Esophagogastric Junction and Gastric Adenocarcinoma: Neoadjuvant and Adjuvant Therapy, and Future Directions

In North America, gastric cancer is the third most common gastrointestinal malignancy and the third most lethal neoplasm overall. In Asia, gastric cancer represents an even more serious problem: in Japan, it is the most common cancer in men. The standard primary therapy for gastric cancer is surgical resection; in esophagogastric-junction (EGJ) adenocarcinoma, which is often included in studies of gastric cancer, surgery is also typically the initial management strategy. However, the rates of locoregional and distant recurrence following surgery with curative intent have remained high. Investigators have explored a variety of ways of reducing these rates and improving survival in patients with gastric and EGJ cancers. These strategies have included explorations of the optimal extent of regional lymphadenectomy at the time of gastric resection; investigation of different neoadjuvant, perioperative, and adjuvant chemotherapy regimens; use of preoperative and postoperative radiation therapy; and the use of pre- and postoperative chemoradiotherapy (CRT).To date, benefit has been seen in gastric cancer patients with the use of what is called a"D2 resection"(which includes lymph nodes of stations 7 through 12) and with adjuvant CRT (in the West) or adjuvant chemotherapy with S-1 (in Japan); and neoadjuvant CRT has been shown to have a survival benefit in patients with EGJ cancers.