Cancer of the uterus
Endometrial cancer is the most frequent cancer in the female pelvis in developed countries. There is no existing routine screening for endometrial cancer. The diagnosis is suspected in women presenting with post-menopausal bleeding and an endometrial thickness larger than 5 mm, measured by transvaginal ultrasound. Endometrial biopsy with endocervical curettage confirms the diagnosis in differentiating between benign and malignant conditions. Histopathology also assesses presence of tumor in the cervix, the type of cancer (adenocarcinoma, clear cell carcinoma, papillary carcinoma) and the degree of cellular differentiation (grade). Histological risk factors of poor prognosis (intermediate or high grade tumors, papillary or clear cell carcinoma) or clinical suspicion of endocervical extension warrant pre-operative staging in order to provide more prognostic information concerning the extent of the disease into the myometrium, the cervix, the adnexa, the peritoneum or lymph nodes. Deep myometrial invasion is highly correlated with lymph node invasion and cervical invasion. Preoperative knowledge of myometrial invasion can therefore influence the type and extent of initial surgical treatment (extent of lymphadenectomy and type of hysterectomy) and might increase the patient's survival due to adequate treatment at the time of diagnosis. Staging methods of endometrial cancer are abdominal and transvaginal ultrasound, contrast-enhanced CT and MR imaging. MR imaging has shown to be the most accurate method to diagnose deep myometrial invasion compared to CT and ultrasound. A MR examination changes the probability of deep myometrial invasion from 13% (grade 1), 35% (grade 2) and 54 % (grade 3) to 60%, 84% and 92% respectively with a positive result and to 1%, 5% and 10% respectively with a negative result for deep myometrial invasion. Therefore MR imaging has become the method of choice to differentiate between patients that will need lymphadenectomy (standby of a surgical oncologist, frozen section) versus those that will not and that can be operated by a general gynecologist. MR imaging is also the only imaging modality with evidence based results for cervical involvement. If myometrial, cervical and lymph node status assessment are required, contrast-enhanced MR imaging provides the most complete evaluation.