title: Factors affecting the risk of brain metastasis in small cell lung cancer with surgery: is prophylactic cranial irradiation necessary for stage I-III disease?
abstract: OBJECTIVE
  The use of prophylactic cranial irradiation (PCI) in small cell lung cancer (SCLC) with surgical resection has not been fully identified. This study undertook to assess the factors affecting the risk of brain metastases in patients with stage I-III SCLC after surgical resection. The implications of PCI treatment for these patients are discussed.
  
  
  METHODS
  One hundred twenty-six patients treated with surgical resection for stage I-III SCLC from January 1998-December 2009 were retrospectively analyzed to elucidate the risk factors of brain metastases. Log-rank test and Cox regression model were used to determine the risk factors of brain metastases.
  
  
  RESULTS
  The median survival time for this patient population was 34 months, and the 5-year overall survival rate was 34.9%. For the whole group, 23.0% (29/126) of the patients had evidence of metastases to brain. Pathologic stage not only correlated with overall survival but also significantly affected the risk of brain metastases. The 5-year survival rates for patients with pathologic stages I, II, and III were 54.8%, 35.6%, and 14.1%, respectively (P=.001). The frequency of brain metastases in patients with pathologic stages I, II, and III were 6.25% (2/32), 28.2% (11/39), and 29.1% (16/55) (P=.026), respectively. A significant difference in brain metastases between patients with complete resection and incomplete resection was also observed (20.5% vs 42.9%, P=.028). The frequency of brain metastases was not found to be correlated with age, sex, pathologic type, induction chemotherapy, adjuvant chemotherapy, or adjuvant radiation therapy.
  
  
  CONCLUSIONS
  Stage I SCLC patients with complete resection had a low incidence of brain metastases and a favorable survival rate. Stage II-III disease had a higher incidence of brain metastases. Thus, PCI might have a role for stage II-III disease but not for stage I disease.
authors: Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China.
authors: Linlin
authors: L
authors: Gong
authors: Q I
authors: QI
authors: Wang
authors: Lujun
authors: L
authors: Zhao
authors: Zhiyong
authors: Z
authors: Yuan
authors: Ruijian
authors: R
authors: Li
authors: Ping
authors: P
authors: Wang
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000453:epidemiology / Q000517:prevention & control* / Q000556:secondary; D016371:Cranial Irradiation; D005260:Female; D006801:Humans; D015994:Incidence; D060828:Induction Chemotherapy / Q000379:methods; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012306:Risk; D055752:Small Cell Lung Carcinoma / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control* / Q000556:secondary / Q000601:surgery*; D015996:Survival Rate