Is radiation indicated for young women with early stage, node-negative breast cancer after mastectomy? A multi-institution, retrospective review.

The role of post-mastectomy radiation for women with node negative, early stage disease is not well-defined. The purpose of this study is to more clearly define a subset of women who are ≤40 years of age with T1-T2, node negative breast cancer who may benefit from post-mastectomy radiation. Using tumor registries at two institutions, we identified 219 women ≤40 years of age with T1-T2, node negative breast cancer treated with mastectomy. Of these 219 patients, 38 received post-mastectomy radiation and 181 did not. Kaplan-Meier methods and cox proportional-hazards regression models were employed for statistical analysis. There were no locoregional failures in the women receiving post mastectomy radiation, which lead to a nonsignificant increase in freedom from locoregional recurrence (P=.08). For women not receiving post-mastectomy radiation, freedom from locoregional recurrence was 94.7% and 89.7% at 5- and 10-years. Lymphovascular space invasion (LVSI) was the only factor predictive of locoregional recurrence. For women without LVSI, freedom from locoregional recurrence was 96.0% and 93.3% at 5- and 10-years respectively. For women with LVSI who did not receive post mastectomy radiation, freedom from locoregional recurrence was 89.1% at 5-years. There were no failures in the women with LVSI who received post mastectomy radiation. For women ≤40 years of age with T1-2, node negative breast cancer treated with mastectomy and no post-mastectomy radiation, locoregional control is excellent in the absence of LVSI, regardless of other risk factors. In the presence of LVSI (regardless of other risk factors), the risk of locoregional recurrence is high and appears to be decreased with post-mastectomy radiation.

Post-mastectomy Radiotherapy for pT3N0 Breast Cancers: A Retrospective, Multi-Institution Review.

The role of post-mastectomy radiotherapy for pT3N0 breast cancers remains undefined. The purpose of this study was to report institutional outcomes for women with pT3N0 breast cancers treated with and without post-mastectomy radiotherapy. We collected data from two large tumor registries on pT3N0 breast cancers diagnosed between 1985 and 2014. Kaplan-Meier estimates were used to analyze freedom from local-regional recurrence (FFLR), relapse free survival, and overall survival. This analysis identified 93 women with pT3N0 breast cancers. Of these, 53 received post-mastectomy radiotherapy and 40 did not. Median follow-up was 6.2 years and 5.3 years in the non-post-mastectomy radiotherapy and post-mastectomy radiotherapy cohorts, respectively. Women not undergoing post-mastectomy radiotherapy were more likely to be diagnosed in the 1980s and 1990s and were less likely to receive systemic therapies than women receiving post-mastectomy radiotherapy (p < 0.05). There was a trend toward increased FFLR in the women receiving post-mastectomy radiotherapy (p = 0.15). FFLR in the post-mastectomy radiotherapy cohort was 98% at both 5 and 10 years. For women not receiving post-mastectomy radiotherapy, FFLR was 88% at both 5 and 10 years. Women not receiving post-mastectomy radiotherapy in our study had an isolated local-regional failure rate of 12% at 10 years, despite receiving inferior systemic treatment by current standards. Local-regional control after post-mastectomy radiotherapy for pT3N0 breast cancers was excellent. Further research is needed to define post-mastectomy radiotherapy indications for this patient population when receiving chemotherapy and endocrine therapy in line with current guidelines.

The Effect of Radiation on Complication Rates and Patient Satisfaction in Breast Reconstruction using Temporary Tissue Expanders and Permanent Implants.

The optimal method of reconstruction following mastectomy for breast cancer patients receiving radiation therapy (RT) is controversial. This study evaluated patient satisfaction and complication rates among patients who received implant-based breast reconstruction. The specific treatment algorithm analyzed included patients receiving mastectomy and immediate temporary tissue expander (TE), followed by placement of a permanent breast implant (PI). If indicated, RT was delivered to the fully expanded TE. Records of 218 consecutive patients with 222 invasive (85%) or in situ (15%) breast lesions from the Salt Lake City region treated between 1998 and 2009 were retrospectively reviewed, 28% of whom received RT. Median RT dose was 50.4 Gy, and 41% received a scar boost at a median dose of 10 Gy. Kaplan-Meier analyses were performed to evaluate the cumulative incidence of surgical complications, including permanent PI removal. Risk factors associated with surgical events were analyzed. To evaluate cosmetic results and patient satisfaction, an anonymous survey was administered. Mean follow-up was 44 months (range 6-144). Actuarial 5-year PI removal rates for non-RT and RT patients were 4% and 22%, respectively. On multivariate analysis (MVA), the only factor associated with PI removal was RT (p = 0.009). Surveys were returned describing the outcomes of 149 breasts. For the non-RT and RT groups, those who rated their breast appearance as good or better were 63% versus 62%, respectively. Under 1/3 of each group was dissatisfied with their reconstruction. RT did not significantly affect patient satisfaction scores, but on MVA RT was the only factor associated with increased PI removal. This reconstruction technique may be considered an acceptable option even if RT is needed, but the increased complication risk with RT must be recognized.

Feasibility and Clinical Utility of a Workflow Interfacing Radiation Oncology Lung Stereotactic Body Radiation Therapy Treatment Planning and Diagnostic Radiology.

Stereotactic body radiation therapy (SBRT) is commonly used to treat early-stage non-small cell lung cancer. Beam arrangements for SBRT include multiple entry and exit pathways resulting in irregular low-dose distributions within normal lung parenchyma. An improved understanding of posttreatment radiographic changes may improve the ability to predict clinical complications including radiation pneumonitis as well as assist in early detection of local failures. Radiation treatment planning is conducted using software systems separate from diagnostic radiology, often not accessible to the diagnostic radiologist. We developed a workflow for interfacing radiation dose information from lung SBRT treatments with a diagnostic radiology picture archiving and communication system (PACS). In an anonymized PACS study folder, SBRT dose maps depicting high-dose, low-dose, and nonirradiated lung volumes were viewable side by side with pretreatment and follow-up diagnostic computed tomography scans. Clinical utility was evaluated by 2 thoracic diagnostic radiologists reviewing posttreatment diagnostic follow-up scans in the PACS both with and without radiation dose maps available. The addition of the biologically effective dose map did not significantly change identification rates of radiation induced lung injury) (92% vs 95%; P = .32) but did significantly decrease radiologic suspicion for local recurrence (22% vs 8%; P = .003). The addition of biologically effective dose maps significantly increased confidence in identifying radiation induced lung injury (7.75 vs 8.82; P = .004) and local recurrence (5.5 vs 6.6; P = .005). The recommendation for additional workup was not significantly different (10% vs 7%; P = .41). We demonstrated the feasibility and clinical utility of a workflow generating simplified radiation dose maps that are viewable within a PACS for diagnostic radiology review.

Worsening Racial Disparities in Utilization of Intensity Modulated Radiation Therapy.

Purpose: The benefits of intensity modulated radiation therapy (IMRT) compared with standard 3-dimensional conformal radiation therapy have been demonstrated in many cancer sites and include decreased acute and late toxicity, improved quality of life, and opportunities for dose escalation. Limited literature suggests non-white patients may have lower utilization of IMRT. We hypothesized that as the use of IMRT has increased in recent years, racial inequities have persisted and disproportionately affect non-Hispanic Black (NHB) patients. We aim to evaluate temporal trends in IMRT utilization focusing on disparities among minoritized populations. Methods and Materials: The National Cancer Database was queried to identify the 10 disease sites with the highest total number of cancer patients treated with definitive intent IMRT in 2017, the most recent year for which data are available. Exclusions included stage IV, age <18 years, unknown insurance status, unknown race, and palliative intent radiation. Race and ethnicity variables were combined and classified as non-Hispanic White, Hispanic, NHB, Asian, Native American/Eskimo, and Hawaiian/Pacific Islander. Multivariable logistic regression for IMRT utilization was performed for each disease site for both early (2004-2010) and contemporary (2011-2017) cohorts, adjusting for clinical and demographic covariates. Results: Among the 10 selected disease sites, 1,010,292 patients received radiation therapy as part of definitive treatment between 2004 and 2017. Overall IMRT utilization rates increased from 22.0% in 2004 to 57.8% in 2017. After adjustment and compared with non-Hispanic White patients, NHB patients were significantly less likely to receive IMRT in 1 of 10 disease sites in the 2004 to 2010 cohort, and 5 of 10 disease sites in the 2011 to 2017 cohort. Conclusions: Despite greater awareness of racial disparities in cancer care and outcomes, this study demonstrates worsening disparities in the use of IMRT, particularly for NHB patients. These differences may exacerbate racial disparities in cancer outcomes; therefore, identification of underlying drivers of differential IMRT utilization is warranted.

Racial and Ethnic Health Disparities in Delay to Initiation of Intensity-Modulated Radiotherapy.

PURPOSE: Delays in initiation of radiotherapy may contribute to inferior oncologic outcomes that are more commonly observed in minoritized populations in the United States. We aimed to examine inequities associated with delayed initiation of intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS: The National Cancer Database was queried to identify the 10 cancer sites most commonly treated with IMRT. Interval to initiation of treatment (IIT) was broken into quartiles for each disease site, with the 4th quartile classified as delayed. Multivariable logistic regression for delayed IIT was performed for each disease site using clinical and demographic covariates. Differences in magnitude of delay between subsets of patients stratified by race and insurance status were evaluated using two-sample t-tests. RESULTS: Among patients (n = 350,425) treated with IMRT between 2004 and 2017, non-Hispanic Black (NHB), Hispanic, and Asian patients were significantly more likely to have delayed IIT with IMRT for nearly all disease sites compared with non-Hispanic White (NHW) patients. NHB, Hispanic, and Asian patients had significantly longer median IIT than NHW patients (NHB 87 days, P < .01; Hispanic 76 days, P < .01; Asian 74 days, P < .01; and NHW 67 days). NHW, Hispanic, and Asian patients with private insurance had shorter median IIT than those with Medicare (P < .01); however, NHB patients with private insurance had longer IIT than those with Medicare (P < .01). CONCLUSION: Delays in initiation of IMRT in NHB, Hispanic, and Asian patients may contribute to the known differences in cancer outcomes and warrant further investigation, particularly to further clarify the role of different insurance policies in delays in advanced modality radiotherapy.

The Clinical Significance of Maximum Tumor Diameter on MRI in Men Undergoing Radical Prostatectomy or Definitive Radiotherapy for Locoregional Prostate Cancer.

INTRODUCTION: Maximum tumor diameter (MTD) on pretreatment magnetic resonance imaging (MRI) has the potential to further risk stratify for men with prostate cancer (PCa) prior to definitive local therapy. We aim to evaluate the prognostic impact of radiographic maximum tumor diameter (MTD) in men with localized prostate cancer. PATIENTS AND METHODS: From a single-center retrospective cohort of men receiving definitive treatment for PCa (radical prostatectomy [RP] or radiotherapy [RT]) with available pretreatment MRI, we conducted univariable and multivariable Cox proportional-hazards models for progression using clinical variables including age, NCCN risk group, radiographic extracapsular extension (ECE), radiographic seminal vesical invasion (SVI), and MTD. RP and RT cohorts were analyzed separately. Covariates were used in a classification and regression tree (CART) analysis and progression-free survival was estimated with the Kaplan-Meier method and groups were compared using log-rank tests. RESULTS: The cohort included 631 patients (n = 428 RP, n = 203 RT). CART analysis identified 4 prognostic groups for patients treated with RP and 2 prognostic groups in those treated with RT. In the RP cohort, NCCN low/intermediate risk group patients with MTD>=15 mm had significantly worse PFS than those with MTD <= 14 mm, and NCCN high-risk patients with radiographic ECE had significantly worse PFS than those without ECE. In the RT cohort, PFS was significantly worse in the cohort with MTD >= 23 mm than those <= 22 mm. CONCLUSION: Radiographic MTD may be a useful prognostic factor for patients with locoregional prostate cancer. This is the first study to illustrate that the importance of pretreatment tumor size may vary based on treatment modality.

Initial experience and clinical comparison of two image guidance methods for SBRT treatment: 4DCT versus respiratory-triggered imaging.

For Stereotactic Body Radiation Therapy (SBRT) treatment of lung and liver, we quantified the differences between two image guidance methods: 4DCT and ExacTrac respiratory-triggered imaging. Five different patients with five liver lesions and one lung lesion for a total of 19 SBRT delivered fractions were studied. For the 4DCT method, a manual registration process was used between the 4DCT image sets from initial simulation and treatment day to determine the required daily image-guided corrections. We also used the ExacTrac respiratory-triggered imaging capability to verify the target positioning, and calculated the differences in image guidance shifts between these two methods. The mean (standard deviation) of the observed differences in image-guided shifts between 4DCT and ExacTrac respiratory-triggered image guidance was left/right (L/R) = 0.4 (2.0) mm, anterior/posterior (A/P) = 1.4 (1.7) mm, superior/inferior (S/I) = 2.2 (2.0) mm, with no difference larger than 5.0 mm in any given direction for any individual case. The largest error occurred in the S/I direction, with a mean of 2.2 mm for the six lesions. This seems reasonable, because respiratory motion and the resulting imaging uncertainties are most pronounced in this S/I direction. Image guidance shifts derived from ExacTrac triggered imaging at two extreme breathing phases (i.e., full exhale vs. full inhale), agreed well (less than 2.0 mm) with each other. In summary, two very promising image guidance methods of 4DCT and ExacTrac respiratory-triggered imaging were presented and the image guidance shifts were comparable for the patients evaluated in this study.

Evaluation of dose distribution differences from five algorithms implemented in three commercial treatment planning systems for lung SBRT.

Early stage lung cancer is increasingly being treated using stereotactic body radiation therapy (SBRT). Several advanced treatment planning algorithms are now available in various commercial treatment planning systems. This work compares the dose distributions calculated for the same treatment plan using, five algorithms, in three different treatment planning systems. All plans were normalized to ensure the prescription dose covers 95% of the planning target volume (PTV). Dose to the planning target volume (PTV) was compared using near-minimum dose (D98%), near-maximum dose (D2%) and dose homogeneity, while dose fall-off was compared using D2cm and R50. Dose to the lung was compared using V5Gy, V20Gy and mean lung dose. Statistical analysis shows that dose distributions calculated using Eclipse's Acuros XB and RayStation's Monte Carlo were significantly different from the other dose distributions for the PTV dose parameters investigated. For lung dosimetric parameters, this difference persisted for volumetric modulated arc therapy (VMAT) plans but not for conformal arc plans. While normal tissue complication probability (NTCP) differences were significant for some of the algorithms for VMAT delivery approaches, they were not significantly different for any algorithm for conformal arc plans. All parameters investigated here were within 5% between all algorithms. The results show that, while some small dosimetric differences can be expected around the PTV, the dose distribution to the rest of the treatment area, especially the lungs, should not be clinically-relevant when switching between one of the five algorithms investigated.

Radiation therapy and secondary malignancy in Li-Fraumeni syndrome: A hereditary cancer registry study.

BACKGROUND: Li-Fraumeni Syndrome (LFS) is a rare cancer-predisposing condition caused by germline mutations in TP53. Conventional wisdom and prior work has implied an increased risk of secondary malignancy in LFS patients treated with radiation therapy (RT); however, this risk is not well-characterized. Here we describe the risk of subsequent malignancy and cancer-related death in LFS patients after undergoing RT for a first or second primary cancer. METHODS: We reviewed a multi-institutional hereditary cancer registry of patients with germline TP53 mutations who were treated from 2004 to 2017. We assessed the rate of subsequent malignancy and death in the patients who received RT (RT group) as part of their cancer treatment compared to those who did not (non-RT group). RESULTS: Forty patients with LFS were identified and 14 received RT with curative intent as part of their cancer treatment. The median time to follow-up after RT was 4.5 years. Fifty percent (7/14) of patients in the curative-intent group developed a subsequent malignancy (median time 3.5 years) compared to 46% of patients in the non-RT group (median time 5.0 years). Four of seven subsequent malignancies occurred within a prior radiation field and all shared histology with the primary cancer suggesting recurrence rather than new malignancy. CONCLUSION: We found that four of14 patients treated with RT developed in-field malignancies. All had the same histology as the primary suggesting local recurrences rather than RT-induced malignancies. We recommend that RT should be considered as part of the treatment algorithm when clinically indicated and after multidisciplinary discussion.

Comparison of transperineal ultrasound image guidance technique to transabdominal technique for prostate radiation therapy.

INTRODUCTION: Ultrasound (US) guidance of the prostate has long been conducted using a transabdominal (TA) approach. More recently, a transperineal (TP) approach has been made available for image guidance. Our aim was to determine if both methods produced similar alignments within the same patients. MATERIALS AND METHODS: We utilized two clinical US image guidance (IG) systems (Elekta Clarity and Best BAT). The B-mode Acquisition and Targeting USIG system is a bi-planar, so-called 2.5D USIG system, that is acquired TA. Clarity is a 3D US system that generates a volumetric 3D US data set and US-derived IG contours that are coregistered to the planning CT images. The probe is oriented in the sagittal plane against the perineum (TP). After positioning the patient for treatment using the TP USIG, we maintained the position defined by Clarity tracking and then acquired a TA-based USIG. The two US-based methods of localizing the prostate (TA vs TP) were compared via Bland-Altman (BA) statistical analysis to determine if there was alignment agreement between methods. RESULTS: The BA test for all 101 patients, 2093 fractions resulted in 95% confidence intervals (upper and lower limits of the BA test) of 0.6 mm in LR, 0.9 mm in AP and 1.0 mm in SI. The bias between the two systems was calculated as 0.03, 0.02, and 0.03 mm in LR, AP, and SI. CONCLUSIONS: Both systems resulted in statistically equivalent targeting positions for the prostate. Because of the unique intrafraction, real-time motion tracking capability of the TP system, this solution represents a unique extension to the previously reported clinical benefits of a TA approach by providing assurance of the prostate remaining in the treatment field during beam-on.

Preliminary clinical experience with Calypso anchored beacons for tumor tracking in lung SBRT.

PURPOSE: To present our preliminary experience with the recently released Calypso lung beacons to track lung tumor location during stereotactic body radiation therapy (SBRT). MATERIALS/METHODS: Five recent lung SBRT patients had Calypso lung beacons implanted for tumor tracking during treatment. Beacons were placed by a pulmonologist using fluoroscopic navigation within 1 week prior to planning four-dimensional computed tomography (4DCT) acquisition. Patients were immobilized in a full-body double-vacuum bag. For the first three patients, a verification 4DCT was obtained prior to the first fraction with the patient in the treatment position to assess both beacon migration and motion of tumor and beacons relative to planning day. For each treatment fraction, Calypso was used to position the patient. A verification cone-beam CT (CBCT) confirmed the Calypso-defined target position was appropriate. Real-time Calypso tracking information was also acquired and compared to an action level that was used to determine if the tumor migrated outside of the planning target volume. RESULTS: For four patients, the implant procedure was well tolerated, with average CBCT-based shifts being within 0.2 mm of the shifts reported by Calypso at the time of imaging. The other patient had a small pneumothorax due to very peripheral tumor location and experienced beacon migration. However, the patient quickly recovered from the pneumothorax, and after deactivating that beacon, motion tracking was possible throughout his treatment. CONCLUSIONS: All patients were successfully treated with SBRT using the newly released Calypso lung beacons, with initial positioning confirmed by this clinic's current clinical standard of CBCT. The system allowed us to validate, with real-time confirmation, that the planned internal target volumes were appropriate to each day's extent of actual tumor motion. An efficient and effective workflow for utilizing the new lung beacons for SBRT treatments was developed.

Metastasis, Mortality, and Quality of Life for Men With NCCN High and Very High Risk Localized Prostate Cancer After Surgical and/or Combined Modality Radiotherapy.

PURPOSE: To compare metastasis-free survival, overall survival, and patient-reported quality of life (QOL) of men with National Comprehensive Cancer Network high or very high risk prostate cancer after definitive surgery and/or multimodal radiotherapy (RT). PATIENTS AND METHODS: We studied a retrospective cohort study of 586 patients treated between the years 2000 and 2017 receiving radical prostatectomy with or without postoperative RT, external-beam RT (EBRT) with androgen deprivation therapy (ADT), or EBRT plus brachytherapy (Brachy) boost + ADT. Patient-reported QOL for urinary, bowel, sexual, and overall physical and mental functioning was assessed using the American Urological Association symptom scale, the Sexual Health Inventory in Men, the Rectal-Function Assessment Scale, the Expanded Prostate Cancer Index Composite, and the Veterans RAND 12-Item Health Survey. RESULTS: Median follow-up for survival was 5 years. No significant differences between the treatments were observed for overall survival or metastasis-free survival at the P < .05 threshold. The propensity-adjusted 5-year metastasis-free survival estimates for EBRT + ADT, EBRT + Brachy + ADT, and surgery were 74.6%, 94.8%, and 83.1%, respectively. The EBRT + Brachy + ADT and surgery cohorts had significantly worse mean American Urological Association symptom scores at 6 months than the EBRT + ADT cohort, which resolved by 1 year. Surgical patients had better rectal function scores than EBRT + ADT patients at years 1 to 3, but similar function thereafter. Adjuvant or salvage RT resulted in significant declines in various Expanded Prostate Cancer Index Composite urinary, sexual, and bowel domains, and Veterans RAND 12-Item Health Survey physical but not mental domains. CONCLUSION: Men with very and/or high-risk localized prostate cancer are likely to require multimodal therapy. The overall differences in survival and long-term QOL are similar for men choosing surgical versus RT pathways.

Patterns of Failure Observed in the 2-Step Institution Credentialing Process for NRG Oncology/Radiation Therapy Oncology Group 1005 (NCT01349322) and Lessons Learned.

PURPOSE: To investigate patterns of failure in institutional credentialing submissions to NRG/RTOG 1005 with the aim of improving the quality and consistency for future breast cancer protocols. METHODS AND MATERIALS: NRG/RTOG 1005 allowed the submission of 3-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and simultaneous integrated boost (SIB) breast plans. Credentialing required institutions to pass a 2-step quality assurance (QA) process: (1) benchmark, requiring institutions to create a plan with no unacceptable deviations and ≤1 acceptable variation among the dose volume (DV) criteria, and (2) rapid review, requiring each institution's first protocol submission to have no unacceptable deviations among the DV criteria or contours. Overall rates, number of resubmissions, and reasons for resubmission were analyzed for each QA step. RESULTS: In total, 352 institutions participated in benchmark QA and 280 patients enrolled had rapid review QA. Benchmark initial failure rates were similar for 3DCRT (18%), IMRT (17%), and SIB (18%) plans. For 3DCRT and IMRT benchmark plans, ipsilateral lung most frequently failed the DV criteria, and SIB DV failures were seen most frequently for the heart. Rapid review contour initial failures (35%) were due to target rather than organs at risk. For 29% of the rapid review initial failures, the planning target volume boost eval volume was deemed an unacceptable deviation. CONCLUSIONS: The review of the benchmark and rapid review QA submissions indicates that acceptable variations or unacceptable deviations for the ipsilateral lung and heart dose constraints were the most commonly observed cause of benchmark QA failure, and unacceptable deviations in target contouring, rather than normal structure contouring, were the most common cause of rapid review QA failure. These findings suggest that a rigorous QA process is necessary for high quality and homogeneity in radiation therapy in multi-institutional trials of breast cancer to ensure that the benefits of radiation therapy far outweigh the risks.

Stereotactic body radiotherapy versus percutaneous local tumor ablation for early-stage non-small cell lung cancer.

OBJECTIVES: To compare patterns of care and overall survival (OS) between stereotactic body radiotherapy (SBRT) and percutaneous local tumor ablation (LTA) for non-surgically managed early-stage non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: The National Cancer Database (NCDB) was queried from 2004 to 2014 for adults with non-metastatic, node-negative invasive adenocarcinoma or squamous cell carcinoma of the lung with primary tumor size ≤5.0 cm who did not undergo surgery or chemotherapy and received SBRT or LTA. Patterns of care were assessed with multivariate logistic regression. After propensity-score weighting with generalized boosted regression, OS was assessed with univariate and doubly-robust multivariate Cox regression. RESULTS: Of 15,792 patients, 14,651 (93%) received SBRT and 1141 (7%) received LTA. Increasing age (OR 1.01, p = .035), treatment at an academic institution (OR 2.94, p < .001), increasing tumor size (OR 1.05, p < .001), and more recent year of diagnosis (OR 1.43, p < .001) were predictive of treatment with SBRT, whereas comorbidities (OR 0.74, p = .003) and treatment at a high-volume facility (OR 0.05, p < .001) were predictive for LTA. At a median follow-up of 26.2 months, SBRT was associated with improved OS relative to LTA within a propensity-score weighted doubly-robust multivariate analysis (HR 0.71, p < .001). On weighted subgroup analyses, improved OS was observed with SBRT for tumor sizes >2.0 cm (HR 0.72, p < .001) and for those treated at high-volume facilities (HR 0.71, p < .001). No OS difference was found with SBRT or LTA in tumor sizes ≤2.0 cm (HR 0.90, p = .227). CONCLUSION: Within the NCDB, SBRT was more commonly utilized and was associated with improved OS when compared to percutaneous LTA for patients with non-surgically managed early-stage NSCLC. Patients with small tumor volumes likely represent an appropriate population for future prospective randomized comparisons between SBRT and LTA.

Comparison of surface guidance and target matching for image-guided accelerated partial breast irradiation (APBI).

PURPOSE: We investigate the feasibility of surface guided radiation therapy (SGRT) for accelerated partial breast irradiation (APBI) by comparing it with in-room, fan beam kV computed tomography on rails (CTOR) imaging of the targeted region. The uniqueness of our study is that all patients have multiple daily CTOR scans to compare corresponding SGRT AlignRT (VisionRT, United Kingdom) images to. METHODS/MATERIALS: Twelve patients receiving APBI were enrolled in this study. Before each treatment fraction, after patients were setup on tattoos, SGRT was performed using AlignRT, and then target matching was performance using CTOR. The average and maximum difference in shifts between SGRT and CTOR were calculated and analyzed for each patient, so as the correlation between surgical cavity size and shift difference. RESULTS: Our study showed that SGRT agreed well with CTOR for patients with small surgical cavity volume changes (<10%). There were nine patients who had a ≥5 mm maximum shift difference between SGRT and CTOR along any direction, and in two patients the difference was more than 10 mm (one patient with surgical cavity change 44.3% and one patient with 27 cc cavity volume decrease). All patients, except one, had a mean shift difference < 5 mm along any direction. CONCLUSION: For the patients studied here, SGRT appears to be a reasonable and potentially valuable image guidance approach for APBI for patients who experience small changes in surgical cavity volume (<10%) between CT simulation and treatment. However, there is potential for larger alignment errors (up to 11 mm) when using SGRT for patients who experience larger surgical cavity changes.

Sequencing of Postoperative Radiotherapy and Chemotherapy for Locally Advanced or Incompletely Resected Non-Small-Cell Lung Cancer.

Purpose Although several feasibility studies have demonstrated the safety of adjuvant concurrent chemoradiotherapy (CRT) for locally advanced or incompletely resected non-small-cell lung cancer (NSCLC), it remains uncertain whether this approach is superior to sequential chemotherapy followed by postoperative radiotherapy (C→PORT). We sought to determine the most effective treatment sequence. Patients and Methods Using the National Cancer Database, we selected two cohorts of patients with nonmetastatic NSCLC who had received at least a lobectomy followed by multiagent chemotherapy and radiotherapy; cohort one included patients with R0 resection and pN2 disease, whereas cohort two included patients with R1-2 resection regardless of nodal status. Overall survival (OS) was examined using a propensity score-matched analysis with a shared frailty Cox regression. Results A total of 747 patients in cohort one and 277 patients in cohort two were included, with a median follow-up of 32.8 and 27.9 months, respectively. The median OS was 58.8 months for patients who received C→PORT versus 40.4 months for patients who received CRT in cohort one (log-rank P < .001). For cohort two, the median OS was 42.6 months for patients who received C→PORT versus 38.5 months for patients who received CRT (log-rank P = .42). After propensity score matching, C→PORT remained associated with improved OS compared with CRT in cohort one (hazard ratio, 1.35; P = .019), and there was no statistical difference in OS between the sequencing groups for cohort two (hazard ratio, 1.35; P = .19). Conclusion Patients with NSCLC who undergo R0 resection and are found to have pN2 disease have improved outcomes when adjuvant chemotherapy is administered before, rather than concurrently with, radiotherapy. For patients with positive margins after surgery, there is not a clear association between treatment sequencing and survival.

Primary Pulmonary Carcinoid Tumor: A Long-term Single Institution Experience.

OBJECTIVES: Primary carcinoid tumors of the lung are rare tumors which comprise approximately 0.5% to 5% of all lung malignancies in adults and roughly 20% to 30% of all carcinoid tumors. The purpose of this retrospective, descriptive study was to describe the incidence, characteristics, and outcomes of patients treated for primary pulmonary carcinoid tumor at a single institution. MATERIALS AND METHODS: All patients with a diagnosis of primary pulmonary carcinoid tumor treated from 1989 to 2009 were reviewed. Data collected included demographics, pathology, tobacco use, clinical presentation, tumor location, tumor spread, treatment, and survival. RESULTS: There were 59 cases of pulmonary carcinoid tumors: 47 typical (80%) and 12 atypical (20%). All but 4 patients underwent surgery, including 54 (92%) lung-sparing resections and 1 pneumonectomy. Five of 55 patients received concurrent adjuvant chemoradiation therapy; 4 patients with atypical and 1 with typical histology. Three additional patients with atypical carcinoid were treated only with adjuvant radiotherapy, palliative radiotherapy, or palliative chemotherapy, respectively. The Kaplan-Meier 5- and 10-year overall survivals were both 80% within the entire population. In the 88% of patients who achieved complete remission, disease-free survival was 98%. A review of a large series from the literature is also presented. CONCLUSIONS: Surgical resection was primary and adequate therapy for most typical carcinoid tumors with high overall survival and disease-free survival. Adjuvant chemotherapy or radiotherapy might be considered for patients with atypical carcinoid tumors who present with adverse pathologic findings.

Skin dose estimation using virtual structures for Contura Multi-Lumen Balloon breast brachytherapy.

PURPOSE: To propose a workflow that uses ultrasound (US)-measured skin-balloon distances and virtual structure creations in the treatment planning system to evaluate the maximum skin dose for patients treated with Contura Multi-Lumen Balloon applicators. METHODS AND MATERIALS: Twenty-three patients were analyzed in this study. CT and US were used to investigate the interfractional skin-balloon distance variations. Virtual structures were created on the planning CT to predict the maximum skin doses. Fitted curves and its equation can be obtained from the skin-balloon distance vs. maximum skin dose plot using virtual structure information. The fidelity of US-measured skin distance and the skin dose prediction using virtual structures were assessed. RESULTS: The differences between CT- and US-measured skin-balloon distances values had an average of -0.5 ± 1.1 mm (95% confidence interval [CI] = -1.0 to 0.1 mm). Using virtual structure created on CT, the average difference between the predicted and the actual dose overlay maximum skin dose was -1.7% (95% CI = -3.0 to -0.4%). Furthermore, when applying the US-measured skin distance values in the virtual structure trendline equation, the differences between predicted and actual maximum skin dose had an average of 0.7 ± 6.4% (95% CI = -2.3% to 3.7%). CONCLUSIONS: It is possible to use US to observe interfraction skin-balloon distance variation to replace CT acquisition. With the proposed workflow, based on the creation of virtual structures defined on the planning CT- and US-measured skin-balloon distances, the maximum skin doses can be reasonably estimated.