Toshiaki Takeda

STEREOTACTIC BODY RADIOTHERAPY FOR PRIMARY LUNG CANCER AT A DOSE OF 50 GY TOTAL IN FIVE FRACTIONS TO THE PERIPHERY OF THE PLANNING TARGET VOLUME CALCULATED USING A SUPERPOSITION ALGORITHM

PURPOSE To retrospectively analyze the clinical outcomes of stereotactic body radiotherapy (SBRT) for patients with Stages 1A and 1B non-small-cell lung cancer. METHODS AND MATERIALS We reviewed the records of patients with non-small-cell lung cancer treated with curative intent between Dec 2001 and May 2007. All patients had histopathologically or cytologically confirmed disease, increased levels of tumor markers, and/or positive findings on fluorodeoxyglucose positron emission tomography. Staging studies identified their disease as Stage 1A or 1B. Performance status was 2 or less according to World Health Organization guidelines in all cases. The prescribed dose of 50 Gy total in five fractions, calculated by using a superposition algorithm, was defined for the periphery of the planning target volume. RESULTS One hundred twenty-one patients underwent SBRT during the study period, and 63 were eligible for this analysis. Thirty-eight patients had Stage 1A (T1N0M0) and 25 had Stage 1B (T2N0M0). Forty-nine patients were not appropriate candidates for surgery because of chronic pulmonary disease. Median follow-up of these 49 patients was 31 months (range, 10-72 months). The 3-year local control, disease-free, and overall survival rates in patients with Stages 1A and 1B were 93% and 96% (p = 0.86), 76% and 77% (p = 0.83), and 90% and 63% (p = 0.09), respectively. No acute toxicity was observed. Grade 2 or higher radiation pneumonitis was experienced by 3 patients, and 1 of them had fatal bacterial pneumonia. CONCLUSIONS The SBRT at 50 Gy total in five fractions to the periphery of the planning target volume calculated by using a superposition algorithm is feasible. High local control rates were achieved for both T2 and T1 tumors.

Stereotactic body radiotherapy (SBRT) for oligometastatic lung tumors from colorectal cancer and other primary cancers in comparison with primary lung cancer

PURPOSE To analyze local control of oligometastatic lung tumors (OLTs) compared with that of primary lung cancer after stereotactic body radiotherapy (SBRT). MATERIALS AND METHODS Retrospective record review of patients with OLTs who received SBRT with 50Gy in 5 fractions. Local control rates (LCRs), toxicities, and factors of prognostic significance were assessed. RESULTS Twenty-one colorectal OLTs, 23 OLTs from other origins, and 188 primary lung cancers were included. Multivariate analysis revealed only tumor origin was prognostically significant (p<0.05). The 1-year/2-year LCRs in colorectal OLTs and OLTs from other origins were 80%/72% and 94%/94%, respectively. The LCR in colorectal OLTs was significantly worse than that in OLTs from the other origins and primary lung cancers with pathological and clinical diagnosis (p<0.05, p<0.0001 and p<0.005). Among 44 OLT patients, Grades 2 and 3 radiation pneumonitis were identified in 2 and 1 patients, respectively. No other toxicities of more than Grade 3 occurred. CONCLUSION SBRT for OLTs is tolerable. The LCR for OLTs from origins other than colorectal cancer is excellent. However, LCR for colorectal OLTs is worse than that from other origins. Therefore dose escalation should be considered to achieve good local control for colorectal OLTs.

Hypofractionated stereotactic radiotherapy with and without transarterial chemoembolization for small hepatocellular carcinoma not eligible for other ablation therapies: Preliminary results for efficacy and toxicity

Aim:  To investigate the efficacy and toxicity of hypofractionated stereotactic radiotherapy for the treatment of patients presenting with hepatocellular carcinoma (HCC) in a single institutional setting.

Acute exacerbation of subclinical idiopathic pulmonary fibrosis triggered by hypofractionated stereotactic body radiotherapy in a patient with primary lung cancer and slightly focal honeycombing

Hypofractionated stereotactic body radiotherapy (SBRT) for pulmonary lesions provides a high local control rate, allows completely painless ambulatory treatment, and is not associated with adverse reactions in most cases. Here we report a 70-year-old lung cancer patient with slight focal pulmonary honeycombing in whom subclinical idiopathic pulmonary fibrosis was exacerbated by SBRT. This experience has important implications for the development of selection criteria prior to SBRT for pulmonary lesions. For SBRT candidates with lung tumors, attention must be paid to the presence of co-morbid interstitial pneumonia even if findings are minimal. Such patients must be informed of potential risks, and careful decision-making must take place when SBRT is being considered.

Early graphical appearance of radiation pneumonitis correlates with the severity of radiation pneumonitis after stereotactic body radiotherapy (SBRT) in patients with lung tumors.

PURPOSE To investigate factors associated with Grade >or=3 radiation pneumonitis (RP) in patients with lung tumors treated with stereotactic body radiotherapy (SBRT). METHODS AND MATERIALS We retrospectively analyzed 128 patients with 133 lung tumors treated with SBRT. RP was graded according to the Common Terminology Criteria for Adverse Events version 3.0. Univariate analyses were used to identify predictive factors for RP. RESULTS The median follow-up period after SBRT was 12 months (range, 5-45 months). Incidences of Grades 0, 1, 2, and 3 RP were 27%, 52%, 16%, and 5%, respectively. No patients suffered Grade 4 or 5 RP. For all patients with Grade 2 or 3, symptoms occurred either simultaneously with or subsequent to graphical appearances. The latent period was the only significant factor associated with Grade >or=3 RP (p < 0.01). A latent period of 1 or 2 months indicated a 40% (6/15) risk for Grade 3. However, the risk for Grade 3 was 1.2% (1/82) 3 months after SBRT. No pretreatment clinical or dosimetric factors were significantly associated with Grade >or=3 RP. However, 4 of 7 patients with Grade 3 RP had severe pulmonary comorbidities. CONCLUSION Only the latency period was a significant factor in the development of RP. No pretreatment clinical or dosimetric factors were significantly associated with Grade >or=3 RP. Patients, especially those with severe pulmonary comorbidities, should be carefully observed for the graphical appearance of RP within a few months during the follow-up period after SBRT.

Comparison of clinical, tumour-related and dosimetric factors in grade 0–1, grade 2 and grade 3 radiation pneumonitis after stereotactic body radiotherapy for lung tumours

OBJECTIVE The aim of this study was to investigate significant clinical, tumour-related and dosimetric factors among patients with grade 0-1, grade 2 and grade 3 radiation pneumonitis (RP) after stereotactic body radiotherapy (SBRT) for lung tumours. METHODS Patients (n=128) with a total of 133 lung tumours treated with SBRT of 50 Gy in 5 fractions were analysed. RP was graded according to the Common Terminology Criteria for Adverse Events v.3.0. Significant factors were identified by univariate and multivariate analyses. Threshold dose-volume histograms (DVHs) were constructed to identify the incidence of RP. RESULTS The median follow-up period was 12 months (range, 6-45 months). In univariate analyses, gender, operability, forced expiratory volume in 1 s (FEV1), internal target volume, lung volumes treated with doses >5-30 Gy (V5-30) and mean lung dose were significant factors differentiating between grade 0-1 and grade 2 RP, and V15-30 were significant factors differentiating between grade 2 and grade 3. However, no factors were significant between grade 0-1 and grade 3 RP. Multivariate analysis showed that female gender, high FEV1 and high V15 were significant factors differentiating between grade 0-1 and grade 2 RP. Threshold DVH curves were created based on ≤5% and ≤15% risk of grade 2 RP among patients with grade 0-2 RP. CONCLUSIONS Grade 0-2 RP was dose-volume dependent, and female gender and high FEV1 were significant predictive clinical factors for grade 2 RP among patients with grade 0-2 RP. However, incidences of V15-30 in grade 3 RP were significantly lower than those in grade 2 RP, and no significant clinical or tumour-related factors were found. Further studies are needed to identify the mechanism underlying the development of grade 3 RP after SBRT for lung tumours.

Dose volume histogram analysis of focal liver reaction in follow-up multiphasic CT following stereotactic body radiotherapy for small hepatocellular carcinoma

PURPOSE To investigate threshold dose (TD) of focal liver reaction (FLR) following stereotactic body radiotherapy (SBRT) for patients with hepatocellular carcinoma (HCC) and liver cirrhosis. MATERIALS AND METHODS In consecutive 50 patients receiving SBRT for small HCC, 38 patients receiving SBRT and follow up >6 months, FLR on follow-up CT had been previously studied. Patients with good concordance between FLR and highly irradiated area were eligible. Dose volume histogram (DVH) was used to identify TDs for FLR. Clinical factors were analyzed for correlation with TDs. RESULTS Of 24 eligible patients, 23 had Child-Pugh score A and 1 scored B. Presence of FLR peaked at a median of 6 (range; 3-12) months. The median and 95% confidential intervals of TDs of pre-contrast and portal-venous phase CT were 32.4 Gy (30.3-35.4) and 34.4 Gy (31.9-36.0), respectively. Each median coefficient representing the concordance was 74.9% (range; 55.8-98.0%) and 80.5% (range; 70.8-92.4%), respectively. No clinical factors significantly correlated with the TDs. CONCLUSION We proposed 30 Gy/5 fractions as TD of FLRs following SBRT for patients with HCC and liver cirrhosis. This TD will enable us to predict injured liver volume and to avoid complication beforehand from toxicity. Further pathological and clinical studies, in addition to more practical and precise data of DVH, are needed to clarify the significance of FLRs.