Report from AMI: Fluorocholine PET/CT aids prostate cancer staging and management

The power of F-18 fluorocholine (FCH) as a guide for the clinical management of prostate cancer is gaining recognition. Dynamic whole-body PET/CT performed with F-18 FCH accurately assesses the extent of lymphatic involvement from prostate cancer, according to findings from two years of experience at the PET/CT center of Hospital of the Holy Sister in Linz, Austria.

A study involving preoperative staging for 49 patients and postoperative follow-up for 61 patients found that the probe is equally adept at identifying bone metastases associated with prostate cancer. Results were presented Monday by Dr. Warner Langsteger, director of nuclear medicine and endocrinology at Holy Sister, at the 2005 Academy of Molecular Imaging meeting in Orlando.

For staging, positive FCH PET/CT findings were generated for 16 of 18 cases confirmed with biopsy: 4% of the cases were downstaged mainly because of suspicious bone lesions that were negative for uptake on the FCH PET/CT scans, and 12% of the presurgical cases were upstaged.

FCH PET/CT uncovered new bone metastases in four cases, and in two cases, it helped identify positive lymph node involvement. As a result, radiation therapy was prescribed for these patients, and surgery was canceled, Langsteger said.

FCH PET/CT agreed with the laboratory finding for all 31 patients whose preoperative conditions were confirmed with postoperative histology, according to Langsteger. The procedures identified positive lymph nodes larger than 5 mm in four patients. Among these patients, two positive lymph nodes, diagnosed with histology, were not found with FCH PET/CT. Histology revealed that these metastases ranged in size from 5 mm to 8 mm.

F-18 FCH has enjoyed positive reviews elsewhere in Europe during its five-year history. Timothy R. DeGrado, Ph.D, now at Indiana University, first synthesized the probe at Duke University in 2000. During a plenary session at the 2005 European Congress of Radiology in Vienna earlier this month, Dr. Gustav K. von Schulthess, director of nuclear medicine at University Hospital in Zurich, Switzerland, predicted that F-18 FCH would be the next positron-emitting radiopharmaceutical agent to join F-18 FDG in routine clinical use.

Langsteger was also encouraged about the probe's potential. The results of his study led him to conclude that dynamic PET/CT with F-18 FCH will become a valuable noninvasive diagnostic tool for prostate cancer, especially for differential diagnoses involving lymph nodes and the ureter.