Reports of Practical Oncology and Radiotherapy最新文献

Background: The GI Tumors Workgroup, a division of the Spanish Society of Radiation Therapy, conducted a survey in December 2020 to assess the adherence of radiation oncologists in Spain to international guidelines for gastrointestinal tumors.

Materials and methods: Using Google Forms, we designed a survey covering treatments for esophageal, gastric, pancreatic, and rectal cancers.

Results: In esophageal cancer treatment, neoadjuvant chemoradiation was the standard in 76.7% of institutions. Radiation doses range from 41.1 to 50.4 Gy in conventional fractionation. Planning positron emission tomography-computed tomography (PET-CT) was performed in 83.3% of centers, and intensity-modulated radiation therapy/volumetric-arc radiation therapy (IMRT/VMAT) was the preferred technique in 86.7% of institutions. For gastric cancer, 71.4% followed perioperative chemotherapy guidelines. In the case of adjuvant radiotherapy, the majority prescribed 45-50.4 Gy, and 82.1% used IMRT/VMAT for treatment. For pancreas cancer, neoadjuvant chemotherapy followed by surgery in borderline resectable tumors and induction chemotherapy followed by radical radiotherapy for non-resectable tumors were the most frequent approaches. IMRT/VMAT was the primary technique. Locally advanced rectal cancer treatment is mainly based on neoadjuvant radiotherapy in all institutions. The preferred radiation doses typically range from 45 to 50 Gy in conventional fractionation. IMRT/VMAT was standard in most Institutions.

Conclusions: Spain's radiotherapy practices among respondents generally align with international guidelines for GI tumors highlighting Spain's commitment to evidence-based medical practice.

Background: Part of the current stereotactic arrythmia radioablation (STAR) workflow is transfer of findings from the electroanatomic mapping (EAM) to computed tomography (CT). Here, we analyzed inter- and intraobserver variation in a modified EAM-CT registration using automatic registration algorithms designed to yield higher robustness.

Materials and methods: This work is based on data of 10 patients who had previously undergone STAR. Two observers participated in this study: (1) an electrophysiologist technician (cardiology) with substatial experience in EAM-CT merge, and (2) a clinical engineer (radiotherapy) with minimum experience with EAM-CT merge. EAM-CT merge consists of 3 main steps: segmentation of left ventricle from CT (CT LV), registration of the CT LV and EAM, clinical target volume (CTV) delineation from EAM specific points. Mean Hausdorff distance (MHD), Dice Similarity Coefficient (DSC) and absolute difference in Center of Gravity (CoG) were used to assess intra/interobserver variability.

Results: Intraobserver variability: The mean DSC and MHD for 3 CT LVs altogether was 0.92 ± 0.01 and 1.49 ± 0.23 mm. The mean DSC and MHD for 3 CTVs altogether was 0,82 ± 0,06 and 0,71 ± 0,22 mm. Interobserver variability: Segmented CT LVs showed great similarity (mean DSC of 0,91 ± 0,01, MHD of 1,86 ± 0,47 mm). The mean DSC comparing CTVs from both observers was 0,81 ± 0,11 and MHD was 0,87 ± 0,45 mm.

Conclusions: The high interobserver similarity of segmented LVs and delineated CTVs confirmed the robustness of the proposed method. Even an inexperienced user can perform a precise EAM-CT merge following workflow instructions.

Background: Craniospinal irradiation (CSI) is a complex radiotherapy (RT) technique required for treating specific brain tumors and some hematologic malignancies. With large volumes of hematogenous bone marrow (BM) being irradiated, CSI could cause acute hematologic toxicity, leading to treatment interruptions or severe complications. We report on the dynamics and dose/volume predictors of hematologic toxicity during CSI.

Materials and methods: Pediatric patients (≤ 18years) undergoing CSI in a tertiary cancer center were included. Medical records were retrospectively reviewed for clinical data and blood parameters were collected at baseline and weekly, until four weeks after the end of RT. The BM substructures were contoured, and dose-volume parameters were extracted. We used Wilcoxon rank-sum test to compare quantitative data, Chi square test for qualitative data and receiver operating characteristics (ROC) curves for dose/volume thresholds.

Results: Fifty-one patients were included. Severe toxicities (grade 3-4) were recorded as follows: 2% anemia, 8% thrombocytopenia, 25% leukopenia, 24% neutropenia. Ninety-eight percent of patients had lymphopenia (grade 1-4) at some point. Twenty-nine percent required granulocyte-colony stimulating factor, 50% had an infection and 8% required a blood transfusion. Dmean > 3.6 Gy and V15 Gy > 10.6% for Pelvic Bones were associated with a higher risk of developing any ≥ G3 toxicities. Dmean > 30-35 Gy to the thoracic and lumbar spine was predictive for G3-4 anemia and thrombocytopenia, and Cervical Spine Dmean > 30 Gy was associated with ≥ G3 neutropenia.

Conclusion: CSI was well tolerated, without life-threatening complications in our cohort, but hematologic toxicity was frequent, with severity increasing with higher mean doses delivered to the hematogenous BM and larger volumes of BM receiving 30-35 Gy.

Background: Definitive concurrent chemoradiotherapy (CRT) is the standard of care in advanced stages of head and neck cancer (HNC). With evident increase in survival rate there is also simultaneous increase in toxicity affecting the quality of life. One of the less researched late toxicity is radiation induced brachial plexopathy (RIBP). In this dosimetric study we intent to contour the brachial plexus (BP) as an organ at risk (OAR) and determine the factors that contribute to dose variations to BP, and clinically evaluate the patients for RIBP during follow-up using a questionnaire.

Materials and methods: 30 patients with HNC planned for CRT from September 2020 to June 2022 were accrued. Patients were treated to a dose of 6600 cGy with intensity modulated radiotherapy using the simultaneous integrated boost technique. From the dose-volume histogram (DVH) statistics the BP volume, Dmax and other parameters like V66, V60 were assessed and was correlated with respect to primary tumour and nodal stage.

Results: On corelation, more than the T stage, the N stage and the primary location had a significant impact on the Dmax. With a median follow-up of 17.9 months, the incidence of RIBP was 6.67%. The 2-year disease free survival and the 2-year overall survival were 53.7% and 59.4%, respectively.

Conclusions: In oropharyngeal/hypopharyngeal primaries and in advanced nodal disease, BP receives higher doses contributing to RIBP. Primary tumor and nodal stage also impacted V60 and V66 of BP. Hence, contouring of BP as an OAR becomes imperative, and respecting the DVH parameters is essential.

Background: The behavior of cutaneous squamous cell carcinoma (cSCC) of the head and neck remains poorly understood. There is much controversy regarding the risk of local and nodal recurrences, as well as individual/environmental factors that increase the risk, such as tumor size, perineural invasion, and the state of the immune system. The objective was to analyze factors influencing local and/or regional lymph node recurrence in patients with cSCC in the head and neck region.

Material and methods: This retrospective single-centre study included 521 patients with cSCC of the head and neck region, with local recurrence observed in 11% and nodal recurrence in 5%. Various potential risk factors were analyzed.

Results: Statistically significant risk factors for both local and nodal recurrence include: tumor recurrence (p < 0.0001, p < 0.0001 respectively), tissue inflammation confirmed histopathologically (p < 0.0001, p = 0.0019, respectively), tumor size ≥ 10 mm (p = 0.018, p = 0.0056, respectively), invasion depth > 2 mm (p = 0.0238, p = 0.0031, respectively). Risk factors significant only for local recurrence include: surgical margins (p = 0.0056), tumor differentiation grade (p = 0.0149). No risk factors were found to be significant solely for nodal recurrence.

Conclusion: The authors argue that, in addition to classically recognized risk factors for local and nodal recurrence, attention should be paid to the presence of tissue inflammation confirmed histopathologically. It is also suggested to consider a tumor size of 10 mm as a threshold, increasing the risk of recurrence, instead of the frequently proposed 20 mm.

Background: The purpose of this study was to explore the usage patterns and profiles of social media (SM) platforms among Radiation Oncologists (RO) and Physicists in the scope of the Catalan-Occitan Oncology Group (GOCO).

Materials and methods: From November 2022 to March 2023, a comprehensive survey was sent to Radiation Oncology professionals within the GOCO group, comprising 31 questions that covered demographics (4) and general inquiries (9), user behavior on social media (7), profile of SM activity (7), and participants' opinions (4) regarding professional use of SM. The survey reached professionals from 12 centers, encompassing 10 in Catalonia and 2 in French Occitania.

Results: The survey achieved a 61.37% response rate (178/290 professionals) with an average age of 41.9 years. 120 (67%) were ROs, and 58 (33%) were Physicists. Instagram led in usage (n = 116), followed by Facebook (n = 107) and Twitter (n = 77). Age correlated inversely with the number of platforms used (Spearman's rank correlation coefficient -0.238, p = 0.001). 28% (n = 42) changed clinical practices based on SM information. A 78.5% (n = 117) didn't counter inappropriate content. Most (71.7%, n = 109) spent < 1 hour daily on professional SM use, however more Physicians exceeded 2 hours compared to Physicists (Cohen's kappa 2 = 0.07). 41.8% (n = 64) weren't emotionally concerned while 22.9% (n = 35) felt overwhelmed by SM overload.

Conclusions: The study offers valuable insights into the usage patterns, preferences, and attitudes of Radiation Oncology professionals towards SM platforms. This understanding is crucial for optimizing content quality and delivering relevant information, thereby enabling more effective marketing strategies and enhancing emotional management among these professionals.

Background: The optimal radiotherapy technique for cardiac sparing in left-sided early breast cancer (EBC) is not clear. In this context, the aim of our dosimetric study was to compare cardiac and lung doses according to the type of radiotherapy - whole breast irradiation (WBI), external partial breast irradiation (PBI), and multicatheter interstitial brachytherapy-accelerated partial breast irradiation (MIB-APBI). The dosimetric results with the WBI and PBI were calculated with and without DIBH.

Materials and methods: Dosimetric study of 23 patients treated with WBI, PBI, with and without DIBH, or MIB-APBI. The prescribed dose was 40 Gy in 15 fractions for WBI and PBI and 34 Gy in 10 fractions (bid) for MIB-APBI. Doses to the organs-at-risk (OAR) - heart, left anterior descending coronary artery (LAD), left ventricle (LV), and left lung - were recalculated to the equivalent dose in 2-Gy fractions (EQD2).

Results: The addition of DIBH significantly reduced EQD2 doses to all OARs (except for the left lung maximal dose) in WBI and PBI. MHD values were 0.72 Gy for DIBH-WBI, 1.01 Gy for MIB-APBI and 0.24 Gy for DIBH-PBI. There were no significant differences in cardiac doses between WBI with DIBH and PBI without DIBH. DIBH-PBI resulted in significantly lower mean doses to all OARs (except for maximum lung dose) compared to MIB-APBI. Conclusions: These results show that the use of DIBH significantly reduces cardiac doses in patients with left EBC. Partial irradiation techniques (PBI, MIB-APBI) significantly reduced cardiac doses due to the smaller clinical target volume. The best results were obtained with DIBH-PBI.

Background: The monocyte-to-lymphocyte ratio (MLR), a systemic inflammation biomarker, has been shown to predict patient outcomes in several types of cancer. This study aimed to determine the association between MLR and local control (LC) and cause-specific survival (CSS) rates in patients with non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT).

Materials and methods: The median age of the 194 included participants (144 men, 50 women) was 80 (range, 50-96) years. The median follow-up period was 19 (range, 1-108) months. The LC and CSS rates were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazard regression models were used to estimate the LC and CSS rates.

Results: Local recurrence was observed in 25 patients during the follow-up. Univariate Cox proportional hazards regression analysis revealed that MLR, performance status, and tumor diameter were significant factors for LC. Multivariate analysis showed MLR and tumor diameter as significant factors (p = 0.041 and 0.031, respectively). The 1- and 2-year LC rates for the lower and higher MLR groups were 97.5% and 97.5%, and 89.7% and 81.2%, respectively. During the follow-up period, 14 patients died due to NSCLC. Although MLR tended to predict CSS in univariate analysis (p = 0.086), none of the parameters was significant in predicting CSS. However, MLR as a continuous variable was a significant factor for CSS in the univariate analysis (p = 0.004).

Conclusions: Our data suggest that MLR is correlated with LC and CSS rates in NSCLC patients treated with SBRT.

Background: Attainment of a complete histopathological response following neoadjuvant therapy has been associated with favorable long-term survival outcomes in esophageal cancer patients. We investigated the ability of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) radiomic features to predict the pathological response to neoadjuvant treatment in patients with esophageal cancer.

Materials and methods: A retrospective review of medical records of patients with locally advanced resectable esophageal or esophagogastric junctional cancers. Included patients had a baseline FDG PET/CT scan and underwent Chemoradiotherapy for Oesophageal Cancer Followed by Surgery Study (CROSS) protocol followed by surgery. Four demographic variables and 107 PET radiomic features were extracted and analyzed using univariate and multivariate analyses to predict response to neoadjuvant therapy.

Results: Overall, 53 FDG-avid primary esophageal cancer lesions were segmented and radiomic features were extracted. Seventeen radiomic features and 2 non-radiomics variables were found to exhibit significant differences between neoadjuvant therapy responders and non-responders. An unsupervised hierarchical clustering analysis using these 19 variables classified patients in a manner significantly associated with response to neoadjuvant treatment (p < 0.01).

Conclusion: Our findings highlight the potential of FDG PET/CT radiomic features as a predictor for the response to neoadjuvant therapy in esophageal cancer patients. The combination of these radiomic features with select non-radiomic variables provides a model for stratifying patients based on their likelihood to respond to neoadjuvant treatment.

Background: Facemasks accurately immobilise patients with head and neck cancer (HNC) receiving radiotherapy (RT). However, such masks are associated with treatment related distress, a prognostic factor for poorer survival. Open masks offer increased comfort and patient satisfaction. We investigated whether open masks could immobilise patients without affecting treatment accuracy.

Materials and methods: Over an 18-month period, all HNC RT patients with anxiety were offered open masks. Once 30 patients had completed treatment, set-up data was compared to patients in closed masks. The mean displacement and one-dimensional standard deviations (SD) of the mean, systematic and random set-up errors were calculated for translational directions: anterior-posterior (x), superior-inferior (y), medial-lateral (z). The mean and SD of the mean was calculated for rotational displacements. Mann-Whitney U was used to determine any significant differences between set-up data.

Results: Sixty patients were included (30 open & 30 closed masks). There was no statistically significant difference found in the x (p = 0.701), y (p = 0.246) or z (p = 0.535) direction for the SD of the mean displacements between both masks. No statistically significant difference was found in the SD of means for rotational displacements. The calculated planning target volume (PTV) margin requirements were minimally less for the closed masks 3.5, 2.6, and 2.7 mm (x, y, z, respectively) versus 4.2, 3.2, and 3.7 mm, respectively, for open masks.

Conclusion: Our study demonstrates that open masks maintain accuracy at levels comparable to closed masks in patients with anxiety. The minor difference in the calculated PTV margin could be rectified with daily on-line imaging or surface guided imaging.