Role of Positron Emission Tomography/Computed Tomography in Preoperative Assessment of Carcinoma Endometrium—a Retrospective Analysis

Abstract

PET/CT has made significant inroads into routine oncological practice in recent times. In our study, we aim to determine its value in preoperative assessment of endometrial carcinoma. A retrospective study between January 2011 and March 2016 was conducted; we included all cases of carcinoma endometrium with a preoperative PET/CT scan. PET/CT images were analyzed and correlated with histological findings after surgical staging. A total of 46 cases were analyzed, mean age was 59.8 years, BMI 30.8 kg/m 2 , and most common histology endometrioid type (69.5%). We correlated PET/CT findings with histopathology as reference standard. PET/CT had a sensitivity of 40%, moderate specificity (75%) and accuracy (71.7%), good NPV (91.2%), but poor PPV (16.7%) for lymph node involvement. A total of 10 (21.7%) cases were detected to have distant metabolically active lesions on PET/CT, seven out of these were positive for malignancy. And 90% of them were either non-endometrioid type or grade two and higher. We found that SUV of primary tumor was significantly higher in patients with deep myometrial invasion (p = 0.018), and high-risk histological type of tumor (p = 0.022), though not statistically significant when lymph nodal involvement (p = 0.9), cervical involvement (p = 0.56), or histological grade (p = 0.84) were considered. Sensitivity and specificity of PET/CT in staging endometrial cancer is not high enough to reliably tailor lymphadenectomy. Although SUV of the primary tumor was significantly higher in patients with deep myometrial invasion and high-risk histological type, it's usefulness in classifying patients into predefined risk groups seems to be limited. However, it is useful in detecting distant metastasis especially in high-grade and non-endometrioid type of tumors. Thus, implementation of PET/CT as a surrogate for surgical staging of endometrial cancer remains enigmatic and is open to further research.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

“…Its moderate sensitivity for detecting lymph node metastases during preo-perative staging probably reflects the need for a sufficient number of neoplastic cells to induce 18 F-fluoro-2-deoxy-D-glucose hypermetabolism. [89][90][91][92][93][94][95][96][97][98][99][100] The usefulness of maximal standardized uptake value in classifying patients into predefined risk groups is limited. 101 A pre-operative CT scan has a clinical utility in patients with endometrial carcinoma in detecting metastatic disease.…”

A Radiomic-Based Machine Learning Model Predicts Endometrial Cancer Recurrence Using Preoperative CT Radiomic Features: A Pilot Study

“…However, low-income countries may lack access to MRI [ 56 ]. Positron Emission Tomography (PET) imaging has been introduced for staging and prognosis [ 57 ], but its performance is limited in detecting lymph node metastases [ 58 ]. However, combining high-resolution diagnostic images with radiomics showed promise in predicting lymph node metastases [ 13 , 59 , 60 ].…”

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

“…Positron emission tomography (PET) scan has an excellent specificity for the preoperative assessment of lymph node metastases in endometrial carcinoma patients. Its moderate sensitivity for detecting lymph node metastases during preoperative staging probably reflects the need for a sufficient number of neoplastic cells to induce 18 F-fluoro-2-deoxy-D-glucose hypermetabolism [89][90][91][92][93][94][95][96][97][98][99][100]. The usefulness of maximal standardized uptake value in classifying patients into pre-defined riskgroups is limited [101].…”