P2.04-031 Predictors of Pathological Complete Response (TRG=1) among Esophageal Cancer Cases; NCI Pooled Data: Topic: Esophageal Cancer and Other Malignancies

Abstract

Commonly used chemotherapy regimens for esophageal cancer (EC) are EOX(Epirubicin/Oxaloplatin/Capecitabine) for adenocarcinoma and CF(Cisplatin and 5-Fluorouracil) for squamous carcinoma. In this study we aim to assess prevalence of pathological complete response (pCR) after current chemotherapeutic regimens among our EC cases and compare pCR cases to the remaining cohort. We retrospectively reviewed Pathology Department database to retrieve EC patients treated in our National Cancer Institute (NCI), Cairo University during the past 5-years. Available variables were age, gender, operation, diagnosis, tumor size and grade, LN-size, presence of Barrett’s esophagus or in-situ/micro-invasive carcinoma, gross and microscopic pictures. MANDARD’s pathological response using tumor regression grade (TRG) was quantitated into five grades (1-5) with TRG=1 showing absence of residual cancer (Mandard et al.,1994. Esophageal carcinoma regression after chemoradiotherapy, Cancer,73(11),2680-86). Logistic regression was used to identify pCR(TRG-1)predictors. Kaplan-Meier survival curves were used. 334 patients were encountered with males predominance; 202 (60.5%), Median age was 64(Inter-quartile range;IQR;58-68), Pathology was SqCC in 227 (68%), adenocarcinoma in 94 (28.1%), undifferentiated ca in 9 (2.7%)and others in 4 (1.2%). pCR (TRG-1) was evident in 15 cases (4.5%). Among mentioned variables, only advanced age, non SqCC and high grade tumors adversely affect pathological response to induction treatment. On MVA, Advanced age (Odd Ratio (OR)=0.923, 95%Confidence interval (CI)=0.86-0.99) p=0.025), moderate/high grade tumors(OR=0.03, p<0.001)adversely affect response while SqCC pathology has better response trend(OR4.39, p=0.086). 3-years overall survival (OS) was 100% in pCR (TRG-1) vs 82.3% in the remaining cohort (Figure). Among esophagectomy cases, surgery was done in 71.7% males vs28.3% females (p=0.093). Gastric pull up was performed in all surgical cases. R1 was present in 2.2%. Median tumor size was 4.3cm (IQR;3-5.6cm), least surgical margin was 3 (2-4) and max (LN) size was 1(1-2cm).Median +veLN, total LNnumber&LN-ratio was 0 (0-1), 10 (7-17) and 0 (0-5%) respectively. 30-days-perioperative mortality was 6.5%. 3 years OS among esophagectomy patients was 79.6%. Young EC patients and low grade tumor show better response to chemotherapy so aggressive treatment is warranted among this cohort. SqCC carries a good prediction to pathological response and hence better survival mandating aggressive chemo-radiation in this cohort aiming to cure.