Emerging data suggest that higher radiation doses in post-mastectomy radiotherapy may be associated with an increased risk of reconstruction complications. This study aimed to validate previous findings regarding the impact of radiation dose on complications among women with breast cancer using a multi-center dataset. Fifteen institutions participated, and women with breast cancer who received radiotherapy after either autologous or prosthetic breast reconstruction were included. The primary endpoint was major post-radiation therapy complications requiring re-operation for explantation, flap failure, or bleeding control. In total, 314 patients were included. Radiotherapy was performed using both conventional fractionation and hypofractionation in various schedules. The range of the radiation therapy dose in Equivalent Dose in 2 Gy fractions (EQD2; α/β = 3.5) varied from 43.4 to 71.0 Gy (median dose: 48.6 Gy). Boost radiation therapy was administered to 49 patients. Major post-radiation therapy complications were observed in 24 (7.6%) patients. In multivariate analysis, an increasing EQD2 per Gy (odds ratio [OR]: 1.58, 95% confidence interval [CI]: 1.26-1.98; p < 0.001), current smoking status (OR: 25.48, 95% CI: 1.56-415.65; p = 0.023), and prosthetic breast reconstruction (OR: 9.28, 95% CI: 1.84-46.70; p = 0.007) were independently associated with an increased risk of major complications. A dose-response relationship between radiation dose and the risk of complications was validated in this multi-center dataset. In this context, we hypothesize that the use of hypofractionated radiotherapy (40 Gy in 15 fractions) may improve breast reconstruction outcomes. Our multi-center prospective observational study (NCT03523078) is underway to further validate this hypothesis.

This study aimed for a collaborative evaluation of variability in the target volumes for glioblastoma, determined and contoured by different radiotherapy (RT) facilities in Korea. Fifteen panels of radiation oncologists from independent institutions contoured the gross target volumes (GTVs) and clinical target volumes (CTVs) for 3-dimensional conformal RT or intensity-modulated RT on each simulation CT images, after scrutinizing the enhanced T1-weighted and T2-weighted-fluid-attenuated inversion recovery MR images of 9 different cases of glioblastoma. Degrees of contouring agreement were analyzed by the kappa statistics. Using the algorithm of simultaneous truth and performance level estimation (STAPLE), GTVSTAPLE and CTVSTAPLE contours were derived. Contour agreement was moderate (mean kappa 0.58) among the GTVs and was substantial (mean kappa 0.65) among the CTVs. However, each panels’ GTVs and modification of CTVs regarding anatomical structures varied. Three-fourth of contoured panels’ CTVs encompassed the peritumoral areas of T2-high signal intensity (T2-HSI). Nine of nine GTVSTAPLE encompased the surgical cavity and the T1-enhanced lesions. Eight of nine CTVSTAPLE encompassed the peritumoral T2-HSI area. The median MARGIN90 and the median MARGIN95 were 1.4 cm and 1.5 cm, respectively. Moderate to substantial agreement existed in target volumes for 3-dimensional or intensity-modulated RT determined by radiation oncologists in Korea. According to the estimated consensus contours, the initial CTV encompassed the GTV with margin less than 2.0 cm and the whole peritumoral areas of T2-HSI. The findings of our study propose the need for further studies and modified guidelines.

Background: The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) as a boost treatment for head and neck cancer. Materials and methods: Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were initially treated with standard external beam radiotherapy (EBRT). SBRT boost was prescribed to the median 80% isodose line with a median dose of 21 (range 10–25) Gy in 2–5 (median, 5) fractions. Results: The median follow-up after SBRT was 56 (range 27.6 − 80.2) months. The distribution of treatment sites in 26 patients was as follows: the nasopharynx, including the base of the skull in 10 (38.5%); nasal cavity or paranasal sinus in 8 (30.8%); periorbit in 4 (15.4%); tongue in 3 (11.5%); and oropharyngeal wall in 1 (3.8%). The median EBRT dose before SBRT was 50.4 Gy (range 39.6 − 70.2). The major response rate was 100% with 21 (80.8%) complete responses (CR). Severe (grade ≥ 3) late toxicities developed in 9 (34.6%) patients, and SBRT boost volume was a significant parameter predicting severe late complication. Conclusions: The present study demonstrates that a modern SBRT boost is a highly efficient tool for local tumor control. However, we observed a high frequency of serious late complications. More optimized dose fractionation schedule and patient selection are required to achieve excellent local control without significant late morbidities in head and neck boost treatment.

Radiation therapy (RT) continues to be the primary approach for treating cancer, and numerous cancer biomarkers associated with oncological outcomes have been investigated in the context of RT. The serum platelet-to-lymphocyte ratio (PLR) is one of the emerging landmark biomarker in the oncologic field. Mounting evidence indicates that an elevated serum PLR may function as a marker of unfavorable tumor characteristics, adverse treatment outcomes and treatment-related toxicities among individuals undergoing RT. However, the findings of these investigations have revealed a few disparities among researchers, highlighting the need for further meticulously planned studies to draw conclusive results. This article provides a comprehensive literature review and in-depth discussion regarding the clinical implications of the serum PLR in the modern RT era.

This study was aimed to assess the outcome of radiotherapy and determine prognostic factors for survival in breast cancer patients with clinically overt metastasis to the internal mammary lymph node (IMN+). We retrospectively reviewed the medical records of 193 patients with IMN + breast cancer who received neoadjuvant chemotherapy (NAC), breast surgery without internal mammary lymph node (IMN) dissection, and postoperative radiotherapy at 9 hospitals between 2009 and 2013. Breast-conserving surgery or mastectomy was performed after taxane-based NAC. Radiotherapy was administered to the whole breast/chest wall and regional nodes. IMN-covering radiotherapy was performed in 92.2% of patients with median dose of 58.4 Gy (range, 44.9-69.1 Gy). The overall survival (OS), disease-free survival (DFS), and IMN failure-free survival (IMNFFS) were analyzed. After median follow-up of 71 months, 9 patients (4.7%) developed IMN failure and simultaneous distant metastasis. The 5-year DFS, OS, and IMNFFS was 68.6%, 81.8%, and 95.3%, respectively. Non-triple-negative breast cancer, Ki-67 ≤ 10%, pathological complete response (CR) in tumor and axillary node, and radiologic CR of IMN after NAC were significant factors for predicting higher DFS; however, IMN radiation dose was not significant determinants for DFS. The 5-year DFS of patients with IMN-dose ≤ 50.0 Gy and those with >50.0 Gy was 86.7% and 76.7%, respectively (p = 0.41). A multimodality strategy including NAC, breast surgery, and IMN-covering radiotherapy was effective for patients with overt IMN + breast cancer. Even without an IMN dissection, most patients were IMN failure-free with an IMN-focusing radiotherapy.