title: Impact of microscopic orbital periosteum invasion in orbital preservation surgery.
abstract: OBJECTIVE
  The orbital periosteum is considered to be a barrier to tumor spread; however, it is difficult to evaluate microscopic tumor spread during surgery. This study aimed to assess the impact of pathological status in orbital preservation surgery.
  
  
  METHODS
  We retrospectively analyzed the 3-year local control rate and treatment outcomes of patients with malignant tumors invading the orbit who were treated between 2006 and 2012.
  
  
  RESULTS
  In total, 27 patients were reviewed over a median follow-up period of 36 months. Pathologically, 19 had carcinomas and 8 had sarcomas. Treatment was by orbital exenteration in 6 patients and orbital preservation surgery in 21 patients. After orbital preservation surgery, poorer 3-year local control rates were significantly associated with positive surgical margins (negative vs. positive: 91% vs. 41%, P = 0.040) and microscopic orbital periosteum invasion (negative vs. positive: 90% vs. 39%, P = 0.010). These factors were independent risk factors in multivariate analysis. The locations of the positive margin were most common at the horizontal and vertical margins of the orbital periosteum and the posterior margin of the orbital apex. Moreover, in 24% of patients, invasion evaluation by preoperative imaging study was underestimated compared with postoperative microscopic evaluation.
  
  
  CONCLUSIONS
  The positive surgical margin and microscopic orbital periosteum invasion were the risk factors of orbital recurrence. It is difficult to determine the indications for orbital preservation surgery by preoperative imaging studies because of the unpredictable accurate pathological status before surgery and the limitations of preoperative imaging evaluation.
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Kenya
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Pathology, National Cancer Center Hospital, Tokyo.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Mori
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Matsumoto
authors.affiliation: Department of Radiation oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Naoya
authors.initials: N
authors.lastname: Murakami
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Masanori
authors.initials: M
authors.lastname: Teshima
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Fukasawa
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Satoko
authors.initials: S
authors.lastname: Matsumura
authors.affiliation: Department of Radiation oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Jun
authors.initials: J
authors.lastname: Itami
authors.affiliation: Department of Otolaryngology, Kamagaya General Hospital, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Asai
authors.affiliation: Department of Head and Neck Oncology, National Cancer Center Hospital, Tokyo.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Yoshimoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009915:Orbit / Q000601:surgery*; D010521:Periosteum / Q000002:abnormalities / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: carcinoma; orbit invasion; periosteum; preservation surgery; sarcoma