Use of a Radiation Tumor Bed Boost After Breast-Conserving Surgery and Whole-Breast Irradiation: Time Trends and Correlates

PURPOSE

We sought to evaluate time trends and correlates of the use of a radiation tumor bed boost (TBB) after breast-conserving surgery and either conventional or hypofractionated whole-breast irradiation (CWBI or HWBI) for patients with early stage breast cancer.

METHODS AND MATERIALS

The National Cancer Database was queried for patients diagnosed between 2012 and 2016. We evaluated the utilization of TBB before and after publication of the Society of Surgical Oncology-American Society for Radiation Oncology margin guidelines in relation to sociodemographic variables, treatment facility, tumor characteristics, and whole-breast fractionation.

RESULTS

The population included 380,387 patients, of whom 76.7% received a TBB. Utilization of TBB decreased over time (2012-2013: 79.2%; 2014: 76.6%; 2015-2016: 74.7%; P < .001); this was seen for most subgroups evaluated. Rates of TBB differed by facility type and region. There was a decrease in TBB use in patients treated with CWBI over time (2012-2013: 84.9%; 2014: 83.5%; 2015-2016: 82.3%; P < .001) but an increase among patients treated with HWBI (2012-2013: 55.5%; 2014: 60.7%; 2015-2016: 65.1%; P < .001); this was also seen for low-risk patients (age >70 years, negative margins). Among patients undergoing HWBI, TBB was more frequently used when 15 fractions were used compared with 16 fractions (76.8% vs 59.1%; P < .001).

CONCLUSIONS

The use of TBB decreased over time, coinciding with the publication of new margin guidelines, for patients receiving CWBI and those with negative margins, but TBB use increased for patients treated with HWBI. Hence, fractionation regimen is a critical variable in analyzing changes over time in the practice patterns of TBB.

Stereotactic radiosurgery for brain metastases from malignant melanoma and the impact of hemorrhagic metastases

INTRODUCTION

Stereotactic radiosurgery (SRS) is a common treatment modality among patients with brain metastases, particularly from malignant melanoma. Our objective was to investigate the difference in local control, toxicity, and survival among patients with hemorrhagic and solid melanoma brain metastases.

METHODS

We collected demographic, treatment, local control, toxicity, and survival for 134 patients with a total of 936 intracranial melanoma metastases who underwent SRS between 1998 and 2015. Pre-radiosurgical diagnostic imaging was reviewed for evidence of hemorrhage (melanin-containing or clearly hemorrhagic).

RESULTS

The cohort consisted of 92 men and 42 women with a mea age of 61.7 years (range 21.2-84.9) at the time of radiosurgery. Overall survival of patients with brain metastases from malignant melanoma was 42, 31, 12% at 12, 24, and 72 months from date of first SRS. At 6 months, 43% of the patients with hemorrhagic metastases had local tumor control compared to 83% of solid melanoma metastases (p < 0.001). No significant difference in toxicity was noted between the two groups. Factors that were significantly associated with time to local tumor progression on multivariate analysis include prior WBRT (HR 1.62, p = 0.003), prior chemotherapy (HR 0.69, p = 0.011), margin dose (HR 0.88, p < 0.001) and radiographic features of melanin deposition (HR 3.73, p < 0.001), or clear hemorrhage (HR 2.20, p < 0.001).

CONCLUSIONS

Our findings demonstrate that hemorrhagic intracranial melanoma metastases are associated with inferior local tumor control when treated with SRS, as compared to solid tumors. These results highlight the importance of early radiosurgery among patients with melanoma brain metastases before hemorrhage occurs.

Evaluation of Delivery Costs for External Beam Radiation Therapy and Brachytherapy for Locally Advanced Cervical Cancer Using Time-Driven Activity-Based Costing

PURPOSE

To evaluate the delivery costs, using time-driven activity-based costing, and reimbursement for definitive radiation therapy for locally advanced cervical cancer.

METHODS AND MATERIALS

Process maps were created to represent each step of the radiation treatment process and included personnel, equipment, and consumable supplies used to deliver care. Personnel were interviewed to estimate time involved to deliver care. Salary data, equipment purchasing information, and facilities costs were also obtained. We defined the capacity cost rate (CCR) for each resource and then calculated the total cost of patient care according to CCR and time for each resource. Costs were compared with 2016 Medicare reimbursement and relative value units (RVUs).

RESULTS

The total cost of radiation therapy for cervical cancer was $12,861.68, with personnel costs constituting 49.8%. Brachytherapy cost $8610.68 (66.9% of total) and consumed 423 minutes of attending radiation oncologist time (80.0% of total). External beam radiation therapy cost $4055.01 (31.5% of total). Personnel costs were higher for brachytherapy than for the sum of simulation and external beam radiation therapy delivery ($4798.73 vs $1404.72). A full radiation therapy course provides radiation oncologists 149.77 RVUs with intensity modulated radiation therapy or 135.90 RVUs with 3-dimensional conformal radiation therapy, with total reimbursement of $23,321.71 and $16,071.90, respectively. Attending time per RVU is approximately 4-fold higher for brachytherapy (5.68 minutes) than 3-dimensional conformal radiation therapy (1.63 minutes) or intensity modulated radiation therapy (1.32 minutes).

CONCLUSIONS

Time-driven activity-based costing was used to calculate the total cost of definitive radiation therapy for cervical cancer, revealing that brachytherapy delivery and personnel resources constituted the majority of costs. However, current reimbursement policy does not reflect the increased attending physician effort and delivery costs of brachytherapy. We hypothesize that the significant discrepancy between treatment costs and physician effort versus reimbursement may be a potential driver of reported national trends toward poor compliance with brachytherapy, and we suggest re-evaluation of payment policies to incentivize quality care.

Clinical outcomes of helical conformal versus nonconformal palliative radiation therapy for axial skeletal metastases

PURPOSE

Palliative radiation therapy (RT) for bone metastases has traditionally been delivered with conventional, nonconformal RT (NCRT). Conformal RT (CRT) is potentially more complex and expensive than NCRT, but may reduce normal tissue dose and subsequently toxicity. In this retrospective analysis, we compared CRT with NCRT to investigate the association between conformality and toxicity.

METHODS AND MATERIALS

A retrospective analysis of patients receiving palliative RT for axial skeletal bone metastases from 2012 to 2014 was conducted. Patient and treatment characteristics were obtained including dosimetric variables, acute toxicity, and subjective pain during treatment and in the acute posttreatment period (≤60 days after completion). Statistical analyses included t tests, χ² tests, and multivariate logistic regression.

RESULTS

A total of 179 patients and 254 bone metastases were identified (142 CRT, 112 NCRT). The CRT and NCRT groups were well matched for baseline characteristics (number of fractions, field size, treatment sites, and concurrent chemotherapy). In multivariate logistic regression models, technique (CRT vs NCRT) was not associated with development of acute toxicity. Regarding toxicity, Eastern Cooperative Oncology Group performance status and total dose were significantly associated with a higher rate of acute toxicity during RT (odds ratios, 0.649 and 1.129 and P = .027 and .044, respectively), and only a higher number of vertebral bodies in the treatment field was significantly associated with acute toxicity post-treatment (odds ratios, 1.219, P = .028). CRT was associated with improvement in bone pain during and posttreatment (P = .049 and .045, respectively).

CONCLUSIONS

Our results demonstrate no difference in acute toxicity following palliative RT with CRT compared with NCRT for painful bone metastases; however, treatment volume did predict for increased toxicity. Larger studies may further elucidate the value of CRT including the impact of dose escalation for bone metastases and differences in patient reported outcomes between RT techniques.