[1-11C]Acetate uptake is not increased in renal cell carcinoma

The purpose of this study was to investigate the potential of [1-11C]acetate (AC) as a metabolic tracer for renal cell cancer in human subjects. Twenty-one patients with suspected kidney tumours were investigated with AC and dynamic PET. AC uptake was scored on a five-step scale. Tumour localisation was known from CT/MRI. Histology was available in 18/21 patients. The results in these 18 patients are reported. AC uptake by the tumour was less than (n = 11), equal to (n = 5) or higher than (n = 2) uptake in the surrounding renal parenchyma. Histological tumour types showed a typical distribution, with a predominance of clear cell carcinomas (n = 14) and only a small number of papillary cell carcinomas (n = 2) and oncocytomas (n = 2). Only the benign oncocytomas were highly positive with AC. In most kidney tumours the AC accumulation was not higher than in normal kidney parenchyma. Therefore, AC PET cannot be recommend for the characterisation of a renal mass. (orig.)