Role of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of main tumor in breast cancer in prediction of occult axillary lymph node metastasis.

Abstract

This retrospective study was done to assess the clinical significance of total lesion glycolysis (TLG) and metabolic tumor volume (MTV) of primary breast cancer using 18F-FDG PET/CT to predict positive axillary lymph node metastasis in clinically negative axillary lymph nodes in breast cancer patients. The study was carried out on 40 female breast cancer patients with clinically negative axillary lymph nodes who had undergone surgical resection of the primary breast tumor followed by sentinel lymph node biopsy only or axillary lymph node dissection along with sentinel lymph node biopsy. Occult axillary lymph node or clinically negative node is defined as no signs of axillary lymph node metastases, consisting of a negative physical examination of the axilla and preoperative axillary ultrasound or other imaging modalities Firstly, all patients were required to fast at least 6 h to yield a blood glucose level of less than 200 mg/dL prior to 18F-FDG PET/ CT. A low-dose CT was performed for attenuation correction before the PET scan. A PET scan was acquired at approximately 60 min after intravenous administration of 0.1 m/Ci FDG/Kg of 18F-FDG followed by a 10-mL quantity of normal saline. Both CT and PET images were obtained from the base of the skull to the upper thighs. Then The PET images were reconstructed and PET-CT findings and images were analyzed through measurement of standardized uptake values (SUVs), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary breast neoplastic lesion.