Yuji Nakamoto MD, PhD, Presenter: Nothing to Disclose

Munehiro Sugiyama MD, Abstract Co-Author: Nothing to Disclose

Tatsuya Higashi MD, Abstract Co-Author: Nothing to Disclose

Takayoshi Ishimori MD, Abstract Co-Author: Nothing to Disclose

Tsuneo Saga MD, Abstract Co-Author: Nothing to Disclose

Kaori Togashi MD, Abstract Co-Author: Nothing to Disclose

Positron emission tomography (PET) with F-18-fluorodeoxyglucose (FDG) is widely used for restaging of colorectal cancer. The purpose of this study was to investigate the prognostic value of FDG-PET findings with respect to survival in post-operative patients with colorectal cancer.

Between June, 2000 and July, 2005, 239 post-operative patients with colorectal carcinoma (M:F=150:89, mean age 63 years) underwent FDG-PET scans to detect recurrence (rec) or metastases (mets). The PET images were assessed for the presence of abnormal uptake, suggesting local recurrence and/or mets. The clinical course of these patients was followed, and their clinical status was compared with their PET findings (local rec, mets to the pelvic lymph node (LN), abdominal LN, mediastinal LN, supraclavicular LN, liver, lung, or peritoneum), gender, age, and pathologic stage at initial surgery using the Kaplan-Meyer method. A stepwise Cox proportional hazard model was built using the significant variables on univariate analysis.

Eighteen patients who turned out to have other malignancies or died of other causes were excluded, and the remaining 221 patients were analyzed. At the end of 2005, among the patients with positive PET studies (n=144), 22 were alive without rec, 89 alive with rec and 33 had died. Among the patients with negative PET studies (n=77), 57 were alive without rec, 13 alive with rec and 7 had died. The factors that significantly affected patients' survival (p<0.05) were the presence of abdominal LN mets, mediastinal LN mets, liver mets, or lung mets and pathologic stage on univariate analysis. On multivariate analysis, the presence of abdominal LN mets (relative risk=3.0, p=0.0192) or lung mets (relative risk=5.1, p=0.0002) remained a significant independent predictor of mortality.

Our data indicate that the positive PET finding of abdominal lymph node or lung was an independent predictor of mortality in patients with colorectal cancer.

FDG-PET can be used not only for staging or restaging, but also for predicting patients' prognosis by its findings in patients after surgery for colorectal cancer.

Nakamoto, Y, Sugiyama, M, Higashi, T, Ishimori, T, Saga, T, Togashi, K, Prognostic Value of FDG-PET in Patients with Colorectal Cancer.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4431687.html