Thirty-Year Study Shows Improved Survival Rates for Esophageal Cancer

A 30-year study conducted by The University of Texas M.D. Anderson Cancer Center has revealed that survival rates for patients who undergo surgery for esophageal cancer have improved dramatically as new treatment, staging and surgical techniques have evolved.

Dr. Stephen G. Swisher, director of the Esophageal Cancer Program in the department of thoracic and cardiovascular surgery at M.D. Anderson, reported to the American Surgical Association April 27 that 46 percent of patients at the end of the study period survived at least three years after surgery for cancer of the esophagus, compared to 27 percent of patients at the beginning of the study.

In his presentation, Dr. Swisher reported that median survival doubled from 17 months to 34 months. All 1,097 patients in the study were treated at M.D. Anderson from 1970 to 2001.

"The three-year survival rates are especially important because the patients who reach this milestone are those who most likely will live disease free," said Dr. Swisher, who is also associate professor of thoracic surgery at M.D. Anderson. "The study shows that while the key to improving patients’ survival of esophageal cancer is complete resection or removal of the tumor, many factors have evolved allowing surgeons a better opportunity for complete resection."

There were 76 percent complete resections when the study began and 95 percent when it ended.

Dr. Swisher said the following factors played an important role in improving the chance for complete removal of the tumor and shifting survival rates:

Increased use of preoperative chemoradiation

The increasing use of combination chemotherapy and radiation therapy appears to play a major role in complete resection of the tumor at the time of surgery. Rigorous for a patient, the combination therapy shrinks the tumor so the surgeon has a less-cancerous mass to remove and greater opportunity for clean, disease-free parameters.

Dr. Swisher said preoperative chemotherapy and radiation therapies given separately are ineffective in shrinking esophageal tumors. However, when both therapies are given together prior to surgery, there appears to be a great impact on shrinkage. A randomized trial in this area is needed to confirm the concept.

Better pretreatment staging of tumors

With the advent of more specific pretreatment staging in the last 30 years, there is a greater opportunity to predict which patients will most benefit from preoperative chemoradiation and have a greater chance for complete removal of the tumor.

Between 1970 and 1985, patients were staged only with a barium swallow and chest X-ray, while from 1986 to 1996, patients were staged with those two tests plus computed tomography scan and endoscopy. From 1997 to 2001, patient evaluation consisted of high-resolution CT scanning and esophageal ultrasound with fine-needle aspiration in some cases of suspicious lymph nodes. In the last several years, PET scanning has been added to patient assessments.

Improved surgical techniques

In the 1970s, surgical resections of esophageal tumors were often done in two separate operations. Today, the surgery is combined into a single procedure, reducing a patient’s stay in the hospital and decreasing their risk of complications. In the study, combined hospital and 30-day mortality declined from 11 percent to 6 percent, though the technique does not appear to have an impact on long-term survival.

In a related finding, the study also confirmed previous research that adenocarcinoma has replaced squamous cell carcinoma as the predominant type of esophageal tumor in the Western world.

Dr. Swisher said early 1980s risk factors such as smoking and drinking decreased while gastroesophageal reflux, or heartburn, increased. Adenocarcinoma is closely associated with increased heartburn resulting from a high-fat diet, and squamous cell esophageal tumors are aligned with alcohol intake.

American Cancer Society statistics show that more than 12,000 new cases of esophageal cancer are diagnosed each year.

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©2006 Texas Medical Center

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