F-18 FDG PET/CT in the assessment of patients with unexplained CEA rise after surgical curative resection for colorectal cancer.

PURPOSE: We evaluated the role of quantitative assessment by maximum standardized uptake value (SUVmax) on F-18 fluorodeoxyglucose [F-18]FDG positron emission tomography/computed tomography (PET/CT) in stratifying colorectal cancer (CRC) patients with unexplained carcinoembryonic antigen (CEA) rise after surgical curative resection. MATERIAL AND METHODS: Forty asymptomatic patients (mean age, 64 ± 12 years) with previous CRC and current serum CEA levels >5 ng/ml underwent [F-18] FDG PET/CT 13 ± 3 months after complete surgical resection. The SUVmax was registered on anastomosis and peri-anastomotic tissue lesions, if present. The patients were followed for 24 ± 9 months thereafter. Re-intervention, evidence of newly discovered distant metastases, and death were recognized as main events and constituted surrogate end points. The receiver-operator-curve (ROC) analysis was performed to estimate the optimal SUVmax cut-off to predict patients at high risk of main events. PET/CT results were then related to disease outcome (overall survival; OS). RESULTS: The mean SUVmax at the anastomotic site was 6.2 ± 3 (range 2.6-15). At multivariate logistic regression analysis, the anastomotic SUVmax remained as the only significant contributor to the prediction of the events (p = 0.004; OR 1.97). The ROC analysis recognized that the optimal threshold of SUVmax to differentiate patients was 5.7. A worse OS was observed in patients presenting with a SUVmax greater than 5.7 as compared to those having lesser (median survival: 16 vs. 31 months; p = 0.002). CONCLUSIONS: The quantitative assessment by SUVmax on [F-18]FDG PET/CT may be helpful in patients presenting with unexplained CEA rise after curative resection of CRC, by identifying those at risk of main events.

Our experience on pain palliation of bone metastasis with Sr-89 or Sm-153 in cancer patients resistant to a conventional analgesic therapy. A retrospective study.

OBJECTIVES: These retrospective study is aimed to evaluate the efficacy of therapy with Stronthium-chloride 89 (89SrCl) and Samarium 153 conjugated with ethylenediaminetetramethylene phosphonic acid (153Sm-EDTMP) in the palliation of bone pain due to metastatic malignancy. MATERIALS AND METHODS: The study refers to a presentation sample of 27 patients with bone metastases caused by different cancers (16 prostate, 5 breast, 6 lung) who were enrolled and followed-up for 11.5 +/- 6.3 months. 89SrCl (150MBq) was administered in 17 pts, 153Sm-EDTMP (37 MBq/Kg) in 10 pts. All patients showed multiple metastatic sites of 99Tc-HDP uptake documented by a standard bone scintigraphy. Effectiveness of treatment was evaluated by questionnaires about pain and quality of life, Karnofsky index, specific cancer markers, a post-treatment bone scintigraphy. Presence of flare reaction and haematological toxicity were evaluated too. RESULTS: Questionnaire scores decreased both in patients treated with 89SrCl and in those given 153Sm-EDTM, without significant difference. Karnofsky index significantly increased only in patients with prostate cancer. After therapy, there were no significant changes of tumor marker levels, neither in bone scintigraphic pattern. Flare reaction occurred in 44% of the cases within 2 weeks from the therapy. Remarkable variations of platelets and leukocytes occurred in 33.3% and 18.5% of patients, respectively, independently of the radiopharmaceutical used, but reversed within 6 weeks after therapy. CONCLUSIONS: Radionuclide therapy with bone-seeker agents 89Sr and 153Sm in the palliation of painful bone metastases allows a partial/total relief of pain with an improvement of quality of life. No tumoricid effect was found. Haematological toxicity was limited and reversible. Patients with prostate cancer seem to have a higher response rate.

A finding of myocardial uptake at a bone scintigraphy with Tc-99m HDP.

We present a patient admitted to our Department for a Tc-99m HDP three-phase bone scintigraphy to evaluate a hip prosthesis. Delayed images showed diffuse myocardial uptake at whole body scan. In such cases, several diseases should be considered in the differential diagnosis.