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The sole benefit of internal mammary area irradiation (IMNI) on treatment outcome is unknown. We examined whether the inclusion of IMNI in regional nodal irradiation improved outcomes in women with node-positive breast cancer. Materials/Methods: KROG 08-06 is a multicenter, prospective, randomized phase 3 trial done at 13 hospitals in South Korea. Patients with pathologically confirmed node-positive breast cancer after breast conservation surgery (BCS) or mastectomy with axillary lymph node dissection were eligible. Patients with distant metastasis or those who had neoadjuvant treatment were excluded. All patients underwent regional nodal irradiation along with breast or chest wall irradiation using 3-dimensional conformal radiotherapy with a total dose of 45−54 Gy and fractional dose of 1.8−2.0 Gy. Patients were stratified according to the type of surgery (BCS or mastectomy) and N stage (N1 or N2, N3) and randomly allocated to either IMNI or no IMNI. The primary endpoint was 7-year disease-free survival (DFS). Secondary endpoints were rates of overall survival, breast cancer-specific survival, and toxicity. Results: Between 2008 and 2013, 747 patients were enrolled, of whom 362 patients in IMNI arm and 373 patients in non-IMNI arm were analyzed. Nearly all patients underwent taxane-based adjuvant systemic treatment. At a median follow-up of 8.4 years, 127 patients had breast cancerrelated events and 89 patients died. At 7 years, the DFS rates were 81.9% in non-IMNI arm and 85.3% in IMNI arm (HR, 0.80; 95% CI, 0.57−1.14; P = .220). Subgroup analyses showed significantly improved DFS and breast cancer mortality in IMNI arm among the patients with medio-centrally located tumors. In this subgroup, the 7-year DFS rates were 81.6% without IMNI versus 91.8% with IMNI (HR, 0.42; 95% CI, 0.22−0.82; P = .010) and the 7-year breast cancer mortality rates were 10.2% versus 4.9% (HR, 0.40; 95% CI, 0.17−0.99; P = .048). There were no differences in adverse effects including cardiac toxicity and radiation pneumonitis between treatment arms. Conclusion: Including IMNI in regional nodal irradiation did not significantly improve DFS for unselected women with node-positive breast cancer. Women with medially or centrally located tumors can be considered for applying IMNI when performing regional nodal irradiation.

Purpose The purpose of this work was to evaluate measures of increased departmental workload in relation to the occurrence of physician-related errors and incidents reaching the patient in radiation oncology. Materials and Methods All data were collected for the year 2013. Errors were defined as forms received by our departmental process improvement team; of these forms, only those relating to physicians were included in the study. Incidents were defined as serious errors reaching the patient requiring appropriate action; these were reported through a separate system. Workload measures included patient volumes and physician schedules and were obtained through departmental records for daily and monthly data. Errors and incidents were analyzed for relation with measures of workload using logistic regression modeling. Results Ten incidents occurred in the year. The number of patients treated per day was a significant factor relating to incidents (P < 0.003). However, the fraction of department physicians off-duty and the ratio of patients to physicians were not found to be significant factors relating to incidents. Ninety-one physician-related errors were identified, and the ratio of patients to physicians (rolling average) was a significant factor relating to errors (P < 0.03). The number of patients and the fraction of physicians off-duty were not significant factors relating to errors. A rapid increase in patient treatment visits may be another factor leading to errors and incidents. All incidents and 58% of errors occurred in months where there was an increase in the average number of fields treated per day from the previous month; 6 of the 10 incidents occurred in August, which had the highest average increase at 26%. Conclusions Increases in departmental workload, especially rapid changes, may lead to higher occurrence of errors and incidents in radiation oncology. When the department is busy, physician errors may be perpetuated owing to an overwhelmed departmental checks system, leading to incidents reaching the patient. Insights into workload and workflow will allow for the development of targeted approaches to preventing errors and incidents.

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Batch and column sorption/desorption experiments were conducted to quantify the retardation of tritium and cesium in brine‐saturated mudstone, halite, and carbonate rocks from Palo Duro Basin, Texas, one of the three sites originally nominated by the U.S. Department of Energy for construction of a civilian nuclear waste repository. Retardation factors (R) were determined using six different methods, including batch sorption equilibrium, fitting of two transport models, breakthrough area integration, and pore volume displacement at C/C0= 0.5, for both the sorption and desorption parts of the breakthrough curves. The breakthrough area integration method resulted in R values consistently lower than the other methods, which were in reasonable agreement. The data indicated very small retardation for cesium in all the media, except mudstone, which exhibited moderate retardation (R < 3.5). It was shown that the small extent of cesium retardation was most possibly caused by the strong competition for sorption sites of the components of the saturated brine, which were several orders of magnitude higher in concentration than cesium. Tritium breakthrough curves for all media tested were accurately simulated by the local equilibrium advection‐dispersion model (model I). With the exception of mudstone, cesium breakthrough curves were also adequately simulated by model I. The cesium breakthrough curve for mudstone exhibited considerable tailing on the desorption side of the curve, which was best described by the two‐site kinetic sorption model II. This was attributed to chemical nonequilibrium (two types of sorption sites). Predicted breakthrough curves for cesium using model I were in good to reasonable agreement with measured breakthrough curves.

While stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer (NSCLC) results in excellent local control, distant metastases (DM) remain the most prevalent form of failure. In this analysis, we developed and internally validated a nomogram to predict DM following SBRT for NSCLC. Materials/Methods: We queried our institutional registry of patients treated with lung SBRT over the past decade (2003e2014) and identified 729 patients with early-stage NSCLC eligible for analysis. All patients were treated with definitive intent. Initial patient and tumor variables predicting the likelihood of developing distant metastases were identified from a multivariable Cox proportional hazard model. A nomogram was developed from the initial model using 16 candidate variables and was reduced to the find the best fitting parsimonious model. The nomogram was then internally validated using a 1 000 bootstrap resampling process. Accuracy of the nomogram was measured using c-statistics. Results: The median follow-up was 15.2 months. One hundred fifty-seven patients (22%) developed DM at a median time of 10.3 (range, 0.2e68.4) months. The median time to death after development of DM was 4.5 months. Sites of DM included lung (113/157 patients), bone (36/157 patients), liver (27/157 patients), brain (25/157 patients), adrenal (8/157 patients), and other (7/157 patients). Age at start of radiation therapy (P Z 0.051), tumor size (P Z .009), PET SUV (P Z .026), and the presence of synchronous primaries (P Z .048) were all predictive of DM on multivariable analysis. Using seven patient and tumor variables (Age, BMI, Charlson Comorbidity Index, tumor size, PET SUV, medical operability, and presence of a synchronous primary NSCLC), our nomogram successfully predicted distant metastasis and has an internally validated cstatistic of 0.606 (95% CI: 0.563, 0.648). Internal validation with bootstrapping demonstrated persistent validity of the nomogram in predicting distant metastases. Conclusion: This novel internally validated nomogram can predict the risk of distant metastases in early-stage NSCLC treated with SBRT. External validation of this nomogram is warranted. This nomogram may help define subgroups for stratification in future clinical trials and identify patients who may benefit from adjuvant systemic therapies following lung SBRT.