A deeply supervised attention-enabled boosted convolutional neural network (DAB-CNN) is presented as a superior alternative to current state-of-the-art convolutional neural networks (CNNs) for ...semantic CT segmentation. Spatial attention gates (AGs) were incorporated into a novel 3D cascaded CNN framework to prioritize relevant anatomy and suppress redundancies within the network. Due to the complexity and size of the network, incremental channel boosting was used to decrease memory usage and facilitate model convergence. Deep supervision was used to encourage semantically meaningful deep features and mitigate local minima traps during training. The accuracy of DAB-CNN is compared to seven architectures: a variation of U-Net (UNet), attention-enabled U-Net (A-UNet), boosted U-Net (B-UNet), deeply-supervised U-Net (D-UNet), U-Net with ResNeXt blocks (ResNeXt), life-long learning segmentation CNN (LL-CNN), and deeply supervised attention-enabled U-Net (DA-UNet). The accuracy of each method was assessed based on Dice score compared to manually delineated contours as the gold standard. One hundred and twenty patients who had definitive prostate radiotherapy were used in this study. Training, validation, and testing followed Kaggle competition rules, with 80 patients used for training, 20 patients used for internal validation, and 20 test patients used to report final accuracies. Comparator p -values indicate that DAB-CNN achieved significantly superior Dice scores than all alternative algorithms for the prostate, rectum, and penile bulb. This study demonstrated that attention-enabled boosted convolutional neural networks (CNNs) using deep supervision are capable of achieving superior prediction accuracy compared to current state-of-the-art automatic segmentation methods.
The two types of nonmelanoma skin cancer most apt to metastasize to lymph nodes are cutaneous squamous cell carcinoma and Merkel cell carcinoma. The clinical impact of nodal metastases of these ...cancers is substantial, resulting in intensification of treatment and morbidity and worsened cancer outcomes. Exact best practices are challenging to define as many specific clinical scenarios remain incompletely catalogued, characterized, or studied. In general, the role of radiation therapy is indisputably established as part of the treatment of both of these diseases although its success depends on the best available assessment of extent of disease and appropriate integration into the multimodality care plan.
Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, ...and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome.
A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies.
Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration.
Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients’ factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery).
Undifferentiated pleomorphic sarcoma (UPS) encompasses rare neoplasms that can arise either in the dermis or in the subfascial soft tissue. The behavior of UPS ranges from indolent to aggressive, but ...data predicting outcomes are limited.
Identify predictors of poor outcomes by analyzing a large collection of UPS cases.
We evaluated all available cases of UPS (including those termed atypical fibroxanthoma, malignant fibrous histiocytoma, pleomorphic dermal sarcoma, and subfascial UPS) across 3 tertiary care centers.
Among the 319 patients, 45 experienced recurrence, 33 experienced metastasis, and 96 died of any cause. Risk factors for recurrence were clinical tumor size larger than 5 cm and invasion beyond subcutaneous fat. Risk factors for distant metastases were tumor site, tumor size larger than 2 cm, invasion beyond subcutaneous fat, and lymphovascular invasion. Risk factors for overall mortality were age, immunosuppression, tumor size larger than 2 cm, and lymphovascular invasion. History of skin cancer was associated with a lower risk of recurrence and metastasis.
This was a retrospective study.
Using the unbiased approach of pooling all UPS cases regardless of terminology, we identified clinical and histologic factors predicting poor outcomes. We propose subcategorization of UPS (into superficial versus deep UPS), which is consistent with the American Joint Committee on Cancer staging of soft-tissue sarcoma.
The treatment of nasopharyngeal carcinoma requires high radiation doses. The balance of the risks of local recurrence owing to inadequate tumor coverage versus the potential damage to the adjacent ...organs at risk (OARs) is of critical importance. With advancements in technology, high target conformality is possible. Nonetheless, to achieve the best possible dose distribution, optimal setting of dose targets and dose prioritization for tumor volumes and various OARs is fundamental. Radiation doses should always be guided by the As Low As Reasonably Practicable principle. There are marked variations in practice. This study aimed to develop a guideline to serve as a global practical reference.
A literature search on dose tolerances and normal-tissue complications after treatment for nasopharyngeal carcinoma was conducted. In addition, published guidelines and protocols on dose prioritization and constraints were reviewed. A text document and preliminary set of variants was circulated to a panel of international experts with publications or extensive experience in the field. An anonymized voting process was conducted to rank the proposed variants. A summary of the initial voting and different opinions expressed by members were then recirculated to the whole panel for review and reconsideration. Based on the comments of the panel, a refined second proposal was recirculated to the same panel. The current guideline was based on majority voting after repeated iteration for final agreement.
Variation in opinion among international experts was repeatedly iterated to develop a guideline describing appropriate dose prioritization and constraints. The percentage of final agreement on the recommended parameters and alternative views is shown. The rationale for the recommendations and the limitations of current evidence are discussed.
Through this comprehensive review of available evidence and interactive exchange of vast experience by international experts, a guideline was developed to provide a practical reference for setting dose prioritization and acceptance criteria for tumor volumes and OARs. The final decision on the treatment prescription should be based on the individual clinical situation and the patient's acceptance of optimal balance of risk.
Nasopharyngeal carcinoma (NPC) is caused by Epstein-Barr virus (EBV) infection, yet incorporating measurement of EBV DNA levels into clinical practice remains a challenge. Here, we summarize the ...relationship between NPC and EBV infection before describing the use of cell-free DNA as a plasma biomarker in cancer. We then compare conventional polymerase chain reaction methods and emerging next-generation sequencing approaches for EBV viral load detection emphasizing their prognostic and predictive utility. We conclude by considering how assay standardization, novel molecular approaches, and alternative clinical specimens may be leveraged to bring EBV testing into the routine care of patients with NPC.
This cross-sectional study aimed to assess the awareness among United States (US) oncologists about oral medicine (OM) as a specialty of dentistry, and their collaboration with OM providers.
An ...online survey was conducted, inviting 1350 US oncologists, with data collected on demographics, practice background, comfort level with diagnosing and treating oral conditions, referral practices for oral conditions, and more.
Of the invited 1350 oncologists, 192 responded (14% response rate). Among respondents, 46% were familiar with the OM specialty. Of these, 73% had previously sought consultation from OM specialists. The primary reasons for referral included dental clearance before initiating chemotherapy (38.5%), dental clearance before initiating radiotherapy (37%), and managing oral ulcers and oral potentially malignant disorders equally (32.2%). Regarding referrals to providers outside of OM, oncologists primarily referred patients with oral lesions to otolaryngologists (64.6%), followed by oral and maxillofacial surgeons (55.2%) and general dentists (45.3%).
Our study showed that over half of US oncologists were unfamiliar with the OM specialty. However, the referral rate to OM providers was high among oncologists who had prior OM knowledge. It is advisable to enhance the collaboration between OM and oncology specialists to ensure optimal care for patients with cancer.
•Locally advanced primary and metastatic nodal NMSC is primarily treated with surgery.•Though data is lacking adjuvant RT is often used in setting of high-risk pathological features.•High-risk ...features include PNI, positive surgical margins and node-positivity.•Definitive RT should be considered where surgery is contraindicated or refused.•Stereotactic RT may have utility in the setting of inoperable recurrence or intracranial disease.
Non-melanomatous skin cancers (NMSC), comprising both cutaneous squamous cell carcinomas (SCC) and basal cell carcinomas (BCC), are the most common malignancies in fair-skinned persons, frequently arising in the sun-exposed head and neck region. Simple surgical excision is usually curative in the majority of low-risk cases, when functional and cosmetic preservation is typically easily achieved. A number of factors portend a more aggressive course in localised lesions, including pathological features such as an involved surgical margin, moderate to poor differentiation, or perineural or lymphovascular invasion, and clinical features including immunosuppression and recurrent cancer status. Though high-level evidence is lacking, consensus guidelines consistently recommend adjuvant radiotherapy in high-risk NMSCs, most commonly in the setting of a positive margin or extensive perineural disease. In non-operative candidates, high-dose radiotherapy can provide long-term control and survival. In SCC, high risk lesions pose an increased risk of regional spread, and consideration should be given to elective nodal treatment, either with neck dissection or irradiation. Development of regional disease, often to the parotid or cervical nodes in the head and neck region, shifts the prognosis substantially and combined therapy consisting of surgery and radiotherapy is then recommended. Limited evidence supports the use of the emerging technologies of protons, heavy particles or stereotactic treatment, but they may be considered in the setting of intracranial perineural spread or the reirradiation setting, when the radiation dosimetry is exceptionally complex. This review aims to provide an update on the current use of radiation in the treatment of locally advanced NMSCs.
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