Randomized clinical trial of adjuvant chemotherapy with intraperitoneal and intravenous cisplatin followed by oral fluorouracil (UFT) in serosa-positive gastric cancer versus curative resection alone: final results of the Japan Clinical Oncology Group trial JCOG9206-2

Long-term survival after gastrectomy for cancer in randomized, controlled oncological trials: comparison between West and East

BACKGROUND

The presence of mixed evidence about the value of lymphadenectomy in gastric cancer surgery coupled with the difference in patients' demographics and tumor stage between the West and East have doubted the needs to standardize surgical techniques in Western clinical practice. The purpose of this study was to compare survival rates between the West and East following gastrectomy in randomized, controlled, oncological trials with appropriate adjustment for confounding variables.

METHODS

Systematic search revealed 25 trials that have randomization into surgery and chemotherapy versus surgery alone between 1995 and 2012 (n = 7 (East) and n = 18 (West)). End points were 5-year survival and cancer recurrence.

RESULTS

There was association between gastrectomy performed in the East and improved 5-year survival (pooled odds ratio (OR) 4.83; 95 % confidence interval (CI) 3.27-7.12) and reduced cancer recurrence (pooled OR 0.33; 95 % CI 0.2-0.54). Association of improved 5-year survival with surgery in the East remained when meta-regression adjusted for the effect of age, sex, chemotherapy, tumor depth and nodal status, and gastrectomy type. Association of reduced cancer recurrence also persisted with meta-regression adjusting for age, chemotherapy, nodal status, and gastrectomy type. However, when adjustment for the percentage of patients with tumor depth T1 or 2 was made statistical significance was lost.

CONCLUSIONS

This analysis shows association between gastrectomy performed in Eastern countries and improved survival. The known difference in surgical techniques between the East and the West is one potential unexamined variable that may be responsible in part for such discrepancy in outcomes.

Lymph node dissection for gastric cancer: a critical review

Gastric cancer is one of the most common neoplasms and an important cause of cancer-related death worldwide. Efforts to reduce its high mortality rates are currently focused on multidisciplinary management. However, surgery remains a cornerstone in the management of patients with resectable disease. There is still some controversy as to the extent of lymph node dissection for potentially curable stomach cancer. Surgeons in eastern countries favor more extensive lymph node dissection, whereas those in the West favor less extensive dissection. Thus, extent of lymph node dissection remains one of the most hotly discussed aspects of gastric surgery, particularly because most stomach cancers are now often comprehensively treated by adding some perioperative chemotherapy or chemo-radiation. We provide a critical review of lymph nodes dissection for gastric cancer with a particular focus on its benefits in a multimodal approach.

Gastric cancer eastern experience

Several guidelines are used for cancer therapy throughout the world. The Japan Gastric Cancer Association guideline, whereby standard surgery for T2 to T4 curable gastric cancer is defined as more than two-thirds gastrectomy with D2 dissection, are widely followed, with further data being gathered from either single institutions or nationwide registry. In the East, D2 dissection shows much better results than less extended surgery followed by adjuvant treatment. Adjuvant chemotherapy without radiotherapy shows significantly better survival results than surgery alone only when D2 dissection is applied. Without good local control, including regional lymph node metastasis, the cure rate cannot be high.