Positron Emission Tomography-Computed Tomography (PET-CT) Versus No PET-CT in the Management of Potentially Resectable Colorectal Cancer Liver Metastases: Cost Implications of a Randomized Controlled Trial.

PURPOSE: To evaluate whether positron emission tomography (PET) combined with computed tomography (PET-CT) is cost saving, or cost neutral, compared with conventional imaging in management of patients with resectable colorectal cancer liver metastases. METHODS: Cost evaluation of a randomized trial that compared the effect of PET-CT on surgical management of patients with resectable colorectal cancer liver metastases. Health care use data ≤ 1 year after random assignment was obtained from administrative databases. Cost analysis was undertaken from the perspective of a third-party payer (ie, Ministry of Health). Mean costs with 95% credible intervals (CrI) were estimated by using a Bayesian approach. RESULTS: The estimated mean cost per patient in the 263 patients who underwent PET-CT was $45,454 CAD (range, $1,340 to $181,420) and in the 134 control patients, $40,859 CAD (range, $279 to $293,558), with a net difference of $4,327 CAD (95% CrI, -$2,207 to $10,614). The primary cost driver was hospitalization for liver surgery (difference of $2,997 CAD for PET-CT; 95% CrI, -$2,144 to $8,010), which was mainly a result of a longer length of hospital stay for the PET-CT arm (median, 7 v 6 days; P = .03) and a higher postoperative complication rate (20% v 10%; P = .01). Baseline characteristics were similar between groups, including the number of liver segments involved with cancer, number of segments resected, and type of liver resection performed. No difference in survival was detected between arms. CONCLUSION: PET-CT was associated with limited clinical benefit and a nonsignificant increased cost. Universal funding of PET-CT in the management of patients with resectable colorectal cancer liver metastases does not seem justified.

Effect of PET before liver resection on surgical management for colorectal adenocarcinoma metastases: a randomized clinical trial.

IMPORTANCE: Patients with colorectal cancer with liver metastases undergo hepatic resection with curative intent. Positron emission tomography combined with computed tomography (PET-CT) could help avoid noncurative surgery by identifying patients with occult metastases. OBJECTIVES: To determine the effect of preoperative PET-CT vs no PET-CT (control) on the surgical management of patients with resectable metastases and to investigate the effect of PET-CT on survival and the association between the standardized uptake value (ratio of tissue radioactivity to injected radioactivity adjusted by weight) and survival. DESIGN, SETTING, AND PARTICIPANTS: A randomized trial of patients older than 18 years with colorectal cancer treated by surgery, with resectable metastases based on CT scans of the chest, abdomen, and pelvis within the previous 30 days, and with a clear colonoscopy within the previous 18 months was conducted between 2005 and 2013, involving 21 surgeons at 9 hospitals in Ontario, Canada, with PET-CT scanners at 5 academic institutions. INTERVENTIONS: Patients were randomized using a 2 to 1 ratio to PET-CT or control. MAIN OUTCOMES AND MEASURES: The primary outcome was a change in surgical management defined as canceled hepatic surgery, more extensive hepatic surgery, or additional organ surgery based on the PET-CT. Survival was a secondary outcome. RESULTS: Of the 263 patients who underwent PET-CT, 21 had a change in surgical management (8.0%; 95% CI, 5.0%-11.9%). Specifically, 7 patients (2.7%) did not undergo laparotomy, 4 (1.5%) had more extensive hepatic surgery, 9 (3.4%) had additional organ surgery (8 of whom had hepatic resection), and the abdominal cavity was opened in 1 patient but hepatic surgery was not performed and the cavity was closed. Liver resection was performed in 91% of patients in the PET-CT group and 92% of the control group. After a median follow-up of 36 months, the estimated mortality rate was 11.13 (95% CI, 8.95-13.68) events/1000 person-months for the PET-CT group and 12.71 (95% CI, 9.40-16.80) events/1000 person-months for the control group. Survival did not differ between the 2 groups (hazard ratio, 0.86 [95% CI, 0.60-1.21]; P = .38). The standardized uptake value was associated with survival (hazard ratio, 1.11 [90% CI, 1.07-1.15] per unit increase; P < .001). The C statistic for the model including the standardized uptake value was 0.62 (95% CI, 0.56-0.68) and without it was 0.50 (95% CI, 0.44-0.56). The difference in C statistics is 0.12 (95% CI, 0.04-0.21). The low C statistic suggests that the standard uptake value is not a strong predictor of overall survival. CONCLUSIONS AND RELEVANCE: Among patients with potentially resectable hepatic metastases of colorectal adenocarcinoma, the use of PET-CT compared with CT alone did not result in frequent change in surgical management. These findings raise questions about the value of PET-CT scans in this setting. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00265356.

Prevalence of "silent" pulmonary emboli in adults after the Fontan operation.

OBJECTIVES: The study was done to determine the prevalence of pulmonary emboli (PE) in asymptomatic adult Fontan patients and to identify the risk factors associated with PE. BACKGROUND: Right atrial thrombi and systemic thromboembolic complications have been reported after the Fontan procedure. However, the frequency of silent PE in this patient population is not known. METHODS: All consecutive adult Fontan patients attending the adult congenital clinic over a six-month period underwent ventilation-perfusion (VQ) scanning and blood testing for thrombophilia tendency. If the VQ scan showed an intermediate or high probability for PE, a computerized tomography (CT) pulmonary angiogram was performed to confirm the presence of PE. RESULTS: Thirty patients (mean age 26 +/- 7 years, 57% men) were included in this study. Five (17%) adult Fontan patients had an intermediate or high probability for PE on VQ scan, all of which were confirmed on CT pulmonary angiography. No patient had a thrombophilia tendency. Pulmonary emboli were not present in any patients (30%) taking warfarin. Late age at time of Fontan operation (19 +/- 6 years vs. 11 +/- 6 years, p = 0.012) and type of Fontan anatomy (p = 0.001) were associated with increased risk of silent PE. CONCLUSIONS: Seventeen percent of adult patients with Fontan procedure have clinically silent PE. The long-term hemodynamic implications of this with respect to Fontan attrition over time are unknown. Large randomized prospective studies looking at anticoagulation therapy in all Fontan patients are urgently needed.