Highlights From the 2006 Gastrointestinal Cancers Symposium

Several new developments in the treatment of gastrointestinal cancers were announced at the 2006 Gastrointestinal Cancers Symposium in San Francisco, California. Held January 26 - 28, 2006, this scientific meeting was cosponsored by the American Gastroenterological Association (AGA), the American Society of Clinical Oncology (ASCO), the American Society for Therapeutic Radiology and Oncology (ASTRO), and the Society of Surgical Oncology (SSO). The meeting included more than 400 abstracts, attracting more than 2,000 physicians.

Gastrointestinal cancers include cancers of the colon, rectum, stomach, pancreas, esophagus, anus, gallbladder, liver, and bile duct. According to the American Cancer Society, more than 250,000 people are diagnosed with gastrointestinal cancers each year in the United States, and an estimated 136,000 people die of these diseases. Gastrointestinal cancers account for about 19% of all new cancer diagnoses and nearly 24% of all cancer deaths.

Esophageal cancer

Esophageal cancer is cancer of the esophagus, the hollow, muscular tube that connects the throat to the stomach. Esophageal cancer is becoming more common in the United States and can be difficult to treat. The most common treatment for esophageal cancer is surgery.

Results of a new study show that patients with early stage esophageal cancer who were treated with chemotherapy, radiation therapy, and surgery lived more than twice as long as patients who were treated with only surgery. After five years, 39% of the patients who received the combination therapy were still alive, compared with 16% of the patients who received only surgery.

What this means for patients

Although the number of patients in this study was smaller than planned, the results suggest that treating patients with surgery, radiation therapy, and chemotherapy is better than treating patients with surgery alone.

Gastrointestinal stromal tumor (GIST)

Gastrointestinal stromal tumor (GIST) is a rare cancer of the connective tissue in the gastrointestinal tract. Approximately 3,000 to 6,000 cases are diagnosed each year in the United States. About 60% to 70% of GISTs occur in the stomach, and 30% to 40% occur in the small intestine.

Imatinib (Gleevec) is the standard treatment for GIST. Although imatinib is highly effective in the initial treatment of GIST, the drug stops working in more than half of patients after about two years. Similar to imatinib, sunitinib (Sutent) is a pill that can be taken by mouth and belongs to a class of drugs called targeted therapies, which means that it works by blocking specific proteins that help cancer cells grow and spread.

The results of a phase III clinical trial showed the time it took for a tumor to grow was more than four times longer for patients who received sunitinib (27.3 weeks), compared with patients who did not receive sunitinib (6.4 weeks). In addition, sunitinib lowered the risk of death by more than 50%. The side effects of sunitinib were mild and included fatigue (tiredness), diarrhea, nausea, mouth sores, and skin discoloration.

What this means for patients

This study shows for the first time that another targeted therapy, sunitinib, can slow the growth of cancer and extend survival for patients with GIST when imatinib stops working. Sunitinib has recently been approved by the U.S. Food and Drug Administration (FDA) for use in this case.

Liver cancer

Liver cancer is diagnosed in nearly 18,000 people each year in the United States. The most common type of liver cancer is called hepatocellular carcinoma (HCC). Liver transplantation is a treatment option when the cancer has not spread beyond the liver and an appropriate donor can be found.

In the first large analysis in the United States of transplantation for early stage liver cancer, researchers found that three-quarters of patients with HCC that had not spread and who received a liver transplant were alive five years later, compared with less than 20% of patients who did not undergo transplantation.

The data analysis also showed that African Americans and Asians were less likely to receive a transplant than white patients. The reasons for these differences weren't studied, but the researchers speculated that transplantation rates may be affected by factors such as living too far from transplantation centers, having other health-related problems, or receiving referrals too late in the course of disease.

What this means for patients

The results of this study suggest that liver transplantation is a good treatment option for early stage liver cancer for patients who meet transplantation criteria. Patients with this disease may consider asking their doctors for a referral to a medical center that offers liver transplantation. Further research is needed to determine the cause of the differences in transplantation rates to ensure that all eligible patients are considered for transplantation.

Pancreatic cancer

Pancreatic cancer is the fourth leading cause of cancer death in men and the fifth leading cause of cancer death in women in the United States. Although pancreatic cancer rates have declined slowly in men and women over the past 25 years, it remains the tenth most common cancer in both men and women. Pancreatic cancer can be difficult to treat because it has usually spread outside of the pancreas by the time of diagnosis.

The most common chemotherapy drug used for the treatment of pancreatic cancer is gemcitabine (Gemzar). Gemcitabine has been shown to modestly improve survival for patients with advanced pancreatic cancer. A recent analysis of two randomized trials showed for the first time that adding a platinum-containing drug to standard chemotherapy slows the growth of pancreatic cancer and helps patients live longer. Overall survival among patients in the combination chemotherapy group was nine months, compared with just over seven months in the gemcitabine group. Platinum drugs include cisplatin (Platinol) and oxaliplatin (Eloxatin).

What this means for patients

In patients who do well on chemotherapy, adding a platinum drug to gemcitabine can improve survival and slow the growth of cancer.

Colorectal cancer

Colorectal cancer is cancer that begins in the colon or rectum, which is part of the large intestine. Colorectal cancer accounts for 57% of all gastrointestinal cancers. Advanced colorectal cancer has spread outside of the colon and rectum, and the standard treatment is combination chemotherapy.

In a phase III clinical trial from Italy, researchers compared the combination of drugs known as FOLFIRI (fluorouracil [5-FU], leucovorin [Wellcovorin], and irinotecan [Camptosar]) with FOLFOXIRI (5-FU, leucovorin, irinotecan, and oxaliplatin). Not only did patients in the group receiving FOLFOXIRI live longer (22.6 months) than those in the group receiving FOLFIRI (16.7 months), but the tumors in the patients in the group receiving FOLFOXIRI did not grow or spread for 9.8 months, compared with 6.8 months for the patients receiving FOLFIRI. In addition, the tumors in 66% of patients who received FOLFOXIRI disappeared or became smaller, compared with 41% of patients in the group receiving FOLFIRI.

Side effects were more common in patients receiving FOLFOXIRI and included diarrhea, vomiting, neuropathy (nerve damage), and low white blood cell counts.

A second phase III clinical trial showed that a drug called xaliproden (Xaprila) lowered the occurrence of peripheral sensory neuropathy in patients with metastatic colorectal cancer on the FOLFOX (5-FU, leucovorin, and oxaliplatin) regimen. Peripheral sensory neuropathy is a side effect caused by oxaliplatin that causes numbness, tingling, and burning in the arms, hands, legs, and feet of patients. More than 90% of patients receiving oxaliplatin as part of the FOLFOX therapy for metastatic colorectal cancer have reported experiencing these symptoms at some point during their treatment. Xaliproden, a pill that can be taken by mouth, reduced and did not alter the effectiveness of the FOLFOX therapy.

What this means for patients

The first study on FOLFOXIRI supports previous studies showing that oxaliplatin is effective for the treatment of advanced colorectal cancer. Results of the second study on xaliproden show that peripheral sensory neuropathy from oxaliplatin can be reduced, which improves the quality of life of people taking oxaliplatin. A larger clinical trial testing xaliproden to confirm these initial findings is being planned.

More Information

2006 Gastrointestinal Cancers Symposium Virtual Meeting

Cancer.Net Guide to Esophageal Cancer

Cancer.Net Guide to Gastrointestinal Stromal Tumor

Cancer.Net Guide to Liver Cancer

Cancer.Net Guide to Pancreatic Cancer

Cancer.Net Guide to Colorectal Cancer

Chat Transcript: Gastrointestinal Cancers: Scientific News for Patients

Last Updated: January 30, 2006