TUESDAY, Oct. 12 (HealthDay News) -- Many patients with incurable cancer are still being screened for common cancers, although these tests are unlikely to provide any benefit, researchers from Memorial Sloan-Kettering Cancer Center in New York City have found.

Specifically, many patients diagnosed with advanced lung, colorectal, pancreatic, gastroesophageal or breast cancer are still undergoing the ordeal of routine breast, prostate and colon cancer screening, said the researchers. Not only might these patients suffer from invasive procedures like colonoscopies near the end of life, the researchers said, but they face the unnecessary risk of additional tests, biopsies and psychological distress resulting from the detection of new malignancies.

"For patients living with advanced cancer, cancer screening should not be a routine procedure," said lead researcher Dr. Camelia S. Sima, an assistant attending biostatistician.

"Patients living with advanced malignancies and their doctors should engage in a realistic conversation about the risks and benefits associated with cancer screening in [the] face of a severely limited life expectancy," she added.

The report is published in the Oct. 13 issue of the Journal of the American Medical Association.

For the study, Sima's team collected data on 87,736 Medicare patients aged 65 years or older with advanced lung, colorectal, pancreatic, gastroesophageal or breast cancer, whose data was reported in the Surveillance, Epidemiology, and End Results (SEER) tumor registries.

These patients were followed from their diagnosis, between 1998 and 2005, until they died or to the end of 2007.

To compare the findings to a control group, the researchers also collected data on 87,307 similar Medicare patients without cancer, who were matched with the other individuals for age, race, sex and SEER data. In both patient groups, Sima's team looked at the rates of mammograms for breast cancer, Pap tests for cervical cancer, prostate-specific antigen (PSA) tests for prostate cancer and endoscopy for colon cancer.

The investigators found that among women with advanced cancer, 8.9 percent had a mammogram, compared with 22 percent of those without cancer; and 5.8 percent of the cancer patients had a Pap test, compared with 12.5 percent of those without cancer.

Among men, 15 percent of those with advanced cancer had a PSA test for prostate cancer, compared with 27.2 percent of those without cancer.

Among all patients, 1.7 percent of those with advanced cancer underwent a colonoscopy to check for colon cancer, compared with 4.7 percent of those without cancer, the researchers found.

Patients who had been screened more often were more likely to continue being screened after being diagnosed with advanced cancer, as were those who were wealthier and married, Sima's group noted.

There needs to be greater awareness that cancer screening when one is near the end of life is unlikely to provide a benefit, Sima pointed out.

"Screening guidelines could be reassessed to address the appropriateness of screening for patients whose very limited life expectancy due to advanced cancer negates any potential benefit that may be derived," Sima said.

Commenting on the study, Dr. Len Lichtenfeld, deputy chief medical officer at the American Cancer Society, said that "we can do a lot of good with screening, but we have to recognize that there comes a time when it's simply not the right thing to do."

Lichtenfeld suggested that patients should discuss the appropriateness of a screening test with their doctor. "Putting people at the end of life through screening is not appropriate for the person, and from a societal viewpoint, it's not a good use of our limited resources," he said.

"Why would this happen in the first place?" Lichtenfeld asked. "It flies in the face of compassion; it flies in the face of common sense."

In addition, he noted, should a test find a cancer, then what happens? "I hope doctors would not be doing additional procedures on people who are nearing the end of their lives," Lichtenfeld said.

More information

For more information on cancer screening, visit the U.S. National Cancer Institute.