Palliative radiation for bone metastases from hepatocellular carcinoma: practice patterns and the amount of remaining life spent receiving treatment.

BACKGROUND: Palliative radiation therapy (RT) for bone metastases (BMs) is a common practice. Wide variation exists in clinically used dose schema despite numerous studies demonstrating palliative equipoise between single and multifraction courses. We hypothesize that fraction scheme for palliating BMs for hepatocellular carcinoma (HCC) significantly affects how patients spend their remaining time. METHODS: Patients with osseous HCC metastases who received RT were identified from the National Cancer Database [2004-2013]. The percentage of remaining life spent receiving radiation therapy (PRLSRT) and the number of incomplete RT courses were calculated. Kaplan-Meier analysis and Cox proportional hazards models were used to evaluate trends and predictors. RESULTS: A total of 1,331 patients met the inclusion criteria. Median overall survival (OS) was 3.3 months. Just 49 (3.7%) of patients received single fraction RT and 34% received >10 fractions. The mean and median PRLSRT were as follows: 1 fraction (8.9% and 3.0%), 2-5 fractions (32.9% and 24.3%), 6-10 fractions (27.2% and 15.9%), and >10 fractions (24.1% and 14.4%). Of the patients with PRLSRT >50%, 99.6% received multifraction RT. The proportion of incomplete RT courses increased as fraction size decreased from 17.6% with 4 Gy to 34% with 2 Gy. CONCLUSIONS: Single fraction palliative RT is vastly underutilized despite no additional palliative benefit with multifraction RT. PRLSRT significantly increased with multifraction RT. In the palliative treatment of painful BMs from HCC, single fraction treatment reduces time spent receiving radiation treatments and maximizes the number of patients who complete the prescribed treatment.

VenaTech Convertible Vena Cava Filter 6 Months after Conversion Follow-up.

PURPOSE: To report device-related adverse events 6 months after placement or conversion of the VenaTech convertible vena cava filter (VTCF). MATERIALS AND METHODS: A review of 6-month follow-up data of an investigational device exemption multicenter, prospective, single-arm study was performed. The VTCF was implanted in 149 patients. Conversion was attempted in 64.4% of those patients (n = 96) and successfully in 96.9% of the patients (n = 93). A total of 76 patients completed imaging evaluation at 6 months after filter conversion. Patients who required continued venous thromboembolism prophylaxis at 6 months did not undergo a conversion attempt and were designated as nonconverted filter subjects. A total of 28 nonconverted filter subjects completed imaging evaluation at 6 months after implantation. RESULTS: Evaluation of patients at 6 months after conversion demonstrated 1 of 76 (1.3%) inferior vena cava (IVC) perforations with a filter strut greater than 3 mm outside of the caval lumen. No cases of recurrent PE, clinically significant filter migration, filter fracture, or IVC thrombosis were reported in the converted subjects. In the nonconverted filter subjects, there was a 14.3% (4 of 28) complete or nearly complete rate of IVC thromboses. There were no cases of recurrent pulmonary embolism, penetration, fracture, or spontaneous conversion in the nonconverted filter subjects. There was a significant reduction in the rate of IVC thrombosis and migration in the converted cohort compared to that in the nonconverted cohort. CONCLUSIONS: At 6 months, the VTCF demonstrated low adverse event rates in the converted configuration, whereas a minority of patients with the nonconverted configuration demonstrated a high risk of IVC thrombosis.

The Dosimetric Impact of Interfractional Organ-at-Risk Movement During Liver Stereotactic Body Radiation Therapy.

PURPOSE: Stereotactic body radiation therapy (SBRT) is an effective therapy for treating liver malignancies. However, little is known about interfractional dose variations to adjacent organs at risk (OARs). We examine the effects of interfractional organ movement and setup variation on dose delivered to OARs in patients receiving liver SBRT. METHODS AND MATERIALS: Thirty patients treated with liver SBRT were analyzed. Daily image guidance with diagnostic quality computed tomography-on-rails imaging was performed before each fraction. In phase 1, these daily images were used to delineate all OARs including the liver, heart, right kidney, esophagus, stomach, duodenum, and large bowel in 10 patients. In phase 2, only OARS in close proximity to the target were contoured in 20 additional patients. Dose distribution on each daily computed tomography was generated, and daily doses to each OAR were recorded and compared with clinical thresholds to determine whether a daily dose excess (DDE) occurred. RESULTS: In phase 1, significant interfractional dose differences between planned and delivered dose to OARs were observed, but differences were rarely clinically significant, with just 1 DDE. In phase 2, multiple DDEs were recorded for OARs close to the target, mainly involving the stomach, heart, and esophagus. Tumors in the hilum and liver segments I, IV, and VIII were the most common locations for DDEs. On root cause analysis, 3 etiologies of DDE emerged: craniocaudal shift (69.2%), anatomic changes (28.2%), and anteroposterior shifts (2.6%). CONCLUSIONS: OARs close to liver lesions may receive higher doses than expected during SBRT owing to interfractional variations in OARs relative to the target. These differences in planned versus expected dose can lead to toxicity. Efforts to better evaluate OARs with daily image guidance may help reduce risks. Application of adaptive replanning and improved and real-time image guidance could mitigate risks of toxicity, and further study into their applications is warranted.

Stereotactic body radiation therapy for hepatocellular carcinoma: Practice patterns, dose selection and factors impacting survival.

BACKGROUND: Stereotactic body radiation therapy (SBRT) is an emerging option for unresectable hepatocellular carcinoma (HCC) without consensus regarding optimal dose schemas. This analysis identifies practice patterns and factors that influence dose selection and overall survival, with particular emphasis on dose and tumor size. MATERIALS/METHODS: Query of the National Cancer Database (NCDB) identified patients with unresectable, nonmetastatic HCC who received SBRT from 2004 to 2013. Biological Effective Dose (BED) was calculated for each patient in order to uniformly analyze different fractionation regimens. RESULTS: A total of 456 patients met the inclusion criteria. The median BED was 100 Gy (22.5-208.0), which corresponded to the most common dose fractionation (50 Gy in five fractions). Various factors influenced dose selection including tumor size (P < 0.001), tumor stage (P = 0.002), and facility case volume (<0.001). On multivariate analysis, low BED (<75 Gy, HR 2.537, P < 0.001; 75-100 Gy, HR 1.986, P = 0.007), increasing tumor size (HR 1.067, P = 0.032), elevated AFP (HR 1.585, P = 0.019), stage 3 (HR 1.962, P < 0.001), low-volume facilities (1-5 cases HR 1.687, P = 0.006), and a longer time interval from diagnosis to SBRT (>2 to ≤4 months, HR 1.456, P = 0.048; >4 months, HR 2.192, P < 0.001) were associated with worse survival. CONCLUSION: SBRT use is increasing for HCC, and multiple regimens are clinically employed. Although high BED was associated with improved outcomes, multiple factors contributed to the dose selection with favorable patients receiving higher doses. Continued efforts to enhance radiation planning and delivery may help improve utilization, safety, and efficacy.