Second re-irradiation: efficacy, dose and toxicity in patients who received three courses of radiotherapy with overlapping fields.

PURPOSE: To explore the outcome, cumulative dose and toxicity in 23 patients after a third radiation treatment, with a partial or complete overlap of the previous two irradiated regions. METHODS AND MATERIAL: The dose summation of the three radiation plans was made by the planning system. For patients treated with cyberknife or brachytherapy dose summation was done by dose point calculations. Efficacy and toxicity was scored by looking at the reduction of tumor, pain and bleeding. RESULTS: Symptomatic response was observed in 81% and 73% of the patients after, respectively, the third and second radiation. The median cumulative maximum dose to the tumor and its regions was 133Gy(3) (range: 82-496Gy(3)). The median corrected cumulative dose for the rectum, bowel and bladder resulted in 91Gy(3), 73Gy(3) and 79Gy(3), respectively. Grade 3 acute skin toxicity was only seen in the third radiation course. CONCLUSION: The constraints of 100Gy(3) for rectum, 90Gy(3) for bowel and 110Gy(3) for bladder are safe and can be used as guidelines in the decision for re-irradiation. Symptomatic relieve was seen in 81% of the patients with low grade 3 and no grade 4 acute and late toxicity.

Stereotactic body radiation therapy for liver tumors: impact of daily setup corrections and day-to-day anatomic variations on dose in target and organs at risk.

PURPOSE: To assess day-to-day differences between planned and delivered target volume (TV) and organ-at-risk (OAR) dose distributions in liver stereotactic body radiation therapy (SBRT), and to investigate the dosimetric impact of setup corrections. METHODS AND MATERIALS: For 14 patients previously treated with SBRT, the planning CT scan and three treatment scans (one for each fraction) were included in this study. For each treatment scan, two dose distributions were calculated: one using the planned setup for the body frame (no correction), and one using the clinically applied (corrected) setup derived from measured tumor displacements. Per scan, the two dose distributions were mutually compared, and the clinically delivered distribution was compared with planning. Doses were recalculated in equivalent 2-Gy fraction doses. Statistical analysis was performed with the linear mixed model. RESULTS: With setup corrections, the mean loss in TV coverage relative to planning was 1.7%, compared with 6.8% without corrections. For calculated equivalent uniform doses, these figures were 2.3% and 15.5%, respectively. As for the TV, mean deviations of delivered OAR doses from planning were small (between -0.4 and +0.3 Gy), but the spread was much larger for the OARs. In contrast to the TV, the mean impact of setup corrections on realized OAR doses was close to zero, with large positive and negative exceptions. CONCLUSIONS: Daily correction of the treatment setup is required to obtain adequate TV coverage. Because of day-to-day patient anatomy changes, large deviations in OAR doses from planning did occur. On average, setup corrections had no impact on these doses. Development of new procedures for image guidance and adaptive protocols is warranted.

Quality of life after stereotactic body radiation therapy for primary and metastatic liver tumors.

PURPOSE: Stereotactic body radiation therapy (SBRT) provides a high local control rate for primary and metastatic liver tumors. The aim of this study is to assess the impact of this treatment on the patient's quality of life. This is the first report of quality of life associated with liver SBRT. METHODS AND MATERIALS: From October 2002 to March 2007, a total of 28 patients not suitable for other local treatments and with Karnofsky performance status of at least 80% were entered in a Phase I-II study of SBRT for liver tumors. Quality of life was a secondary end point. Two generic quality of life instruments were investigated, EuroQol-5D (EQ-5D) and EuroQoL-Visual Analogue Scale (EQ-5D VAS), in addition to a disease-specific questionnaire, the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ C-30). Points of measurement were directly before and 1, 3, and 6 months after treatment. Mean scores and SDs were calculated. Statistical analysis was performed using paired-samples t-test and Student t-test. RESULTS: The calculated EQ-5D index, EQ-5D VAS and QLQ C-30 global health status showed that mean quality of life of the patient group was not significantly influenced by treatment with SBRT; if anything, a tendency toward improvement was found. CONCLUSIONS: Stereotactic body radiation therapy combines a high local control rate, by delivering a high dose per fraction, with no significant change in quality of life. Multicenter studies including larger numbers of patients are recommended and under development.

Target coverage in image-guided stereotactic body radiotherapy of liver tumors.

PURPOSE: To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. METHODS AND MATERIALS: By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV(+)) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV(+), derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. RESULTS: Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full (> or = 99%) ITV(+) coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small (< or = 2 mm, 1 standard deviation), but large craniocaudal displacements (maximal 7.2 mm) were occasionally observed. CONCLUSION: Daily, CT-assisted patient setup may substantially improve tumor coverage, especially with the automated three-dimensional procedure. In the present treatment design, patient stability in the SBF should be verified with portal imaging.

Stereotactic body radiation therapy for primary and metastatic liver tumors: A single institution phase i-ii study.

The feasibility, toxicity and tumor response of stereotactic body radiation therapy (SBRT) for treatment of primary and metastastic liver tumors was investigated. From October 2002 until June 2006, 25 patients not suitable for other local treatments were entered in the study. In total 45 lesions were treated, 34 metastases and 11 hepatocellular carcinoma (HCC). Median follow-up was 12.9 months (range 0.5-31). Median lesion size was 3.2 cm (range 0.5-7.2) and median volume 22.2 cm3 (range 1.1-322). Patients with metastases, HCC without cirrhosis, and HCC < 4 cm with cirrhosis were mostly treated with 3 x 12.5 Gy. Patients with HCC > or =4 cm and cirrhosis received 5 x 5 Gy or 3 x 10 Gy. The prescription isodose was 65%. Acute toxicity was scored following the Common Toxicity Criteria and late toxicity with the SOMA/LENT classification. Local failures were observed in two HCC and two metastases. Local control rates at 1 and 2 years for the whole group were 94% and 82%. Acute toxicity grade > or =3 was seen in four patients; one HCC patient with Child B developed a liver failure together with an infection and died (grade 5), two metastases patients presented elevation of gamma glutamyl transferase (grade 3) and another asthenia (grade 3). Late toxicity was observed in one metastases patient who developed a portal hypertension syndrome with melena (grade 3). SBRT was feasible, with acceptable toxicity and encouraging local control. Optimal dose-fractionation schemes for HCC with cirrhosis have to be found. Extreme caution should be used for patients with Child B because of a high toxicity risk.