Introduction: The standard treatment for patients (pts) with locally advanced esophageal carcinoma (LAEC) and good performance status is preoperative chemoradiotherapy followed by surgery. The two main histologic subtypes, adenocarcinoma (ADC) and squamous cell carcinoma (SCC) present different epidemiology and might differ in prognosis. Our aim is to analyze the outcomes of a cohort of patients treated in our center and compare both histologies.
Methods: We reviewed 100 patients (pts) diagnosed with primary LAEC that were treated with concurrent CRT followed by surgery at the Catalan Institute of Oncology, Bellvitge Hospital and integrated centers between 2000-2014. All pts were discussed at the multidisciplinary Gastroesophageal Tumors Functional Unit (UTEG). We described clinical characteristics, recurrence rates and survival curves using Kaplan Meier. A multivariate Cox regression was performed to identify prognostic factors.
Results: 100 pts were studied: mean age 61 (34-78); 93% male; 96% PS ≤ 1; 18% Barrett esophagus; 42/43/15% Active/Former/Never smokers; Histology: 50% ADC/ 42% SCC, 2% undifferentiated. Location: 82% esophagus (7/35/40% upper, middle, lower) and 18% esophagogastric junction (Siewert I and II). Clinical stage included cT2N + , cT3-4a-b N0/+. 88% were node positive (cN+). 96% pts received a median of 2 cycles of NA CT, being the most used regimen CDDP-5FU (83%). Total RT dose received was 45 Gy (76%) and 50,4Gy (18%), depending on the centre protocol. G3/G4 toxicity occurred in 18% pts. Radiological response was assessed by PET: 19% complete response (CR), 55% partial response (PR), 16% stable disease (SD), 7% progression (PD), 3% not determined (ND). 83 pts (83%) underwent surgery: ADC 53%, SCC 40%. 83% R0. Pathologic complete response (ypT0N0-ypCR) was achieved in 20 pts (24%): 39% ADC/61% SCC. Downstaging of cN+ to ypN0 was 61% (44/72 pts). Deaths due to post-operative complications (within 30 days) occurred in 2 patients (2,8%). After a median follow-up of 26 months (m), overall recurrence rate (ORR) of pts who underwent surgery was 43% (36 pts): 58% of resected ADC, 33% of resected SCC. Median time to recurrence disease (mTRD) for ADC was 16,5m vs SCC, not reached (p < 0,24). 1 and 3 years RR was 36% and 43%, respectively. Median overall survival (OS) was 32 m (IC 95% 14,1-49,3): 26,8m ADC vs 45,4m SCC (p < 0,001). 1 and 3 years OS rate were 66% and 53%, respectively. In the multivariate Cox regression, two independent factors influenced in OS: ypCR HR 0,5 (0,19-1,25) (p< 0,016) and ypN+ HR 2,3 (1,1-4,8) (p< 0,001).
Conclusion: ADC and SCC represent two different diseases with different prognosis in locally advanced esophageal carcinoma. These results might be considered when developing novel therapies and follow up strategies in this setting.