Abstract
201
Objectives To evaluate the usefulness of PET scan in oncological patient for differentiating malignant adrenal lesions from benign using quantitative (SUVmax) value
Methods We evaluate retrospectively 107 oncological patients (M=71, F=36) who underwent PET scan and regional CT scan within 1 months of PET scan and had to find the adrenal lesion on PET scan. Out of 107 patients, 41 patients had NSCLC, 3 patients -small cell lung Ca, 22 patients - RCC, 10 patients- NHL, 10 patients- Ca breast and 21 patients- various other cancers. Out of 107 patients, 53 patients were undergoing PET scan for initial staging, 27 patients-detection of recurrence, 27 patients- therapy response evaluations.
Results Final diagnosis for malignant lesion was based on histology examination-26 patients; follow up PET scan after therapy-35 patients, wide spread metastasis in PET scan and clinical follow up-46 patients. Based on these features, 12 patients were finally diagnosed as benign adrenal lesions and 95 patients as malignant adrenal lesions. The range of SUVmax was 1.3 to 22 with average of 6.4. The mean diameter of adrenal lesion was 2.6 cm (range, 0.7-8.6 cm) on regional CT. The sensitivity, specificity and accuracy for diagnosis of malignant adrenal lesions by using SUVmax > 3 as cut off was 97 %, 77% and 93 % for PET scan and by using size >1.5 cm as cut off was 65%, 21% and 60 % respectively for CT scan.
Conclusions A PET scan is a highly sensitive and accurate method for differentiating malignant adrenal lesion from benign by using SUVmax as compared to regional CT scan based on size. By using this we could be avoids further evaluation of adrenal lesions and changes the management in oncological patients.