Staging guidelines for gastric cancer are largely ignored in US

Two of three Americans diagnosed with gastric cancer do not have adequate examinations for proper staging of their disease, researchers reported at the 2005 annual cancer symposium of the Society of Surgical Oncology. The majority of patients get substandard lymph node evaluations, despite clear guidelines stating at least 15 nodes must be evaluated to consider someone adequately staged. Analysis of a national cancer registry revealed that patients diagnosed with gastric cancers had a median of 10 lymph nodes examined, far short of the 15 nodes called for in the recommendations of the American Joint Committee on Cancer (AJCC).

Moreover, as many as 9 percent of patients had no nodes examined. It’s clear to anybody in the field that the curative intent therapy for gastric cancer is somewhat at a lower level of quality in the United States compared to some Asian countries. The quality is reflective of problems in operative procedures and problems in staging. A large number of patients are not appropriately staged, and many have no nodes looked at. The implications are unclear. But clearly this is suboptimal, and the potential for incomplete resection very high. It’s an interesting problem because we don’t see the United States as a place where the health quality is poor, but gastric cancer is a disease that falls through the cracks.

Poor lymph node examination may contribute to the low five-year survival rate of 23 percent in the United States. In Japan, where surgeons dissect all perigastric, common hepatic, left gastric, celiac and splenic lymph node stations, people with gastric cancer survive longer. However, surgical specialists debate whether lymph node evaluation is more effective when based on the number of lymph nodes or on their location. In the past year, one thing that has emerged is that gastric cancer survival is directly linked to the number of lymph nodes examined. Three studies show that survival rates for patients with every stage of gastric cancer improved when they had 15 or more lymph nodes examined.

Associate Professor of Surgical Oncology at the University of Minnesota Medical School at Minneapolis, conducted an analysis of the surveillance, Epidemiology, and End Results cancer registry, which collects information on cancer and survival from various regional registries representing 14 percent of the population. Between 1998 and 2001, they found 3,593 patients diagnosed with gastric cancer who underwent at least a partial gastrectomy. This is a really important study because in the United States, the standard of care for the management of gastric cancer with adjuvant chemotherapy is based on a randomized trial where the majority of patients had insufficient lymph node retrieval. Randomized trials in Europe demonstrate improved survival with adequate surgery and no chemotherapy. Do you think inadequate lymph node retrieval is a consequence of poor surgery or inadequate lymph node retrieval by the pathologist.

The problem probably stems from both surgeons and pathologists. Surgeons have to work with our pathologists to better this. Clearly, there are some institutional practices that can improve lymph node evaluations. The standard for lymph node examination was significantly affected by the hospital where patients were treated. At Memorial Sloan-Kettering Hospital in New York City, patients have an average of 24 lymph nodes examined. Lymph node evaluation varies across the country. Resident of Hawaii were two to four times more likely to have adequate examinations than were people living elsewhere. With 56 percent of the population having 15 nodes evaluated, Hawaii stood out as the only region in the country where more than half of the patients were treated according to AJCC guidelines.

Surgeons and pathologists in Hawaii are more experienced in dealing with gastric cancer because of a higher incidence there than in other areas of the country. There are many reasons why staging and overall survival outcomes are so poor in the rest of the country. He suggested that patient treated in community centers could be sicker than those treated at referral center, or that surgeons are not aware that the number of nodes removed can influence survival outcomes. Sometimes surgeons do not report every node examined on their staging form, which would have the effect of making lymph node examinations appear less adequate than they are.

They think that not enough nodes are examined overall, but many times these staging forms make it easy to miss out or omit the sections for number of nodes. The study also showed that patients were more likely to have an adequate examination if their disease was node-positive. In addition, patients who were younger than 64 years old, were female or had more radical surgeries were significantly more likely to have 15 nodes examined. The study results mirror those from a similar study showing that only 44 percent of patient who underwent colorectal cancer surgery in the United States in 2001 had 12 or more lymph nodes evaluated, as recommended by the International Union Against Cancer and the AJCC.