Comparison of absolute renal uptake by using Tc-99m MAG-3 and Tc-99m DMSA.

PURPOSE: The purpose of this study is to compare the value of absolute renal uptake (ARU %) in patients by using Tc-99m MAG-3 and Tc-99m DMSA scan. MATERIAL AND METHODS: Absolute renal uptake is calculated using Tc-99m MAG-3 and Tc-99m DMSA in renal scintigraphy, Itoh and Tauex kidney depth methods used, respectively. n = 40 adult patients of both genders were included. All patients underwent Tc-99m MAG-3 and Tc-99m DMSA, respectively. RESULTS: The values of ARU (%) were calculated separately in selected patients n = 40, (left = 17, right = 23 normal functioning kidneys) by MAG-3 and DMSA. Absolute renal uptake (%) of Tc-99m MAG-3 in left kidneys was found to be 15.2 ±â€…3.4, with spilt renal function 79.2 ±â€…14.7 and ARU (%) in right kidneys 16.2 ±â€…3.4 with spilt renal function 77.5 ±â€…19. Absolute renal uptake of Tc-99m DMSA in left kidneys was 17.5 ±â€…3.2 and in right kidneys 17.9 ±â€…4.5 with spilt renal function 81.8 ±â€…10.7 and 79.3 ±â€…13.8 for left and right kidney, respectively. Statistical analysis showed strong Pearson correlation. CONCLUSION: Absolute renal uptake % was found to be more reliable in cases of bilateral compromised kidneys. ARU (%) calculated by Tc-99m MAG-3 solely can be used as predictor of renal function. The use of Tc-99m MAG-3 has more advantages than Tc-99m DMSA alone in renal scintigraphy as dynamic scintigraphy gives less radiation burden to patient, more information regarding renal function, and shorter stay time at hospital in comparison to static renal imaging. SRF % is less reliable than ARU (%).

Gastric Metastasis from Invasive Lobular Breast Cancer, Resembling Primary Gastric Cancer.

Invasive lobular carcinoma (ILC) is the second most common subtype of invasive breast cancer and sometimes presents with an unusual metastatic pattern. Its gastric metastasis is difficult to differentiate from primary adenocarcinoma. This report presents a case of breast ILC for which the initial presentation was gastric metastasis. A 62-y-old woman presented with gastric outlet obstruction secondary to a gastric mass that had been diagnosed on upper gastrointestinal endoscopy and biopsy. The patient had been referred for 18F-FDG PET/CT for staging. The baseline 18F-FDG PET/CT scan demonstrated extensive axillary nodal and gastric metastases with a breast mass, which raised suspicion of a primary breast carcinoma. Distinguishing primary gastric adenocarcinoma from metastatic breast ILC is essential, considering that the 2 diagnoses lead to divergent treatments. Therefore, this entity needs to be considered in the differential diagnosis in clinical practice.