TY - JOUR T1 - Usefulness of positron emission tomography (PET/CT) with 18F-FDG in patients with malignant testicular germ cells tumour JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1409 LP - 1409 VL - 53 IS - supplement 1 AU - Hugo Lavados AU - Rossana Pruzzo AU - Horacio Amaral AU - Arquimides Rodriguez AU - Francisca Redondo AU - Alejandra Pizarro AU - Ivan Pinto AU - Barbara Monje Y1 - 2012/05/01 UR - http://jnm.snmjournals.org/content/53/supplement_1/1409.abstract N2 - 1409 Objectives PET/CT is a noninvasive tool that visualizes metabolic processes in the study of cancer patients. In testicular cancer it has shown utility in staging, re-staging and therapy control and can be especially useful to differentiate active disease from fibrosis. Our objective was to describe our experience in FDG-PET/CT for staging, re-staging and treatment control in patients with malignant germ cell tumors. Methods From September 2005 to December 2010 103 studies performed in 79 patients with proven germ cell malignancy for staging, re-staging and treatment control. Mean age 34 years (range 17-63). Histopathology results and folow up from all patients were obtained. Tumors were classified as seminomatous, and nonseminoma. Results were based on histology and/or clinical follow up. Median follow up was 32.5 months (range 12-72). Visual assessment and a SUV max 2.5 cutoff were used to determine uptake in residual masses. 17 studies were included for evaluation of residual masses post chemotherapy. Nonseminoma in 53 patients (67%) and 26 seminomas (33%). Re-staging 60.2%, treatment control 33% and staging 6.8%. Results PET/CT detected metastases in 29 of 35 patients (82.8%) and excluded in 40 of 44 patients (90.9%), sensitivity (S) 89%, specificity (Spe) 88%, positive predictive value (PPV) 80% and negative predictive value (NPV) 94%. In the nonseminoma group: S 83%, Spe 86%, PPV 83% and NPV 86% and for seminomas: S100%, Spe 88%, PPV 82% and NPV 100%. Uptake was found in 7 of 17 cases (41.2%) refered for post chemotherapy residual mass evaluation with S 75%, Spe 88%, PPV 80% and NPV 93%. Two false negative cases in teratoma patients and four false positive because of recent chemotherapy. Conclusions In our series 18F-FDG PET/CT was useful for re-staging, therapy control, staging and excluding viable residual masses post chemotherapy in testicular cancer, specially in the seminoma group. False positive results due to the early inflammatory process after recent chemotherapy should be considered ER -