RESUMO
Characterizing a pancreatic or periampullary mass lesion as benign or malignant on conventional imaging is difficult due to overlapping morphological features. 18F-FDG PET/CT is a molecular imaging technique with reportedly higher sensitivity and specificity in the differentiation of benign and malignant pancreatic and periampullary masses. In this prospective study, we evaluated the utility of 18F-FDG PET/CT in patients with recently diagnosed pancreatic and periampullary masses. Based on FDG uptake pattern, diffuse or absent uptake was considered benign and focal increased uptake as malignant. Among the 32 patients included in the study, pathological examination confirmed 25 as positive for malignancy and the remaining 7 as benign etiology. Based on FDG uptake pattern, sensitivity, specificity, PPV, NPV, and accuracy of the study were 92%, 42.8%, 85.2%, 60%, and 81.3% respectively. 18F-FDG PET/CT had a statistically significant higher detection rate in the evaluation of regional lymph nodes and distant organ metastases compared to radiological imaging. In 7/25 (14%) malignant cases, 18F-FDG PET/CT detected additional distant metastases which were not detected by conventional imaging and thus resulting in change in management from curative resection to palliative therapy. To conculde, 18F-FDG PET/CT uptake pattern can characterize pancreatic and periampullary masses as benign or malignant with a relatively good accuracy. Using 18F-FDG PET/CT for initial staging of pancreatic and periampullary cancer helps in appropriate staging and optimal selection of treatment modality compared to conventional imaging techniques.
RESUMO
INTRODUCTION: Breast cancer is the most common malignancy among women all over the world, which accounts to 25% of all cancers. In known cases of breast cancer, the risk of developing another denovo malignancy is more when compared to low risk groups, which might be due to common environmental risk factors, treatment induced risk factors, Genetic susceptibility for mutations, presence of cancer syndromes or better detection due to close surveillance. OBJECTIVE: To study the profile of Metachronous 2nd primary malignancies suspected on 18F-FDG PET CT in known Breast cancer patients. In this Retrospective study from January 2014 to April 2018, all the consecutive patients with known Breast cancer, who were referred to Nuclear Medicine department for 18F- FDG PET CT for follow up evaluation were included. Suspected 2nd primary malignancies were correlated with Histopathological examination (HPE). RESULTS: During the study period, a total of 233 Breast cancer patients (all are females), with a mean age of 54.2+13.4 years were studied. On 18F-FDG PET CT scan, suspicion for 2nd primary malignancy was observed in 37 patients. HPE was done in 28/37 patients at the site of suspected lesions. 15/28 were positive for second malignancy, and remaining 13/28 were either a benign pathology or a part of metastatic disease from the primary breast cancer. The sites of 2nd primary malignancies included Contralateral breast in 8/15 (53.3%), Ovary in 2/15 (13.3%), Endometrium in 2/15 (13.3%), Lung in 1/15 (6.6%), Stomach in 1/15 (6.6%) and Urinary bladder in 1/15 (6.6%) patients respectively. The incidence of metachronous 2nd primaries in breast cancer is 67.3 per 1000 breast cancer patients. CONCLUSION: Metachronous second primary cancers in breast cancer patients are not very rare. A high imaging suspicion on 18F-FDG PET CT helps in early detection of 2nd primary cancer, thereby facilitating early and appropriate management.
