Nandie Wu

Regional but fatal: Intraperitoneal metastasis in gastric cancer

Peritoneal carcinomatosis appears to be the most common pattern of metastasis or recurrence and is associated with poor prognosis in gastric cancer patients. Many efforts have been made to improve the survival in patients with peritoneal metastasis. Hyperthermic intraperitoneal chemotherapy remains a widely accepted strategy in the treatment of peritoneal dissemination. Several phase II-III studies confirmed that the combined cytoreducitve surgery and hyperthermic intraperitoneal chemotherapy resulted in longer survival in patients with peritoneal carcinomatosis. In addition, proper selection and effective regional treatment in patients with high risk of peritoneal recurrence after resection will further improve prognosis in local advanced gastric cancer patients.

Peritoneal metastasis in relation to outcome and therapeutic strategy in gastric cancer

Background: The prognosis of locally advanced and metastatic gastric cancer remains dismal. The aim of this study was to investigate the patterns of recurrence or metastasis of advanced gastric cancer and determine the factors associated with survival, which may help in identifying effective treatment strategies. Methods: A retrospective analysis of 349 patients with stage III/IV gastric cancer was performed. The relationships between metastasis patterns and clinicopathological characteristics and overall survival were evaluated. Results: Peritoneal metastasis was detected as any part of the metastasis/recurrence pattern in 219 patients (62.8%), while distant sites were involved in 208 patients (59.6%). 81.1% of the patients developed metastasis in peritoneal cavity (peritoneal or liver) at the time of recurrence or diagnosis. Stage III patients with locoregional recurrence (LR) had longer overall survival time than those with peritoneal or distant recurrence (DR) (21 vs . 15 months, HR: 0.628; P=0.047), while stage IV patients with peritoneal metastasis had shorter survival (7.5 vs . 14 months) and a higher risk of death (HR: 2.026; P=0.004). Conclusions: Peritoneal metastasis appears to be the most common pattern and is associated with poor prognosis in gastric cancer patients. Effective regional treatment is important to guide appropriate further therapy in advanced gastric cancer patients.

Personalized Intraperitoneal Strategies in Gastric Cancer

Gastric cancer is the fourth most common cancer and the second leading cause of cancer deaths worldwide [1]. Except countries such as Korea and Japan that have routine national screening programs, most patients with gastric cancer are in advanced stages of the disease as early-stage gastric cancers are usually without symptoms and often develop advanced stage even after radical surgery. Despite developments in the surgical treatment of gastric cancer, there is a relatively high recurrence rate. Specifically, the 5-year overall survival rate for all diagnosed patients averages 24.5% in Europe [2] and 40–60% in Asia [3, 4]. The main reason for post-surgery treatment failure for gastric cancer is peritoneal dissemination, which is caused by the seeding of free cancer cells from the primary gastric cancer. This is one of the most common types of metastasis for gastric cancer. Gastric cancer patients with macroscopic peritoneal metastasis have very poor prognoses, with a median overall survival of 3–6 months [5, 6]. In this chapter, we try to describe the influence of peritoneal metastasis on survival in patients with gastric cancer, the possible mechanism of peritoneal metastasis, and individualized treatment strategy of gastric cancer patients at high risk for developing peritoneal metastasis.