Patterns of regional recurrence after curative D2 resection for stage III (N3) gastric cancer: Implications for postoperative radiotherapy

Background and purposeTo analyze patterns of regional recurrence after curative gastrectomy and D2 lymph node dissection in patients with stage III (N3) gastric cancer.Materials and methodsBetween 2004 and 2008, 2918 patients with primary gastric cancer underwent D2 resection at a single institution. A retrospective review was performed on 382 patients in stage III with N3 disease. Of these, 357 patients (93.5%) received adjuvant chemotherapy. None of the patients received pre- or postoperative radiotherapy.ResultsMedian follow-up was 56.3 months. The 5-year regional failure free-survival (RFFS) rate was 63.6%. Regional failure (RF) as any component of first recurrence occurred in 91 patients (23.8%), with isolated regional failure occurring in 49 (12.8%). The most commonly involved lymph nodes were the No. 16b, No. 16a, No. 12, No. 14, No. 13, and No. 9 nodes. RFFS was adversely affected by advanced nodal stage (N3b vs. N3a). The 5-year progression-free survival rate was 32.1% and overall survival was 41.5%.ConclusionThe most prevalent nodal recurrence in patients with advanced gastric cancer was in the nodal basin outside the D2 dissection field. Our findings may help physicians construct a lymph node target volume for radiation treatment of gastric cancer after D2 dissection.