K. Kosaki

Clinical outcomes of stereotactic body radiotherapy for stage I non-small cell lung cancer using different doses depending on tumor size

BackgroundThe treatment schedules for stereotactic body radiotherapy (SBRT) for lung cancer vary from institution to institution. Several reports have indicated that stage IB patients had worse outcomes than stage IA patients when the same dose was used. We evaluated the clinical outcomes of SBRT for stage I non-small cell lung cancer (NSCLC) treated with different doses depending on tumor diameter.MethodsBetween February 2004 and November 2008, 124 patients with stage I NSCLC underwent SBRT. Total doses of 44, 48, and 52 Gy were administered for tumors with a longest diameter of less than 1.5 cm, 1.5-3 cm, and larger than 3 cm, respectively. All doses were given in 4 fractions.ResultsFor all 124 patients, overall survival was 71%, cause-specific survival was 87%, progression-free survival was 60%, and local control was 80%, at 3 years. The 3-year overall survival was 79% for 85 stage IA patients treated with 48 Gy and 56% for 37 stage IB patients treated with 52 Gy (p = 0.05). At 3 years, cause-specific survival was 91% for the former group and 79% for the latter (p = 0.18), and progression-free survival was 62% versus 54% (p = 0.30). The 3-year local control rate was 81% versus 74% (p = 0.35). The cumulative incidence of grade 2 or 3 radiation pneumonitis was 11% in stage IA patients and 30% in stage IB patients (p = 0.02).ConclusionsThere was no difference in local control between stage IA and IB tumors despite the difference in tumor size. The benefit of increasing the SBRT dose for larger tumors should be investigated further.

Hypofractionated Stereotactic Body Radiotherapy for Primary and Metastatic Liver Tumors Using the Novalis Image-Guided System: Preliminary Results regarding Efficacy and Toxicity

The purpose of this study was to evaluate the efficacy and toxicity of stereotactic body radiotherapy (SBRT) for primary and metastatic liver tumors using the Novalis image-guided radiotherapy system. After preliminarily treating liver tumors using the Novalis system from July 2006, we started a protocol-based study in February 2008. Eighteen patients (6 with primary hepatocellular carcinoma and 12 with metastatic liver tumor) were treated with 55 or 50 Gy, depending upon their planned dose distribution and liver function, delivered in 10 fractions over 2 weeks. Four non-coplanar and three coplanar static beams were used. Patient age ranged from 54 to 84 years (median: 72 years). The Child-Pugh classification was Grade A in 17 patients and Grade B in 1. Tumor diameter ranged from 12 to 35 mm (median: 23 mm). Toxicities were evaluated according to the Common Terminology Criteria of Adverse Events version 4.0, and radiation-induced liver disease (RILD) was defined by Lawrences criterion. The median follow-up period was 14.5 months. For all patients, the 1-year overall survival and local control rates were 94% and 86%, respectively. A Grade 1 liver enzyme change was observed in 5 patients, but no RILD or chronic liver dysfunction was observed. SBRT using the Novalis image-guided system is safe and effective for treating primary and metastatic liver tumors. Further investigation of SBRT for liver tumors is warranted. In view of the acceptable toxicity observed with this protocol, we have moved to a new protocol to shorten the overall treatment time and escalate the dose.

Correlation between the serum KL-6 level and the grade of radiation pneumonitis after stereotactic body radiotherapy for stage I lung cancer or small lung metastasis.

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Comparison of intensity modulated radiotherapy (IMRT) with intensity modulated particle therapy (IMPT) using fixed beams or an ion gantry for the treatment of patients with skull base meningiomas.

see front matter 2011 Elsevier Irelan doi:10.1016/j.radonc.2011.05.031 ⇑ Corresponding author. Address: Department of Ra sity Graduate School of Medical Sciences, 1 Kawasu Nagoya 467-8601, Japan. E-mail address: h-iwa-ncu@nifty.com (H. Iwata). Serum levels of a sialylated carbohydrate antigen KL-6, a marker for interstitial pneumonitis, were serially measured before and after stereotactic body radiotherapy (SBRT) for lung tumors. It was suggested that KL-6 levels before and after SBRT would help to predict the occurrence of P Grade 2 radiation pneumonitis. 2011 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 101 (2011) 267–270

Early response and local control of stage I non-small-cell lung cancer after stereotactic radiotherapy: difference by histology

BackgroundTo examine the potential improvement in treatment planning for patients with skull base meningioma using IMRT compared to carbon ion or proton beams with and without a gantry.MethodsFive patients originally treated with photon IMRT were selected for the study. Ion beams were chosen using a horizontal beam or an ion gantry. Intensity controlled raster scanning and the intensity modulated particle therapy mode were used for plan optimization. The evaluation included analysis of dose-volume histograms of the target volumes and organs at risk.ResultsIn comparison with carbon and proton beams only with horizontal beams, carbon ion treatment plans could spare the OARs more and concentrated on the target volumes more than proton and photon IMRT treatment plans. Using only a horizontal fixed beam, satisfactory plans could be achieved for skull base tumors.ConclusionThe results of the case studies showed that using IMPT has the potential to overcome the lack of a gantry for skull base tumors. Carbon ion plans offered slightly better dose distributions than proton plans, but the differences were not clinically significant with established dose prescription concepts.

Radiotherapy for hilar or mediastinal lymph node metastases after definitive treatment with stereotactic body radiotherapy or surgery for stage I non-small cell lung cancer

To investigate the possible influences of various factors on tumor response to radiation, regression speeds and long‐term local control rates of primary adenocarcinoma and squamous cell carcinoma of the lung after stereotactic body radiotherapy were evaluated. Ninety‐one patients (65 men and 26 women) with a median age of 76 years were serially examined using computed tomography at 2, 4 and 6 months after treatment. Tumor histology was adenocarcinoma in 62 patients and squamous cell carcinoma in 29 patients. The prescribed dose was 48 Gy in four fractions given twice a week for T1 tumors (≤3 cm) and 52 Gy in four fractions given twice a week for T2 tumors (3–5 cm). Tumor shrinkage speed and 3‐year local control rates were similar between T1 and T2 tumors and between patients with normal pulmonary function and those with impaired function. Squamous cell carcinomas shrank faster than adenocarcinomas at 2 and 4 months after radiation, but mean relative tumor size at 6 months and local control rates at 3 years did not differ significantly between the two histologies. Tumors in patients with a higher hemoglobin level tended to shrink faster but the control rates were not different. It is concluded that, although squamous cell carcinoma shrinks faster than adenocarcinoma, the two types of lung cancer are of similar radiosensitivity in terms of long‐term control rates. Radiosensitivity should not be evaluated by early tumor response. (Cancer Sci 2013; 104: 130–134)

Regression curves of brain metastases after gamma knife irradiation: Difference by tumor and patient characteristics

PURPOSE Management of regional lymph node (LN) recurrence is an important issue in definitive treatment of non-small cell lung cancer (NSCLC). We evaluated clinical outcomes of conventional radiotherapy for hilar or mediastinal LN metastases developing after stereotactic body radiotherapy (SBRT) or surgery for stage I NSCLC. METHODS AND MATERIALS Between 2004 and 2008, 26 patients with hilar or mediastinal LN metastases without local recurrence and distant metastasis after SBRT (n = 14) or surgery (n = 12) were treated with conventional radiotherapy. Twelve of the 14 post-SBRT patients (86%) were judged medically inoperable at the time of SBRT. All patients were treated to the hilum and mediastinum with conventional daily fractions of 2.0 Gy (n = 25) or 2.4 Gy (n = 1). The median total dose for treating metastatic LN was 60 Gy (range, 54-66 Gy) for the post-SBRT patients and 65 Gy (range, 60-66 Gy) for the post-surgery patients. Only 1 of the 14 post-SBRT patients and 8 of the 12 post-surgery patients received chemotherapy. RESULTS For all 26 patients, the overall and cause-specific survival rates at 3 years from radiation for LN metastases were 36% and 51%, respectively (14% and 39%, respectively, for the 14 post-SBRT patients and both 64% for the 12 post-surgery patients). Three of the SBRT patients were alive at 35 to 43 months with (n = 2) or without (n = 1) further recurrence, and 4 of the post-surgery patients were alive at 36 to 62 months with (n = 2) or without (n = 2) further recurrence. The incidence of ≥grade 2 pulmonary toxicity was 49% at 1 year (53% for post-SBRT patients and 44% for post-surgery patients). A grade 5 pulmonary toxicity was observed in 1 of the post-SBRT patients. CONCLUSIONS Conventional radiotherapy could successfully salvage LN relapses after SBRT as well as after surgery in 7 of 26 patients. Radiotherapy in this setting appears reasonably well tolerated.

Stereotactic radiotherapy using Novalis for skull base metastases developing with cranial nerve symptoms

Regression curves and local control rates of brain metastases after gamma knife treatment were evaluated to investigate differences in tumor response to radiation. A total of 203 metastases were serially evaluated using contrast‐enhanced MRI (or computed tomography) at 1, 2, 3, 4.5 and 6 months after a 20‐Gy dose. Differences were evaluated in regression curves and control rates between tumors ≥10 mm and tumors <10 mm in mean diameter, among three major histological subtypes of lung cancer, among adenocarcinomas of the lung, breast and colorectum, and between tumors in patients with above and below median hemoglobin levels. Smaller tumors shrank faster and yielded better control rates than larger tumors. Metastases from small cell and squamous cell carcinomas of the lung shrank faster than those from lung adenocarcinoma, but 6‐month control rates were not different. Breast adenocarcinomas tended to shrink faster than lung adenocarcinomas, but the control rates were not different among adenocarcinomas of the lung, breast and colorectum. Tumors in patients with higher hemoglobin levels tended to shrink faster but the control rates were not different. Small cell and squamous cell carcinomas of the lung regress more rapidly than adenocarcinomas, although local control rates might not differ significantly.