title: Hippocampus-Sparing Whole-Brain Radiotherapy and Simultaneous Integrated Boost for Multiple Brain Metastases From Lung Adenocarcinoma: Early Response and Dosimetric Evaluation.
abstract: In this study, the volume response and treatment outcome after hippocampus-sparing whole-brain radiotherapy (HS-WBRT) with simultaneous integrated boost (SIB) using tomotherapy were evaluated. Patients with primary lung adenocarcinoma and multiple brain metastases who had a Karnofsky performance status ≥ 70 and exhibited well-controlled extracranial disease were treated. The prescribed dose was administered in 10 to 14 fractions as 25 to 28 Gy to whole-brain parenchyma, as 40 to 48 Gy to the gross metastatic lesion, and as 30 to 42 Gy to a 5-mm margin to the metastatic lesion. Double-dose gadolinium contrast-enhanced magnetic resonance imaging at 1-mm slice thickness was performed before treatment and at 1, 4, and 7 months post-treatment. The tumor volume reduction ratio was calculated for each follow-up. Between July 2011 and September 2012, 11 patients with 70 lesions were included in this analysis. The median number of lesions per patient was 4 (range, 2-15). The median initial tumor volume was 0.235 cm(3) (range, 0.020-10.140 cm(3)). The treatment plans were evaluated regarding conformation number (CN), target coverage (TC), and homogeneity index (HI). The median follow-up duration was 14 months (range, 3-25 months) and the 1-year intracranial control rate was 67%. The tumor volume reduction was most prominent during the first month with a median reduction rate of 0.717 (range, -0.190 to 1.000). Complete remission was seen in 22 (33%) lesions, and 45 (64%) lesions showed more than 65% reduction in tumor volume. The CN, TC, and HI values were comparable to that of previous studies, and the mean hippocampal dose was 13.65 Gy. No treatment breaks or ≥ G3 acute toxicities were observed during or after treatment. The HS-WBRT with SIB in patients with multiple brain metastases was effective and feasible for volume reduction and showed excellent intracranial control.
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Byoung Chul
authors.initials: BC
authors.lastname: Cho
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chang Geol
authors.initials: CG
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hye Ryun
authors.initials: HR
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yang Gun
authors.initials: YG
authors.lastname: Suh
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jun Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chihwan
authors.initials: C
authors.lastname: Choi
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jong Geal
authors.initials: JG
authors.lastname: Baek
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea jjhmd@yuhs.ac.
authors.forename: Jaeho
authors.initials: J
authors.lastname: Cho
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D059351:Organ Sparing Treatments; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies; D016896:Treatment Outcome; D047368:Tumor Burden / Q000528:radiation effects
keywords: brain metastasis; hippocampus; lung adenocarcinoma; radiotherapy; tumor volume