Choline PET and PET/CT in Primary Diagnosis and Staging of Prostate Cancer

Abstract

PET and PET/CT using [(11)C]- and [(18)F]-labelled choline derivates is increasingly being used for imaging of primary and recurrent prostate cancer. While PET and PET/CT with [(11)C]- and [(18)F]-labelled choline derivates in patients suffering from biochemical recurrence of prostate cancer has been examined in many studies that demonstrate an increasing importance, its role in the primary staging of prostate cancer is still a matter of debate.Morphological and functional imaging techniques such as CT, MRI and TRUS have demonstrated only limited accuracy for the diagnosis of primary prostate cancer. Molecular imaging with PET and PET/CT could potentially increase accuracy to localize primary prostate cancer. A considerable number of studies have examined the value of PET/CT with [(11)C]- and [(18)F]- labelled choline derivates for the diagnosis of primary prostate cancer with mixed results. Primary prostate cancer can only be detected with moderate sensitivity using [(11)C]- and [(18)F]choline PET and PET/CT. The detection rate depends on the tumour configuration. Detection is also limited by a considerable number of microcarcinomas that cannot be detected due to partial volume effects. Therefore small and in part rind-like tumours can often not be visualized. Furthermore, the differentiation between benign changes like prostatitis, high-grade intraepithelial neoplasia (HGPIN) or prostatic hyperplasia is not always possible. Therefore, at the present time, the routine use of PET/CT with [(11)C]- and [(18)F]-labelled choline derivates cannot be recommended as a first-line screening procedure for primary prostate cancer in men at risk. A potential application of choline PET and PET/CT may be to increase the detection rate of clinically suspected prostate cancer with multiple negative prostate biopsies, for example in preparation of a focused re-biopsy and may play a role in patient stratification with respect to primary surgery and radiation therapy in the future.

Keywords: PET/CT; Prostate Cancer; choline PET.

Fig 1

72 year old patient with biopsy proven prostate cancer, PSA 7,38 ng/ml, referred for [¹⁸F]FDG PET/CT for primary staging. [¹⁸F]FDG PET/CT revealed advanced disease of primary prostate cancer, iliacal lymph node metastases and bone metastasis (A 1-3) CT scan, (B 1-3) PET scan, (C 1-3) PET/CT fused images.

Fig 2

71 year old patient with biopsy proven prostate cancer, initial PSA 193 ng/ml, referred for [¹⁸F]choline PET/CT for primary staging. [¹⁸F]choline PET/CT revealed adcanced disease (primary prostate cancer, iliacal and pararectal lymph node metastases) (A 1-3) CT scan, (B 1-3) PET scan, (C 1-3) PET/CT fused images.

Fig 3

75 year old patient under of primary prostate cancer and increasing PSA> 40 ng/ml, referred for [¹⁸F]choline PET/CT for primary staging due to multiple negative biopies. [¹⁸F]choline PET/CT revealed advanced disease with multilocular prostate cancer, lymph node metastasis and bone metastasis (A 1-3) CT scan, (B 1-3) PET scan, (C 1-3) PET/CT fused images.