The predictive value of histological tumor regression grading (TRG) for therapeutic evaluation in locally advanced esophageal carcinoma treated with neoadjuvant chemotherapy

Abstract

Response criteria remain controversial in therapeutic evaluation for locally advanced esophageal carcinoma treated with neoadjuvant chemotherapy. We aimed to identify the predictive value of tumor regression grading (TRG) in tumor response and prognosis. Fifty-two patients who underwent neoadjuvant chemotherapy followed by esophagectomy and radical 2-field lymphadenectomy between June 2007 and June 2011 were included in this study. All tissue specimens were reassessed according to the TRG scale. Potential prognostic factors, including clinicopathologic factors, were evaluated. Survival curves were generated by using the Kaplan-Meier method and compared with the log-rank test. Prognostic factors were determined with multivariate analysis by using the Cox regression model. Our results showed that of 52 cases, 43 (83%) were squamous cell carcinoma and 9 (17%) were adenocarcinoma. TRG was correlated with pathologic T(P = 0.006) and N (P < 0.001) categories. Median overall survival for the entire cohort was 33 months. The 1- and 2-year overall survival rates were 71% and 44%, respectively. Univariate survival analysis results showed that favorable prognostic factors were histological subtype (P = 0.003), pathologic T category (P = 0.026), pathologic N category (P < 0.001), and TRG G0 (P = 0.041). Multivariate analyses identified pathologic N category (P < 0.001) as a significant independent prognostic parameter. Our results indicate that histomorphologic TRG can be considered as an alternative option to predict the therapeutic efficacy and prognostic factor for patients with locally advanced esophageal carcinoma treated by neoadjuvant chemotherapy.

Figure 1.. Kaplan-Meier overall survival curves for patients with locally advanced esophageal carcinoma of different tumor regression grades (TRG).

The difference between groups (G0, n = 9; G1, n = 20; G3, n = 23) was compared with the log-rank test. The survival rate of the was significantly higher in G0 group than in other groups (P = 0.041).

Figure 2.. Kaplan-Meier overall survival curves for patients with locally advanced esophageal carcinoma of different types.

The difference between tumor types (squamous carcinoma, n = 43; adenocarcinoma, n = 9) was compared with the log-rank test. The survival rate was significantly higher in patients with squamous cell carcinoma than in those with adenocarcinoma (P = 0.003).

Figure 3.. Kaplan-Meier overall survival curves for patients with locally advanced esophageal carcinoma at different locations.

The difference between tumor locations (upper esophagus, n = 6; middle esophagus, n = 30; lower esophagus, n = 9; gastroesophageal junction, n = 7) was compared with the log-rank test. The survival rate was significantly higher in upper esophagus group than in other groups (P = 0.044).

Figure 4.. Kaplan-Meier overall survival curves for patients with locally advanced esophageal carcinoma of different pathologic T stage after neoadjuvant chemotherapy.

The difference between groups (T0, n = 6; T1, n = 5; T2, n = 11; T3, n = 30) was compared with the log-rank test. The survival rate was significantly higher in T0 group than in other groups (P = 0.026).

Figure 5.. Kaplan-Meier overall survival curves for patients with locally advanced esophageal carcinoma of different pathologic N stage after neoadjuvant chemotherapy.

The difference between groups (N0, n = 21; N1, n = 11; N2, n = 8; N3, n = 8) was compared with the log-rank test. The survival rate was significantly higher in N0 group than in other groups (P < 0.001).