ABSTRACT
Despite the move toward molecular diagnostics, our clinical imaging paradigms for diagnosing cancer and for monitoring cancer therapy have largely remained at the anatomical rather than the cellular or molecular level. In order to monitor the response to treatment in prostate cancer, RECIST (Response Evaluation Criteria in Solid Tumors) criteria, which are based on anatomic size, are still used. Ga-68 prostate-specific membrane antigen (PSMA) has been introduced in 2012, but its use has been rapidly spread over the last 6 years. Ga-68 PSMA PET/CT imaging is an area of increasing interest and has taken over the traditional role of CT and bone scintigraphy in monitoring the chemotherapeutic response of patients with prostate cancer. There are some studies showing that the metabolic tumor parameters obtained by Ga-68 PSMA, such as whole-body PSMA tumour volume and whole-body total lesion PSMA, are promising compared to CT. Multimodel imaging combining morphological and molecular information is important not only for diagnostic accuracy but also for evaluating treatment response. However, prospective validation studies are required to elicit the full potential of metabolic parameters derived from Ga-68 PSMA PET/CT imaging and to adapt to the PERCIST criteria.
References
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