Objective: The purpose of this study was to determine the benefit of routine pelvic CT in the evaluation of patients with primary breast cancer and to assess the frequency with which equivocal or abnormal findings on pelvic CT prompted the performance of additional studies or procedures that yielded results relevant to patient care.
Materials and methods: The reports of 6628 body CT scans that included images of at least the pelvis in 2426 patients with breast cancer during a 9-year period were reviewed. The presence and sites of reported definite or probable metastases or pelvic tumors were recorded for each scan. Also, the types and results of diagnostic examinations and procedures prompted by equivocal or abnormal findings on pelvic CT were recorded.
Results: Pelvic metastases shown on CT were the only known site of metastasis in 13 (0.5%) of 2426 patients, and four other patients (0.2%) had new or enlarging pelvic metastases despite the presence of stable extrapelvic metastases. The pelvic metastases in these 17 patients were located in bone only in 11 patients, in adnexa only in five patients, and in adnexa, endometrium, and bone in one patient. In addition, pelvic CT led to the performance of 204 additional radiologic examinations, including 186 pelvic sonographic examinations, and 50 surgical procedures; 215 (84.6%) of these 254 additional examinations and procedures yielded normal, benign, or indeterminate results.
Conclusion: The routine use of pelvic CT in the evaluation of patients with breast cancer has an extremely low yield and often prompts performance of pelvic sonographic or surgical procedures, the results of which were rarely relevant to cancer therapy.