Prognostic Evaluation of Metastatic Castration Resistant Prostate Cancer and Neuroendocrine Prostate Cancer with [68Ga]Ga DOTATATE PET-CT

Abstract

Objectives: Prostate cancer is well known to express high levels of somatostatin receptors and preliminary data suggests that PET imaging with the somatostatin analog, [68Ga]Ga-DOTATATE, may allow for whole body staging of patients with metastatic castration resistant prostate cancer (mCRPC) and neuroendocrine prostate cancer (NePC). This study explores the utility of [68Ga]Ga-DOTATATE PET-CT to identify metastatic deposits in men with mCRPC and NePC and prognosticate disease progression. Methods: [68Ga]Ga-DOTATATE PET-CT was performed in 17 patients with mCRPC and of those, 2/17 had NePC. A semiquantitative analysis with standardized uptake values (SUV) (e.g., SUVmax, SUVmean) was performed for each metastatic lesion and reference background tissues. [68Ga]Ga-DOTATATE uptake in metastatic deposits was further classified as: mild (less than liver), moderate (up to liver average), or marked (greater than liver). Serial prostate-specific antigen measurements and patient survival were followed up to 3 years after PET imaging to assess response to standard of care treatment. Results: All patients had at least one metastatic lesion with identifiable [68Ga]Ga-DOTATATE uptake. Marked [68Ga]Ga-DOTATATE uptake was found in 7/17 patients, including both NePC patients, and all were non-responders to systemic therapy and died within the follow up period, with a mean time to death of 8.1 months. Three patients had mild [68Ga]Ga-DOTATATE uptake, and all were responders to systemic therapy and were alive 36 months after [68Ga]Ga-DOTATATE imaging. Conclusions: [68Ga]Ga-DOTATATE is able to identify mCRPC and NePC metastatic deposits, and lesions with [68Ga]Ga-DOTATATE uptake > liver may portend poor outcomes in patients with mCRPC.

PET/CT and Conventional Imaging for the Assessment of Neuroendocrine Prostate Cancer: A Systematic Review

“…A total of 3427 articles were extrapolated with the computer literature search, and by reviewing the titles and abstracts, 3414 of them were excluded because the reported data were not within the field of interest of this review. Thirteen articles were therefore selected and retrieved in full-text version [28][29][30][31][32][33][34][35][36][37][38][39][40]; no additional studies were found screening the references of these articles (Figure 1). In general, the quality assessment using QUADAS-2 evaluation underlined the presence of a high risk of bias and applicability concerns in some of these studies for patient selection, and this is mainly related to the fact that these studies were characterized by heterogeneous cohorts (Figure 2).…”

“…In general, the quality assessment using QUADAS-2 evaluation underlined the presence of a high risk of bias and applicability concerns in some of these studies for patient selection, and this is mainly related to the fact that these studies were characterized by heterogeneous cohorts (Figure 2). Among the total number of studies included in the systematic review, 10 were of a retrospective nature [28,29,[33][34][35][36][37][38][39][40], whereas 2 had a prospective design [28,29], and in 1 case, it was not specified its nature [32]. Ten studies focused on PET/CT imaging [28,37], while three studies were performed using CI [38][39][40].…”

Small Cell Neuroendocrine Carcinoma of the Prostate on 18F-DCFPyL and 18F-FDG PET/CT

“…[1][2][3][4] Small cell neuroendocrine carcinoma of the prostate has similar morphologic features to other small cell carcinomas including the lung and is often aggressive with high metastatic potential including in the viscera and soft tissue. [2][3][4] Conventional surveillance with PSA levels is challenging as they are often discordant with the volume of disease. 2,4 Furthermore, surveillance with 18 F-DCFPyL or 68 Ga-PSMA-PET may yield false-negative results as described in other cases where scanning with 18 F-FDG or 68 Ga-DOTATATE revealed lesions that were occult on 18 F-DCFPyL or 68 Ga-PSMA-PET.…”

“…There were also metastases to the bilateral lower lobes of the lungs (SUV max , up to 7.5; E), right eighth rib (SUV max ; F), and right acromion (SUV max , 11.1; G). Neuroendocrine prostate cancers typically represent transformation of androgen deprivation therapy-resistant disease, although de novo cases are also seen [1][2][3][4]. Small cell neuroendocrine carcinoma of the prostate has similar morphologic features to other small cell carcinomas including the lung and is often aggressive with high metastatic potential including in the viscera and soft tissue [2][3][4].…”

“…Neuroendocrine prostate cancers typically represent transformation of androgen deprivation therapy-resistant disease, although de novo cases are also seen [1][2][3][4]. Small cell neuroendocrine carcinoma of the prostate has similar morphologic features to other small cell carcinomas including the lung and is often aggressive with high metastatic potential including in the viscera and soft tissue [2][3][4]. Conventional surveillance with PSA levels is challenging as they are often discordant with the volume of disease 2,4.…”