Quality of post-treatment surveillance of early stage breast cancer in Texas.

BACKGROUND: Only annual mammography and physical examination are recommended for the post-treatment surveillance of early stage breast cancer.
METHODS: We used Texas Cancer Registry-Medicare linked data (2001-2007) to identify physician visits and use of mammography, magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET) CT in patients ≥ 66 years old with ductal carcinoma in situ and stage I-III ductal carcinoma who underwent curative-intent operations. We also evaluated the trends in use of recommended and nonrecommended tests.
RESULTS: We identified 8,598 patients with resected ductal carcinoma in situ (37.3%) or invasive ductal cancer (62.7%). Breast-conserving therapy was performed in 59%. Only 55% saw a physician twice a year for 2 years and underwent annual mammography for 2 consecutive years in the surveillance period. Mammography use decreased from 81% in 2001 to 75% in 2007 (P < .0001), and breast MRI use rose from 0.5% to 7.0% (P < .0001). For asymptomatic patients, the use of CT/MRI of the abdomen, chest, and head was 27%, 23%, and 22%, and this slightly increased during the study period. There was a significant increase in PET/PET CT use, from 2% in 2001 to 9% in 2007 (P < .0001). There was a concomitant decrease in bone scan use from 21% in 2001 to 13% in 2007 (P < .0001).
CONCLUSION: Adherence to evidence-based guidelines has been substandard and the use of nonrecommended tests has persisted over the study period. The rise in PET use and attendant decrease in bone scan implicates a population receiving PET scan in lieu of bone scan for surveillance of asymptomatic metastatic disease. In an elderly population of breast cancer patients in Texas, these findings imply both underuse and overuse.