title: Low Prognostic Nutritional Index (PNI) Predicts Unfavorable Distant Metastasis-Free Survival in Nasopharyngeal Carcinoma: A Propensity Score-Matched Analysis.
abstract: BACKGROUND
  Poor nutritional status is associated with progression and advanced disease in patients with cancer. The prognostic nutritional index (PNI) may represent a simple method of assessing host immunonutritional status. This study was designed to investigate the prognostic value of the PNI for distant metastasis-free survival (DMFS) in patients with nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  A training cohort of 1,168 patients with non-metastatic NPC from two institutions was retrospectively analyzed. The optimal PNI cutoff value for DMFS was identified using the online tool "Cutoff Finder". DMFS was analyzed using stratified and adjusted analysis. Propensity score-matched analysis was performed to balance baseline characteristics between the high and low PNI groups. Subsequently, the prognostic value of the PNI for DMFS was validated in an external validation cohort of 756 patients with NPC. The area under the receiver operating characteristics curve (AUC) was calculated to compare the discriminatory ability of different prognostic scores.
  
  
  RESULTS
  The optimal PNI cutoff value was determined to be 51. Low PNI was significantly associated with poorer DMFS than high PNI in univariate analysis (P<0.001) as well as multivariate analysis (P<0.001) before propensity score matching. In subgroup analyses, PNI could also stratify different risks of distant metastases. Propensity score-matched analyses confirmed the prognostic value of PNI, excluding other interpretations and selection bias. In the external validation cohort, patients with high PNI also had significantly lower risk of distant metastases than those with low PNI (Hazards Ratios, 0.487; P<0.001). The PNI consistently showed a higher AUC value at 1-year (0.780), 3-year (0.793) and 5-year (0.812) in comparison with other prognostic scores.
  
  
  CONCLUSIONS
  PNI, an inexpensive and easily assessable inflammatory index, could aid clinicians in developing individualized treatment and follow-up strategies for patients with non-metastatic NPC.
authors.affiliation: Sun Yat-sen University cancer center, Guangzhou, China.|State Key Laboratory of Oncology in Southern China, Guangzhou, China.|Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Lin
authors.identifier: http://orcid.org/0000-0002-5550-3698
authors.initials: L
authors.lastname: Yang
authors.affiliation: Sun Yat-sen University cancer center, Guangzhou, China.|State Key Laboratory of Oncology in Southern China, Guangzhou, China.|Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Liangping
authors.initials: L
authors.lastname: Xia
authors.affiliation: Sun Yat-sen University cancer center, Guangzhou, China.|State Key Laboratory of Oncology in Southern China, Guangzhou, China.|Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Sun Yat-sen University cancer center, Guangzhou, China.|State Key Laboratory of Oncology in Southern China, Guangzhou, China.|Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Shaodong
authors.initials: S
authors.lastname: Hong
authors.affiliation: The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Chen
authors.affiliation: The First Hospital of Foshan, Foshan, China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Liang
authors.affiliation: The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China.
authors.forename: Peijian
authors.initials: P
authors.lastname: Peng
authors.affiliation: Sun Yat-sen University cancer center, Guangzhou, China.|State Key Laboratory of Oncology in Southern China, Guangzhou, China.|Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000175:diagnosis* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D009362:Neoplasm Metastasis; D015596:Nutrition Assessment; D057216:Propensity Score; D012189:Retrospective Studies