68Ga-DOTANOC somatostatin receptor PET-CT imaging in multiple myeloma.

Multiple myeloma cells express somatostatin receptors, and somatostatin receptor scintigraphy with 111In-pentetreotide has been used for imaging multiple myeloma with variable success. We here present 68Ga-DOTANOC somatostatin receptor PET-CT findings in a 57-year-old man with multiple myeloma. PET-CT showed 2 expansile lytic lesions with increased 68Ga-DOTANOC. This case highlights the potential use of 68Ga-DOTANOC PET-CT as an alternative imaging modality in multiple myeloma.

Linfoma primario del sistema nervioso central con linfomatosis cerebri en un niño inmunocompetente: hallazgos de la MRI y 18F-FDG PET-TC / Primary central nervous system lymphoma with lymphomatosis cerebri in an immunocompetent child: MRI and 18F-FDG PET-CT findings

El linfoma primario del sistema nervioso central (LPSNC) es extremadamente raro en niños inmunocompetentes. Presentamos los hallazgos de la imagen de resonancia magnética (MRI) y de tomografía por emisión de positrones-tomografía computarizada (PET-TC) con 18F-FDG en un niño inmunocompetente de 14 años de edad. En este paciente el LPSNC se asoció con linfomatosis cerebri. Estar familiarizado con los hallazgos de esta rara afectación mejorará la confianza diagnóstica del médico nuclear y evitará un diagnóstico erróneo (AU)

Primary central nervous system lymphoma (PCNSL) is extremely rare in immunocompetent children. We present the magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) findings of such a case in a 14-year old immunocompetent boy. In this patient, PCNSL was associated with lymphomatosis cerebri. Familiarity with the findings of this rare condition will improve the diagnostic confidence of the nuclear radiologist and avoid misdiagnosis (AU)

Primary central nervous system lymphoma with lymphomatosis cerebri in an immunocompetent child: MRI and 18F-FDG PET-CT findings.

Primary central nervous system lymphoma (PCNSL) is extremely rare in immunocompetent children. We present the magnetic resonance imaging (MRI) and (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) findings of such a case in a 14-year old immunocompetent boy. In this patient, PCNSL was associated with lymphomatosis cerebri. Familiarity with the findings of this rare condition will improve the diagnostic confidence of the nuclear radiologist and avoid misdiagnosis.

Utility of (18)F-FDG PET-CT in staging and restaging of patients with malignant salivary gland tumours: a single-institutional experience.

OBJECTIVE: The aim of this study was to evaluate the clinical utility of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) in staging and restaging of patients with malignant primary salivary gland tumours. METHODS: Data pertaining to 30 patients (age: 43.8±16.8 years; male/female: 20/10) with histopathologically proven malignant primary salivary gland tumours who underwent 36 F-FDG PET-CTs were retrospectively analysed. Ten PET-CTs were performed for staging and 26 for restaging. The primary site was the parotid gland in 22 patients, the submandibular gland in seven and the minor salivary gland in one patient. (18)F-FDG PET-CT images were revaluated by two nuclear medicine physicians in consensus. Findings were grouped into local disease, nodal disease and distant metastasis. Results were compared with those of conventional imaging modalities [CIM (CT/ultrasound/bone scintigraphy)] when available (n=28). Clinical or imaging follow-up (minimum 6 months) data along with histopathological information (when available) were taken as the reference standard. RESULTS: Overall, 25 PET-CTs were positive and 11 were negative for disease. (18)F-FDG PET-CT showed local disease in 21 patients, nodal disease in 17 and distant metastasis in nine (lungs, four; liver, three; bones, four; and thyroid, one). Twenty-three PET-CTs were true positive, nine were true negative, two were false positive and two were false negative. The overall sensitivity of (18)F-FDG PET-CT was 92%, specificity was 82%, positive predictive value was 92%, negative predictive value was 82% and accuracy was 89%. No significant difference was seen in the accuracy of PET-CT between the staging and restaging groups (100 vs. 85%; P=0.468). In patients for whom comparable CIM data were available (n=28), PET-CT did not show any significant advantage over CIM (P=0.012) but was more specific (71 vs. 43%). CONCLUSION: (18)F-FDG PET-CT shows high accuracy in staging and restaging of patients with malignant primary salivary gland tumours. It is more specific than CIM for this purpose.

Primary gastric lymphoma: utility of 18F-fluorodeoxyglucose positron emission tomography-computed tomography for detecting relapse after treatment.

The purpose of this study was to evaluate the role of 18F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) in detecting relapse in patients with primary gastric lymphoma (PGL) post-treatment. Data of 39 previously treated patients with PGL (age: 50.3 ± 13.8 years; male: 24) who underwent 71 (18)F-FDG PET-CT studies for suspected relapse (n = 53) or routine follow-up (n = 18) were retrospectively evaluated. PET-CT images were evaluated both qualitatively and quantitatively (standardized uptake value [SUVmax]). A combination of clinical/imaging follow-up, endoscopy and/or histopathology was taken as the reference standard. The per patient based sensitivity of PET-CT was 96%, specificity 91% and accuracy 93%. The lymph node was the commonest site of relapse on PET-CT. Mean lesion SUVmax was 5.9 ± 3.1 (2.3-13.6). Accuracy was similar in suspected relapse and routine follow-up groups (90.5% vs. 100%; p = 0.409). Based on the data, (18)F-FDG PET-CT appears to be highly accurate for the detection of relapse in patients with PGL post-treatment.

18F-FDG PET-CT for detecting recurrent gastric adenocarcinoma: results from a Non-Oriental Asian population.

OBJECTIVE: To evaluate the utility of fluorine-18 fluorodeoxyglucose (18F-FDG) PET-CT in the diagnosis of recurrent gastric adenocarcinoma in a Non-Oriental Asian population. METHODS: In this retrospective analysis, data from 72 Non-Oriental Asian patients, who underwent 93 18F-FDG PET-CT studies, were evaluated. All patients had histopathologically proven gastric adenocarcinoma, for which they had undergone primary treatment. PET-CT was performed for suspected recurrence or for post-therapy surveillance. PET-CT findings were analysed on a per-patient and per-region basis (local/lymph node/liver/lung/bone/others). A combination of clinical follow-up (minimum 6 months; range: 6-36 months), imaging follow-up and/or histopathology (when available) was taken as the reference standard. Sensitivity, specificity and predictive values were calculated for PET-CT on both a per-study and per-lesion basis. RESULTS: The mean patient age was 52.8 ± 11.8 years (male/female: 52/20). Out of 93 PET-CT studies, 56 (60.2%) were positive and 37 (39.8%) were negative for recurrent disease. On per-study-based analysis, 18F-FDG PET-CT has a sensitivity, specificity and accuracy of 95.9, 79.5 and 88.1%, respectively. The accuracy of 18F-FDG PET-CT was 89.2% for local recurrence, 94.6% for lymph nodes, 96.7% for liver, 96.7% for lung, 98.9% for bone and 98.9% for other sites. The accuracy of 18F-FDG PET-CT was lower for local recurrence as compared with that for liver (P=0.012) and bone (P=0.012). No significant difference was found in the diagnostic accuracies for other regions. CONCLUSION: 18F-FDG PET-CT is highly sensitive and specific for detecting recurrence in patients with gastric adenocarcinoma. It shows high accuracy both on a per-patient and per-lesion basis.