Should adenosquamous esophageal cancer be treated like adenocarcinoma or squamous cell carcinoma?. Issue 3 (27th May 2020) - Gamboa, Adriana C.
Abstract: Background: Esophageal adenocarcinoma (AC) and squamous cell carcinoma (SCC) have distinct outcomes, treatment strategies, and response profiles to therapy. Adenosquamous carcinoma (ASC) is thought to behave more aggressively than each of its counterparts. The aim of this study is to determine ifASC is best managed as AC or SCC. Methods: National Cancer Database (2004‐2015) was queried for patients with nonmetastatic esophageal ASC. The analysis was stratified by clinical node‐negative (cN0) or clinical node‐positive (cN1‐3). Treatment was categorized into chemoradiation alone, surgery alone, or preoperative chemoradiation followed by surgery. The primary outcome was 5‐year overall survival (OS). Results: Among 352 patients, 43% were cN0 (n = 151), 57% were cN1‐3 (n = 201) and 55% had chemoradiation alone (n = 194), 15% surgery alone (n = 53), and 30% preoperative chemoradiation (n = 105). Among patients who had preoperative chemoradiation, 20% had pathologic complete response (n = 17). For either cN0 or cN1‐3, Charlson‐Deyo Comorbidity Index did not differ among the treatment groups(all p > 0.05). On Kaplan‐Meier analysis for cN0, treatment with surgery alone had comparable OS to preoperative chemoradiation (47% vs 34%; P = .5) and each had improved OS compared to chemoradiation alone (30%; P = .02; P = .06). On univariate analysis for cN0, clinical T category was not associated with OS. For cN1‐3, however, preoperative chemoradiation was associated with improved OS when compared to chemoradiation alone or surgery alone (27% vs 19% vs 0%; P < .001). This persisted when accounting for age and clinical T category (hazard ratio: 0.45; P < .001). Conclusion: Esophageal ASC behaves more like AC in response to chemoradiation and survival based on treatment modality. A complete response to chemoradiation is only 20% unlike what has been shown for SCC, where chemoradiation is an acceptable definitive therapy. Esophageal ASC should be managed more like AC.