Results and controversial issues regarding a para-aortic lymph node dissection for advanced gastric cancer

More than 20% of the patients with advanced gastric cancer display para-aortic lymph node (PAL) metastasis. Numerous retrospective comparative studies have reported an improved prognosis using an extensive lymph node dissection (D2) with PAL dissection, compared with D2 alone. However, many issues associated with a PAL dissection remain, such as the importance of stage migration, learning curves, and micrometastasis. This review focuses on the results and controversial issues associated with a PAL dissection. The depth of tumor invasion correlates with PAL metastasis, and whether PAL should be dissected in patients with T2 tumors remains controversial. The rate of PAL positivity is higher for cancers involving tumors of the upper third of the stomach. The most important lymphatic terminals for the stomach seem to comprise the a2 lateroaortic and b1 interaorticocaval PAL areas in tumors of the upper third and lower third, respectively. While the 5-year survival rate is about 10% after D2 plus a PAL dissection, patients with a potentially curative operation live longer. Early major complications after a PAL dissection occur in 25% of all cases, predominantly due to a pancreatectomy. A randomized clinical study evaluating a PAL dissection was launched in 1995 in Japan. Furthermore, numerous reports of patients with gastric cancer and PAL metastases responding to chemotherapy should also be considered.