Clinical Use of a Commercial Artificial Intelligence-Based Software for Autocontouring in Radiation Therapy: Geometric Performance and Dosimetric Impact.

PURPOSE: When autocontouring based on artificial intelligence (AI) is used in the radiotherapy (RT) workflow, the contours are reviewed and eventually adjusted by a radiation oncologist before an RT treatment plan is generated, with the purpose of improving dosimetry and reducing both interobserver variability and time for contouring. The purpose of this study was to evaluate the results of application of a commercial AI-based autocontouring for RT, assessing both geometric accuracies and the influence on optimized dose from automatically generated contours after review by human operator. MATERIALS AND METHODS: A commercial autocontouring system was applied to a retrospective database of 40 patients, of which 20 were treated with radiotherapy for prostate cancer (PCa) and 20 for head and neck cancer (HNC). Contours resulting from AI were compared against AI contours reviewed by human operator and human-only contours using Dice similarity coefficient (DSC), Hausdorff distance (HD), and relative volume difference (RVD). Dosimetric indices such as Dmean, D0.03cc, and normalized plan quality metrics were used to compare dose distributions from RT plans generated from structure sets contoured by humans assisted by AI against plans from manual contours. The reduction in contouring time obtained by using automated tools was also assessed. A Wilcoxon rank sum test was computed to assess the significance of differences. Interobserver variability of the comparison of manual vs. AI-assisted contours was also assessed among two radiation oncologists for PCa. RESULTS: For PCa, AI-assisted segmentation showed good agreement with expert radiation oncologist structures with average DSC among patients ≥ 0.7 for all structures, and minimal radiation oncology adjustment of structures (DSC of adjusted versus AI structures ≥ 0.91). For HNC, results of comparison between manual and AI contouring varied considerably e.g., 0.77 for oral cavity and 0.11-0.13 for brachial plexus, but again, adjustment was generally minimal (DSC of adjusted against AI contours 0.97 for oral cavity, 0.92-0.93 for brachial plexus). The difference in dose for the target and organs at risk were not statistically significant between human and AI-assisted, with the only exceptions of D0.03cc to the anal canal and Dmean to the brachial plexus. The observed average differences in plan quality for PCa and HNC cases were 8% and 6.7%, respectively. The dose parameter changes due to interobserver variability in PCa were small, with the exception of the anal canal, where large dose variations were observed. The reduction in time required for contouring was 72% for PCa and 84% for HNC. CONCLUSIONS: When an autocontouring system is used in combination with human review, the time of the RT workflow is significantly reduced without affecting dose distribution and plan quality.

Radiation recall dermatitis induced by COVID-19 vaccination in breast cancer patients treated with postoperative radiation therapy.

BACKGROUND: and purpose: Radiation recall dermatitis is an adverse event predominantly due to systemic therapy administration after a previous radiation therapy course. Few case reports describe radiation recall dermatitis in breast cancer patients treated with postoperative radiation therapy following COVID-19 vaccination. In this study we investigated the incidence and severity of radiation recall dermatitis after COVID-19 vaccination in irradiated breast cancer patients. METHODS: Patients that received at least one COVID-19 vaccination dose during the year after the end of postoperative breast radiation therapy were included in this observational monocentric study. Local symptoms occurring inside the radiation field after vaccination were patient-reported and scored according to the PRO-CTCAE questionnaire. Descriptive data of radiation recall dermatitis incidence and severity, and potential risk factors were evaluated. RESULTS: A cohort of 361 patients with 756 administered COVID-19 vaccinations was analyzed. Breast symptoms were reported by 7.5% of patients, while radiation recall dermatitis was considered for 5.5%. The incidence of radiation recall dermatitis per single dose of vaccine was 2.6%, with a higher risk for the first dose compared to the second/third (4.4% vs 1%, p = 0.003), especially when administered within the first month after the end of irradiation (12.5% vs 2.2%, p = 0.0004). Local symptoms were generally self-limited and a few cases required anti-inflammatory drugs. CONCLUSIONS: Radiation recall dermatitis is an uncommon but not rare phenomenon in breast cancer patients that received COVID-19 vaccination within one year after breast irradiation. However, symptoms severity were generally low/mild and reversible. These findings can be useful for patient counseling.

Female breast cancer in sub-Saharan Africa: A PRISMA-S-compliant systematic review of surgery.

BACKGROUND: In sub-Saharan countries (SSAs), the advanced stage at diagnosis and the limited surgical interventions of female breast cancer (FBC) lead to poor outcomes. This study assessed current modalities of FBC surgeries. METHODS: Six literature databases (Medline, Embase, African Journal Online, Google Scholar, Web of Science, Cochrane Library) were searched, plus a manual search, in 2011-2021. We included primary data studies with any setting and presurgeries or postsurgeries treatments, we excluded non-English language studies, editorials, and grey literature. RESULTS: The search yielded 21 observational studies (16 retrospective, 3 prospective, and 2 case reports). Of the total 6900 patients, 4121 (60%) patients underwent FBC surgical excision only, and 751/2779 (27%) conservative surgery (BCS) or therapy (BCT). All studies reported similar use of mastectomy (>60%), the FBC surgical excision/reconstruction studies displayed more neoadjuvant chemotherapy (536/2779, 19% vs. 215/4121, 5%), and radiotherapy or adjuvant radiotherapy (1461/2779, 52% vs. 411/3921, 4%). Patients' age, histological classification, staging, and follow-up data were often missing. CONCLUSIONS: The FBC complexity requires structured management by general and plastic surgeons, radiotherapy specialists, and obstetrician-gynecologists through shared guidelines, protocols, and specific programs of public health. In SSAs, FBC surgical strategies should point at decreasing radical mastectomy and increasing BCS/BCT.

Prognostic Nutritional Index Predicts Toxicity in Head and Neck Cancer Patients Treated with Definitive Radiotherapy in Association with Chemotherapy.

BACKGROUND: The Prognostic Nutritional Index (PNI) is a parameter of nutritional and inflammation status related to toxicity in cancer treatment. Since data for head and neck cancer are scanty, this study aims to investigate the association between PNI and acute and late toxicity for this malignancy. METHODS: A retrospective cohort of 179 head and neck cancer patients treated with definitive radiotherapy with induction/concurrent chemotherapy was followed-up (median follow-up: 38 months) for toxicity and vital status between 2010 and 2017. PNI was calculated according to Onodera formula and low/high PNI levels were defined according to median value. Odds ratio (OR) for acute toxicity were calculated through logistic regression model; hazard ratios (HR) for late toxicity and survival were calculated through the Cox proportional hazards model. RESULTS: median PNI was 50.0 (interquartile range: 45.5-53.5). Low PNI was associated with higher risk of weight loss > 10% during treatment (OR = 4.84, 95% CI: 1.73-13.53 for PNI < 50 versus PNI ≥ 50), which was in turn significantly associated with worse overall survival, and higher risk of late mucositis (HR = 1.84; 95% CI:1.09-3.12). PNI predicts acute weight loss >10% and late mucositis. CONCLUSIONS: PNI could help clinicians to identify patients undergoing radiotherapy who are at high risk of acute and late toxicity.

Electron Density and Biologically Effective Dose (BED) Radiomics-Based Machine Learning Models to Predict Late Radiation-Induced Subcutaneous Fibrosis.

Purpose: to predict the occurrence of late subcutaneous radiation induced fibrosis (RIF) after partial breast irradiation (PBI) for breast carcinoma by using machine learning (ML) models and radiomic features from 3D Biologically Effective Dose (3D-BED) and Relative Electron Density (3D-RED). Methods: 165 patients underwent external PBI following a hypo-fractionation protocol consisting of 40 Gy/10 fractions, 35 Gy/7 fractions, and 28 Gy/4 fractions, for 73, 60, and 32 patients, respectively. Physicians evaluated toxicity at regular intervals by the Common Terminology Adverse Events (CTAE) version 4.0. RIF was assessed every 3 months after the completion of radiation course and scored prospectively. RIF was experienced by 41 (24.8%) patients after average 5 years of follow up. The Hounsfield Units (HU) of the CT-images were converted into relative electron density (3D-RED) and Dose maps into Biologically Effective Dose (3D-BED), respectively. Shape, first-order and textural features of 3D-RED and 3D-BED were calculated in the planning target volume (PTV) and breast. Clinical and demographic variables were also considered (954 features in total). Imbalance of the dataset was addressed by data augmentation using ADASYN technique. A subset of non-redundant features that best predict the data was identified by sequential feature selection. Support Vector Machines (SVM), ensemble machine learning (EML) using various aggregation algorithms and Naive Bayes (NB) classifiers were trained on patient dataset to predict RIF occurrence. Models were assessed using sensitivity and specificity of the ML classifiers and the area under the receiver operator characteristic curve (AUC) of the score functions in repeated 5-fold cross validation on the augmented dataset. Results: The SVM model with seven features was preferred for RIF prediction and scored sensitivity 0.83 (95% CI 0.80-0.86), specificity 0.75 (95% CI 0.71-0.77) and AUC of the score function 0.86 (0.85-0.88) on cross-validation. The selected features included cluster shade and Run Length Non-uniformity of breast 3D-BED, kurtosis and cluster shade from PTV 3D-RED, and 10th percentile of PTV 3D-BED. Conclusion: Textures extracted from 3D-BED and 3D-RED in the breast and PTV can predict late RIF and may help better select patient candidates to exclusive PBI.

Prognostic significance of neutrophil-to-lymphocyte ratio in HPV status era for oropharyngeal cancer.

AIM: To evaluate the role of baseline neutrophil-to-lymphocyte ratio (NLR) as prognostic marker in squamous cell carcinoma of the oropharynx (OPC) treated with definitive chemoradiotherapy (CRT) in the era of HPV status. PATIENTS AND METHODS: A retrospective analysis of 125 patients (pts) affected with locally advanced OPC was performed. Inclusion criteria were age >18 years, stage III or IV (TNM 7th ed.) and definitive CRT. Haematological marker for their independent role as prognostic biomarkers for progression-free survival (PFS) and overall survival (OS). Logistic models were used to assess the association with downstage in TNM 8th ed. RESULTS: Seventy-seven (61.6%) pts had HPV/p16 + related OPC. Therapeutic choice consisted in sequential and concurrent CRT. Median follow-up was 50 months. A value of NLR ≥3 was associated with poorer OS. Two-year OS was 91% and 81% in pts with NLR <3 and ≥3, respectively. CONCLUSION: A baseline NLR ≥ 3 at treatment initiation represented a negative prognostic marker for OPC treated with definitive CRT. These results are in line with literature data, and prognostic value of NLR has been confirmed restaging our cohort with new TNM staging (8th ed.). Therefore, NLR could be considered a valuable biomarker for risk stratification in pts with OPC.

Does baseline [18F] FDG-PET/CT correlate with tumor staging, response after neoadjuvant chemoradiotherapy, and prognosis in patients with rectal cancer?

BACKGROUND: [18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F] FDG-PET/CT) may be used for tumor staging and prognosis in several tumors but its role in rectal cancer is still debated. The aim of the present study was to assess the correlation of baseline [18F] FDG-PET parameters with tumor staging, tumor response (tumor regression grade (TRG)), and outcome in a series of patients affected by locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (CRT). METHODS: One hundred patients treated with neoadjuvant CRT and radical surgery were enrolled in the present study. Maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) at the baseline [18F] FDG-PET were calculated. These PET parameters were correlated with tumor staging, histopathological data (TRG1 vs. TRG2-5 and TRG1-2 vs. TRG3-5), disease-free survival, and overall survival. RESULTS: SUVmax and SUVmean of primary tumor were statistically associated with T4-stage. SUVmax, SUVmean, and TLG did not result statistically associated with TRG (TRG1 or TRG1-2). MTV resulted statistically associated with TRG1-2 group (OR 2.9; 95% CI 1.2-7.1). Finally, no PET parameter was significantly associated with disease-free or overall survival. CONCLUSION: Our results showed that baseline [18F] FDG-PET parameters correlated with tumor staging, and only MTV correlated with TRG 1-2. PET parameters failed to predict disease-free and overall survival after treatment completion. The results leave open to further studies the issue of identifying patients suitable for conservative approaches.

Time to surgery and pathologic complete response after neoadjuvant chemoradiation in rectal cancer: A population study on 2094 patients.

BACKGROUND: To retrospectively evaluate the difference in terms of pathologic complete response (pCR) according to time elapsed between chemoradiation (CRT) and total mesorectal excision (TME) on a large unselected real-life dataset of locally advanced rectal cancer (LARC) patients. METHODS: A multicentre retrospective cohort study of LARC patients from 21 Italian Radiotherapy Institutions was performed. Patients were stratified into 3 different time intervals from CRT. The 1st group included 300 patients who underwent TME within 6 weeks, the 2nd 1598 patients (TME within 7-12 weeks) and the 3rd 196 patients (TME within 13 or more weeks after CRT), respectively. RESULTS: Data on 2094 LARC patients treated between 1997 and 2016 were considered suitable for analysis. Overall, 578 patients had stage II while 1516 had stage III histological proven invasive rectal adenocarcinoma. A CRT schedule of one agent (N = 1585) or 2-drugs (N = 509) was administered. Overall, pCR was 22.3% (N = 468 patients). The proportion of patients achieving pCR with respect to time interval was, as follows: 12.6% (1st group), 23% (2nd group) and 31.1% (3rd group) (p < 0.001), respectively. The pCR relative risk comparison of 2nd to 1st group was 1.8, while 3rd to 2nd group was 1.3. Moreover, between the 3rd and 1st group, a pCR relative risk of 2.4 (p < 0.01) was noted. At univariate analysis, clinical stage III (p < 0.001), radiotherapy dose >5040 cGy (p = 0.002) and longer interval (p < 0.001) were significantly correlated to pCR. The positive impact of interval (p < 0.001) was confirmed at multivariate analysis as the only correlated factor. CONCLUSION: We confirmed on a population-level that lengthening the interval (>13 weeks) from CRT to surgery improves the pathological response (pCR and pathologic partial response; pPR) in comparison to historic data. Furthermore, radiotherapy dose >5040 cGy and two drugs chemotherapy correlated with pPR rate.

Avaliação do contorno gengival na estética do sorriso / Evaluation of gingival contour in the aesthetic of the smile

Introdução - A definição de parâmetros e padrões estéticos em Odontologia, bem como a satisfação do paciente frente a um tratamento estético vem sendo bastante discutido atualmente por cirurgiões-dentistas de diferentes áreas. O objetivo deste trabalho foi avaliar a influência do contorno gengival na percepção estética de cirurgiões-dentistas e pacientes. Material e Métodos - Dois grupos formados por 30 cirurgiões-dentistas e 30 pacientes avaliaram 6 figuras com diferentes contornos gengivais de modo a se determinar os contornos mais agradáveis para cada grupo.Os resultados foram avaliados estatisticamente pelo teste Mann-Whitney e Kruskal-Wallis. Resultados - Não houve diferença estatisticamente significante entre os grupos quanto à escolha dos sorrisos mais agradáveis para todas as figuras, com exceção da Figura 3. As Figuras 3, 5 e 7 foram avaliadas positivamente e as Figuras 4, 6 e 8 não foram aceitas por ambos os grupos. Conclusão - Os dois grupos estudados têm escolhas semelhantes quanto à maioria dos contornos gengivais.Os sorrisos mais harmônicos transmitem uma sensação mais agradável aos observadores.

Introduction - The definition of aesthetics guidelines and standards in Dentistry, as well the patient's satisfaction with the aesthetic outcome is a subject that has been discussed between dentists from different areas. The aim of this study was to evaluate the influence of gingival contour in the aesthetic perception of dentists and patients. Material and Methods - Six photos with different gingival contours were classified by 2 experimental groups, dentists and patients to determine the most pleasant contours for each group. The results were submitted to Mann-Whitney and Kruskal-Wallis statistical analysis. Results - There was no statistically significant difference between the groups in the choices for the more pleasant smile, except by the Figure 3. Figures 3, 5 and 7 were positively evaluated. Figures 4, 6 and 8 weren't accepted as pleasant by both groups. Conclusion - Both dentists and patients had similar views of the most gingival contours. The harmonic smiles transmitted a pleasant sensation to the observers.

Prevalência de indivíduos cor-deficientesentre alunos de odontologia / Prevalence of color vision-deficient individuals among dental students

O objetivo deste estudo foi identificar indivíduos deficientespara visão de cores, testando a acuidade visualdentre um grupo de estudantes de Odontologia, e compararo resultado obtido com os resultados encontradosna literatura, considerando o prejuízo das discromatopsiascongênitas para a Odontologia, especialmente naescolha da cor dental. Foram escolhidas seis cartas determinadasdentre as cartas da seqüência do Teste de Ishiharae essas foram apresentadas como seis ôslidesõ para 308indivíduos, alunos de Odontologia. Durante a apresentação,o indivíduo preenchia um formulário com suasinformações pessoais e a leitura da carta que estava vendo.O Teste de Ishihara é um teste de leitura de placas pseudo-isocromáticas usado para identificar indivíduos comdiscromatopsias congênitas; e é o mais usado dos testespara esse fim. Trezentos e oito indivíduos foram avaliados.Desses, 121 (39,3 por cento) eram homens e 187 (60,7 por cento) erammulheres, com idades entre 19 e 37 anos. Do total, 13(4,2 por cento) foram considerados indivíduos cor-deficientes: 8(6,6 por cento) homens e 5 (2,6 por cento) mulheres. Após a análise estatística,pudemos afirmar que, com 95 por cento de probabilidade,a proporção real de homens cor-deficientes está nointervalo de 3,14 por cento a 12,16 por cento; e a proporção real de mulherescor-deficientes está no intervalo de 0,96 por cento a 5,68 por centoRejeitamos a hipótese de que a população feminina desteestudo está de acordo com a encontrada na literatura.Por outro lado, a população masculina deste estudo pareceestar de acordo com os achados da literatura.