Cholesterol Granuloma: Unusual Pitfall for Hodgkin Lymphoma Evaluation With 18F-FDG PET/CT.

ABSTRACT: Cholesterol granuloma (CG) is a foreign body-type granuloma that forms in response to cholesterol crystals. Its etiology and pathogenesis are unclear. 18F-FDG is not a tumor-specific agent. Fibroblasts, macrophages, and multinucleated giant cells also take up 18F-FDG. Like sarcoid granulomas or fibrous dysplasia, CG avidly takes up 18F-FDG and can mimic tumor involvement. We present 2 cases of histologically proven CG, which has been misinterpreted as active residual Hodgkin lymphoma lesion.

High prognostic value of 18F-FDG PET for metastatic gastroenteropancreatic neuroendocrine tumors: a long-term evaluation.

UNLABELLED: This study aimed to evaluate the long-term prognostic usefulness of (18)F-FDG PET for patients with metastatic gastroenteropancreatic neuroendocrine tumors (GEPNETs). METHODS: Thirty-eight patients with metastatic GEPNETs were prospectively enrolled. Initial check-up comprised CT scan, (111)In-pentetreotide scintigraphy (SRS), and (18)F-FDG PET. Only (18)F-FDG PET-positive lesions with a maximum standardized uptake value (SUVmax) greater than 4.5 or an SUV ratio (SUVmax tumor to SUVmax nontumoral liver tissue, or T/NT ratio) of 2.5 or greater were considered positive for prognosis-that is, indicating a poor prognosis. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Factors associated with survival were assessed with univariate and multivariate analyses, using the Cox regression model. RESULTS: Median PFS and OS were significantly higher for patients with a negative (18)F-FDG PET finding, with an OS of 119.5 mo (95% confidence interval [CI], 72-∞), than for patients with a positive (18)F-FDG PET finding (only 15 mo [95% CI, 4-27]) (P < 10(-3)). Median PFS and OS were significantly higher for the patient group that had a positive SRS than the group with a negative SRS (P = 0.0002). For patients with a positive SRS, PFS and OS were significantly shorter when the (18)F-FDG PET finding was positive: 19.5 mo (95% CI, 4-37) for PFS and 119.5 mo (95% CI, 81-∞) for OS (P < 10(-3)). In the patient group with a low-grade GEPNET and a positive SRS, PFS and OS were also significantly lower for patients with a positive (18)F-FDG PET. At 48-mo follow-up, 100% of patients who had a positive (18)F-FDG PET for disease progression (of which 47% were also SRS-positive) were deceased, and 87% of patients with a negative (18)F-FDG PET were alive (P < 0.0001). The T/NT ratio was the only parameter associated with OS on multivariate analysis. CONCLUSION: Overall, (18)F-FDG PET appears to be of major importance in the prognostic evaluation of metastatic GEPNET. A positive (18)F-FDG PET with an SUV ratio (T/NT) of 2.5 or greater was a poor prognostic factor, with a 4-y survival rate of 0%. A positive SRS does not eliminate the need for performing (18)F-FDG PET, which is of greater prognostic utility.

Diagnostic and prognostic impact of 18F-FDG PET/CT in follicular lymphoma.

PURPOSE: The aim of this study was to assess the usefulness of positron emission tomography/computed tomography in staging, prognosis evaluation and restaging of patients with follicular lymphoma. METHODS: A retrospective study was performed on 45 patients with untreated biopsy-proven follicular lymphoma who underwent 18F-fluorodeoxyglucose PET/CT (FDG PET/CT) and CT before and after chemoimmunotherapy induction treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone). RESULTS: PET/CT detected more nodal (+51%) and extranodal (+89%) lesions than CT. PET/CT modified Ann Arbor staging in eight patients (18%). Five patients (11%) initially considered as being early stage (I/II) were eventually treated as advanced stage (III/IV). In this study, an initial PET/CT prognostic score was significantly more accurate than the Follicular Lymphoma International Prognostic Index score in identifying patients with poor prognosis (i.e. patients with incomplete therapeutic response or early relapse). The accuracy of PET/CT for therapeutic response assessment was higher than that of CT (0.97 vs 0.64), especially due to its ability to identify inactive residual masses. In addition, post-treatment PET/CT was able to predict patients' outcomes. The median progression-free survival was 48 months in the PET/CT-negative group as compared with 17.2 months for the group with residual uptake (p<10(-4)). CONCLUSION: FDG PET/CT is useful for staging and assessing the prognosis and therapeutic response of patients with follicular lymphoma.

[Treatment of painful bony metastases with Samarium 153-EDTMP in prostate carcinoma]. / Traitement des metastases osseuses douloureuses par le Samarium 153-EDTMP dans le cancer de la prostate.

UNLABELLED: THE OBJECTIVE of this work is to evaluate a new therapy, the metabolic radiotherapy to the 153Samarium-EDTMP, of recent introduction in Tunisia, in the painful bony metastasis treatment observed at the patients affected of cancer of the prostate. METHODS: It is about a retrospective survey with a receding of 40 months, achieved through 45 files of patients having benefited all of this new treatment for painful bony metastases in relation with a prostatic adenocarcinoma and collected by three centers of Nuclear Medicine of the capital: the institute Salah Azaiez (state-controlled), the Center CERU (deprives) and the Military hospital (HMPIT). RESULTS: We tried to appreciate essentially four parameters: the therapeutic efficiency, the factors influencing the answer in the treatment, the toxicity of the treatment and the sources of failure. We observed a positive answer in 92,1% of the cases, this answer was complete in 36,5% of the cases. The results gotten after multiple administrations show that the cures could be repeated with results comparable to those of the first cure. The therapeutic efficiency is at least equivalent to those of the other therapeutic means, with nearly non-existent secondary effects. The only toxicity is of hematological order; it is the most often moderate and reversible with a complete recuperation at the end of 8 weeks. Besides, the effect on the pain came with an improvement of the quality of life of the patients treaties. CONCLUSION: Its precocious introduction in the taken in charge of the metastatic patients, would allow them to benefit better from its efficiency, simplicity and weak toxicity and therefore to enjoy a better quality of life.