Abstract Purpose Provide a simple research tool that may be used to calculate the NCTP or TCP of a particular treatment plan. Illustrate the implementation of the EUD-based NTCP and TCP models as a ...research tool. Methods and materials A high-level computing language was chosen to implement Niemierko's EUD-based NTCP and TCP mathematical models. The necessary treatment planning software requirements were clearly defined. Results The computer code is presented and explained. Six simple examples were created to quickly troubleshoot the reader's code implementation. A table of model parameters based on the Emami data was generated.
Abstract
Background
Improved prognostication of oropharyngeal squamous cell carcinoma (OPSCC) may facilitate individualized patient management. The goal of this study was to develop and validate a ...prognostic signature based on microRNA sequencing (miRNA-seq) analysis.
Methods
We collected tumor specimens for miRNA-seq analysis from OPSCC patients treated at Washington University in St Louis (n = 324) and Vanderbilt University (n = 130). OPSCC patients (n = 79) from The Cancer Genome Atlas Program were also included for independent validation. Univariate and multivariable Cox regression analyses were performed to identify miRNAs associated with disease outcomes. All statistical tests were 2-sided.
Results
By miRNA-seq profiling analysis, we identified a 26-miRNA signature. Based on computed risk scores of the signature, we classified the patients into low- and high-risk groups. In the training cohort, the high-risk group had much shorter overall survival compared with the low-risk group (hazard ratio HR = 3.80, 95% confidence interval CI = 2.37 to 6.10, P < .001). Subgroup analysis further revealed that the signature was prognostic for HPV-positive OPSCCs (HR = 3.07, 95% CI = 1.65 to 5.71, P < .001). Multivariable analysis indicated that the signature was independent of common clinicopathologic factors for OPSCCs. Importantly, the miRNA signature was a statistically significant predictor of overall survival in independent validation cohorts (The Cancer Genome Atlas Program cohort: HR = 6.05, 95% CI = 2.10 to 17.37, P < .001; Vanderbilt cohort: HR = 7.98, 95% CI = 3.99 to 15.97, P < .001; Vanderbilt HPV-positive cohort: HR = 8.71, 95% CI = 2.70 to 28.14, P < .001).
Conclusions
The miRNA signature is a robust and independent prognostic tool for risk stratification of OPSCCs including HPV-positive OPSCCs.
During the coronavirus disease 2019 (COVID‐19) pandemic, providers and patients must engage in shared decision making regarding the pros and cons of early versus delayed interventions for localized ...skin cancer. Patients at highest risk of COVID‐19 complications are older; are immunosuppressed; and have diabetes, cancer, or cardiopulmonary disease, with multiple comorbidities associated with worse outcomes. Physicians must weigh the patient's risk of COVID‐19 complications in the event of exposure against the risk of worse oncologic outcomes from delaying cancer therapy. Herein, the authors have summarized current data regarding the risk of COVID‐19 complications and mortality based on age and comorbidities and have reviewed the literature assessing how treatment delays affect oncologic outcomes. They also have provided multidisciplinary recommendations regarding the timing of local therapy for early‐stage skin cancers during this pandemic with input from experts at 11 different institutions. For patients with Merkel cell carcinoma, the authors recommend prioritizing treatment, but a short delay can be considered for patients with favorable T1 disease who are at higher risk of COVID‐19 complications. For patients with melanoma, the authors recommend delaying the treatment of patients with T0 to T1 disease for 3 months if there is no macroscopic residual disease at the time of biopsy. Treatment of tumors ≥T2 can be delayed for 3 months if the biopsy margins are negative. For patients with cutaneous squamous cell carcinoma, those with Brigham and Women's Hospital T1 to T2a disease can have their treatment delayed for 2 to 3 months unless there is rapid growth, symptomatic lesions, or the patient is immunocompromised. The treatment of tumors ≥T2b should be prioritized, but a 1‐month to 2‐month delay is unlikely to worsen disease‐specific mortality. For patients with squamous cell carcinoma in situ and basal cell carcinoma, treatment can be deferred for 3 months unless the individual is highly symptomatic.
During the coronavirus disease 2019 (COVID‐19) pandemic, providers must help patients to make informed decisions regarding skin cancer management and assess the risk of potential COVID‐19–associated morbidity and/or mortality versus primary skin cancer morbidity and/or mortality. In this article, the authors summarize current data regarding the risk of COVID‐19 complications and mortality based on age and comorbidities, and review the literature assessing how treatment delays affect oncologic outcomes. They provide multidisciplinary recommendations regarding the timing of local therapy for patients with early‐stage skin cancers.
Purpose:
Severe artifacts in kilovoltage-CT simulation images caused by large metallic implants can significantly degrade the conspicuity and apparent CT Hounsfield number of targets and anatomic ...structures, jeopardize the confidence of anatomical segmentation, and introduce inaccuracies into the radiation therapy treatment planning process. This study evaluated the performance of the first commercial orthopedic metal artifact reduction function (O-MAR) for radiation therapy, and investigated its clinical applications in treatment planning.
Methods:
Both phantom and clinical data were used for the evaluation. The CIRS electron density phantom with known physical (and electron) density plugs and removable titanium implants was scanned on a Philips Brilliance Big Bore 16-slice CT simulator. The CT Hounsfield numbers of density plugs on both uncorrected and O-MAR corrected images were compared. Treatment planning accuracy was evaluated by comparing simulated dose distributions computed using the true density images, uncorrected images, and O-MAR corrected images. Ten CT image sets of patients with large hip implants were processed with the O-MAR function and evaluated by two radiation oncologists using a five-point score for overall image quality, anatomical conspicuity, and CT Hounsfield number accuracy. By utilizing the same structure contours delineated from the O-MAR corrected images, clinical IMRT treatment plans for five patients were computed on the uncorrected and O-MAR corrected images, respectively, and compared.
Results:
Results of the phantom study indicated that CT Hounsfield number accuracy and noise were improved on the O-MAR corrected images, especially for images with bilateral metal implants. Theγ pass rates of the simulated dose distributions computed on the uncorrected and O-MAR corrected images referenced to those of the true densities were higher than 99.9% (even when using 1% and 3 mm distance-to-agreement criterion), suggesting that dose distributions were clinically identical. In all patient cases, radiation oncologists rated O-MAR corrected images as higher quality. Formerly obscured critical structures were able to be visualized. The overall image quality and the conspicuity in critical organs were significantly improved compared with the uncorrected images: overall quality score (1.35 vs 3.25, P = 0.0022); bladder (2.15 vs 3.7, P = 0.0023); prostate and seminal vesicles/vagina (1.3 vs 3.275, P = 0.0020); rectum (2.8 vs 3.9, P = 0.0021). The noise levels of the selected ROIs were reduced from 93.7 to 38.2 HU. On most cases (8/10), the average CT Hounsfield numbers of the prostate/vagina on the O-MAR corrected images were closer to the referenced value (41.2 HU, an average measured from patients without metal implants) than those on the uncorrected images. High γ pass rates of the five IMRT dose distribution pairs indicated that the dose distributions were not significantly affected by the CT image improvements.
Conclusions:
Overall, this study indicated that the O-MAR function can remarkably reduce metal artifacts and improve both CT Hounsfield number accuracy and target and critical structure visualization. Although there was no significant impact of the O-MAR algorithm on the calculated dose distributions, we suggest that O-MAR corrected images are more suitable for the entire treatment planning process by offering better anatomical structure visualization, improving radiation oncologists’ confidence in target delineation, and by avoiding subjective density overrides of artifact regions on uncorrected images.
Objective
To evaluate the long‐term bowel‐associated quality of life (QOL) in men after radiotherapy (RT) for prostate cancer with and without the use of rectal hydrogel spacer.
Patients and Methods
...The patients’ QOL was examined using the Expanded Prostate Cancer Index Composite (EPIC) and mean changes from baseline in EPIC domains were evaluated. A total of 215 patients from a randomised multi‐institutional trial of RT, with or without hydrogel spacer, with a QOL endpoint were pooled with 165 non‐randomised patients from a single institution with prospective QOL collection in patients with or without hydrogel spacer. The proportions of men with minimally important differences (MIDs) relative to pre‐treatment baseline in the bowel domain were tested using repeated measure logistic models with a pre‐specified threshold for clinically significant declines (≥5 equivalent to MIDx1 and ≥10 equivalent to MIDx2).
Results
A total of 380 men were evaluated (64% with spacer and 36% without) with QOL data being available for 199 men with >24 months of follow‐up median (range) 39.5 (31–71.4) months. Treatment with spacer was associated with less decline in average long‐term bowel QOL (89.4 for control and 94.7 for spacer) with differences at >24 months meeting the threshold of a MID difference between cohorts (bowel score difference from baseline: control = −5.1, spacer = 0.3, difference = −5.4; P < 0.001). When evaluated over time men without spacer were more likely to have MIDx1 (5 points) declines in bowel QOL (P = 0.01). At long‐term follow‐up MIDx1 was 36% without spacer vs 14% with spacer (P <0.001; odds ratio OR 3.5, 95% CI 1.7–6.9) while MIDx2 was seen in 19% vs 6% (P = 0.008; OR 3.6, 95% CI 1.4–9.1). The use of spacer was associated with less urgency with bowel movements (P = 0.002) and fewer loose stools (P = 0.009), as well as less bother with urgency (P = 0.007) and frequency of bowel movements (P = 0.009).
Conclusions
In this pooled analysis of QOL after prostate RT with up to 5 years of follow‐up, use of a rectal spacer was associated with preservation of bowel QOL. This QOL benefit was preserved with long‐term follow‐up.
Preventive care and routine clinic visits declined sharply, limiting cancer care to patients who were symptomatic. ...during lockdown, many patients could not travel to access necessary services, ...further complicating cancer care. Cooperative Institute for Research in the Atmosphere at Colorado State and the National Oceanic and Atmospheric Administration 2017 Hurricane Maria Hurricane Maria brought major hurricane (category 3–5) winds to five small island states and tropical storm force winds to 11 more. Deluging rains produced precipitation extremes exceeding 1 m. Wind damage, torrential rains, flash floods, and widespread landslides contributed to extensive devastation and disruption of electrical power, transportation, water, and supply chains for food, medicine, and fuel, with long-lasting physical and mental health consequences for the citizens.
Caribbean small island developing states are becoming increasingly vulnerable to compounding disasters, prominently featuring climate-related hazards and pandemic diseases, which exacerbate existing ...barriers to cancer control in the region. We describe the complexities of cancer prevention and control efforts throughout the Caribbean small island developing states, including the unique challenges of people diagnosed with cancer in the region. We highlight potential solutions and strategies that concurrently address disaster adaptation and cancer control. Because Caribbean small island developing states are affected first and worst by the hazards of compounding disasters, the innovative solutions developed in the region are relevant for climate mitigation, disaster adaptation, and cancer control efforts globally. In the age of complex and cascading disaster scenarios, developing strategies to mitigate their effect on the cancer control continuum, and protecting the health and safety of people diagnosed with cancer from extreme events become increasingly urgent. The equitable development of such strategies relies on collaborative efforts among professionals whose diverse expertise from complementary fields infuses the local community perspective while focusing on implementing solutions.
Current recommendations regarding the size of local excision (LE) margins for Merkel cell carcinoma (MCC) have not been well established.
To assess whether larger clinical LE margins and receipt of ...adjuvant radiotherapy are associated with improvements in overall survival (OS) among patients with localized MCC.
This large multicenter retrospective cohort study used records from the National Cancer Database to identify adult patients with localized stage I or stage II MCC who underwent LE between January 1, 2004, and December 31, 2015. Data were analyzed from August 1, 2020, to January 25, 2021.
Local excision margin size and adjuvant radiotherapy.
Overall and net survival were assessed using Cox multivariable regression analysis.
A total of 6156 patients with localized MCC (median age at diagnosis, 77 years range, 27-90 years; 2500 women 40.6%). In the multivariable regression analysis, LE clinical margins larger than 1.0 cm were associated with improvements in OS (HR, 0.88; 95% CI, 0.81-0.95; P < .001) compared with margins of 1.0 cm or smaller, regardless of tumor subsite. At 5 years after surgery, LE margins of 1.0 cm or smaller were associated with a net survival of 76.7%, while LE margins larger than 1.0 cm were associated with a net survival of 89.8% (P < .001). Stratification of LE margins into 3 subgroups indicated that LE margins of 1.1 to 2.0 cm (HR, 0.87; 95% CI, 0.76-0.99; P = .047) and larger than 2.0 cm (HR, 0.84; 95% CI, 0.72-0.98; P = .03) were associated with improvements in OS compared with margins of 1.0 cm or smaller. In patients with less aggressive disease (ie, those who were immunocompetent and had tumors ≤1.0 cm, no lymphovascular invasion, and negative pathologic margins), LE margins larger than 1.0 cm were also associated with improvements in OS (HR, 0.87; 95% CI, 0.78-0.97; P = .01). Among patients who received adjuvant radiotherapy, larger LE margins were associated with improvements in OS (HR, 0.87; 95% CI, 0.76-0.98; P = .03). Receipt of adjuvant radiotherapy was also associated with improvements in OS within the 3 LE margin subgroups. Patients who received adjuvant radiotherapy and had LE margins of 1.0 cm or smaller (HR, 0.81; 95% CI, 0.74-0.89; P < .001) experienced OS that was comparable to that in patients who did not receive adjuvant radiotherapy and had LE margins larger than 1.0 cm (HR, 0.80; 95% CI, 0.71-0.89; P = .87).
In this study, LE clinical margins larger than 1.0 cm were associated with improvements in OS, and these improvements were independent of tumor subsite, receipt of adjuvant radiotherapy, positive pathologic margins, or adverse pathologic features for stage I to stage II MCC. Patients with LE margins of 1.0 cm or smaller who received adjuvant radiotherapy experienced OS that was similar to that of patients with larger LE margins who did not receive radiotherapy. The combination of LE clinical margins larger than 1.0 cm and adjuvant radiotherapy was associated with the highest OS.
For patients with unfavorable or high-risk prostate cancer, dose escalated radiation therapy leads to improved progression free survival but attempts to deliver increased dose by external beam ...radiation therapy (EBRT) alone can be limited by late toxicities to nearby genitourinary and gastrointestinal organs at risk. Brachytherapy is a method to deliver dose escalation in conjunction with EBRT with a potentially improved late toxicity profile and improved prostate cancer related outcomes. At least three randomized controlled trials have demonstrated improved biochemical control with the addition of either low-dose rate (LDR) or high-dose rate (HDR) brachytherapy to EBRT, although only ASCENDE-RT compared brachytherapy to dose-escalated EBRT but did report an over 50% improvement in biochemical failure with a LDR boost. Multiple single institution and comparative research series also support the use of a brachytherapy boost in the DE-EBRT era and demonstrate excellent prostate cancer specific outcomes. Despite improved oncologic outcomes with a brachytherapy boost in the high-risk setting, the utilization of both LDR, and HDR brachytherapy use is declining. The acute genitourinary toxicities when brachytherapy boost is combined with EBRT, particularly a LDR boost, are of concern in comparison to EBRT alone. HDR brachytherapy boost has many physical properties inherent to its rapid delivery of a large dose which may reduce acute toxicities and also appeal to the radiobiology of prostate cancer. We herein review the evidence for use of either LDR or HDR brachytherapy boost for high-risk prostate cancer and summarize comparisons between the two treatment modalities.
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