The purpose of this case report is to describe the failure of standard diagnostic work up in the presence of an advanced stage endometrial cancer and briefly review the literature about the efficacy of the currently utilized diagnostic tools in the evaluation of women with postmenopausal bleeding (PMB). A 71-year-old normal weight lady presented with an unprovoked PMB. Initial evaluation consisted of pelvic ultrasound followed by office hysteroscopy and directed endometrial biopsy. Biopsy was negative but her symptom persisted, so she had a repeat hysteroscopy with dilatation and curettage (D&C) in the operating room. The D&C histology was again negative but elevated CA 125 and a suspicious looking intramural “fibroid” on ultrasound and MRI prompted our advice for hysterectomy. At the time of surgery, a stage III C endometrial cancer was found. A high level of vigilance is required in the evaluation of women presenting with symptoms suspicious for endometrial cancer. When these symptoms persist despite negative initial work up, continuing evaluation and sometimes intervention are required on the part of the clinician.