title: Selective lateral pelvic lymph node dissection in patients with advanced low rectal cancer treated with preoperative chemoradiotherapy based on pretreatment imaging.
abstract: BACKGROUND
  The significance of lateral pelvic lymph node (LPLN) metastasis in advanced low rectal cancer treated with preoperative chemoradiotherapy (CRT) remains unclear. The objective of this study was to evaluate the outcomes of selective LPLN dissection (LPLD) based on the pretreatment imaging in patients with advanced low rectal cancer treated with preoperative CRT.
  
  
  METHODS
  We reviewed 127 consecutive patients with clinical stage II-III low rectal cancer below the peritoneal reflection who underwent preoperative CRT and curative resection. LPLD was performed in patients with suspected LPLN metastasis based on MDCT or MRI before CRT (LPLD group, N = 38), and only total mesorectal excision (TME) was performed in patients without suspected LPLN metastasis (TME group, N = 89). Clinical characteristics and the oncological outcome were compared between groups.
  
  
  RESULTS
  The median tumor-to-anal verge distance was 40 mm in both groups. The median maximum long-axis LPLN diameter before CRT was 0 mm in the TME group and 10.5 mm in the LPLD group. Pathological LPLN metastasis was confirmed in 25 patients (66 %) in the LPLD group. Local recurrence at LPLN developed in 3 patients (3.4 %) in the TME group and in none (0 %) of the LPLD group. Multivariate analysis showed that only ypN was an independent prognostic factor for relapse-free survival (RFS), but LPLN metastasis was not associated with poor RFS.
  
  
  CONCLUSIONS
  The incidence of LPLN metastasis is high even after preoperative CRT, and LPLD might improve local control and survival of patients with LPLN metastasis in advanced low rectal cancer treated with preoperative CRT.
authors: Department of Gastroenterological Surgery, Gastroenterological Center, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan, takashi.akiyoshi@jfcr.or.jp.
authors: Takashi
authors: T
authors: Akiyoshi
authors: Masashi
authors: M
authors: Ueno
authors: Kiyoshi
authors: K
authors: Matsueda
authors: Tsuyoshi
authors: T
authors: Konishi
authors: Yoshiya
authors: Y
authors: Fujimoto
authors: Satoshi
authors: S
authors: Nagayama
authors: Yosuke
authors: Y
authors: Fukunaga
authors: Toshiyuki
authors: T
authors: Unno
authors: Atsuhiro
authors: A
authors: Kano
authors: Hiroya
authors: H
authors: Kuroyanagi
authors: Masatoshi
authors: M
authors: Oya
authors: Toshiharu
authors: T
authors: Yamaguchi
authors: Toshiaki
authors: T
authors: Watanabe
authors: Tetsuichiro
authors: T
authors: Muto
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000188:drug therapy / Q000401:mortality / Q000556:secondary / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D018279:Carcinoma, Signet Ring Cell / Q000188:drug therapy / Q000401:mortality / Q000556:secondary / Q000601:surgery; D059248:Chemoradiotherapy; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery; D009367:Neoplasm Staging; D010386:Pelvic Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D011300:Preoperative Care; D011379:Prognosis; D012004:Rectal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate