pain responses to RT were equivalent (P = .53) between the techniques. Patient compliance in returning QOL questionnaires was 94%, 81%, and 69% at baseline, 1 week after RT, and 1 month after RT, respectively. At 1 week after RT, change in global QOL was not significantly (P = .31) different between VMAT versus 3DCRT. At 4 weeks after RT, VMAT induced significantly (P = .049) less global QOL deterioration than 3DCRT did. Patients who underwent VMAT maintained better physical (P = .012), role (P = .041), and social (P = .025) functioning, but they reported more diarrhea symptoms (P = .017) than in the 3DCRT group. Palliative VMAT and 3DCRT did not differ in their ability to control pain; however, palliative VMAT induced fewer QOL detriments than 3DCRT did at 4 weeks after RT.

Dosimetric comparison of different radiotherapy techniques for the treatment of Retinoblastoma

AbstractAim:This study aims to compare the dosimetric parameters among four different external beam radiotherapy techniques used for the treatment of retinoblastoma.Materials and methods:Computed tomography (CT) sets of five retinoblastoma patients who required radiotherapy to one globe were included. Four different plans were generated for each patient using three dimensional conformal radiotherapy (3DCRT), intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and VMAT using flattening filter free (VMAT-FFF) beam techniques. Plans were compared for target coverage and organs at risk (OARs) sparing.Results:The target coverage of planning target volume (PTV) for all the four modalities were clinically acceptable with a V95 of 95 ± 0%, 97·6 ± 1·87%, 99·3 ± 0·5% and 99·17 ± 0·45% for 3DCRT, IMRT, VMAT and VMAT-FFF respectively. The VMAT and IMRT plans had better target coverage than the 3DCRT plans (p = 0·001 and p = 0·07 respectively). IMRT and VMAT plans were also found superior to 3DCRT plans in terms of OAR sparing like brainstem, optic chiasm, brain (p < 0·05). VMAT delivered significantly lower dose to the brainstem and contralateral optic nerve in comparison to IMRT. Use of VMAT-FFF beams did not show any benefit over VMAT in target coverage and OAR sparing.Conclusion:VMAT should be preferred over 3DCRT and IMRT for treatment of retinoblastoma owing to better target coverage and less dose to most of the OARs. However, IMRT and VMAT should be used with caution because of the increased low dose volumes to the OARs like contralateral lens and eyeball.

Verification and Evaluation of Radiation Doses received by organs at risk in (3D-CRT) and IMRT technique for breast cancer

External beam radiotherapy can be delivered more precisely by using three Dimensional Conformal Radiotherapy (3D-CRT) technique, which is a traditional method used for whole breast radiotherapy. 3D-CRT includes standard wedged tangents (two opposed wedged tangential photon beams), which is based on three Dimensional images (3D) from a special computed tomography (CT scan). Overseas notification form advent of CT scans and more powerful computers have improved dose calculation algorithms and Multi-leaf Collimators (MLCs). Consequently, 3D-CRT is able to shape the Radiotherapy Beam (RTB) closely to match the target shape and volume. Intensity Modulated Radiation Therapy (IMRT) technique has the ability to improve sparing of normal tissues and treatment results of radiotherapy (RT). RT is a standard adjuvant therapy in conservative treatment of breast cancer (BC). The IMRT technique is used for many treatment sites, allowing for improved normal tissue sparing, more conformal dose distributions and prevention of secondary cancer. The purpose of this study is to verify and evaluate between the outcome of Radiation Treatment Plans (RTP) of left-sided whole breast irradiation of IMRT technique, and 3D-CRT technique to organs at risk (OAR) that are proximal to the target volume during breast radiotherapy. These include left lung, right lung, heart, and spinal cord by different numbers of beam in left sided breast at Zhianawa cancer center (ZCC) – Sulaimany-KR-Iraq. A second aim is to establish a guideline for breast cancer radiotherapy planning at ZCC. Thirteen patients with left-sided, breast carcinoma who had received radiotherapy were selected for this study. The dose prescriptions for the patients were different according to each patient’s cancer stage, using 6, 18 MV photons. The clinical target volume [CTV] was contoured as a target volume and the contralateral breast, left lung, right lung, heart, and spinal cord tissues as OAR. The two different planning techniques were analyzed for 13 patients with left-sided breast conserving surgery. Plans were compared on the basis of planning target volume (PTV) dose conformity index (CI), homogeneity index (HI) and the volumes of normal tissues treated based on dose-volume histograms (DVHs). DVHs were calculated for the PTV, heart, left lung, right lung, spinal cord and soft tissue surrounding the breast PTV (VOB) volume. IMRT techniques slightly improved homogeneity ( HI) than 3D (0.16.04 vs. 0.22, p<0.068). However, there was no significant difference between IMRT and 3D-CRT plans regarding CI. No significant difference was noted in CI by 3D and IMRT as both showed similarity, p< 0.190 ); IMRT technique benefited patients more than 3D-CRT by reducing the high-dose (40.05 Gy) volume for the heart. The heart’s mean dose was significantly lower in 3D compared to IMRT (3.58 Gy vs. 10.07Gy, respectively; p < 0.0001). Both the mean dose of the left lung and right lung, were significantly lower for 3D compared to IMRT (10.18Gy vs. 14.26Gy and 0.34 vs. 4.17 respectively; p < 0.001), and p< 0.0001. Cord Max. Cord Max dose was significantly lower in 3D compared to IMRT (6.83Gy % vs. 20.89 Gy%, p < 0.0001). IMRT plans improved by increasing low-dose volume (Lift lung, and Spinal cord soft tissue surrounding the breast) compared with 3D-CRT plans (P<0.0001) but with Right lung P<0.575. However, 3D-CRT plans were improved by increasing low-dose volume (heart) compared with IMRT plans (P<0.230)

Accelerated partial breast irradiation with 3-dimensional conformal and image-guided intensity-modulated radiotherapy following breast conserving surgery – 7-Year results of a phase II trial

PurposeTo present the 7-year results of accelerated partial breast irradiation (APBI) using three-dimensional conformal (3D-CRT) and image-guided intensity-modulated radiotherapy (IG-IMRT) following breast-conserving surgery (BCS). Patients and methodsBetween 2006 and 2014, 104 patients were treated with APBI given by means of 3D-CRT using 3–5 non-coplanar, isocentric wedged fields, or IG-IMRT using kV-CBCT. The total dose of APBI was 36.9 Gy (9 × 4.1 Gy) using twice-a-day fractionation. Survival results, side effects and cosmetic results were assessed. ResultsAt a median follow-up of 90 months three (2.9%) local recurrences, one (0.9%) regional recurrence and two (1.9%) distant metastases were observed. The 7-year local (LRFS), recurrence free survival was 98.9%. The 7-year disease-free (DFS), metastases free (MFS) and overall survival (OS) was 94.8%, 97.9% and 94.8%, respectively. Late side effects included G1 skin toxicity in 15 (14.4%), G1, G2, and G3 fibrosis in 26 (25%), 3 (2.9%) and 1 (0.9%) patients respectively. Asymptomatic (G1) fat necrosis occurred in 10 (9.6%) patients. No ≥ G2 or higher late side effects occurred with IMRT. The rate of excellent/good and fair/poor cosmetic results was 93.2% and 6.8%, respectively. Conclusion7-year results of APBI with 3D-CRT and IG-IMRT are encouraging. Toxicity profile and local tumor control are comparable to other series using multicatheter interstitial brachytherapy. Therefore, these external beam APBI techniques are valid alternatives to whole breast irradiation and brachytherapy based APBI.

National, Observational, Multicentric Retrospective Study to Understand Treatment Patterns, Patient Journey and Characteristics with Stage III Non-Small Cell Lung Cancer Patients in Turkey: Stone Trial

In this multi-institutional study, we sought to investigate the contemporary treatment patterns of patients at initial and during first and second progression diagnosed with primary stage III NSCLC in Turkey. The patient characteristics, disease burden, treatment patterns and patient journey of stage III NSCLC patients were revealed. The clinical data of 492 patients treated between 2013 and 2017 were collected from geographically diverse set of ten community oncology centers in Turkey. The initial treatment included all treatment facilities after diagnosis. It includes chemotherapy (ChT) and radiotherapy (RT) delivered either sequentially or concurrently. These treatment patterns are analyzed at first treatment period, and during first and second progression periods. Median age was 64 years (range, 40 – 90 years). Most of the patients were male (434 patients, 88.2%) and were either past smoker or current smoker (462 patients, 93.9%). More than half of the patients (56.1%) had squamous cell carcinoma (SCC) and mean tumor size was 5.1±2.1 cm. According to the American Joint Committee on Cancer (AJCC) staging system 7th edition clinical stage IIIA (311 patients, 63.2%) was more frequently seen, and stage IIIB (278 patients, 56.5%) was most frequent when patients were staged according to AJCC 8th edition. For initial treatment 429 patients (89.2%) received ChT and RT, either concurrently (393 patients, 79.9%) or sequentially (46 patients, 9.3%), and only 53 patients (10.8%) were treated with RT only. Most frequently used RT technique was 3-dimensional conformal RT (3DCRT) (276 patients, 56.0%), while only 3 patients (0.6%) were treated with stereotactic radiotherapy (SBRT). Median 9.3 months after completion of initial treatment 288 patients (58.4%) had disease progression, and 166 patients (64.6%) received treatment). The main treatment modality at first progression was systemic treatment (121 patients, 72.9%), while 65 patients (37.1%) were treated with RT only. The RT treatment sites were mostly to the metastatic sites. The SBRT technique was used in 25 patients (22.2%). Disease progression was observed in 30 patients median 4.2 months (range, 0.8 – 11.4 months) after completion of treatment of first progression. Of these patients 20 patients (66.7%) received systemic therapy. The use of TKI and immunotherapeutic agent was quite limited in this cohort during initial treatment, first and second progression time. In the initial treatment period, none of the patients received TKI and immunotherapy. Only 7 patients (5.8%) received TKI and 3 patients (2.5%) had immunotherapeutics during first progression interval. At second progression only 2 patients (1%) received TKI and immunotherapy separately. This national observational study showed that the majority of patients with unresectable stage III NSCLC received cCRT as the first therapy, and this practice was consistent with guidelines.

Radiation-Induced Lymphopenia Correlates With Survival In Nasopharyngeal Carcinoma: Impact Of Treatment Modality And The Baseline Lymphocyte Count

We evaluated the relationship between patient-, tumor-, and treatment-related features and radiation-induced lymphopenia (RIL) and evaluated the correlation between RIL and survival outcome in NPC patients to help improve the treatment strategy. This retrospective study included 374 patients with stage II-IVa NPC who had been treated with definitive RT and were enrolled from 2004 to 2015; The associations between the G3–4 RIL (absolute lymphocyte count, ALC < 0.5 × 109 cells/L) during RT and patient-, tumor-, and treatment-related factors were assessed using Cox regression analyses. The correlation between ALC nadir and survival was examined using a Kaplan-Meier analysis, compared with the log-rank test, and confirmed by a Cox proportional hazards analysis. In the multivariate analysis, lower baseline ALC and intensity modulated radiation therapy (IMRT) (vs. 2 dimensional-conformal radiation therapy,2D-CRT) were identified as 2 independent factors that were associated with G3–4 RIL. In the multivariate survival analysis, patients with G3–4 ALC nadir had longer local recurrence-free survival durations (LRFS) (vs. G0–2 nadir, HR = 0.548, P = 0.005) and longer progression-free survival durations (PFS) (vs. G0–2 nadir, HR = 0.676, P = 0.022), while patients with G4 ALC nadir had a shorter distant-metastasis-free survival duration (DMFS) (vs. G0–2 nadir, hazard ratio [HR] = 2.567, P = 0.037). In the study, lymphopenia during RT were affected by baseline ALC and RT modality independently. Moreover, G3–4 ALC nadir was independently linked with longer PFS and LRFS durations, while G4 ALC nadir was independently linked with a shorter DMFS duration.

Patient-Reported Outcomes in Prospective Cohort of Patients with Borderline Resectable or Locally Advanced Pancreatic Cancer Undergoing Radiotherapy

Among patients with pancreatic cancer, radiotherapy has a role in offering patients local and overall control but data on patient reported outcomes remains scarce. We sought to quantify the patient reported outcomes (PROs) of pancreatic cancer patients receiving radiotherapy (RT) in order to improve patient-physician communication and shared decision making. As part of an IRB-approved study, we prospectively collected PRO data for 57 patients (28 male, 29 female, median age of 68 years [range, 41-83]) with non-metastatic pancreatic cancer who were treated with neoadjuvant chemotherapy (50% FOLFIRINOX, 42% gemcitabine and nab-paclitaxel, 8% other) and RT. Patients received stereotactic body radiation therapy (SBRT) (median dose: 36Gy, 5 fractions for all, n = 13), volumetric modulated arc therapy (VMAT) (median dose: 50.4Gy, 10-28 fractions, n = 20), intensity-modulated radiation therapy (IMRT) (median dose: 62Gy, 10-28 fractions, n = 13), or 3-dimensional conformal radiation treatment (3D-CRT) (median dose: 30Gy, 10-28 fractions, n = 13). All patients were seen by a multidisciplinary care team. PROs were collected using the validated MD Anderson Symptom Inventory for gastrointestinal cancer (MDASI-GI) questionnaire before the start of RT and after completion of RT. We used descriptive statistics to summarize the patients’ characteristics and MDASI-GI scores. We then performed subgroup analyses on the different radiation modalities and used the paired t-test to compare mean between pre-, and post-RT MDASI-GI scores. Median follow up time was 14.0 months and median overall survival was 24.4 months. No significant differences between pre-, and post-RT were found for the composite MDASI-GI score (mean difference: 0.04, 95% CI [-0.23 – 0.32], p = 0.76). Furthermore, there was no significant differences between pre-, and post- therapy for each radiation modality used. The 5 most-severe MDASI-GI items were fatigue, mouth dryness, numbness, taste disturbance, and decreased appetite. Compared to baseline, no increase in the proportion of patients reporting moderate to severe MDASI-GI items was noted in the IMRT group. In the 3D-CRT group, there was no increase in the proportion of patients reporting moderate to severe MDASI-GI items except for appetite (10% increase). Similarly, no change was noted in the SBRT and VMAT groups except for numbness (16% increase) and mouth dryness (8% increase) respectively. Different RT modalities do not seem to affect PROs in a clinically significant way for patients with pancreatic cancer. This may be related to modern medical management and newer radiation technologies. Future studies will investigate additional time points and correlate PRO data with outcomes.

Cost-Effectiveness of PET-Directed vs. Combined Modality Therapy for Early Stage Hodgkin Lymphoma

The standard of care for early-stage Hodgkin Lymphoma (HL) is combined modality therapy (CMT) consisting of chemotherapy and involved site radiation therapy (ISRT). Due to concerns that the combination of chemotherapy and radiotherapy is more harmful than chemotherapy alone, several trials have assessed the impact of omitting radiation with the use of positron emission tomography (PET). PET is considered useful in identifying patients at low risk for disease recurrence. These studies have suggested a detriment in progression free survival (PFS) for patients who do not receive ISRT but similar overall survival. The purpose of this study was to compare the cost-effectiveness of PET-directed therapy vs. standard of care CMT. This economic evaluation used a cost-effectiveness model simulating 5-year outcomes for 1 million patients with early-stage HL treated with either PET-directed therapy consisting of 2 cycles of Adriamycin, Bleomycin, Vincristine, and Dacarbazine (ABVD) +/- 20 Gy ISRT or CMT consisting of 2 cycles of ABVD + 20 Gy ISRT. Patients entered the model with early-stage favorable HL and received either PET-directed therapy or CMT. Patients progressed to no evidence of disease (NED), disease progression (DP), or death. Patients with DP underwent salvage therapy with high dose chemotherapy and stem cell transplant (HDC-SCT). Health utilities were obtained from published studies and transition probabilities were derived from the GHSG HD16 trial. Costs were obtained from the Healthcare Bluebook and 2019 National Medicare fee schedules. For the base case analysis, we assumed 3-dimensional conformal radiation treatment. Utilities and costs were discounted at 3% annually. The primary outcome measured was the incremental cost-effectiveness ratio (ICER); we defined the willingness-to-pay (WTP) threshold at $100,000 per quality-adjusted life-year (QALY). Deterministic sensitivity analyses were performed to assess for uncertainty around model parameters. We found that PET-directed therapy and CMT strategies were associated with costs of $42,536 and $37,931, respectively. The CMT strategy was slightly more effective than the PET-directed therapy strategy with QALYs of 2.947 and 2.945, respectively. As CMT was both less expensive and more effective as compared to PET-directed therapy, CMT was the dominant strategy. On one-way sensitivity analyses, the model was most sensitive to costs of ABVD, ISRT, and HDC-SCT salvage treatment. Three-way sensitivity analyses showed that the model was also sensitive to the relative costs of these treatments. For patients with early-stage favorable HL requiring definitive treatment, CMT is the cost-effective strategy as compared with PET-directed therapy. These results should be used to inform the ongoing debate regarding the role of ISRT and PET in the treatment of early-stage favorable HL.

Intensity-modulated Radiation Therapy (IMRT) May Reduce Diarrhea With Similar Treatment Efficacy Even In Japanese Treatment Strategy For Cervical Cancers

The RTOG 1203 trial showed that IMRT after hysterectomy could reduce acute radiation enteritis (ARE) compared to 3-dimensional conformal radiotherapy (3DCRT). However, it should be investigated whether IMRT could reduce ARE in radical radiotherapy for cervical cancers, considering the inter- and intra-fractional motions of the uterus (5-15 mm) and larger target volume. In Japan, treatment strategy for cervical cancers differs from that of other countries. The intestine is shielded during whole-pelvic irradiation (WPI) and brachytherapy starts earlier. Thus, even in 3DCRT, the ARE incidence can be lower than in other countries. We applied radical IMRT for cervical cancers using tomotherapy and investigated whether the IMRT protocol could reduce ARE and other toxicities. We reviewed patients with cervical cancers treated at 3 institutions that employed the same protocol. In the protocol, patients with UICC 8th stage IB-IVA cervical cancers received radical WPI ± paraaortic irradiation with 45-50.4 Gy delivered at a daily fraction of 1.8 Gy five times a week. Platinum-containing chemotherapy was delivered to ≥ stage III or tumors with ≥ 4 cm in the maximum diameter. After 20-30 Gy of WPI depending on the stage, the rectum, bladder and intestine were shielded and intracavitary brachytherapy (2-4 times at a point A dose of 5-6 Gy) was carried out. In IMRT, a block structure was contoured instead of the center shielding in 3DCRT. The block structure median dose was reduced to ≤ 0.9 Gy/fr. From 2007 to 2011, 3DCRT was used. From 2012, the IMRT protocol was introduced. We compared the IMRT and 3DCRT groups. All patients treated with the protocols were analyzed except patients with: 1) previous history of hysterectomy or radiotherapy and 2) small cell cancer. ARE was defined as the increase in stool of 4–6 times per day over the baseline. In total, 169 patients were treated according to the protocols. Of them, IMRT was delivered to 93 (median age, 63 years) and 3DCRT to 76 (61 years). Chemotherapy was administered to 73 in the IMRT group and 50 in the 3DCRT group (p = 0.08). Lymph node metastases were seen in 44 in the IMRT group and 26 in the 3DCRT group (p = 0.12). The 3-year overall survival and locoregional recurrence rates after IMRT were 84% and 17%, respectively. In the 3DCRT group, these rates were 70% and 20%, respectively. No difference was seen between the 2 groups (p > 0.2). ARE occurred less frequently in the IMRT group than in the 3DCRT group (17/93 vs 24/76, p < 0.05). Grade 3 toxicities were observed in 5 in the IMRT group (rectal bleeding 2, sigmoid colon stenosis 1, bladder tamponade 2) and in 3 in the 3DCRT group (rectal bleeding 1, small intestinal perforation 2) (p = 0.73). There was no ≥ grade 4 toxicity in both groups. Even in the Japanese treatment strategy for cervical cancers, use of IMRT may reduce ARE with similar treatment efficacy.

Comparing Accuracy of Thermoplastic Mask versus Commercial Bra for the Immobilization of Pendulous Breast During Radiation Therapy Treatment: A Retrospective Cohort Study

PurposeThis study aimed to compare thermoplastic mask with bra in terms of setup reproducibility and immobilization of pendulous breasts during radiation therapy (RT). Methods and materialsForty-two female patients with breast cancer treated with either intensity modulated RT or 3-dimensional conformal RT were retrospectively reviewed. Of these, 21 benefited from thermoplastic mask immobilization and 21 used a bra. Setup accuracy was evaluated using consecutive cone beam computed tomography/electronic portal imaging device sessions over the first 3 days before treatment (systematic setting), followed by weekly cone beam computed tomography/electronic portal imaging device (random settings), and compared with the reference image to calculate the corresponding translational shift (setup error) in the 3 planes. Average absolute shift values in both systematic and random settings were compared between the 2 groups. Accuracy was analyzed by comparing the percentage of pooled settings within ±0.05 and ±0.1 cm of the reference image. ResultsCompared with a bra, use of the mask was associated with a smaller longitudinal shift in systematic settings (difference in mean: 0.27 cm; P = .027; Mann-Whitney U test) and a lesser lateral shift in random setting (difference in mean: 0.19 cm; P = .005; Mann-Whitney U test). In the pooled systematic settings, the mask performed relatively better than the bra in the lateral and longitudinal planes, with no statistical significance. In pooled random settings, mask showed greater accuracy than bra in the lateral plane with 86.0% versus 58.9% accuracy at ±0.5 cm (P < .001) and 48.8% versus 21.7% accuracy at ±0.1 cm (P < .001), respectively. There was no significant difference in the incidence of radiodermatitis between the 2 groups. However, a hypofractionation regimen was associated with a lower incidence of radiodermatitis, and the severity of skin reactions was positively correlated with treatment dose (unstandardized regression coefficient: B = .001; correlation coefficient: r = .571; P < .001). ConclusionsMasks provide superior reproducibility compared with commercially available bras.

Stage III Esophageal Squamous Cell Carcinoma Patients With Three-Dimensional Conformal or Intensity-Modulated Radiotherapy: A Multicenter Retrospective Study.

Aim: To evaluate long-term outcome and prognostic factors of stage III esophageal cancer after definitive radiotherapy using three dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) techniques.Methods: Patients with T3N1M0/T4N0-1M0 esophageal squamous cell carcinoma (ESCC) treated with definitive radiotherapy from 2002 to 2016 in 10 Chinese medical centers were retrospectively analyzed. Overall survival (OS) and progression-free survival (PFS) rates were calculated. Prognostic factors were analyzed by Log-rank test and multivariable Cox model.Results: Survival data of 1,450 patients were retrospectively collected. With a median follow-up time of 65.9 months, 1-, 3-, and 5-year OS rates were 69.3, 36.7, and 27.7%, respectively, and PFS rates were 58.6, 32.7, and 27.4%, respectively. Univariable analyses showed that gender, age, lesion location, lesion length, largest tumor diameter, lymph node metastasis, gross tumor volume, EQD2, short-term response, and concurrent chemotherapy were prognostic factors for OS. Multivariable analyses showed that lesion location, T-classification, GTV size, EQD2, and short-term response to RT were independent prognostic factors for OS, and tumor diameter, GTV size, and short-term response were independent prognostic factors for PFS.Conclusions: This study demonstrated that definitive radiotherapy using 3DCRT and IMRT provides promising outcomes for locally advanced ESCC.

Dosimetric comparison of 3-dimensional conformal radiotherapy (3D-CRT) and volumetric-modulated arc therapy (VMAT) in locally advanced cancer cervix

AbstractIntroduction:Dosimetric advantages of volumetric-modulated arc therapy (VMAT) over three-dimensional conformal radiotherapy (3D-CRT) are not established in a head-on comparison of a uniform group of locally advanced carcinoma of the cervix (LACC). Therefore, we conducted a dosimetric comparison of these two techniques in LACC patients.Materials and methods:Computed tomography (CT) data of histologically proven de novo LACC, including Stage IIB–IIIB and earlier stages deemed inoperable, were included in this prospective observational dosimetric study. Planning was initially done by 3D-CRT technique (dose of 45–50·4 Gy @ 1·8–2 Gy/# was used in the actual treatment), followed by VMAT planning and appropriate dosimetric comparisons were done in 39 cases.Results:For planning target volume coverage, D95, D98 and D100 (p &lt; 0·0001 for all parameters) and V95 and V100 (p = 0·002 and &lt;0·0001, respectively) were significantly improved with VMAT. The conformity index (CI) was significantly better with VMAT (p = 0·03), while 3D-CRT had a significantly better homogeneity index (HI)(p = 0·003). Dose to the urinary bladder was significantly reduced with VMAT compared to 3D-CRT for V20–V50, except V10. The doses to the rectum and abdominal cavity were significantly reduced with VMAT compared to 3D-CRT plans for all parameters (V10–V50). The number of organs at risks (OARs) for which constraints were met was higher with VMAT plans than with 3D-CRT plans, with at least four out of the five OARs protected in 46·1 versus 5·1% and all constraints achieved in 15·4% versus none.Conclusion:We conclude that in dosimetric terms, VMAT is superior to 3D-CRT for LACC.

Bibliometric analysis of the 100 most cited articles on cervical cancer radiotherapy.

Purpose:To identify the 100 most cited research articles on cervical cancer radiotherapy.Methods:The Web of Science and Scopus databases were searched to identify the 100 most cited articles on cervical cancer radiotherapy as of September 29, 2019. Articles were ranked based on the total citations received from 2 databases. One hundred articles about radiotherapy for cervical cancer were identified. The following important information was extracted: author, journal, year and month of publication, country or region, and radiotherapy technologies.Results:The 100 most cited articles on cervical cancer radiotherapy were published between 1964 and 2016, and the total citations from 2 databases ranged from 3478 to 211, including a total of 49,262 citations as of September 29, 2019. The index of citations per year ranged from 170.4 to 13.1. These articles were from 16 countries or regions, with most publications being from the United States (n = 38), followed by Austria (n = 15), Canada (n = 8), France (n = 8) and the United Kingdom (n = 7). The International Journal of Radiation Oncology, Biology, Physics produced the most articles (n = 42), followed by Radiotherapy and Oncology (n = 13), Cancer (n = 8) and Journal of Clinical Oncology (n = 7). These articles were categorized as original studies (n = 86), recommendations (n = 5), guidelines (n = 5) and reviews (n = 4). Of the 100 most cited articles, intracavitary brachytherapy (n = 50) and 3-dimensional conformal radiotherapy (n = 34) were the most commonly used treatment techniques.Conclusion:To the best of our knowledge, this is the first report and analysis of the most cited articles on cervical cancer radiotherapy. This bibliographic study presents the history of technological development in external radiation therapy and brachytherapy. Brachytherapy is an indispensable part of radiotherapy for cervical cancer. The International Journal of Radiation Oncology Biology Physics is the journal with the most publications related to cervical cancer radiotherapy.

Postoperative radiotherapy with intensity-modulated radiation therapy versus 3-dimensional conformal radiotherapy in early breast cancer: A randomized clinical trial of KROG 15-03

PurposeTo investigate the safety and efficacy of intensity-modulated radiation therapy (IMRT) for early breast cancer compared with 3-dimensional conformal radiotherapy (3D-CRT) in a prospective and randomized trial. Methods and materialsFrom March 2015 to February 2018, 693 patients with pT1-2N0M0 early breast cancer who underwent breast-conserving surgery were enrolled and randomly assigned into IMRT and 3D-CRT. The primary endpoint was 3-year locoregional recurrence-free survival (LRRFS). The secondary endpoints were recurrence-free survival, overall survival, acute toxicity, target coverage index, irradiation dose to organs at risk, and fatigue inventory. The radiation dose for the 3D-CRT arm was 59.4 Gy in 33 fractions for 6.5 weeks. It was 57.4 Gy in 28 fractions with simultaneous integrated boost for 5.5 weeks for the IMRT arm. ResultsOf 693 patients, 349 and 344 patients received 3D-CRT and IMRT, respectively. There was no significant difference in LRRFS between the two arms. Conformity index of planning target volume was significantly superior in the IMRT arm than the 3D-CRT arm (p < 0.001). The mean lung dose and V5-V50 for the ipsilateral lung were significantly lower in the IMRT arm than the 3D-CRT arm (all p < 0.05). The incidence of grade 2 or higher dermatitis was significantly lower in the IMRT arm (p = 0.009). ConclusionCompared to 3D-CRT, IMRT showed similar results in locoregional tumor control but superior results in planning target volume coverage. When IMRT is used in breast cancer, the irradiation dose to an ipsilateral lung and skin toxicity can be reduced.

Phase II Study: The Outcome of Hypofractionated Involved-Field Radiation Therapy With Concurrent Chemotherapy for the Treatment of Locally Advanced Non-small Cell Lung Cancer

PurposeThis phase II study aimed to evaluate the efficacy and safety of hypofractionated involved-field radiation therapy (HypoFx-IFRT) in 2.5 Gy fractions and concurrent chemotherapy for locally advanced stage IIIA and B nonsmall cell lung cancer (LA-NSCLC) without prolonging treatment delivery time beyond 6 weeks. We analyzed the overall survival (OS), progression-free survival, and safety of the treatment. Methods and MaterialsThis prospective, single center, single-arm trial was initiated in 2010. All LA-NSCLC patients were treated with HypoFx-IFRT using 3-dimensional conformal radiation therapy. The median total dose of HypoFx-IFRT was 67.5 Gy (range, 60-70). ResultsFrom December 2010 to October 2016, 36 patients were ultimately enrolled and evaluated. The trial closed early owing to slow accrual. The median follow-up duration was 50 months in all patients and 65 months in surviving patients. The 1-, 3-, and 5-year OS rates were 88.9% (95% confidence interval [CI], 78.6%-99.2%), 61.1% (95% CI, 45.2%-77.0%), and 54.1% (95% CI, 37.3%-70.9%), respectively. The median time for OS was not reached. The median time for progression-free survival was 10.7 months. The incidence rates of grade 3 radiation pneumonitis, esophagitis and esophageal stenosis were 8.3%, 2.8%, and 2.8%, respectively, and no acute or late toxicities of grade 4 or 5 were observed. ConclusionsThis study indicated that HypoFx-IFRT with concurrent chemotherapy yielded an acceptable safety profile and might be beneficial in the survival outcomes of patients with LA-NSCLC.

Dosimetric Evaluation of 3-Dimensional Conformal Radiotherapy Technique in Postoperative Patients with Gastric Carcinoma: When Is IMRT Really Needed?

Background and purpose: Adjuvant Chemoradiotherapy is the standard of care for postoperative gastric cancers with high risk features. The purpose of the current study is to do a dosimetric analysis in the postoperative setting by using 3-Dimensional Conformal Radiotherapy (3D-CRT) to a total dose of 45 Gy in 25 fractions over 5 weeks. A subsequent comparison with the 3D-CRT and IMRT of other published data is presented.Materials and Methods: Sixty postoperative patients who underwent radiation with 3D-CRT technique were included in this analysis. All patients received concurrent 5-Flurouracil or Capecitabine chemotherapy along with radiation. Radiation plans were analysed in terms of PTV coverage, conformity index (CI), homogeneity index (HI), organs at risk (OARs) and dose volume histogram (DVH) parameters. Results: DVH statistics for PTV: Dmean was 45.2±0.8 Gy, D98 was 42.9 ±1 Gy, D95 was 43.4±0.8 Gy, and D2 was 47.7±1.1 Gy. Mean CI for all plans was 1.23±0.43 and HI was 1.09±0.03. DVH parameters for OARs: right kidney, Dmean = 11.9±5.1 Gy, V18 was 21.5±13.8%, V15 was 27.2±14.9% and left kidney, Dmean was 17.7±5.8 Gy, V18 was 33.5±13.8%, V15 was 43.2±15.5%. Dmean for liver was 27.7±6.4 Gy and V20 was 69.2±15.8%. D195cc for the bowel bag was 36.3±10.8 Gy. Conclusion: The results of this study and subsequent comparison with existing literature suggests that 3D-CRT provides adequate homogenous target volume dose coverage and OAR protection, comparable to IMRT. More than the radiotherapy technique, it was the anastomotic site and the tumor location that determined the OAR doses.