Patterns and predictors of locoregional recurrence following neoadjuvant chemoradiation for esophageal cancer.

173 Background: Despite neoadjuvant chemoradiation (nCRT) followed by esophagectomy for locally advanced esophageal cancer, locoregional recurrences (LRR) are common. Specific risk factors for LRR have yet to be identified. Methods: Patients with esophageal cancer who were treated with nCRT and esophagectomy were identified from a single institution, prospectively maintained database(1996-2013). Timing and locations of recurrences were described and predicting factors of LRR were analyzed. Results: Out of 456 patients treated with nCRT for esophageal cancer, 167 patients developed known recurrence. Locoregional and distant recurrences were observed in 69(15.1%) and 140(30.9%) patients, respectively. Median recurrence-free survival was 38.5 months with a median follow-up of 30.4 months. Sixty-eight patients(40.7%) developed recurrence at multiple sites. The median time to recurrence was 13.5 months and survival following recurrence was only 8.0 months in the 27 patients(16.2%) with solitary LRR. Overall survival in patients with solitary LLR was 23.6 months, compared to 20.8 months in all patients who developed distant recurrence. Univariate analysis identified lymph node ratio > 0.5(OR 2.42, p = 0.030), non-complete pathologic response(OR 1.90, p = 0.022), positive margins(OR 3.58, p = 0.028) and lymphovascular invasion(OR 2.82, p = 0.001) as significant predicting factors for LRR. While perineural invasion(p = 0.055), nodal stage(0.053) and use of adjuvant therapy(p = 0.060) approached significance, other factors such as tumor stage, type of surgery (Ivor-Lewis vs transhiatal), radiation dose and use of IMRT were not significant predictors of LRR. Only lymphovascular invasion was an independent predictor of LRR. Conclusions: Prognosis following LRR in patients with esophageal cancer treated with nCRT is poor but is better than in patients who develop distant recurrence. High lymph node ratio, positive margin status, non-complete pathologic response and the presence of lymphovascular invasion are predictive of LRR following nCRT for esophageal cancer.