Prognostic factors of survival in patients with malignant pleural mesothelioma: an analysis of the National Cancer Database.

Malignant pleural mesothelioma (MPM) is a rare disease with a very poor prognosis. Previous studies have indicated that women experience longer survival compared with men. We analyzed 16 267 eligible patients (21.3% females) in the National Cancer Database to evaluate which clinical factors are independently predictive of longer survival. After adjusting for all covariates, survival was significantly better in females compared with males [HRadj: 0.81, 95% confidence interval (CI): 0.77-0.85]. Other factors significantly associated with better survival were younger age at diagnosis, higher income, lower comorbidity score, epithelial histology, earlier stage and receipt of surgical or medical treatment. After propensity matching, survival was significantly better for females compared with males [hazard ratio (HR): 0.86, 95% CI: 0.80-0.94]. After propensity matching within the epithelial group, survival remained significantly better for females compared with males (HR: 0.85, 95% CI: 0.74-0.97). This study adds information to the known significant gender survival difference in MPM by disentangling the effect of gender from the effect of age and histology, two known independent factors affecting survival. Circulating estrogen, present in young but not older women, and higher expression of the estrogen receptor beta in epithelial mesothelioma have been suggested to play a role in gender survival differences. These findings may lead to exploring new therapeutic options, such as targeting estrogen receptor beta, and considering hormonal therapy including estrogens for patients with otherwise limited prognosis.

Stereotactic body radiation therapy (SBRT) improves local control and overall survival compared to conventionally fractionated radiation for stage I non-small cell lung cancer (NSCLC).

BACKGROUND: Stereotactic body radiotherapy (SBRT) has been adopted as the standard of care for inoperable early-stage non-small cell lung cancer (NSCLC), with local control rates consistently >90%. However, data directly comparing the outcomes of SBRT with those of conventionally fractionated radiotherapy (CONV) is lacking. MATERIAL AND METHODS: Between 1990 and 2013, 497 patients (525 lesions) with early-stage NSCLC (T1-T2N0M0) were treated with CONV (n = 127) or SBRT (n = 398). In this retrospective analysis, five endpoints were compared, with and without adjusting for clinical and dosimetric factors. Competing risks analysis was performed to estimate and compare the cumulative incidence of local failure (LF), nodal failure (NF), distant failure (DF) and disease progression. Overall survival (OS) was estimated by the Kaplan-Meier method and compared by the Cox regression model. Propensity score (PS) matched analysis was performed based on seven patient and clinical variables: age, gender, Karnofsky performance status (KPS), histology, T stage, biologically equivalent dose (BED), and history of smoking. RESULTS: The median dose delivered for CONV was 75.6 Gy in 1.8-2.0 Gy fractions (range 60-90 Gy; median BED = 89.20 Gy) and for SBRT 48 Gy in four fractions (45-60 Gy in three to five fractions; median BED = 105.60 Gy). Median follow-up was 24.4 months, and 3-year LF rates were 34.1% with CONV and 13.6% with SBRT (p < .001). Three-year OS rates were 38.9 and 53.1%, respectively (p = .018). PS matching showed a significant improvement of OS (p = .0497) for SBRT. T stage was the only variable correlating with all five endpoints. CONCLUSION: SBRT compared to CONV is associated with improved LF rates and OS. Our data supports the continued use and expansion of SBRT as the standard of care treatment for inoperable early-stage NSCLC.

Affluence and Breast Cancer.

High income, high socioeconomic status, and affluence increase breast cancer incidence. Socioeconomic status in USA breast cancer studies has been assessed by block-group socioeconomic measures. A block group is a portion of a census tract with boundaries that segregate, as far as possible, socioeconomic groups. In this study, we used US Census income data instead of block groups to gauge socioeconomic status of breast cancer patients in relationship with incidence, prognostic markers, and survival. US state breast cancer incidence and mortality data are from the U.S. Cancer Statistics Working Group, United States Cancer Statistics: 1999-2011. Three-Year-Average Median Household Income by State, 2010 to 2012, is from the U.S. Census Bureau, Current Population Survey, 2011 to 2013 Annual Social and Economic Supplements. County incomes are from the 2005-2009 American Community Survey of the U.S. Census Bureau. The American Community Survey is an ongoing statistical survey that samples a small percentage of the population yearly. Its purpose is to provide communities the information they need to plan investments and services. Breast cancer county incidence and survival data are from the National Cancer Institute's Surveillance, Epidemiology and End Results Program (SEER) data base. We analyzed SEER data from 198 counties in California, Connecticut, Georgia, Hawaii, Iowa, New Mexico, Utah, and Washington. SEER uses the Collaborative Stage (CS) Data Collection System. We have retained the SEER CS variables. There was a significant relationship of income with breast cancer incidence in 50 USA states and the District of Columbia in White women (r = 0.623, p < 0.001). There was a significant relationship between node involvement and income in Whites in 198 USA counties. Income was significantly correlated with 5-year relative survival in Whites with localized breast cancer. Income was not correlated with 5-year survival of Black race (p = 0.364) or other races (p = 0.624). The multivariate general linear model with income as covariate, 5-year survival by race as a dependent variable, showed a significant effect of income and White race on 5-year survival (p < 0.001), unrelated to Black race (p = 0.780) or other races (p = 0.618). In men, we found a nonsignificant positive correlation between county breast cancer incidence and income (r = 0.098, p = 0.168). Breast cancer risk factors, such as delayed childbirth, less breast-feeding, and use of hormone supplements, are more common in affluent women. Affluent women are more likely to have mammograms, which detect many cancers that might not otherwise be diagnosed. In addition, women in certain affluent ethnic groups-Ashkenazi Jews, Icelanders and the Dutch-are more likely to carry genetic mutations known to predispose to breast cancer. We hypothesize that women with more income can afford better cancer care and survive longer than poorer women. But our hypothesis does not explain why this effect should be limited to White women; or why node involvement increased with income in White women but not in Blacks or Hispanics. Further studies may be worthwhile.

Geometric dose prediction model for hemithoracic intensity-modulated radiation therapy in mesothelioma patients with two intact lungs.

The presence of two intact lungs makes it challenging to reach a tumoricidal dose with hemithoracic pleural intensity-modulated radiation therapy (IMRT) in patients with malignant pleural mesothelioma (MPM) who underwent pleurectomy/decortications or have unresectable disease. We developed an anatomy-based model to predict attainable prescription dose before starting optimization. Fifty-six clinically delivered IMRT plans were analyzed regarding correlation of prescription dose and individual and total lung volumes, planning target volume (PTV), ipsilateral normal lung volume and ratios: contralateral/ipsilateral lung (CIVR); contralateral lung/PTV (CPVR); ipsilateral lung /PTV (IPVR); ipsilateral normal lung /total lung (INTLVR); ipsilateral normal lung/PTV (INLPVR). Spearman's rank correlation and Fisher's exact test were used. Correlation between mean ipsilateral lung dose (MILD) and these volume ratios and between prescription dose and single lung mean doses were studied. The prediction models were validated in 23 subsequent MPM patients. CIVR showed the strongest correlation with dose (R=0.603,p<0.001) and accurately predicted prescription dose in the validation cases. INLPVR and MILD as well as MILD and prescription dose were significantly correlated (R=-0.784,p<0.001 and R=0.554,p<0.001, respectively) in the training and validation cases. Parameters obtainable directly from planning scan anatomy predict achievable prescription doses for hemithoracic IMRT treatment of MPM patients with two intact lungs. PACS number(s): 87.55.de, 87.55.dk.

Lack of Correlation between Benign Brain Tumors and Markers of Oral Health.

UNLABELLED: Case control studies implicating dental X-rays in the genesis of intracranial meningiomas have yielded conflicting results. To further evaluate what risk, if any, that intracranial meningioma might be associated with dental X-rays, we examined the association of benign brain tumor incidence with the number of dentists and other correlates of oral health in U.S. states and the District of Columbia. We compared these correlations to the association of the same markers of oral health with Alzheimer's death rates. Poor oral health, especially periodontal disease, is a well-established risk factor for dementia. RESULTS: Pearson correlations, number of cases (49, no data from Kansas or Maryland) and significance (2 tailed p values) of benign brain tumor incidence and parameters of oral health are presented. None of the correlations approached statistical significance. In contrast, Alzheimer's deaths by state were negatively correlated with number of dentists and other markers of oral health. CONCLUSION: Our finding of a total lack of correlation between benign brain tumors and markers of oral health and, by implication, dental X-rays, suggests there may be no relationship between dental X-rays and meningioma or other benign brain tumors. This conclusion is strengthened by our demonstration of the known negative correlation between Alzheimer's and dental care.

ACR Appropriateness Criteria® nonsurgical treatment for locally advanced non-small-cell lung cancer: good performance status/definitive intent.

Concurrent chemotherapy/radiotherapy has been considered the standard treatment for patients with a good performance status and inoperable stage III non-small-cell lung cancer (NSCLC). Three-dimensional chemoradiation therapy and intensity-modulated radiation therapy have been reported to reduce toxicity and allow a dose escalation to 70 Gy and beyond. However, the Radiation Therapy Oncology Group 0617 trial recently showed that dose escalation from 60 Gy to 74 Gy with concurrent chemotherapy in stage III NSCLC was associated with higher toxicity and worse survival. A "one size fits all" treatment approach may need to be changed and adapted to each patient's particular disease and unique biologic/anatomic features, as well as the most appropriate radiotherapy modalities for that patient. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application, by the panel, of a well-established consensus methodology (modified Delphi technique) to rate the appropriateness of imaging and treatment procedures. In instances in which evidence is lacking or not definitive, expert opinion may be used as the basis for recommending imaging or treatment.

Obesity and deranged sleep are independently associated with increased cancer mortality in 50 US states and the District of Columbia.

INTRODUCTION: Proper sleep is associated with reduced cancer risk. For example, multiple studies have found that habitual sleeping pill usage is related to death from cancer, suggesting that sleep derangement may increase cancer mortality. However, other studies have not found a definite connection between sleep and cancer deaths. For this reason, we analyzed US cancer mortality data and sleep quality data to see if there was relationship. METHODS: Age-adjusted data on sleep disturbance in 50 US states and the District of Columbia are from Perceived insufficient rest or sleep among adults--United States, 2008. Age-adjusted all-cancer mortality data are from American Cancer Society Cancer Facts and Figures. Obesity data are from Vital signs: state-specific obesity prevalence among adults--United States, 2009. Data on race by state are from the 2010 US Census (http://www.census.gov). RESULTS: There was a significant correlation between percentage of persons who reported insufficient sleep every day in the preceding 30 days versus all-cancer mortality in 50 US states and the District of Columbia (p < 0.001). Because cancer survival is higher in whites than blacks and lower in obese individuals, multiple linear regression was performed. The association of insufficient sleep every day in the preceding 30 days with all-cancer mortality was significant (p = 0.017), independent of the percentage obese (p < 0.001), and unrelated to percentage white population (p = 0.847). CONCLUSION: Alterations in endocrine function, perhaps abnormal cortisol metabolism resulting from deranged sleep, may be in part responsible for the increased all-cancer mortality we report here. Further studies would be worthwhile.

Outcomes Following SBRT vs. IMRT and 3DCRT for Older Patients with Stage IIA Node-Negative Non-Small Cell Lung Cancer > 5 cm.

BACKGROUND: To describe outcomes and compare the effectiveness of stereotactic body radiotherapy (SBRT) versus 3-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) in patients with stage IIA lymph node-negative (N0) non-small cell lung cancer (NSCLC) tumors > 5 cm. METHODS: We used the SEER-Medicare database (2005-2015) to identify patients > 65 years with stage IIA (AJCC TNM7) N0 NSCLC > 5 cm tumors who were treated with SBRT, IMRT, and 3DCRT. We used propensity score methods with inverse probability weighting to compare lung cancer-specific survival (LCSS), overall survival (OS), and toxicity. RESULTS: Of 584 patients, 88 (15%), 140 (24%), and 356 (61%) underwent SBRT, IMRT, and 3DCRT, respectively. The SBRT group was older (P = .004), had more comorbidities (P = .02), smaller tumors (P = .03), and more adenocarcinomas (P < .0001). We found a trend towards higher median unadjusted OS with SBRT compared to IMRT and 3DCRT (19 vs. 13 and 14 months, respectively, P = .37). In our propensity score-adjusted analyses, SBRT was significantly associated with better OS and LCSS compared to IMRT (HROS: 0.78, 95% CI: 0.68-0.89, HRLCSS: 0.70, 95% CI: 0.60-0.81) and 3DCRT (HROS: 0.81, 95% CI: 0.72-0.93, HRLCSS: 0.80, 95% CI: 0.68-0.93). SBRT-treated patients also had lower overall adjusted complication rates compared to IMRT (OR: 0.74, 95% CI: 0.55-0.99) and 3DCRT (OR: 0.53, 95% CI: 0.40-0.71). CONCLUSION: For patients with NSCLC tumors > 5 cm, SBRT trends towards fewer toxicities and improved survival compared to other forms of radiotherapy. Our findings support SBRT as an appropriate treatment strategy for older patients with larger inoperable NSCLC tumors.

The Rise of Open Access Journals in Radiation Oncology: Influence on Resident Research, 2015 to 2019.

Purpose: While a rising share of scientific research articles are being published in open access (OA) journals, their impact on resident research in radiation oncology is unknown. Thus, we sought to determine the number, content, and costs of first-author, PubMed-searchable articles radiation oncology residents in the United States (US) published in OA journals in recent years. Methods and Materials: We built a database of first-author, PubMed-searchable articles published by US radiation oncology residents who graduated between 2015 and 2019. We then classified each journal in which these articles appeared as either OA or non-OA and obtained the current article-processing charge (APC) for each publication that appeared in an OA journal. Results: The residents in this study published 2637 first-author, PubMed-searchable articles, 555 of which (21.0%) appeared in 138 OA journals. The number of publications in OA journals per resident increased from 0.47 for the class of 2015 to 0.79 for the class of 2019. Publications in OA journals garnered fewer citations than those in non-OA journals (8.9 vs 14.9, P < .01). Furthermore, 90.6% of OA journals levy an APC for original research reports (median, $1896), which is positively correlated with their 2019 impact factor (r = 0.63, P < .01). Aggregate APCs totaled $900,319.21 and appeared to increase over the study period. Conclusions: The number of first-author, PubMed-searchable articles published by graduating US radiation oncology residents in OA journals rose significantly between 2015 and 2019. To maximize the benefits of OA publishing in the future, US radiation oncology residents will need to ensure that they use vetted OA journals to publish their research findings and avoid predatory journals.

The incorporation of cognitive-sparing techniques into prophylactic cranial irradiation in the management of small cell lung cancer.

The use of prophylactic cranial irradiation (PCI) remains an important component in the management of small cell lung cancer (SCLC). This is due to the high rates of subclinical brain metastases at the time of diagnosis. Following a response to initial treatment, PCI historically has been associated with improvements in overall survival and decreased development of brain metastases in patients with limited stage (LS-SCLC) and extensive stage (ES-SCLC) SCLC. However, PCI is commonly withheld in these settings in favor of observation, largely due to its association with cognitive sequelae following treatment. While randomized data has demonstrated that in patients with ES-SCLC, PCI may be withheld in favor of close MRI surveillance without a detriment in overall survival or cognitive functioning, these patients did not undergo formal neuropsychological assessments. In recent years, cognitive sparing techniques incorporated into whole brain radiation therapy and PCI, such as the addition of memantine and hippocampal avoidance, have demonstrated significant improvements in cognitive outcomes. As the overall survival in patients with SCLC continues to improve due to the incorporation of novel systemic therapies (e.g., immune checkpoint inhibitors), the role of PCI and maximizing quality of life remains a highly relevant topic. This article reviews the role of PCI and cognitive-sparing techniques in the management of SCLC.

Recurrent non-small cell lung cancer: evaluation of CT-guided radiofrequency ablation as salvage therapy.

BACKGROUND: Radiofrequency ablation (RFA) is a potential application as a salvage tool after failure of surgery, chemotherapy, or radiotherapy of non-small cell lung cancer (NSCLC). Although several studies have evaluated the use of RFA in primary NSCLC, there is little literature on its potential application as a salvage tool. PURPOSE: To evaluate CT-guided RFA employed as a salvage therapy for pulmonary recurrences of NSCLC after prior treatment with chemotherapy, radiation therapy, and/or surgery. MATERIAL AND METHODS: A retrospective computer database search yielded 33 patients with biopsy proven primary NSCLC who underwent CT-guided RFA of 39 recurrent tumors following surgery, chemotherapy, and/or radiotherapy. Follow-up imaging was performed with CT and PET-CT. The endpoints of interest were progression-free survival (PFS) and time to local progression (TTLP). PFS and TTLP were compared by lesion size (<3 cm, ≥3 cm). RESULTS: The median PFS was 8 months. For patients with a tumor size <3 cm median PFS was 11 months, whereas the median PFS of patients with a tumor size ≥3 cm was 5 months. The difference did not reach statistical significance (P = 0.09). The median TTLP of all tumors was 14 months. TTLP of ablated tumors <3 cm in size was 24 months, compared to 8 months for ablated tumors ≥3 cm in size. The difference did not reach statistical significance (P = 0.07). CONCLUSION: RFA of recurrent NSCLC may be a valuable salvage tool to achieve local tumor control, especially in tumors measuring <3 cm in size.

Risk of Cardiovascular Toxicity According to Tumor Laterality Among Older Patients With Early Stage Non-small Cell Lung Cancer Treated With Radiation Therapy.

BACKGROUND: The long-term risk of cardiovascular outcomes from either stereotactic body radiation therapy (SBRT) or three-dimensional conformal radiation therapy (3DCRT) plus intensity-modulated radiation therapy (IMRT) to treat early stage non-small cell lung cancer (NSCLC) is largely unknown. As continued adoption of SBRT accelerates, it is important to delineate unforeseen cardiovascular risks associated with treatment. RESEARCH QUESTION: Does the long-term risk of cardiovascular outcomes for patients with early stage NSCLC treated with either SBRT or 3DCRT plus IMRT differ by tumor laterality? STUDY DESIGN AND METHODS: Data from the Surveillance, Epidemiology, and End Results registry linked to Medicare was analyzed to identify a sample of 3,256 patients (1,506 treated with SBRT and 1,750 treated with 3DCRT plus IMRT) with node-negative stage I or IIA NSCLC. Cardiovascular events were identified using diagnosis codes, and outcomes were compared between left- and right-sided tumors. We assumed that tumor laterality was random and that the radiation field for left-sided tumors likely would result in greater dose to cardiac tissues. Cox regression models were fit to quantify the association of laterality on outcomes. RESULTS: Patients were followed up for a median of 2 years. Those treated with SBRT showed no difference in hazard of any cardiovascular outcomes by tumor laterality, including the cardiovascular composite (hazard ratio [HR] comparing left- vs right-sided tumors, 0.98; 95% CI, 0.84-1.15). In contrast, patients treated with 3DCRT plus IMRT showed a greater risk of congestive heart failure (HR, 1.23; 95% CI, 1.01-1.48) and percutaneous coronary artery intervention (HR, 2.24; 95% CI, 1.12-4.47). INTERPRETATION: Patients with left- vs right-sided early stage NSCLC showed similar rates of cardiovascular events when treated with SBRT. However, these patients also showed higher rates of select cardiac events when they were treated with 3DCRT plus IMRT. This study provides evidence that SBRT may provide a safer option over 3DCRT plus IMRT for patients with left-sided early stage NSCLC and underscores the need for long-term follow-up for patients treated with radiation therapy.

Characterization of rib fracture development following liver directed stereotactic body radiation therapy.

Purpose: Rib fractures are a well-described complication following thoracic stereotactic body radiation therapy (SBRT). However, there are limited data in the setting of liver-directed SBRT. Methods: Patients who underwent liver SBRT from 2014 to 2019 were analyzed. Logistic regression models were used to identify the demographic, clinical, and dosimetric factors associated with the development of rib fractures. Results: Three hundred and forty-three consecutive patients were reviewed with median follow-up of 9.3 months (interquartile range [IQR]: 4.7-17.4 months); 81% of patients had primary liver tumors and 19% had liver metastases. Twenty-one patients (6.2%) developed rib fractures with a median time to diagnosis of 7 months following SBRT (IQR: 5-19 months). Of those patients, 11 experienced concomitant chest wall pain, while 10 patients had an incidental finding of a rib fracture on imaging. On univariate analysis, female gender (odds ratio [OR]: 2.29; p = 0.05), V30 Gy (OR: 1.02; p < 0.001), V40 Gy (OR: 1.08; p < 0.001), maximum chest wall dose (OR: 1.1; p < 0.001), and chest wall D30 cm3 (OR: 1.09; p < 0.001) were associated with an increased probability of developing a rib fracture. On multivariate analysis, maximum chest wall dose (OR: 1.1; p < 0.001) was associated with developing a rib fracture. Receipt of more than one course of SBRT (p = 0.34), left versus right sided lesion (p = 0.69), osteoporosis (p = 0.54), age (p = 0.82), and PTV volume (p = 0.55) were not significant. Conclusions: Rib fractures following liver SBRT were observed in 6.2% of patients with the majority being asymptomatic. To mitigate this risk, clinicians should minimize dose delivery to the chest wall. Female patients may be at increased risk.

American Radium Society Appropriate Use Criteria for Radiation Therapy in Oligometastatic or Oligoprogressive Non-Small Cell Lung Cancer.

PURPOSE: Recent randomized studies have suggested improvements in progression-free and overall survival with the addition of stereotactic body radiation therapy (SBRT, also known as SABR) in patients with oligometastatic non-small cell lung cancer. Given the novelty and complexity of incorporating SBRT in the oligometastatic setting, the multidisciplinary American Radium Society Lung Cancer Panel was assigned to create appropriate use criteria on SBRT as part of consolidative local therapy for patients with oligometastatic and oligoprogressive non-small cell lung cancer. METHODS AND MATERIALS: A review of the current literature was conducted from January 1, 2008, to December 25, 2020, using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to systematically search the PubMed database to retrieve a comprehensive set of relevant articles. RESULTS: Based on representation in existing randomized trials, the panel defined the term "oligometastasis" as ≤3 metastatic deposits (not including the primary tumor) in the previously untreated setting or after first-line systemic therapy after the initial diagnosis. "Oligoprogression" also referred to ≤3 discrete areas of progression in the setting of prior or ongoing receipt of systemic therapy. In all appropriate patients, the panel strongly recommends enrollment in a clinical trial whenever available. For oligometastatic disease, administering first-line systemic therapy followed by consolidative radiation therapy (to all sites plus the primary/nodal disease) is preferred over up-front radiation therapy. Owing to a dearth of data, the panel recommended that consolidative radiation therapy be considered on a case-by-case basis for 4 to 5 sites of oligometastatic disease, driver mutation-positive oligometastatic disease without progression on up-front targeted therapy, and oligoprogressive cases. CONCLUSIONS: Although SBRT/SABR appears to be both safe and effective in treating patients with limited metastatic sites of disease, many clinical circumstances require individualized management and strong multidisciplinary discussion on account of the limited existing data.

RapidPlan for Knowledge-Based Planning of Malignant Pleural Mesothelioma.

PURPOSE: Treatment planning for malignant pleural mesothelioma is a challenging task due to the relatively large size of the target and the need to spare critical organs that overlap with or are within the target volume. We aimed to develop a knowledge-based model using RapidPlan (RP) for patients with 2 intact lungs. METHODS AND MATERIALS: Data from 57 patients treated with volumetric modulated arc therapy were chosen for training the dose estimation model at a single dose level. The prescription dose was 50.4 Gy in 1.8 Gy fractions. The model was validated on 23 new patients by comparing the clinical plan to the RP. Time taken to plan the RP was compared with that for the clinical plan. RESULTS: For similar target coverage and plan inhomogeneity, RP significantly improved the sparing of the contralateral lung, heart, stomach, esophagus, and ipsilateral kidney. On average, the contralateral lung V5 Gy and V10 Gy were reduced by 13.9% (P < .001) and 7.9% (P < .001), respectively. The mean heart dose was reduced by 5 Gy (P < .001) and V30 Gy by 9.1% (P < .001). Mean dose to the stomach and esophagus were both reduced by 5 Gy (P < .001), and the ipsilateral kidney V18 Gy by 4.1% (P < .001). Mean total lung dose was reduced by 0.8 Gy with RP, which enabled an increase in prescription dose by 1 fraction Absolute volume of ipsilateral lung was adequately spared by both techniques, while sparing of all other organs, namely the cord, liver, and bowel, was not compromised with RP. Time taken with RP was 20 minutes, 45 seconds versus at least 4 hours for an experienced treatment planner. CONCLUSIONS: The RP model for malignant pleural mesothelioma showed improved sparing of critical organs with a reduced treatment planning time and increased prescription dose.

Comparison of Pathologic Complete Response Rates and Oncologic Outcomes in Patients With Surgically Resectable Esophageal Cancer Treated With Neoadjuvant Chemoradiation to 50.4 Gy vs 41.4 Gy.

Background Excellent outcomes and high rates of pathologic complete response (pCR) have been reported in patients with operable esophageal carcinoma using 41.4 Gy of radiation with concurrent carboplatin and paclitaxel. With pCR rates similar to studies using higher doses, it remains unclear whether doses greater than 41.4 Gy result in improved outcomes. This study aims to compare pCR rates and oncologic outcomes in patients treated with neoadjuvant chemoradiation to 50.4 Gy vs 41.4 Gy. Methods We reviewed the charts of patients with operable esophageal carcinoma who were treated with neoadjuvant chemoradiation followed by oncologic resection. Our primary endpoint was the pCR rate. Secondary endpoints were overall survival, progression-free survival (PFS), and toxicity.  Results We identified 43 patients meeting inclusion criteria. Nineteen patients were treated with 41.4 Gy and 24 were treated with 50.4 Gy. Cohorts were well-matched, except for a significantly higher percentage of patients with adenocarcinoma (AC) (89.5% vs 54.2%, p = 0.02), usage of intensity-modulated radiation therapy (IMRT) (100% vs 47.6%; p = 0.002), and usage of carboplatin, plus paclitaxel (100% vs 75%; p = 0.003) in the 41.4 Gy group. The pCR rate for the cohort was 44.2%. No differences in the pCR rate (41.7% vs 47.4%), three-year overall survival (OS) (73.7% vs 77.5%), or three-year PFS (52.8% vs 43.7%) were observed. Late toxicity rates also did not vary significantly (p = 0.2). No grade 4 or 5 events were observed. Conclusion In this small series, there were no differences in the pCR rate, PFS, or OS between those treated with 50.4 Gy and 41.4 Gy. Larger, multi-institutional series are needed to validate these findings.