title: Partial-brain radiotherapy for primary central nervous system lymphoma: multi-institutional experience.
abstract: Whole-brain radiotherapy (WBRT) has been an important component of treatment for primary central nervous system lymphoma (PCNSL), but delayed neurotoxicity has been a matter of concern. We have employed partial-brain radiotherapy (PBRT) with wide margins for PCNSL patients with a single lesion or a few lesions. In this study, we evaluated the treatment outcome in PCNSL patients undergoing PBRT. Between 2003 and 2014, 24 patients were treated with PBRT; 16 received high-dose-methotrexate (MTX) -containing chemotherapy before PBRT. Conventional fractionation with a median dose of 54 Gy was used. For reference, 15 patients undergoing MTX-based chemotherapy and WBRT were also analyzed. The 3-year overall survival rate was 60% for all 24 patients undergoing PBRT and 68% for the 16 patients undergoing MTX-based chemotherapy plus PBRT. The 3-year progression-free survival rate was 41% for all 24 patients undergoing PBRT and 36% for the 16 patients undergoing MTX-based chemotherapy. The in-field recurrence rate was 26% and the out-of-field recurrence rate was 15% at 3 years for all 24 patients undergoing PBRT. The rates for in-field recurrence and the out-of-field recurrence were 27% and 21%, respectively, for the 16 patients undergoing MTX-based chemotherapy. CNS-recurrence rates were similar in patients undergoing MTX-based chemotherapy and PBRT to the rates in those undergoing MTX-based chemotherapy and WBRT. Neurocognitive dysfunction developed in 3 of the 16 patients undergoing MTX + PBRT and in 4 of 15 patients undergoing MTX + WBRT (P = 0.68). PBRT seems to be a feasible treatment option for solitary PCNSL. Further investigations are warranted to evaluate the advantages of PBRT over WBRT.
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan m.iwabuchi0628@gmail.com.
authors.forename: Michio
authors.initials: M
authors.lastname: Iwabuchi
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Shibamoto
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Chikao
authors.initials: C
authors.lastname: Sugie
authors.affiliation: Japan Community Healthcare Organization Chukyo Hospital, 1-1-10 Sanjyou, Minami-ku, Nagoya, Aichi, 457-8510, Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Ayakawa
authors.affiliation: Nagoya Proton Therapy Center, 1-1-1 Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ogino
authors.affiliation: Nagoya City West Medical Center, 1-1-1 Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan.
authors.forename: Fumiya
authors.initials: F
authors.lastname: Baba
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000528:radiation effects*; D016543:Central Nervous System Neoplasms / Q000532:radiotherapy*; D018572:Disease-Free Survival; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008223:Lymphoma / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D055815:Young Adult
keywords: PCNSL; neurocognitive function; partial-brain radiotherapy; primary central nervous system lymphoma; radiation therapy