Background: This study aimed to investigate the prognostic value of tumor marker index (TMI) based on preoperative cytokeratin 19 fragment (CYFRA 21– 1) and squamous cell carcinoma antigen (SCC-Ag) and the relationship between preoperative TMI and treatment effectiveness of postoperative adjuvant chemotherapy for patients with esophageal squamous cell carcinoma (ESCC).
Patients and Methods: Between January 2009 and December 2014, a total of 267 patients with ESCC who underwent radical resection were retrospectively enrolled. The TMI was defined as the geometric mean of normalized CYFRA 21– 1 and SCC-Ag levels. The clinical and prognostic values of TMI were determined using univariate and multivariate survival analyses.
Results: Preoperative TMI level was associated with age, tumor size, pT stage, pN stage, and CYFRA 21– 1, SCC-Ag, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) levels. The 5-year overall survival rate of patients with high TMI was significantly lower than that of patients with low TMI (P < 0.001). Univariate and multivariate analyses revealed that TMI (P = 0.031) was an independent prognostic factor. Patients with ESCC with high TMI level who underwent surgery combined with postoperative chemotherapy had a significantly better prognosis than those who underwent surgery alone (P = 0.015). However, no significant difference was observed in patients with low TMI level (P = 0.682).
Conclusion: TMI as a prognostic indicator of ESCC is superior to CYFRA 21– 1 and SCC-Ag. The TMI might be useful in predicting the therapeutic effectiveness of postoperative chemotherapy and selecting patients who may benefit from postoperative chemotherapy.
Keywords: esophageal squamous cell carcinoma, CYFRA 21-1, SCC-Ag, tumor marker index, adjuvant chemotherapy