Significance of 18F-fluorocholine PET/CT positive pulmonary lesions in prostate cancer patients

Lung uptake of fluorine-18 fluoroethyl-choline PET-CT in patients with prostate cancer

BACKGROUND

Metastatic spreading to the lungs is a negative prognostic factor in patients with prostate cancer (PC). Aim of our study was to assess the prevalence of lung PC metastases in patients with fluorine-18 fluoroethyl-choline (F-18-FECh) PET-CT positive lung lesions and the role of Gleason Score (GS) and common biochemical markers in predicting metastatic spreading to the lungs.

METHODS

We retrospectively evaluated the scans of 1283 patients ongoing (F-18-FECh) PET-CT for PC between May 2010 and July 2014. Patients with lung lesion with F-18-FECh uptake were included. Data concerning GS at diagnosis, "trigger" prostate-specific antigen (PSAtr), PSA doubling time (PSAdt), PSA velocity (PSAvel) and ongoing androgen deprivation therapy were collected. PET-CT findings were confirmed by histology or follow-up (FU) and classified as follows: inflammation, primary lung cancer or metastases from tumor other than PC, and lung metastases from PC.

RESULTS

Twenty-two patients with F-18-FECh positive lung lesion and available histology or FU were identified. PSAdt was significantly (P=0.029) shorter in patients with lung metastases from PC (median PSAdt 1.7 months, interquartile range [IQR] 1.5-4.1 months) than in patients without lung PC relapse (median PSAdt 6.7 months, IQR 3.9-7.8); PSAvel was significantly (P=0.019) higher in patients with lung metastases from PC (median PSAvel 3.2 ng/mL/month, IQR 0.65-6.65 ng/mL/month) than in patients without lung PC relapse (median PSAvel 0.3 ng/mL/month, IQR 0.2-0.5 ng/mL/month). Patients with lung metastases from PC had significantly (P=0.006) higher GS at diagnosis (median GS 8) than the other ones (median GS 7).

CONCLUSIONS

Our analysis shows that the prevalence of F-18-FECh positive lung metastases in patients with PC, especially with higher GS at diagnosis, is higher in presence of a steady increase in PSA values, confirmed by higher PSAvel and shorter PSAdt.

18F-fluorocholine PET/CT in patients with occult biochemical recurrence of prostate cancer: Detection rate, impact on management and adequacy of impact. A prospective multicentre study

Aim

To prospectively evaluate the clinical impact and the diagnostic performance of FCH-PET/CT in patients with occult biochemical recurrence of prostate cancer (PCa).

Materials and methods

Results of 179 patients (mean PSA = 7.5ng/mL) with negative/inconclusive results of pelvic-MRI and of bone-scintigraphy were analysed. To determine the impact of FCH-PET/CT on diagnostic thinking and on patient management, the referring physicians prospectively filled-in a 1^st and 2^nd questionnaire related to patient’s planned management before and after FCH-PET/CT. Based on data from a 6-month follow-up after FCH-PET/CT, an independent assessor blinded to results of FCH-PET/CT determined the adequacy of management changes motivated by FCH-PET/CT.

Results

FCH-PET/CT localised foci evocative of recurrent PCa in 59% (105/179) of patients. Results of FCH-PET/CT motivated a change in scheduled patient management in 56% (100/179) of patients; which was considered as adequate in 89% (89/100) of patients. FCH-PET/CT also led to the detection of lung cancer in two patients.

Conclusion

FCH PET/CT is a powerful tool to localise the sites of occult biochemical recurrence of PCa, leading to an adequate management change in half of patients.