Conditional Survival in Anal Carcinoma Using the National Population-Based Survey of Epidemiology and End Results Database (1988-2012).

BACKGROUND: Conditional survival can provide valuable information for both patients and healthcare providers about the changing prognosis in surviving patients over time. OBJECTIVE: This study estimated conditional survival for patients with anal cancer in the United States through analysis of a national population-based cancer registry. DESIGN: Log-rank test identified significant covariates of cause-specific survival (defined as time from diagnosis until death from anal cancer). Significant covariates were considered in the multivariable regression of cause-specific survival using Cox proportional hazards models. SETTINGS: Covariates included cancer stage and demographic variables. PATIENTS: Patients in Surveillance, Epidemiology, and End Results regions diagnosed with anal squamous cell carcinoma as their first and only cancer diagnosis from 1988 to 2012 were selected from this database, and 5145 patients were included in the retrospective cohort study. MAIN OUTCOME MEASURE: Five-year conditional survival stratified by each variable in the final Cox models was measured RESULTS: : The final multivariable models of overall and cause-specific survivals included stage, grade, sex, age, race, and relationship status. Over the first 6 years after diagnosis, conditional survival of distant stage increased from 37% to 89%, whereas regional stage increased from 65% to 93% and localized stage increased from 84% to 96%. The other variables had increasing prognosis as well, but the subgroups increased at a more similar rate over time. LIMITATIONS: The data source used does not include information on chemotherapy treatment, patient comorbidities, or socioeconomic status. CONCLUSIONS: Conditional survival showed improvement over time. Patients with advanced stage had the greatest improvement in conditional survival. This is the first study to provide specific conditional survival probabilities for patients with anal cancer.

Scholastic activity among radiation oncology residents at US academic institutions: a benchmark analysis.

Objective assessment of academic productivity is useful for residency programs. This study aims to analyze the number of publications and Hirsch index (h index) among radiation oncology residents. Names of residents during the 2010 academic year (n = 607) were collected from the Association of Residents in Radiation Oncology 2010 Directory. Number of publications and h index from Jan. 1996 to Feb. 2012 were collected from a bibliographic database (SCOPUS, Elsevier, BV, Amsterdam, NL). Analysis of h index included stratification by gender, residency size, and postresidency private practice or academic employment. Six hundred seven residents, 67% men and 33% women, had an overall mean h index of 2.5 ± 3.2. Graduates in academia exhibited a higher mean h index (3.9 ± 0.30) compared to private practice (2.0 ± 0.25; p < 0.01). Gender, residency size, and post-graduate position remained correlates of h index (all p ≤ 0.01). Women had lower mean h index and number of publications than men (2.1 ± 2.3 vs 2.7 ± 3.5, 4.5 ± 5.3 vs 6.2 ± 8.0, respectively; both p < 0.05). However, when stratified by current position (resident, private practice, or academic), there were no significant differences in h index by gender. The mean ± SD h indices for institutions comprising the top 10% ranged 4.17 ± 3.2-5.25 ± 5.4 while the bottom 10% ranged 0.0 ± 0.0-0.75 ± 1.4. The h index is a useful metric to assess residents' early dedication to scholarly endeavors. Female radiation oncology residents had fewer total publications and slightly lower h indices, warranting accessible research avenues and environments for future female physician-scientists. The application of the h index provides a reference for medical students, residents, residency program directors, and many others to gauge academic performance and establish appropriate benchmarks.

Distribution of the h-index in radiation oncology conforms to a variation of power law: implications for assessing academic productivity.

Leaders of academic institutions evaluate academic productivity when deciding to hire, promote, or award resources. This study examined the distribution of the h-index, an assessment of academic standing, among radiation oncologists. The authors collected h-indices for 826 US academic radiation oncologists from a commercial bibliographic database (SCOPUS, Elsevier B.V., NL). Then, logarithmic transformation was performed on h-indices and ranked h-indices, and results were compared to estimates of a power law distribution. The h-index frequency distribution conformed to both the log-linear variation of a power law (r (2) = .99) and the beta distribution with the same fitting exponents as previously described in a power law analysis of the productivity of neurosurgeons. Within radiation oncology, as in neurosurgery, there are exceedingly more faculty with an h-index of 1-2. The distribution fitting the same variation of a power law within two fields suggests applicability to other areas of academia.

Safety and patterns of survivorship in recurrent GBM following resection and surgically targeted radiation therapy: Results from a prospective trial.

BACKGROUND: Treatment of recurrent glioblastoma (GBM) remains problematic with survival after additional therapy typically less than 12 months. We prospectively evaluated whether outcomes might be improved with resection plus permanent implantation of a novel radiation device utilizing the gamma-emitting isotope Cs-131 embedded within bioresorbable collagen tiles. METHODS: Recurrent histologic GBM were treated in a single-arm trial. Following radiation, the surgical bed was lined with the tiles. Subsequent treatments were at the treating physician's discretion. RESULTS: 28 patients were treated (20 at first recurrence, range 1-3). Median age was 58 years, KPS was 80, female:male ratio was 10:18. Methylguanine methyltransferase (MGMT) was methylated in 11%, unmethylated in 18%, and unknown in 71%. Post implant, 17 patients (61%) received ≥1 course of systemic therapy. For all patients, Kaplan-Meier estimates of median time to local failure were 12.1 months, post-implant survival was 10.7 months for all patients and 15.1 months for patients who received systemic therapy; for all patients, median overall survival from diagnosis was 25.0 months (range 9.1-143.1). Sex, age, and number of prior progressions were not statistically significant. Local control was continuously maintained in 46% of patients. Two deaths within 30 days occurred, one from intracranial hemorrhage and one after persistent coma. Three symptomatic adverse events occurred: one wound infection requiring surgery and two late radiation brain injury, resolved non-surgically. CONCLUSION: This pre-commercial trial demonstrated acceptable safety and favorable post-treatment local control and survival. The device has received FDA clearance for use in newly diagnosed malignant and all recurrent intracranial neoplasms.

Technological advances in radiation therapy for prostate cancer.

Radiation therapy (RT) for prostate cancer has made huge strides over the past two decades. The addition of image guidance has allowed radiation oncologists to ensure accurate delivery of increasingly precise radiation treatment plans using newer conformal therapy methods such as three-dimensional conformal RT, intensity-modulated RT, and proton beam RT. Regardless of the specific treatment technique, patients can depend on the treatment to target the moving prostate effectively while significantly sparing adjacent tissues, thereby reducing the morbidity of having to undergo prostate cancer therapy. This review summarizes the recent technical advances made in radiation dose delivery, including target volume definition, treatment planning, treatment delivery methods, and positional verification methods during RT.

Re-Irradiation Using Brachytherapy for Recurrent Intracranial Tumors: A Systematic Review and Meta-Analysis of the Literature.

Introduction We aim to compare the efficacy and toxicity of re-irradiation using brachytherapy for patients with locally recurrent brain tumors after previous radiation therapy.  Methods We performed a systematic review of the major biomedical databases from 2005 to 2020 for eligible studies where patients were treated with re-irradiation for recurrent same site tumors using brachytherapy. Tumor types included high-grade gliomas (HGG) (World Health Organization (WHO) Grades 3 and 4), meningiomas, and metastases. The outcomes of interest were median overall survival (OS) and progression-free survival (PFS) after re-irradiation, the incidence of radiation necrosis (RN), and other relevant radiation-related adverse events (AE). We used a fixed-effect meta-analysis regression moderation model to compared results of interstitial versus intracavitary therapy, treatment with low-dose-rate (LDR) versus high-dose-rate (HDR) techniques, and outcomes by tumor type. Results The search resulted in a total of 194 articles. A total of 16 articles with 695 patients fulfilled the inclusion criteria and were selected for analysis. For high-grade glioma, meningioma, and brain metastasis the pooled meta-analysis showed mean symptomatic RN rates of 3.3% (standard error (SE) = 0.8%), 17.3% (SE = 5.0%), and 22.4% (SE = 7.0%), respectively, and mean rates of RN requiring surgical intervention of 3.0% (SE = 1.0%), 11.9% (SE = 5.3%), and 10.0% (SE = 7.3%), respectively. The mean symptomatic RN rates in the meta-analysis comparing interstitial versus intracavitary therapy were 3.4% and 4.9%, respectively (p = 0.36), and for the comparison of LDR versus HDR, the rates were 2.6% and 5.7%, respectively (p = 0.046). In comparing the symptomatic RN rates in comparison to HGG versus meningioma, the means were 3.3% and 17.3%, respectively (p = 0.006), and in HGG versus metastatic tumors, the means were 3.3% and 22.4%, respectively (p = 0.007). There was no significant difference in rates of RN requiring surgery in any of these groups. Due to the small number of studies and inconsistent recording of OS and PFS, statistical analysis of these parameters could not be performed. Conclusion Published literature on the same site re-irradiation using brachytherapy for recurrent brain tumors is highly limited, with inconsistent reporting of safety and efficacy outcomes. To overcome these shortcomings, we utilized a structured meta-analysis approach to show that re-irradiation with modern brachytherapy is generally safe in terms of the risks of symptomatic RN. We also found that symptomatic RN rates for brachytherapy are significantly lower in recurrent HGG compared to recurrent meningiomas (p = 0.006) and metastatic tumors (p = 0.007). Re-irradiation with brachytherapy is a feasible option for appropriately selected patients. The availability of Cesium-131 (Cs-131) shows promise in reducing toxicity while achieving excellent local control due to its physical properties, and the recent introduction of a novel surgically targeted radiation therapy device, that makes brachytherapy less technically demanding, may allow for more widespread adoption. Prospective trials with consistent reporting of endpoints are needed to explore whether these advances improve safety and efficacy in patients with recurrent, previously irradiated tumors.

Relative lack of conditional survival improvement in young adults with cancer.

Cancer prognosis is usually reported in terms of survival from time of diagnosis. For patients surviving a period of time after diagnosis, conditional survival (CS) accounts for changing risk over time. This report provides information on how CS in cancer patients changes as a function of age at diagnosis. Using data from the US Surveillance, Epidemiology and End Results database, we examined survival for patients diagnosed between 1973 and 2002. The average annual percent change (AAPC) in CS during the first 5 years after diagnosis was evaluated for the 14 most common cancers occurring in young adults, defined as 15- to 39-year-olds, and how they compared with cancers that are more common in older and younger patients. For all cancers, young adult patients had less CS improvement over time than younger or older patients, and this difference was most pronounced in those aged 20 to 29 years (45% below the mean). Eleven of the 14 most common cancers in 15- to 39-year-olds either had a lower CS improvement after diagnosis than either younger or older patients, or than just the older patients. Young adults with leukemia had the greatest improvement in CS over time. In conclusion, young adults with cancer have not enjoyed the same improvement in CS over time compared with other age groups. Explanations for this deficit include the biologic nature of the type of cancers in young adults and less effective therapies for patients in the age group. Regardless of the reasons, the deficit is yet another challenge faced by young adult patients that merits further study.

Effect of body mass index on shifts in ultrasound-based image-guided intensity-modulated radiation therapy for abdominal malignancies.

BACKGROUND AND PURPOSE: We investigated whether corrective shifts determined by daily ultrasound-based image-guidance correlate with body mass index (BMI) of patients treated with image-guided intensity-modulated radiation therapy (IG-IMRT) for abdominal malignancies. The utility of daily image-guidance, particularly for patients with BMI>25.0, is examined. MATERIALS AND METHODS: Total 3162 ultrasound-directed shifts were performed in 86 patients. Direction and magnitude of shifts were correlated with pretreatment BMI. Bivariate statistical analysis and analysis of set-up correction data were performed using systematic and random error calculations. RESULTS: Total 2040 daily alignments were performed. Average 3D vector of set-up correction for all patients was 12.1mm/fraction. Directional and absolute shifts and 3D vector length were significantly different between BMI cohorts. 3D displacement averaged 4.9 mm/fraction and 6.8mm/fraction for BMI < or = 25.0 and BMI>25.0, respectively. Systematic error in all axes and 3D vector was significantly greater for BMI>25.0. Differences in random error were not statistically significant. CONCLUSIONS: Set-up corrections derived from daily ultrasound-based IG-IMRT of abdominal tumors correlated with BMI. Daily image-guidance may improve precision of IMRT delivery with benefits assessed for the entire population, particularly patients with increased habitus. Requisite PTV margins suggested in the absence of daily image-guidance are significantly greater in patients with BMI>25.0.

Increased vulnerability of the spinal cord to radiation or intrathecal chemotherapy during adolescence: A report from the Children's Oncology Group.

PURPOSE: To assess the rate of spinal cord toxicity in adolescents resulting from chemoradiotherapy of parameningeal sarcoma. METHODS AND MATERIALS: Of 152 patients with parameningeal sarcoma treated per the Intergroup Rhabdomyosarcoma Study Group protocol from 1977 through 1989, eight developed paralyzing ascending myelitis after intrathecal chemotherapy with cytosine arabinoside, methotrexate, and hydrocortisone administered during and after radiation therapy to volumes that included part of the spinal cord. The eight cases include three not previously published. RESULTS: Of eight patients who developed CNS toxicity after intrathecal chemotherapy and radiotherapy for parameningeal rhabdomyosarcoma, all but one were between 13 and 18 years of age when treated. This severe toxicity occurred in one quarter of 28 adolescents treated with the regimen in comparison with one of 123 children 12 years of age or less (P < 0.0001), a rate that was as much as 30 times higher in the adolescents. Lengthening of the spinal cord during the pubertal growth spurt may account for the apparent increased vulnerability. CONCLUSIONS: Chemoradiotoxicity-associated spinal cord injury appears to be more likely to occur in adolescents than in younger or older ages. This observation appears to reverse a conventional wisdom in which the central nervous system is thought to become more resistant to the neurotoxic effects of chemoradiotherapy as it matures.

National Cancer Database Analysis of the effect of brachytherapy on overall survival in patients with base of tongue cancer.

BACKGROUND: We performed an analysis of the National Cancer Database (NCDB) to evaluate overall survival (OS) in patients with base of tongue (BOT) cancer treated with external beam radiation therapy (EBRT) combined with brachytherapy (BT). METHODS: The tongue NCDB Participant User File was used to obtain demographic and clinical patient data. The Kaplan-Meier method was used to determine OS. Significance was determined using univariable and multivariable Cox proportional hazards models. RESULTS: At 3 years, OS was 69.6%, 77.1%, and 63.7% for patients treated with EBRT (n = 27 954), EBRT + BT (n = 209), or BT alone (n = 154), respectively (P = .01). On multivariable analysis, the instantaneous hazard of death for patients receiving EBRT + BT was 25% (Hazard ratio [HR] = 0.75, 95% CI: 0.58-0.98) lower than patients receiving only EBRT (P = .03). CONCLUSIONS: The addition of BT to EBRT in BOT cancer has an OS benefit.

Dose-volume relationship for laryngeal substructures and aspiration in patients with locally advanced head-and-neck cancer.

BACKGROUND: Literature has shown a significant relationship between radiation dose to the larynx and swallowing disorders. We prospectively studied the dose-volume relationship for larynx substructures and aspiration. METHODS: Forty nine patients with stage III/IV head-and-neck (H&N) squamous cell carcinoma were prospectively enrolled in this IRB-approved, federally funded study. All patients received IMRT-based chemoradiation therapy (CRT) and were scheduled for videofluorography (VFG) prior to CRT and at 3, 6, 9, 12, and 24 months post-CRT. Twelve laryngeal substructures were contoured in each patient: thyroid cartilage, cricoid cartilage, total epiglottis, suprahyoid epiglottis, infrahyoid epiglottis, total larynx, supraglottic larynx, subglottic larynx, glottic larynx, arytenoids, aryepiglottic (AE) folds, and glossoepiglottic fold. After exclusions, 29 patients were included in the final analysis. Incidence of aspiration at 1 year following CRT was correlated with dose-volume data to laryngeal substructures using logistic regression. RESULTS: The median age was 54 years with 79% being non-smokers. Tumor sites included oropharynx (22), unknown primary (6), and hypopharynx (1). One year following CRT, 10/29 (34%) showed aspiration on VFG. Dose to the AE folds showed the highest correlation with aspiration at 12 months and was significant on multivariate analysis (p = 0.025). A mean dose cutpoint of 6500 cGy or higher to the AE folds was associated with an increased risk of aspiration at 1 year [positive likelihood ratio (+LR) 2.81, positive predictive value (PPV) 60%, negative predictive value (NPV) 92.9%, relative risk (RR) 8.4]. CONCLUSIONS: In this analysis, mean dose to the AE folds was associated with an increased risk of aspiration at 1 year. However, these are hypothesis-generating data that require further research and validation in a larger patient subset.

Industry Funding Is Correlated With Publication Productivity of US Academic Radiation Oncologists.

PURPOSE: Industry payments to physicians are financial conflicts of interest and may influence research findings and medical decisions. We aim to (1) characterize industry payments within radiation oncology; and (2) explore the potential correlation between receiving disclosed industry payments and academic productivity. MATERIALS/METHODS: CMS database was used to extract 2015 industry payments. For academic radiation oncologists, research productivity was characterized by h- and m-indices, as well as receipt of National Institutes of Health (NIH) funding, which is not an industry payment. Logistic regression models were used to determine whether publication metrics (m-index, h-index) and other study characteristics such as gender, PhD status, NIH institution funding status, were associated with the endpoints, research and general payments. Associations between the amount of payments (if any) and publication metrics were further studied using linear regression models. RESULTS: A total of 22,543 individual payments totaling $25,532,482 to 2,995 radiation oncologists were included. Among the 1,189 academic radiation oncologists, 75% received less than $167; on the other hand, 10 (<1%) individuals received $6,425,728 (51%) of payments. On multiple logistic regression, research payments were significantly associated with the m-index, odds ratio 2.86 (95% confidence interval, 1.84-4.45, p-value <0.0001); as well as with the h-index, odds ratio 1.03 (95% confidence interval, 1.01-1.05, p-value <0.0001). The linear regression model shows that both m-index and h-index were significantly positively associated with the amount of general payments (p-values <0.0001). CONCLUSION: There is an association between disclosed payment from the industry and increased individual research productivity metrics. Further research to find the cause behind this association is warranted.

An in-silico quality assurance study of contouring target volumes in thoracic tumors within a cooperative group setting.

INTRODUCTION: Target delineation variability is a significant technical impediment in multi-institutional trials which employ intensity modulated radiotherapy (IMRT), as there is a real potential for clinically meaningful variances that can impact the outcomes in clinical trials. The goal of this study is to determine the variability of target delineation among participants from different institutions as part of Southwest Oncology Group (SWOG) Radiotherapy Committee's multi-institutional in-silico quality assurance study in patients with Pancoast tumors as a "dry run" for trial implementation. METHODS: CT simulation scans were acquired from four patients with Pancoast tumor. Two patients had simulation 4D-CT and FDG-FDG PET-CT while two patients had 3D-CT and FDG-FDG PET-CT. Seventeen SWOG-affiliated physicians independently delineated target volumes defined as gross primary and nodal tumor volumes (GTV_P & GTV_N), clinical target volume (CTV), and planning target volume (PTV).Six board-certified thoracic radiation oncologists were designated as the 'Experts' for this study. Their delineations were used to create a simultaneous truth and performance level estimation (STAPLE) contours using ADMIRE software (Elekta AB, Sweden 2017). Individual participants' contours were then compared with Experts' STAPLE contours. RESULTS: When compared to the Experts' STAPLE, GTV_P had the best agreement among all participants, while GTV_N showed the lowest agreement among all participants. There were no statistically significant differences in all studied parameters for all TVs for cases with 4D-CT versus cases with 3D-CT simulation scans. CONCLUSIONS: High degree of inter-observer variation was noted for all target volume except for GTV_P, unveiling potentials for protocol modification for subsequent clinically meaningful improvement in target definition. Various similarity indices exist that can be used to guide multi-institutional radiotherapy delineation QA credentialing.

Conditional survival in ovarian cancer: results from the SEER dataset 1988-2001.

OBJECTIVES: Survival statistics for patients with ovarian cancer are typically reported in terms of survival from time of diagnosis. For patients who have survived a period of time since diagnosis, however, conditional survival (CS) is a more clinically relevant measure, as it accounts for the changes in risk over time. The purpose of this study was to estimate CS for ovarian cancer patients through analysis of large-scale cancer registry data. METHODS: Ovarian cancer cases were extracted from the Surveillance, Epidemiology, and End Results (SEER 17) database from the National Cancer Institute (NCI) for patients diagnosed between 1988-2001. Five-year relative CS calculations were performed with stratification by age, race, stage, histology, and grade for patients who had already survived up to 5 years from diagnosis. RESULTS: The 5-year overall relative CS improved over time for up to 5 years after diagnosis for ovarian cancer patients. The largest gains in CS over time were seen for patients with advanced stage disease, poor grade, and serous and undifferentiated epithelioid histologies. For patients with stage IV disease, 5-year CS more than tripled over the first 5 years of surveillance (17%-56%). Among histological types, patients with undifferentiated epithelioid histology saw 5-year CS rise from 29% at diagnosis to 84% after 5 years. CONCLUSIONS: Prognosis improves over time for almost all groups of ovarian cancer patients. For ovarian cancer survivors, CS provides a more relevant measure of prognosis than conventional survival estimates that are made at the time of diagnosis.

Intensity-modulated Radiosurgery for patients with brain metastases: a mature outcomes analysis.

The purpose of this study was to evaluate the outcomes of patients with brain metastases treated by tomotherapeutic Intensity-modulated Radiosurgery (IMRS). Using retrospective chart review, we analyzed the outcomes of 78 patients (age 33-83 years, median 57 years) who underwent 111 sessions of IMRS (1 to 7 sessions per patient, median 1) for brain metastases (1 to 4 targets per IMRS session, median 1) treated between 2000 and 2005 using a serial tomotherapeutic intensity-modulated radiotherapy treatment (IMRT) planning and delivery system (Peacock, Nomos Corp., Cranberry Township, PA). Treatment planning was performed using an inverse treatment planning optimization algorithm that was optimized for IMRS. A median prescription dose of 15 Gy in combination with WBI, and median 20 Gy for IMRS alone was delivered using 2-4 couch angles over 4-24 rotational arcs. Overall survival was calculated using Kaplan-Meier analysis. To determine the effects of prognostic variables on survival, univariate and multivariate analyses using proportional hazards were performed to assess the effects of age, tumor size, the combination with whole brain irradiation, presence of multiple brain metastases, and presence of extracranial disease. The median overall survival was 6.5 months (95% CI, 5.5-7.9). One- and two-year survival rates were 24% and 10%. In multivariate analyses, age greater than 60 years was the only statistically significant variable that affected survival (hazard rate 1.29, p=0.049). We conclude that tomotherapeutic IMRS is safe and effective to treat patients with brain metastases.

Clinical Application of a Hybrid RapidArc Radiotherapy Technique for Locally Advanced Lung Cancer.

OBJECTIVE: Radiation treatment planning for locally advanced lung cancer can be technically challenging, as delivery of ≥60 Gy to large volumes with concurrent chemotherapy is often associated with significant risk of normal tissue toxicity. We clinically implemented a novel hybrid RapidArc technique in patients with lung cancer and compared these plans with 3-dimensional conformal radiotherapy and RapidArc-only plans. MATERIALS/METHODS: Hybrid RapidArc was used to treat 11 patients with locally advanced lung cancer having bulky mediastinal adenopathy. All 11 patients received concurrent chemotherapy. All underwent a 4-dimensional computed tomography planning scan. Hybrid RapidArc plans concurrently combined static (60%) and RapidArc (40%) beams. All cases were replanned using 3- to 5-field 3-dimensional conformal radiotherapy and RapidArc technique as controls. RESULTS: Significant reductions in dose were observed in hybrid RapidArc plans compared to 3-dimensional conformal radiotherapy plans for total lung V20 and mean (-2% and -0.6 Gy); contralateral lung mean (-2.92 Gy); and esophagus V60 and mean (-16.0% and -2.2 Gy; all P < .05). Contralateral lung doses were significantly lower for hybrid RapidArc plans compared to RapidArc-only plans (all P < .05). Compared to 3-dimensional conformal radiotherapy, heart V60 and mean dose were significantly improved with hybrid RapidArc (3% vs 5%, P = .04 and 16.32 Gy vs 16.65 Gy, P = .03). However, heart V40 and V45 and maximum spinal cord dose were significantly lower with RapidArc plans compared to hybrid RapidArc plans. Conformity and homogeneity were significantly better with hybrid RapidArc plans compared to 3-dimensional conformal radiotherapy plans ( P < .05). Treatment was well tolerated, with no grade 3+ toxicities. CONCLUSION: To our knowledge, this is the first report on the clinical application of hybrid RapidArc in patients with locally advanced lung cancer. Hybrid RapidArc permitted safe delivery of 60 to 66 Gy to large lung tumors with concurrent chemotherapy and demonstrated advantages for reduction in low-dose lung volumes, esophageal dose, and mean heart dose.

Adaptive Radiotherapy for Head and Neck Cancer.

OBJECTIVE: To investigate the effects of adaptive radiotherapy on dosimetric, clinical, and toxicity outcomes for patients with head and neck cancer undergoing chemoradiotherapy with intensity-modulated radiotherapy. METHODS: Fifty-one patients with advanced head and neck cancer underwent definitive chemoradiotherapy with the original plan optimized to deliver 70.2 Gy. All patients were resimulated at a median dose of 37.8 Gy (range, 27.0-48.6 Gy) due to changes in tumor volume and/or patient weight loss (>15% from baseline). Thirty-four patients underwent adaptive replanning for their boost planning (21.6 Gy). The dosimetric effects of the adaptive plan were compared to the original plan and the original plan copied on rescan computed tomography. Acute and late toxicities and tumor local control were assessed. Gross tumor volume reduction rate was calculated. RESULTS: With adaptive replanning, the maximum dose to the spinal cord, brain stem, mean ipsilateral, and contralateral parotid had a median reduction of -4.5%, -3.0%, -6.2%, and -2.5%, respectively (median of 34 patients). Median gross tumor volume and boost planning target volume coverage improved by 0.8% and 0.5%, respectively. With a median follow-up time of 17.6 months, median disease-free survival and overall survival was 14.8 and 21.1 months, respectively. Median tumor volume reduction rate was 35.2%. For patients with tumor volume reduction rate ≤35.2%, median disease-free survival was 8.7 months, whereas it was 16.9 months for tumor volume reduction rate >35.2%. Four patients had residual disease after chemoradiotherapy, whereas 64.7% (20 of 34) of patients achieved locoregional control. CONCLUSION: Implementation of adaptive radiotherapy in head and neck cancer offers benefits including improvement in tumor coverage and decrease in dose to organs at risk. The tumor volume reduction rate during treatment was significantly correlated with disease-free survival and overall survival.

Factors associated with increased academic productivity among US academic radiation oncology faculty.

OBJECTIVES: Publication productivity metrics can help evaluate academic faculty for hiring, promotion, grants, and awards; however, limited benchmarking data exist, which makes intra- and interdepartmental comparisons difficult. Therefore, we sought to evaluate the scholarly activity of physician faculty at academic radiation oncology (RO) departments and establish factors associated with increased academic productivity. METHODS AND MATERIALS: Citation database searches were performed for all physician-faculty in US residency-affiliated academic RO departments. Demographics, National Institutes of Health (NIH) funding, and bibliometrics (number of publications, Hirsch-[h]-index, and m-index [Hirsch index divided by the number of years since first publication]) were collected and stratified by academic rank. Senior academic rank was defined as full professor, professor, and/or chair. Junior academic rank was defined as all others. Logistic regression was performed to determine the association of academic rank and other factors with h- and m-indices. RESULTS: A total of 1191 academic RO physician faculty from 75 institutions were included in the analysis. The mean (standard deviation) number of publications and h- and m-indices were 48.2 (71.2), 14.5 (15), and 0.86 (0.83), respectively. The median (interquartile range) number of publications and h- and m-indices were 20 (6-61), 9 (4-20), and 0.69 (0.38-1.10), respectively. Recursive partitioning analysis revealed a statistically significant numeric h-index threshold of 21 between junior and senior faculty (LogWorth 114; receiver operating characteristic, 0.828). Senior faculty status, receipt of NIH funding, and a larger department size were associated with increased h- and m-indices. CONCLUSIONS: Current academic RO departments have relatively high objective metrics of scholastic productivity compared with prior benchmarking analyses of RO departments and compared with published metrics from other academic medicine subspecialties. An h-index of 21 or greater was associated with senior faculty status. Additionally, receipt of NIH funding and greater departmental size were associated with a higher h-index. These data may be of interest to faculty preparing for promotion or award applications as well as institutional leadership evaluating their departments.

Evaluation of Deformable Image Registration-Based Contour Propagation From Planning CT to Cone-Beam CT.

PURPOSE: We evaluated the performance of organ contour propagation from a planning computed tomography to cone-beam computed tomography with deformable image registration by comparing contours to manual contouring. MATERIALS AND METHODS: Sixteen patients were retrospectively identified based on showing considerable physical change throughout the course of treatment. Multiple organs in the 3 regions (head and neck, prostate, and pancreas) were evaluated. A cone-beam computed tomography from the end of treatment was registered to the planning computed tomography using rigid registration, followed by deformable image registration. The contours were copied on cone-beam computed tomography image sets using rigid registration and modified by 2 radiation oncologists. Contours were compared using Dice similarity coefficient, mean surface distance, and Hausdorff distance. RESULTS: The mean physician-to-physician Dice similarity coefficient for all organs was 0.90. When compared to each physician's contours, the overall mean for rigid was 0.76 (P < .001), and it was improved to 0.79 (P < .001) for deformable image registration. Comparing deformable image registration to physicians resulted in a mean Dice similarity coefficient of 0.77, 0.74, and 0.84 for head and neck, prostate, and pancreas groups, respectively; whereas, the physician-to-physician mean agreement for these sites was 0.87, 0.90, and 0.93 (P < .001, for all sites). The mean surface distance for physician-to-physician contours was 1.01 mm, compared to 2.58 mm for rigid-to-physician contours and 2.24 mm for deformable image registration-to-physician contours. The mean physician-to-physician Hausdorff distance was 11.32 mm, and when compared to any physician's contours, the mean for rigid and deformable image registration was 12.1 mm and 12.0 mm (P < .001), respectively. CONCLUSION: The physicians had a high level of agreement via the 3 metrics; however, deformable image registration fell short of this level of agreement. The automatic workflows using deformable image registration to deform contours to cone-beam computed tomography to evaluate the changes during treatment should be used with caution.

Routine use of preoperative breast MRI for patients considered for intraoperative radiotherapy.

This editorial comments on the study by Tallet et al. which reported on the incidence of ipsilateral second breast cancers (BC) detected by preoperative magnetic resonance imaging (MRI) in patients being considered for intraoperative radiotherapy (IORT). Any second BC was detected in 7% of patients; an ipsilateral BC was detected in 4% of patients, precluding them from IORT. The authors comment that in view of detection of a substantial rate of ipsilateral BCs by preoperative MRI, this exam should be used routinely for staging patients being considered for IORT.