Comparison of neoadjuvant chemoradiation with carboplatin/ paclitaxel or cisplatin/ 5-fluoruracil in patients with squamous cell carcinoma of the esophagus

Neoadjuvant chemoradiation (nCRT) is the treatment of choice for patients with locally advanced squamous cell carcinoma of the esophagus (SCC). Today radiation oncologists can choose between two different therapy regimes including chemoradiation with cisplatin and 5-fluoruracil (CDDP/5FU) and chemoradiation analogue to the CROSS-regime with carboplatin and paclitaxel (Carb/TAX). However, there is a lack of studies comparing these regimes, especially for the subgroup of patients with SCC. In this study, we want to compare nCRT with CDDP/5FU and nCRT with Carb/TAX for patients with locally advanced SCC.

We retrospectively compared 20 patients who were scheduled for nCRT with a total radiation dose of 41.4 Gy (daily dose of 1.8 Gy) and weekly chemotherapy with carboplatin (Area under the curve 2) and Paclitaxel (50 mg per square meter of body-surface area) according to the CROSS-regime to 31 patients who were scheduled for nCRT with a total radiation dose of 45 Gy (daily dose of 1.8 Gy) and simultaneous chemotherapy with cisplatin (20 mg/m²/d) and 5-fluoruracil (500 mg/m²/d) on day 1–5 and day 29–33. For the per-protocol (PP) analysis, per protocol treatment was defined as either complete radiation with 41.4 Gy, at least three complete cycles of Carb/TAX and subsequent surgery or complete radiation with 45 Gy, at least one complete cycle of CDDP/5FU and subsequent surgery.

Fifty-one patients (31 patients treated with CDDP/5FU and 20 patients treated with Carb/TAX) were evaluated for the intention-to-treat (ITT) analysis and 44 patients (26 patients treated with CDDP/5FU and 18 patients treated with Carb/TAX) were evaluated for the PP analysis. No significant differences were seen for baseline and tumor characteristics like age, sex, TNM-stage, grading and tumor extension between patients treated with Carb/TAX and patients treated with CDDP/5FU. The most common tumor regression grade after nCRT was grade I as classified by Becker et al., which was observed in 84 and 79% of patients. No significant differences in tumor regression grades were seen between both regimes. Postoperative insufficiency of the anastomosis was seen in 6 patients (33%) who were treated with Carb/TAX and 4 patients (15%) who were treated with CDDP/5FU (p = 0.273). Patients treated with CDDP/5FU developed significantly more cumulative hematologic III° (CTCAE) toxicities (58% vs 20%; p = 0.010) than patients treated with Carb/TAX. In contrast to that, there was no significant difference for overall survival (OS) and freedom from relapse (FFR) between treatment groups.

In this retrospective analysis, no significant difference was seen for OS and FFR between nCRT with CDDP/5FU and nCRT with Carb/TAX. However, the application of CDDP/5FU was associated with significantly more hematologic III°- toxicities compared to Carb/TAX. Future prospective trials should investigate if these results are reproducible in randomized patient cohorts.