COLUMBUS, Ohio--Many of the diagnostic tests and procedures following treatment for breast cancer fail to extend survival, as demonstrated by two randomized, prospective studies and nine retrospective studies, said Victor G. Vogel, MD, MHS, director of the Comprehensive Breast Cancer Program at the University of Pittsburgh.
Add to this the drawbacks of these follow-up tests, including cost, and it becomes very difficult to justify their continued use, Dr. Vogel said at the Ohio State University James Cancer Hospital and Research Institute Third Annual Oncology Update.
The routine use of blood chemistry studies and tumor markers CEA and CA 15-3 cannot be recommended based on a review of the literature, he stressed. In addition, insufficient data exist to support follow-up surveillance with chest x-ray, bone scan, hepatic ultrasound, abdominal or chest CT scan, and the tumor marker CA 27-29.
"We can no longer keep doing something just because we want to," he said. "We cannot justify use of these tests in the face of the data." He emphasized that he was referring to follow-up testing, not testing during active treatment.
Despite intensive follow-up, 70% of cancer recurrences are identified from symptoms by the patient herself, Dr. Vogel noted. In addition, the best predictor of survival continues to be the size of the original tumor and the extent of axillary node involvement.
A False Assumption
The existing belief among many physicians and patients is that the value of follow-up monitoring is in the early detection of recurrent disease, he said. The assumption is that since early detection of initial cancer lengthens survival quite significantly, then early detection of recurrent cancer must be beneficial, too.
However, studies show that early detection and early treatment of recurrent cancer are not associated with improved survival. Rather, early warning of cancer recurrence, such as provided by the serologic tumor markers CA 15-3 and CA 27-29, lengthens the period of recurrence without offering a survival advantage.
"We have to ask ourselves whether we're doing more harm removing years of life without recurrence," Dr. Vogel said, adding that looking for disease recurrence in asymptomatic individuals may even be a "disservice."
Follow-up tests suffer from other drawbacks, Dr. Vogel noted. Blood chemistry studies, chest x-rays, and CEA miss large numbers of recurrences. Bone scans have a false-positive rate greater than 20%, and CA 15-3 has a false-positive rate of about 6%. Hepatic ultrasound fails to offer a survival benefit.
CT scanning is very expensive and is unlikely to confer a benefit greater than its cost, Dr. Vogel noted. Under managed care, there will be increased pressure to justify, with scientific evidence, the ordering of expensive tests.
The desire to provide intensive follow-up monitoring, despite the lack of scientific evidence, is understandable, Dr. Vogel said. Despite all of the efforts of cancer specialists, 40% to 50% of patients diagnosed with breast cancer will eventually relapse and die. This creates anxiety and the pressure to do something, he said.
A certain amount of follow-up monitoring is recommended, Dr. Vogel said. Patients should be educated to monitor their symptoms, especially bone pain and tenderness, and pulmonary, neurological, and gastrointestinal symptoms. Breast self-examination should be done monthly.
Three-view mammography performed annually is recommended. However, no prospective, randomized trial has been done to support this advice, Dr. Vogel noted. If such a trial were done, it is possible that mammography might be recommended more frequently or that two-view mammography might be found adequate, he said.
Regular physician exams also remain an important part of follow-up monitoring of the breast cancer patient, Dr. Vogel said. Based on the scientific evidence, women should be seen every 3 to 6 months for the first 3 years, then every 6 months for the next 2 years. The majority of these visits will be to reassure the patient, he said.
A pelvic exam and Pap smear should be done once a year. Women with a history of breast cancer are known to have an increased risk of ovarian cancer. At this time, routine annual endometrial sampling of women taking tamoxifen(Drug information on tamoxifen) (Nolvadex) is not recommended, Dr. Vogel said.
Five years after active treatment, the woman can be seen annually by her primary care physician, Dr. Vogel said. Follow-up by a specialist is unnecessary. "No special expertise is required to identify metastatic disease when it recurs," he said.
However, Dr. Vogel noted, patients unprepared for this follow-up regimen are very likely to resist what they perceive as relaxed vigilance. They may oppose any change in physician or frequency of exams. One way to make such transitions smoother is to explain the schedule of follow-up monitoring very early in the patient's treatment, Dr. Vogel said.