UNASSIGNED: The local management approach for node-positive breast cancer has undergone substantial evolution. Consequently, there exists a pressing need to enhance our treatment strategies by placing greater emphasis on planning and dosimetric factors, given the availability of more conformal techniques and delineation criteria, achieving optimal goals of radiotherapy treatment. The primary aim of this article is to discuss how the extent of regional nodal coverage influences the choice between IMRT and 3D radiation therapy for patients.
UNASSIGNED: A total of 15 patients diagnosed with left breast cancer with disease involved lymph nodes were included in this study. Delivering the recommended dose required the use of a linear accelerator (LINAC) with photon beams energy of 6 mega voltage (6MV). Each patient had full breast radiation using two planning procedures: intensity-modulated radiotherapy (IMRT) and three-dimensional radiotherapy (3D conformal). Following the guidelines set forth by the Radiation Therapy Oncology Group (RTOG), the planned treatment coverage was carefully designed to fall between 95% and 107% of the recommended dose. Additionally, Dose Volume Histograms (DVHs) were generated the dose distribution within these anatomical contours.
UNASSIGNED: The DVH parameters were subjected to a comparative analysis, focusing on the doses absorbed by both Organs at Risk (OARs) and the Planning Target Volume (PTV). The findings suggest that low doses in IMRT plan might raise the risk of adverse oncological outcomes or potentially result in an increased incidence of subsequent malignancies. Consequently, the adoption of inverse IMRT remains limited, and the decision to opt for this therapy should be reserved for situations where it is genuinely necessary to uphold a satisfactory quality of life. Additionally, this approach helps in reducing the likelihood of developing thyroid problems and mitigates the risk of injuries to the supraclavicular area and the proximal head of the humerus bone.

OBJECTIVE: Patients with recurrent squamous cell carcinoma of the head and neck (HNSCC) have a poor prognosis and limited therapeutic alternatives. While reirradiation is feasible, it is usually associated with high treatment toxicity and is not yet considered the standard of care. Based on current NCCN guidelines, in the context of very advanced head and neck cancer (recurrent and/or persistent disease), surgical intervention is explored initially with/without adjuvants while unresectable disease is approached with radiation and/or systemic therapies. Specific and reliable prognostic indicators for both -oncologic and functional outcomes- have yet to be defined for this population.
METHODS: Retrospective chart review of 54 patients treated with reirradiation at a tertiary academic institution between January of 1998 and January of 2024. Only patients with non-metastatic recurrent, and second primary HNSCC were included in the series. Demographics, staging, radiation dose and technique, additional therapy, histopathologic variables, EORTC toxicity, pre- and post-treatment PEG/tracheotomy dependency and oncologic outcomes were retrieved.
RESULTS: The study cohort consisted of 54 patients (37 males, 17 females) with HNSCC, averaging 62.7 years in age. Initial tumors were locally advanced in over 42 % of cases, with 58 % being node-negative. The head and cutaneous regions (24.5 %) and tongue (20.8 %) were the most common tumor sites. Primary surgical resection and adjuvant radiation were performed in 47.2 % of cases, and concurrent chemotherapy was used in 40.7 %. Reirradiation was mainly for local or regional recurrence (88.9 %), often following salvage surgery (68.5 %), with a mean dose of 5623 Gy over 52.5 fractions. Positive surgical margins were present in 29.4 % of cases, and extracapsular spread in 59.5 %. No significant differences were found between the salvage surgery and definitive reirradiation groups except for tumor site (P = 0.022). Median follow-up was 52.6 months, with 27 deaths reported. Lymphovascular invasion was significantly correlated with overall survival (P = 0.017), while initial tumor T-stage and neck disease involvement were linked to local-regional control (P = 0.030 and P = 0.033, respectively). Reirradiation increased tracheotomy and PEG-tube dependency by 20 % (P = 0.011) and 23 % (P = 0.003), respectively.
CONCLUSIONS: Reirradiation is a feasible therapeutic alternative in recurrent head and neck SCC. Oncologic outcomes observed in this series compare favorably to most published reports. Complete response and perineural invasion were independent prognostic factors for survival and locoregional control. While no mortality directly associated with treatment was observed in this series, reirradiation had a significant impact in functional outcomes in terms of increased risk of tracheotomy and peg tube dependency. Further studies are required to define the role of this treatment in head and neck cancer.

OBJECTIVE: To compare the dosimetric parameters considering the Radiation Therapy Oncology Group (RTOG) and European Society for Radiotherapy and Oncology (ESTRO) guidelines for breast cancer radiotherapy. Two radiotherapy techniques, intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT), were considered.
METHODS: Twenty-eight patients with left-sided medially-located TanyN2M0 tumors were contoured based on RTOG and ESTRO guidelines. 9-field IMRT, 10-field IMRT, 11-field IMRT, and VMAT treatment plans were applied as radiotherapy (RT) techniques for both contouring sets. The dosimetric parameters of the RT plans were extracted and compared.
RESULTS: Comparing dose-volume histogram (DVH) parameters, equivalent uniform dose (EUD), and normal tissue complication probability (NTCP) of OARs across the contouring guidelines and considering each RT technique showed that the only significant differences were higher Dmax, Dmean, V30, and V45, EUD, and NTCP of the thyroid in all treatment modalities when the RTOG guideline had been adopted. Using the VMAT technique, PTV\'s EUD and the tumor control probability (TCP) were considerably higher when the ESTRO guideline was adopted. Moreover, the conformity index (CI) of VMAT plans was significantly higher when the ESTRO guideline was used.
CONCLUSIONS: Unless having higher doses to thyroid when the RTOG guideline was adopted, the doses to other organs-at-risk (OAR) were similar between the two considering guidelines. Moreover, except for higher EUD, TCP, and CI for VMAT when the ESTRO guideline was used, no other significant differences were obtained between dosimetric parameters of target volumes considering the RT techniques and contouring guidelines.

OBJECTIVE: This was a double-blind, placebo-controlled randomized study investigating whether melatonin can protect against radiation dermatitis in women receiving radiation therapy for primary breast cancer.
METHODS: Patients were included before radiation therapy and followed once weekly throughout treatment with a 3-week follow-up. Patients applied 1 g of cream to the irradiated skin twice daily, consisting of either 25 mg/g melatonin and 150 mg/g dimethyl sulfoxide, or placebo. Our outcomes were the Radiation Therapy Oncology Group\'s (RTOG) acute radiation morbidity scoring criteria for skin, a pixel analysis of erythema in clinical photographs, and patients\' use of corticosteroid cream. Outcomes were evaluated once weekly throughout the trial. The primary outcomes were RTOG-score and pixel analysis at 2 weeks follow-up. Secondary outcomes were the use of corticosteroid cream and analyses of RTOG-scores and pixel analyses throughout the trial.
RESULTS: Sixty-five patients were included, 17 dropped out, totaling 26 and 22 patients randomized to melatonin and placebo, respectively. RTOG-scores and pixel analyses at 2 weeks follow-up showed no difference p = .441 and p = .890, respectively). There was no difference in the use of corticosteroid cream (p = .055). Using logistic regression, the melatonin group had a higher likelihood of having a low RTOG-score (p = .0016). The logistic regression showed no difference between the groups for the pixel analyses.
CONCLUSIONS: Our primary outcome showed no difference in RTOG-scores at 2 weeks follow-up, however, the RTOG-score over the entire duration of the study demonstrated a protective effect of melatonin. Further studies are warranted investigating higher doses of melatonin, and whether corticosteroids may influence the effect of melatonin cream against radiation dermatitis.

The aim of this study was to analyze the patterns of prostate bed (PB) recurrence in prostate cancer patients experiencing prostate-specific antigen (PSA) persistence (BCP) or biochemical recurrence (BCR) after radical prostatectomy using 68Ga-PSMA-11 PET/CT (68Ga-PSMA PET) in relation to the Radiation Therapy Oncology Group (RTOG) clinical target volumes (CTVs). Methods: This single-center, retrospective analysis included patients with BCP or BCR after radical prostatectomy and PB recurrence on 68Ga-PSMA PET. The PB recurrences were delineated by nuclear medicine physicians, the CTVs by radiation oncologists contouring guidelines on the 68Ga-PSMA PET, respectively, masked from each other. The coverage of the 68Ga-PSMA PET recurrence was categorized as PSMA recurrence completely covered, partially covered, or not covered by the RTOG-based CTV. Further, we evaluated the differences in PSMA recurrence patterns among patients with different 68Ga-PSMA PET staging (miTNM). Mann-Whitney U tests, the chi-square test, and Spearman (ρ) correlation analysis were used to investigate associations between CTV coverage and 68Ga-PSMA PET-based tumor volume, serum PSA levels, miTNM, and rectal/bladder involvement. Results: A total of 226 patients were included in the analysis; 127 patients had PSMA recurrence limited to the PB (miTrN0M0), 30 had pelvic nodal disease (miTrN1M0), 32 had extrapelvic disease (miTrN0M1), and 37 had both pelvic nodal disease and extrapelvic disease (miTrN1M1). In the miTrN0M0 cohort, the recurrence involved the rectal and bladder walls in 12 of 127 (9%) and 4 of 127 (3%), respectively. The PSMA-positive PB recurrences were completely covered by the CTV in 68 of 127 patients (53%), partially covered in 43 of 127 (34%), and not covered in 16 of 127 (13%). Full coverage was associated with a smaller tumor volume (P = 0.043), a lack of rectal/bladder wall involvement (P = 0.03), and lower miTNM staging (P = 0.035) but not with lower serum PSA levels (P = 0.979). Conclusion: Our study suggests that 68Ga-PSMA PET can be a valuable tool for guiding salvage radiation therapy (SRT) planning directed to the PB in the setting of postoperative BCR or BCP. These data should be incorporated into the redefinition of PB contouring guidelines.

Oligodendrogliomas are a subtype of adult diffuse glioma characterized by their better responsiveness to systemic chemotherapy than other high-grade glial tumors. The World Health Organization (WHO) 2021 brain tumor classification highlighted defining molecular markers, including 1p19q codeletion and IDH mutations which have become key in diagnosing and treating oligodendrogliomas. The management for patients with oligodendrogliomas includes observation or surgical resection potentially followed by radiation and chemotherapy with PCV (Procarbazine, Lomustine, and Vincristine) or Temozolomide. However, most of the available research about oligodendrogliomas includes a mix of histologically and molecularly diagnosed tumors. Even data driving our current management guidelines are based on post-hoc subgroup analyses of the 1p19q codeleted population in landmark prospective trials. Therefore, the optimal treatment paradigm for molecularly defined oligodendrogliomas is incompletely understood. Many questions remain open, such as the optimal timing of radiation and chemotherapy, the response to different chemotherapeutic agents, or what genetic factors influence responsiveness to these agents. Ultimately, oligodendrogliomas are still incurable and new therapies, such as targeting IDH mutations, are necessary. In this opinion piece, we present relevant literature in the field, discuss current challenges, and propose some studies that we think are necessary to answer these critical questions.

BACKGROUND: We previously showed that Mepitel Film decreased the severity of acute radiation-induced skin reactions in head and neck cancer patients. In the current study, we compared the effect of Mepitel Film and Biafine cream on skin reaction severity in a larger cohort of head and neck cancer patients.
METHODS: A total of 44 head and neck cancer patients were recruited with 39 patients contributing full data sets for analysis. Patients received a dose of 50 Gy in 25 fractions to the bilateral lymph nodes in the neck. Left and right lymph node areas were randomised to either Mepitel Film or Biafine cream, applied prophylactically. Skin reaction severity was measured using Radiation-Induced Skin Reaction Assessment Scale (RISRAS) and expanded Radiation Oncology group (RTOG) grades. Skin dose was measured using gafchromic Film.
RESULTS: Skin reaction severity (combined RISRAS score) underneath Mepitel Film was decreased by 30% (P < 0.001) and moist desquamation rates by 41% (P < 0.001). Skin dose underneath Mepitel Film and Biafine cream was similar (P = 0.925) and unlikely to have affected skin reaction severity. The vast majority (80%) of patients preferred Mepitel Film over Biafine cream. Negative aspects of Mepitel Film included poor adherence (11/39) and discomfort (16/39) during hot weather and showering and itchy skin underneath Mepitel Film (12/39).
CONCLUSIONS: Mepitel Film was superior to Biafine cream in reducing the severity of acute radiation-induced skin reactions and moist desquamation incidence in our head and neck patient cohort.

Aim: European Organization for Research and Treatment of Cancer (EORTC) and the Radiation Therapy Oncology Group (RTOG) criteria are used to choose treatment in low-grade gliomas. However, no data exist on their concordance. Methods: Low-grade glioma patients treated at our institution from 1998 to 2015 and assessable for both RTOG and EORTC criteria were included to analyze their concordance. Surgery extension, postsurgical treatments, molecular characteristics (IDH mutation, MGMT methylation and 1p/19q codeletion) were recorded. Results: We included 99 patients. The concordance was low (50.5%; K = 0.127; p = 0.021) but for two subgroups: EORTC high-risk patients were also RTOG high-risk patients (concordance: 97.5%) and RTOG low-risk patients were also EORTC low-risk patients (concordance: 90.9%). Conclusion: The concordance between RTOG and EORTC criteria is low. Thus, clinical trials adopting different risk criteria are not comparable.

UNASSIGNED: To investigate the feasibility of including patients\' reports on the cosmetic properties of topical formulations for acute radiation dermatitis (ARD).
UNASSIGNED: No topical agent tested for acute radiation dermatitis (ARD) has proven to be better than any other, all achieving similar objective outcomes. No clear guidelines have therefore been established in clinics. Because the vehicle for such creams has shown to be an important factor in patient adherence to treatments in other dermatological diseases, patients\' opinions are evaluated.
UNASSIGNED: Seventy breast cancer patients referred for postoperative radiotherapy after conservative surgery were enrolled. Patients were assigned to use one of the 7 topical agents that are most-commonly used in the prevention of ARD. Patients\' reports were assessed using continuous visual analogue scales (VAS), objective signs and symptoms produced by ARD, and were rated using the RTOG and RISRAS scales.
UNASSIGNED: The creams tested differed in their cosmetic properties significantly (p = 0.044). The performance of the agent, their absorption and any residue left over were also significantly different (p = 0.022, 0.014 and 0.02, respectively).
UNASSIGNED: Topical agents for preventive ARD are reported by patients to show different cosmetic properties. Cosmetic properties are important when choosing topical agents for ARD prevention. Recommending those with better cosmetic profiles would improve patient adherence to treatments.

Linear scaling is used to convert raw computed tomography (CT) pixel values into Hounsfield units corresponding to different tissue values. Analysis of a benchmarking study, presented here, where the same CT scan was imported into and then exported from multiple radiotherapy treatment planning systems, found inconsistencies in HU scaling parameter values exported along with the images, particularly when images were exported using the Radiation Therapy Oncology Group format. Several methods of estimating conversion parameters, based on estimating pixel values corresponding to air and water within the image, for pelvic CT images from a large multi-centre trial were compared against original Digital Imaging and Communications in Medicine export parameters. In general using the mean of a sample region at the centroid of the bladder to estimate the value of water was more accurate than using the minimum or maximum or a single value at the centroid. Accuracy of methods of air estimation tested were dependent in part on features of the CT scanners and treatment planning systems, making it difficult to pick one method as superior that was independent of scanner and treatment planning system type. Based on the above analysis, methods for estimating air and water were selected for use in performing linear scaling of a set of pelvic CT images prior to their use in an interpatient image registration application. The selected methods were validated against a more recent and homogeneous dataset. Estimation error was found to be much lower within the validation set.