title: Oligo-recurrence predicts favorable prognosis of brain-only oligometastases in patients with non-small cell lung cancer treated with stereotactic radiosurgery or stereotactic radiotherapy: a multi-institutional study of 61 subjects.
abstract: To investigate the prognostic value of oligo-recurrence in patients with brain-only oligometastases of non-small cell lung cancer (NSCLC) treated with stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT).
  
  
  
  Patients treated with SRS or SRT for brain-only NSCLC oligometastases in 6 high-volume institutions in Japan between 1996 and 2008 were reviewed. Eligible patients met 1), 2), and 4) or 1), 3), and 4) of the following: 1) NSCLC with 1 to 4 brain metastases on magnetic resonance imaging (MRI) treated with SRS or SRT; 2) control of the primary lesions (thorax) at the time of SRS or SRT for brain metastases (patients meeting this criterion formed the oligo-recurrence group); 3) with SRS or SRT for brain metastases, concomitant treatment for active primary lesions (thorax) with curative surgery or curative stereotactic body radiotherapy (SBRT), or curative chemoradiotherapy (sync-oligometastases group); and 4) Karnofsky performance status (KPS) ≥70.
  
  
  
  The median overall survival (OS) of all 61 patients was 26 months (95 % CI: 17.5-34.5 months). The 2-year and 5-year overall survival rates were 60.7 and 15.7 %, respectively. Stratified by oligostatus, the sync-oligometastases group achieved a median OS of 18 months (95 % CI: 14.8-21.1 months) and a 5-year OS of 0 %, while the oligo-recurrence group achieved a median OS of 41 months (95 % CI: 27.8-54.2 months) and a 5-year OS of 18.6 %. On multivariate analysis, oligo-recurrence was the only significant independent factor related to a favorable prognosis (hazard ratio: 0.253 (95 % CI: 0.082-0.043) (p = 0.025).
  
  
  
  The presence of oligo-recurrence can predict a favorable prognosis of brain-only oligometastases in patients with NSCLC treated with SRS or SRT.
authors.affiliation: Department of Radiology and Radiation Oncology, Kitasato University School of Medicine, 1-15-1, Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan. joe-n@hkg.odn.ne.jp.|Department of Radiology, Toho University Omori Medical Center, 6-11-1, Omori-nishi, Ota-ku, Tokyo, 143-8541, Japan. joe-n@hkg.odn.ne.jp.
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Niibe
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center, 1007, Monagakubo, Nagaizumi-cho, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nishimura
authors.affiliation: Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Kita 15-jo, Nishi 7-chome, Kita-ku, Sapporo, Hokkaido, 060-8638, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Department of Radiation Oncology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-18-22, Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Karasawa
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.|Ion Beam Therapy Center, SAGA-HIMAT Foundation, 415, Harukoga-cho, Tosu, Saga, 841-0071, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Shioyama
authors.affiliation: Department of Radiation Oncology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Jingu
authors.affiliation: Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Kita 15-jo, Nishi 7-chome, Kita-ku, Sapporo, Hokkaido, 060-8638, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shirato
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000532:radiotherapy* / Q000556:secondary*; D002289:Carcinoma, Non-Small-Cell Lung / Q000628:therapy*; D016371:Cranial Irradiation / Q000379:methods*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016634:Radiosurgery / Q000379:methods*; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
keywords: Non-small cell lung cancer (NSCLC); Oligo-recurrence; Oligometastases; Stereotactic radiosurgery (SRS); Stereotactic radiotherapy (SRT)