A province-wide retrospective comparison of pathologic response and progression-free survival in locally advanced esophagus cancer patients treated with either cisplatin-5FU (CF) or carboplatin-paclitaxel (CP) concurrent with radiation (XRT) with or without surgery.

Abstract

107 Background: The 2012 CROSS trial demonstrated an overall survival (OS) benefit for neoadjuvant, concurrent Carboplatin-Paclitaxel (CP) and radiation versus surgery alone. Based on this trial, the standard chemotherapy treatment for locally advanced esophageal (LAE) cancer in British Columbia (BC) became CP instead of Cisplatin-5FU (CF). This study evaluates the pCR rates and progression free survival (PFS) of those patients treated immediately prior and immediately after the change in provincial standard. Methods: All BC patients with LAE cancer diagnosed between February 2010 and February 2013 who completed at least 40 Gy of neoadjuvant radiation were analyzed. Standard demographics, chemotherapy delivered, radiation dose, surgical pathology and follow-up data were collected. Pathologic response was compared by chi-squared analysis. Patients were followed until death or last follow-up. Survival was compared by log-rank test. Results: Seventy-three patients received CF and 39 received CP. The tumor characteristics of the subgroups were similar: squamous histology was 57% (CF) vs. 49% (CP), node positivity rate on pre-treatment PET scan was 66 vs. 67%, and median tumor length was 5.7 vs. 5.8 cm. Median radiation dose was 50 Gy in both arms. The CP arm was slightly older (Median 66 vs. 61 yo) and had a greater percentage of males (80% vs. 57%). Forty eight and 49% percent of patients were able to undergo resection. The pCR rates were 49% (CF) vs. 16% (CP) (p<0.01) in the surgical subgroups. Median FU was 14.5 (CF) vs. 9.3 (CP) months. Median PFS for all patients was 16.5 (CF) and 14.6 (CP) (p=0.44). Median PFS in surgical patients was 23.4 months (CF) and 14.6 months (CP) (p=0.16. Conclusions: In patients with similar tumor characteristics, XRT with CF resulted in greater pCR rates than with CP. The pCR rate in the CP subgroup is lower than the 29% seen in the trial. With relatively short follow-up, no difference in PFS has yet been identified. [Table: see text]