Joost J. Nuyttens

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 3×12.5 Gy. Patients with HCC ≥4cm and cirrhosis received 5×5 Gy or 3×10 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 ≥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.

Clinical accuracy of the respiratory tumor tracking system of the cyberknife: assessment by analysis of log files.

PURPOSE To quantify the clinical accuracy of the respiratory motion tracking system of the CyberKnife treatment device. METHODS AND MATERIALS Data in log files of 44 lung cancer patients treated with tumor tracking were analyzed. Errors in the correlation model, which relates the internal target motion with the external breathing motion, were quantified. The correlation model error was compared with the geometric error obtained when no respiratory tracking was used. Errors in the prediction method were calculated by subtracting the predicted position from the actual measured position after 192.5 ms (the time lag to prediction in our current system). The prediction error was also measured for a time lag of 115 ms and a new prediction method. RESULTS The mean correlation model errors were less than 0.3 mm. Standard deviations describing intrafraction variations around the whole-fraction mean error were 0.2 to 1.9 mm for cranio-caudal, 0.1 to 1.9 mm for left-right, and 0.2 to 2.5 mm for anterior-posterior directions. Without the use of respiratory tracking, these variations would have been 0.2 to 8.1 mm, 0.2 to 5.5 mm, and 0.2 to 4.4 mm. The overall mean prediction error was small (0.0 +/- 0.0 mm) for all directions. The intrafraction standard deviation ranged from 0.0 to 2.9 mm for a time delay of 192.5 ms but was halved by using the new prediction method. CONCLUSIONS Analyses of the log files of real clinical cases have shown that the geometric error caused by respiratory motion is substantially reduced by the application of respiratory motion tracking.

Stereotactic radiotherapy with real-time tumor tracking for non-small cell lung cancer: Clinical outcome

PURPOSE To report the clinical outcome of treatment using real-time tumor tracking for 70 patients with inoperable stage I non-small cell lung cancer (NSCLC). MATERIALS AND METHODS Seventy inoperable patients with peripherally located early-stage NSCLC were treated with 45 or 60 Gy in three fractions using CyberKnife. Pathology was available in 51% of patients. Thirty-nine patients had a T1-tumor and 31 had a T2-tumor. Markers were placed using the vascular, percutaneous intra-, or extra-pulmonary approach, depending on the risk of pneumothorax. RESULTS The actuarial 2-year local control rate for patients treated with 60 Gy was 96%, compared to 78% for patients treated with a total dose of 45 Gy (p=0.197). All local recurrences (n=4) occurred in patients with T2-tumors. Overall survival for the whole group at two years was 62% and the cause specific survival was 85%. The median follow-up was 15 months. Grade 3 toxicity occurred in two patients (3%) after marker placement. Treatment-related late grade 3 toxicity occurred in 7 patients (10%). No grade > or = 4 toxicity occurred. CONCLUSION Excellent local control of 96% at 1- and 2-years was achieved using 60 Gy in three fractions for NSCLC patients treated with the real-time tumor tracking. Toxicity was low.

Lung tumor tracking during stereotactic radiotherapy treatment with the CyberKnife: Marker placement and early results

Lung tumor tracking during stereotactic radiotherapy with the CyberKnife requires the insertion of markers in or close to the tumor. To reduce the risk of pneumothorax, three methods of marker placement were used: 1) intravascular coil placement, 2) percutaneous intrathoracal, and 3) percutaneous extrathoracal placement. We investigated the toxicity of marker placement and the tumor response of the lung tumor tracking treatment. Markers were placed in 20 patients with 22 tumors: 13 patients received a curative treatment, seven a palliative. The median Charlson Comorbidity Score was 4 (range: 1–8). Platinum fiducials and intravascular embolisation coils were used as markers. In total, 78 markers were placed: 34 intrathoracal, 23 intravascular and 21 extrathoracal. The PTV equaled the GTV + 5 mm. A median dose of 45 Gy (range: 30–60 Gy, in 3 fractions) was prescribed to the 70–85% isodose. The response was evaluated with a CTscan performed 6–8 weeks after the last treatment and routinely thereafter. The median follow-up was 4 months (range: 2–11). No severe toxicity due to the marker placement was seen. Pneumothorax was not seen. The local control was 100%. Four tumors in four patients showed a complete response, 15 tumors in 14 patients a partial response, and three tumors in two patients with metastatic disease had stable disease. No severe toxicity of marker placement was seen due to the appropriate choice of one of the three methods. CyberKnife tumor tracking with markers is feasible and resulted in excellent tumor response. Longer follow-up is needed to validate the local control.

Chemoradiation therapy for rectal cancer in the distal rectum followed by organ-sparing transanal endoscopic microsurgery (CARTS study)

This prospective multicentre study was performed to quantify the number of patients with minimal residual disease (ypT0–1) after neoadjuvant chemoradiotherapy and transanal endoscopic microsurgery (TEM) for rectal cancer.

High-dose-rate intraoperative radiotherapy for close or positive margins in patients with locally advanced or recurrent rectal cancer.

PURPOSE A high-dose-rate intraoperative radiotherapy (HDR-IORT) technique for rectum cancer was developed and the technique, local failure, and survival were analyzed. METHODS AND MATERIALS After the exclusion of metastatic patients, 37 patients were treated with external beam RT, surgery, and HDR-IORT between 1997 and 2000. Primary locally advanced rectum cancer was found in 18 patients and recurrent disease in 19. HDR-IORT was only administered if the resection margins were < or =2 mm. The flexible intraoperative template is a 5-mm-thick pad with 1-cm-spaced parallel catheters. Clips were placed during surgery to define the target area. A dose of 10 Gy was prescribed at a 1 cm depth from the template surface and calculated using standard plans. After treatment, the dose at the clips was calculated using the reconstructed template geometry and the actual treatment dwell times. The median follow-up of surviving patients was 3 years. No patients were lost to follow-up. RESULTS Overall, 12 patients (32%) had local recurrence, 5 (14%) of which were in the HDR-IORT field. The 3-year local failure rate for primary tumors and recurrent tumors was 19% and 52%, respectively (p = 0.0042). The 3-year local failure rate was 37% for negative margins and 26% for positive margins (p = 0.51). A high mean dose at the clip (17.3 Gy) was found. The overall survival was significantly different for primary vs. recurrent tumors, stage, and grade. CONCLUSION Because of the HDR technique, a high dose at the clips was found, with good local control. More out-of-field than in-field failures were seen. The local failure rate was significantly different for primary vs. recurrent disease.

Outcome of four-dimensional stereotactic radiotherapy for centrally located lung tumors.

PURPOSE To assess local control, overall survival, and toxicity of four-dimensional, risk-adapted stereotactic body radiotherapy (SBRT) delivered while tracking respiratory motion in patients with primary and metastatic lung cancer located in the central chest. METHODS Fifty-eight central lesions of 56 patients (39 with primary, 17 with metastatic tumors) were treated. Fifteen tumors located near the esophagus were treated with 6 fractions of 8 Gy. Other tumors were treated according to the following dose escalation scheme: 5 fractions of 9 Gy (n = 6), then 5 fractions of 10 Gy (n = 15), and finally 5 fractions of 12 Gy (n = 22). RESULTS Dose constraints for critical structures were generally achieved; in 21 patients the coverage of the PTV was reduced below 95% to protect adjacent organs at risk. At a median follow-up of 23 months, the actuarial 2-years local tumor control was 85% for tumors treated with a BED >100 Gy compared to 60% for tumors treated with a BED ≤ 100 Gy. No grade 4 or 5 toxicity was observed. Acute grade 1-2 esophagitis was observed in 11% of patients. CONCLUSION SBRT of central lung lesions can be safely delivered, with promising early tumor control in patients many of whom have severe comorbid conditions.

The CARTS study: Chemoradiation therapy for rectal cancer in the distal rectum followed by organ-sparing transanal endoscopic microsurgery

BackgroundThe CARTS study is a multicenter feasibility study, investigating the role of rectum saving surgery for distal rectal cancer.Methods/DesignPatients with a clinical T1-3 N0 M0 rectal adenocarcinoma below 10 cm from the anal verge will receive neoadjuvant chemoradiation therapy (25 fractions of 2 Gy with concurrent capecitabine). Transanal Endoscopic Microsurgery (TEM) will be performed 8 - 10 weeks after the end of the preoperative treatment depending on the clinical response.Primary objective is to determine the number of patients with a (near) complete pathological response after chemoradiation therapy and TEM. Secondary objectives are the local recurrence rate and quality of life after this combined therapeutic modality. A three-step analysis will be performed after 20, 33 and 55 patients to ensure the feasibility of this treatment protocol.DiscussionThe CARTS-study is one of the first prospective multicentre trials to investigate the role of a rectum saving treatment modality using chemoradiation therapy and local excision. The CARTS study is registered at clinicaltrials.gov (NCT01273051)

Quality of life after stereotactic radiotherapy for stage I non-small-cell lung cancer.

PURPOSE To determine the impact of stereotactic radiotherapy on the quality of life of patients with inoperable early-stage non-small-cell lung cancer (NSCLC). Overall survival, local tumor control, and toxicity were also evaluated in this prospective study. METHODS AND MATERIALS From January 2006 to February 2008, quality of life, overall survival, and local tumor control were assessed in 39 patients with pathologically confirmed T1 to 2N0M0 NSCLC. These patients were treated with stereotactic radiotherapy. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ) C30 and the QLQ LC13 lung cancer-specific questionnaire were used to investigate changes in quality of life. Assessments were done before treatment, at 3 weeks, and at 2, 4, 6, 9, and 12 months after treatment, until death or progressive disease. Toxicity was evaluated using common terminology criteria for adverse events version 3.0. RESULTS Emotional functioning improved significantly after treatment. Other function scores and QLQ C30 and QLQ LC13 lung symptoms (such as dyspnea and coughing) showed no significant changes. The overall 2-year survival rate was 62%. After a median follow-up of 17 months, 1 patient had a local recurrence (3%). No grade 4 or 5 treatment-related toxicity occurred. Grade 3 toxicity consisted of thoracic pain, which occurred in 1 patient within 4 months of treatment, while it occurred thereafter in 2 patients. CONCLUSIONS Quality of life was maintained, and emotional functioning improved significantly after stereotactic radiotherapy for stage I NSCLC, while survival was acceptable, local tumor control was high, and toxicity was low.

Preoperative Radiotherapy Improves Outcome in Recurrent Rectal Cancer

PURPOSEWhen local recurrent rectal cancer is diagnosed without signs of metastases, a potentially curative resection can be performed. This study was designed to compare the results of preoperative radiotherapy followed by surgery with surgery only.METHODSBetween 1985 and 2003, 117 patients with recurrent rectal cancer were prospectively entered in our database. Ninety-two patients were suitable for resection with curative intent. Preoperative radiation with a median dosage of 50 Gy was performed in 59 patients; 33 patients did not receive preoperative radiotherapy. The median age of the patients was respectively 66 and 62 years.RESULTSThe median follow-up of patients alive for the total group was 16 (range, 4–156) months. Tumor characteristics were comparable between the two groups. Complete resections were performed in 64 percent of the patients who received preoperative radiation and 45 percent of the nonirradiated patients. A complete response after radiotherapy was found in 10 percent of the preoperative irradiated patients (n = 6). There were no differences in morbidity and reintervention rate between the two groups. Local control after preoperative radiotherapy was statistically significantly higher after three and five years (P = 0.036). Overall survival and metastases-free survival were not different in both groups. Complete response to preoperative radiotherapy was predictive for an improved survival.CONCLUSIONSPreoperative radiotherapy for recurrent rectal cancer results in a higher number of complete resections and an improved local control compared with patients treated without radiotherapy. Preoperative radiotherapy should be standard treatment for patients with recurrent rectal cancer.