Effect of Responsiveness of Lymph Nodes to Preoperative Chemoradiotherapy in Patients With Rectal Cancer on Prognosis After Radical Resection

Hyun Gu Lee; Sung Joo Kim; In Ja Park; Seung Mo Hong; Seok-Byung Lim; Jung Bok Lee; Chang Sik Yu; Jin Cheon Kim

doi:10.1016/j.clcc.2019.03.001

Effect of Responsiveness of Lymph Nodes to Preoperative Chemoradiotherapy in Patients With Rectal Cancer on Prognosis After Radical Resection

Clin Colorectal Cancer. 2019 Jun;18(2):e191-e199. doi: 10.1016/j.clcc.2019.03.001. Epub 2019 Apr 1.

Authors

Hyun Gu Lee¹, Sung Joo Kim², In Ja Park³, Seung Mo Hong², Seok-Byung Lim⁴, Jung Bok Lee⁵, Chang Sik Yu⁴, Jin Cheon Kim⁴

Affiliations

¹ Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
² Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
³ Department of Colon and Rectal Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea. Electronic address: ipark@amc.seoul.kr.
⁴ Department of Colon and Rectal Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
⁵ Departments of Clinical Epidemiology and Biostatistics, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.

PMID: 31014994
DOI: 10.1016/j.clcc.2019.03.001

Abstract

Background: The influence of lymph node (LN) response to preoperative chemoradiotherapy (PCRT) has not been well evaluated for prognosis and additional use of adjuvant treatment after PCRT in rectal cancer patients. The aim of this study was to evaluate the prognostic effect of LN regression grade (LRG) in rectal cancer after PCRT and radical resection.

Patients and methods: From 2008 to 2011, 389 patients with rectal cancer treated with PCRT followed by radical resection were identified. The pathologic LRG (pLRG) score was determined on the basis of the proportion of tumor cells and fibrosis. The sum of the pLRG of each evaluated LN was used as the final LRG score, LRG-sum. Cox regression analysis was used to evaluate the association of LRG-sum and recurrence-free survival (RFS).

Results: The distribution of LRG-sum was significantly associated with tumor regression grade of the primary tumor (P < .001). LRG-sum showed different values even in patients with the same number of metastatic LNs. LRG-sum was confirmed as the most relevant associated factor among LN-related variables with RFS along with ypT stage in multivariate analysis. Patients were categorized according to the cutoff points of LRG-sum distribution: LRG1 (LRG-sum 0 to ≤3), LRG2 (LRG-sum 3 to ≤21), and LRG3 (LRG-sum >21). RFS showed a significant difference according to LRG group (P < .001) and showed more effective difference in RFS in the same ypN stage subgroup on the basis of the number of metastatic LNs.

Conclusion: LRG was a prognostic factor of oncologic outcomes of rectal cancer. LN response to PCRT might help in prognostication and determination of treatments after PCRT.

Keywords: Lymph nodes; Preoperative chemoradiotherapy; Prognosis; Rectal neoplasm; Response.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Chemoradiotherapy, Adjuvant / methods*
Disease-Free Survival
Drug Resistance, Neoplasm
Female
Humans
Kaplan-Meier Estimate
Lymph Nodes / diagnostic imaging
Lymph Nodes / drug effects
Lymph Nodes / radiation effects
Lymphatic Metastasis / diagnostic imaging
Lymphatic Metastasis / therapy*
Magnetic Resonance Imaging
Male
Middle Aged
Neoadjuvant Therapy / methods*
Neoplasm Recurrence, Local / epidemiology*
Neoplasm Recurrence, Local / pathology
Neoplasm Recurrence, Local / prevention & control
Neoplasm Staging
Proctectomy*
Prognosis
Radiation Tolerance
Rectal Neoplasms / diagnostic imaging
Rectal Neoplasms / mortality
Rectal Neoplasms / therapy*
Retrospective Studies