title: Neoadjuvant chemoradiotherapy affects the indications for lateral pelvic node dissection in mid/low rectal cancer with clinically suspected lateral node involvement: a multicenter retrospective cohort study.
abstract: BACKGROUND
  Although lateral pelvic node dissection (LPND) is recommended for rectal cancer with clinically metastatic lateral pelvic lymph nodes (LPNs), LPNs may respond to neoadjuvant chemoradiotherapy (nCRT). Our aim was to determine the optimal indication for LPND after nCRT for mid/low rectal cancer.
  
  
  METHODS
  Of 2,263 patients with clinical stage II/III mid/low rectal cancer who were managed at three tertiary referral hospitals, 66 patients underwent curative surgery including LPND after nCRT were included in this study. Risk factors for LPN metastasis were retrospectively analyzed and oncologic outcomes determined according to LPN response to nCRT.
  
  
  RESULTS
  Persistent LPNs greater than 5 mm on post-nCRT magnetic resonance imaging were significantly associated with residual tumor metastasis, unlike responsive LPN after nCRT (short-axis diameter ≤ 5 mm) (pathologically, 61.1 % [22 of 36] vs. 0 % [0 of 30], P < 0.001). Multivariable analysis revealed post-nCRT LPN size as a significant and independent risk factor for LPN metastasis (odds ratio 2.390; 95 % confidence interval 1.104-4.069). Over a median follow-up of 39.3 months, the recurrence rate was lower in patients with responsive nodes than in patients with persistent nodes (20 % [6 of 30] vs. 47.2 % [17 of 36], P = 0.012). The 5-year overall survival and 5-year disease-free survival rates were lower in patients with persistent LPN than in patients with responsive LPN (44.6 % vs. 77.1 %, P = 0.034; 33.7 % vs. 72.5 %, P = 0.011, respectively).
  
  
  CONCLUSIONS
  In mid/low rectal cancer with clinically metastatic LPNs, the decision to perform LPND should be based on the LPN response to nCRT.
authors.affiliation: Department of Surgery, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Heung-Kwon
authors.initials: HK
authors.lastname: Oh
authors.forename: Sung-Bum
authors.initials: SB
authors.lastname: Kang
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Myoung Hun
authors.initials: MH
authors.lastname: Ihn
authors.forename: Duck-Woo
authors.initials: DW
authors.lastname: Kim
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Park
authors.forename: Young Hoon
authors.initials: YH
authors.lastname: Kim
authors.forename: Kyung Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Kim
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Kim
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Tae-Young
authors.initials: TY
authors.lastname: Chang
authors.forename: Sung-Chan
authors.initials: SC
authors.lastname: Park
authors.forename: Dae Kyung
authors.initials: DK
authors.lastname: Sohn
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Oh
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Park
authors.forename: Seung-Bum
authors.initials: SB
authors.lastname: Ryoo
authors.forename: Seung-Yong
authors.initials: SY
authors.lastname: Jeong
authors.forename: Kyu Joo
authors.initials: KJ
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000628:therapy; D009367:Neoplasm Staging; D010386:Pelvic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000628:therapy; D011300:Preoperative Care; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate