Nonspecific tumor markers in the era of value based medicine: Role of CA 19-9 in the pelvic mass workup

Background: When encountering a pelvic mass, CA 125 and CEA are usually obtained to evaluate for ovarian or colon cancer. The clinical importance of ordering a CA 19-9 level is unknown. Does it offer valuable information or merely add confusion and additional workup if elevated? Methods: 3,370 women were retrospectively identified via CPT codes for pelvic mass and CA 19-9. Initial analysis reviewed the subspecialty of the primary investigator using CA 19-9 in their initial workup, and its correlation to a gynecologic pathology. In the cases where an OBGYN was the primary investigator additional tumor markers, age, race, menopausal status, imaging, surgical interventions and final pathology were further analyzed. Results: Out of 3,370 women 982 had an abnormal CA 19-9. The distribution of subspecialties that utilized CA 19-9 in their initial work up was Hematology Oncology 31.6%, Internal Medicine 18.7%, Gastrointestinal 18.2%, Gynecology 9.2%, Surgery 8.8%, Emergency Medicine 5.7%, Transplant 4.9%, and Family Medicine 2.9%. Of the patients evaluated by Gynecology, 32.2 % were found to have elevated CA19-9 which led to additional work-up of the upper GI tract in 18.9% including MRI, and PET preoperatively. Further analysis revealed that there was no correlation between the elevation of CA 19-9 and whether the tumor was malignant or benign [p value = 0.45] even after being adjusted for: menopausal status, presence of endometriosis, or pathology including mucinous cell type. Conclusions: The majority of adnexal masses are benign; the main goal of diagnostic evaluation is to exclude malignancy. Value based medicine is implemented to help improve health care quality, and efficient utilization of health care resources. Based on this retrospective analysis the use of CA 19-9 in evaluation of a pelvic mass does not offer information that directly improves patient outcome, but rather correlates to the increased misuse of health care resources