title: Survival implications of pretreatment pelvic CT in rectal cancer patients after neoadjuvant chemoradiotherapy and surgery.
abstract: OBJECTIVE
  To determine the correlation between pretreatment computed tomography (CT) data and survival duration after neoadjuvant chemoradiotherapy and surgery for locally advanced rectal cancer.
  
  
  METHODS
  122 consecutive patients with advanced rectal cancer were assessed retrospectively. Pretreatment imaging and postoperative data were evaluated through Kaplan-Meier and Cox proportional hazard regression analyses.
  
  
  RESULTS
  Pretreatment CT identified 557 metastatic lymph nodes (mean, 4.55 per patient; median 4). Survival durations were measured during the period between the application of CT and death or the last follow-up examination. Univariate analysis showed that the following factors had a significant impact on survival: maximum tumor diameter (P = 0.019), distance from inferior tumor margin to anorectal ring (P <0.0001), number of lymph nodes involved in patients with short-axis, lymph node diameter ≥8 mm (P <0.0001) in pretreatment CT, distance from the anorectal ring (P = 0.027), ypN stage (P = 0.0008), ypM stage (P = 0.046) and number of metastatic lymph nodes (P <0.0001) in clinical assessment. Multivariate analysis showed that the following factors were significant: number of lymph nodes in patients with short-axis lymph node diameter ≥5 mm but <8 mm (P = 0.044) and in those with this diameter ≥8 mm (P = 0.028; pretreatment CT) and number of metastatic lymph nodes (assessed in histopathological examination).
  
  
  CONCLUSIONS
  Pretreatment lymph node size and number can predict survival duration after treatment for locally advanced rectal cancer. For patients with lymph nodes >8 mm (short-axis diameter) and/or >1, such lymph nodes tend to have a poor performance for prognosis.
authors.affiliation: Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine 651 Dongfeng Road East, Guangzhou 510060, People's Republic of China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Cui
authors.affiliation: Department of Radiology, The People's Hospital of Laiwu Laiwu 271100, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine 651 Dongfeng Road East, Guangzhou 510060, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Tian
authors.affiliation: Department of Colorectal Surgery, Sun Yat-sen University Cancer Center Guangzhou, People's Republic of China.
authors.forename: Wu
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Radiation Oncology, Sun Yat-sen University Cancer Center Guangzhou, People's Republic of China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine 651 Dongfeng Road East, Guangzhou 510060, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
keywords: Locally advanced rectal cancer; lymph node size; multislice spiral CT; survival