Predicting patterns of failure in esophageal cancer following tri-modality therapy: Why histology matters

Abstract

4553 Background: This analysis was performed to determine the impact of histology on pathologic complete response (pCR) and failure patterns for patients with esophageal cancer undergoing neo-adjuvant chemo-radiation followed by surgical resection. Methods: Between 1992–2006, 164 pts. underwent tri-modality therapy for esophageal cancer. The median RT dose was 50.4Gy. Pts. received Cisplatin/5-Fluorouracil for 2 cycles during RT. Pts. were taken to surgery at a median of 7 weeks. Overall survival (OS), disease free survival (DFS), and loco-regional control (LRC) were calculated using the Kaplan-Meir product method. Results: The median follow-up was 18 months and 27 months in surviving pts. There were 68% with adenocarcinoma (AC) and 32% with squamous cell (SCC). A pCR rate was seen in 41.4%. PCR was achieved in 35% with AC and 54% with SCC (p - 0.01). Forty one percent died due to recurrent disease. Of the failures, 66% were distant, 21% were loco-regional, 9% were loco-regional and distant, and 3% were found to have progressed at the time of resection. Of the distant failures, the first site of failure was the liver in 40%, the lungs in 16%, the bones in 20%, and the para-aortic nodes in 4%. Of the AC’s with recurrence, 39% failed locally, and 68% failed distantly. Of the SCC with recurrence, there were no local failures and 100% failed distantly (p-.001). The three year LRC for AC and SCC was 71% and 100% (p=0.03). On multivariate analysis histology predicted for pCR and improved LRC (p=0.001). The median OS and DFS was 27 months and 20 months. Median OS and DFS of AC with a pCR versus no pCR was 70 months and 59 months versus 26 months and 13 months (p=0.01). Median OS and DFS of SCC with a pCR versus no pCR was 44 months and 41 months versus 18 months and 14 months (p=0.33). Conclusions: This data reveals that esophageal cancer outcomes are predicted by histology. AC’s with complete pathologic response have excellent long term disease free outcomes. Although, SCC is associated with a higher rate of pCR, it is not associated with significantly improved disease free outcomes. Furthermore, SCC’s have a higher likelihood for developing distant metastasis and are at a relatively low risk of failing loco-regionally. This data highlights the need for improved systemic control in this subgroup of patients. No significant financial relationships to disclose.