F-18 FDG PET/CT quantization parameters as predictors of outcome in patients with diffuse large B-cell lymphoma.

AIM: We evaluated the prognostic significance of standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) obtained by F-18 FDG PET/CT (PET/CT) in patients with diffuse large B-cell Lymphomas (DLBCL) presenting intermediate IPI score. MATERIAL AND METHODS: Fifty-two patients (61 ± 13 yr) underwent PET/CT before the first-line chemotherapy. The mean SUVmax value, the summed MTV (cm(3) ; 42% threshold), and the cumulative TLG (g) were registered. The patients were followed up 18 months thereafter (range 3-41 months). The PET/CT results were compared to the event-free survival (EFS). RESULTS: At univariate analysis, SUVmax and lactate dehydrogenase (LDH) levels were predictive, but discordantly. The Kaplan-Meier survival analysis for SUVmax showed a significant better EFS in patients presenting higher values as compared to those having lesser (P = 0.0002, HR 0.13). Summed MTV and cumulative TLG were not suitable for predicting EFS. CONCLUSION: Despite the availability of new tools for the quantitative assessment of disease activity on PET/CT, the SUVmax rather than MTV and TLG remains the only predictor for EFS in DLBCL patients. The magnitude of glycolytic activity rather than the amount of metabolically active burden holds a predominant value for determining the response to chemotherapy in DLBCL.

Maculopapular sarcoidosis: the importance of skin signs.

Sarcoidosis is a multisystem disease that affects the skin in 20 to 30% of cases. Skin findings are often the initial presenting signs, and cutaneous sarcoidosis may appear with a wide variety of lesions; it is often considered an imitator of many other skin diseases. Clinical appearance and specific dermoscopic criteria, confirmed by a typical pathology, may guide to the correct diagnosis. We report the case of a man affected by maculo-papular sarcoidosis on the back, in which the detection of cutaneous lesions was the initial step to determine the systemic nature of the disease.

Prognostic value of interim 18F-FDG PET in patients with diffuse large B-Cell lymphoma: SUV-based assessment at 4 cycles of chemotherapy.

UNLABELLED: Interim (18)F-FDG PET (after 1-4 cycles of chemotherapy) may be useful for tailoring a risk-adapted therapeutic strategy in lymphoma. The purpose of this study was to investigate whether semiquantification of standardized uptake values (SUVs) may help to improve the prognostic value of (18)F-FDG PET, compared with visual analysis, after 4 cycles of chemotherapy. METHODS: In a previous report, we showed that a 65.7% reduction in maximal SUV (SUVmax) between baseline (PET0) and 2 cycles of chemotherapy (PET2) better predicted event-free survival in 92 prospective patients with diffuse large B-cell lymphoma, by reducing false-positive interpretation of visual analysis. Eighty patients also underwent (18)F-FDG PET after induction had been completed, at 4 cycles of chemotherapy (PET4). Images were interpreted visually (as negative or positive) and by computing the optimal percentage of SUVmax reduction between PET0 and PET4. Survival curves were estimated using Kaplan-Meier analysis and compared using the log-rank test. Median follow-up was 41 mo. RESULTS: With visual analysis, the 2-y estimate for event-free survival was 82% in the PET4-negative group, compared with 25% in the PET4-positive group (P < 0.0001, accuracy of predicting event-free survival, 81.3%). An optimal cutoff of 72.9% SUVmax reduction from PET0 to PET4 yielded a 2-y estimate for event-free survival of 79% in patients with reduction of more than 72.9%, versus 32% in those with reduction of 72.9% or less (P < 0.0001; accuracy of predicting event-free survival, 77.5%). CONCLUSION: Although SUV semiquantification helps reduce false-positive interim (18)F-FDG PET interpretations at 2 cycles, its performance is equivalent to visual analysis at 4 cycles, when most of the therapeutic effect has occurred upstream. This approach may be useful for objectively tailoring consolidation strategies.

F-18 FDG PET/CT metabolic tumor volume predicts overall survival in patients with disseminated epithelial ovarian cancer.

OBJECTIVE: We evaluated the prognostic impact of quantitative assessment by maximum standardized uptake value (SUVmax), metabolic tumour volume (MTV) and tumour lesion glycolysis (TLG) on [F-18] FDG PET/CT for patients with peritoneal carcinomatosis from epithelial ovarian cancer (EOC). METHODS: Thirty-one patients with EOC underwent PET/CT for an early restaging after cytoreductive surgery, having been diagnosed with carcinomatosis (before chemotherapy). The SUVmax, MTV (cm3; 42% threshold) and TLG (g) were registered on residual peritoneal lesions. The patients were followed up 20±12months thereafter. The PET/CT results were compared to overall survival (OS). RESULTS: The Kaplan-Meier survival analysis for the SUVmax did not reveal significant differences in OS (p=0.48). The MTV survival analysis showed a significant higher OS in patients presenting with a higher tumour burden than those with less tumour burden (p=0.01; 26 vs. 14 months), whereas TLG exhibited a similar trend though not significant (p=0.06). Apart from chemo-resistance, the higher the MTV, the better will be the response to chemotherapy. CONCLUSIONS: Quantitative assessment by MTV rather than by SUVmax and TLG on PET/CT may be helpful for stratifying patients who present with peritoneal carcinomatosis from EOC, in order to implement the appropriate therapeutic regimen.

Should patients with remnants from thyroid microcarcinoma really not be treated with iodine-131 ablation?

UNLABELLED: Remnant ablation by radioiodine is generally not recommended in patients presenting uni- or multifocal cancer <1 cm, in the absence of other higher risk features. We retrospectively studied low-risk patients (pts) with differentiated thyroid cancer (DTC) less than 1 cm recruited for radioiodine therapy (RAI). METHODS: 91 pts (79 women, age 48.4 ± 12 yrs) with DTC were enrolled for RAI. Patients underwent pre-therapy ultrasonography (US), those with suspected/ambiguous lymph-nodes were excluded and proposed for cytology. Treated pts underwent post-therapeutic whole body scan (WBSt) completed by neck/chest SPECT/CT, when necessary (e.g. evidence of uptake outside of thyroid bed). A target lesion on SPECT/CT was defined as an identifiable lymph-nodal site presenting a matched significant iodine uptake. The patients were followed up for 14 ± 2 months thereafter. RESULTS: All pts/cancers were pT1. The mean histological diameter was 0.68 ± 0.23 cm. Six patients were excluded because of suspected nodal involvement at US. Thirty (35 %) out of 85 pts had suspicious WBSt as per lymph-nodal involvement which was confirmed at the subsequent SPECT/CT acquisition in most part of pts (26/30; 86 %). Overall detected target lesions was 34, and nine (26 %) had interim positive fine needle cytology. CONCLUSIONS: a significant part of low risk DTC patients, for whom RAI is not recommended, presents an incidental suspicion of lymph-nodal involvement at WBSt confirmed by subsequent SPECT/CT. Such setting would have not been treated by I-131.

Impact of ¹8F-fluoride PET-CT on implementing early treatment of painful bone metastases with Sm-153 EDTMP.

UNLABELLED: This study evaluated the diagnostic impact of using skeletal (18)F-fluoride PET/CT on patients with painful bone metastases to schedule an early palliative radionuclide treatment. METHODS: The skeletal involvement from prostate cancer metastases was assessed by both (99m)Tc-diphosphonate bone scan (BS) and (18)F-fluoride PET/CT within four weeks in 24 patients (67.7 ± 5.1 years) suffering from a borderline degree of bone pain for which radionuclide palliation was not shortly planned for administration. The BS and (18)F-fluoride PET/CT results were compared, assessing the number and extension of the skeletal sites involved. Afterward, the patients were randomly assigned either to the study group (N=12) receiving radionuclide therapy (Samarium-153 EDTMP) or to the control group (N=12) not receiving radionuclide therapy. The short-term results from the radionuclide palliation group (evaluated with a visual analogue scale) were compared with the controls. RESULTS: Overall, at BS, 7.6 ± 1.4 sites were considered metastatic, involving at least 5 ± 1 body regions. At (18)F-fluoride PET/CT, 116 ± 19 sites presented metastatic involvement with 12/12 body regions concerned. No differences were found in regards to either the number of metastatic sites or regions at both BS and (18)F-fluoride PET/CT between the study group and controls (p=ns). At CT, 88 blastic metastases were identified, whereas 110 were mainly lytic. Most of mainly lytic lesions were not detectable at BS. The reduction in total discomfort and bone pain in the study group was significantly greater than in the controls (p<0.0001). CONCLUSION: Sm-153 EDTMP therapy should be considered for patients with early bone pain from prostate cancer even if their BS only indicates a few metastases before the initiation of a severe pain syndrome. (18)F-fluoride PET/CT may be helpful in deciding if the implementation of bone pain palliation using bone-seeking radionuclides at pain onset is necessary.

Dopamine transporter imaging under high-dose transdermal nicotine therapy in Parkinson's disease: an observational study.

OBJECTIVES: Nicotine therapy might improve the course of Parkinson's disease. This observational study evaluated the performance of dopamine transporter imaging in follow-up patients under nicotine therapy. METHODS: Six Hoehn and Yahr stage III patients underwent 123I-FP-CIT imaging prior to, 3 months, and 1 year after the onset of nicotine therapy. Nicotine was administered transdermally with increasing daily doses during 3 months (up to 105 mg/day) and decreased progressively. On co-registered magnetic resonance imaging, striatal regions of interest were drawn and binding potentials of 123I-FP-CIT were calculated.Changes in Unified Parkinson's Disease Rating Scale-III over time were compared with binding potentials using regression analysis. RESULTS: All patients improved motor scores at 3 months (-65 +/- 22% 'off', -89 +/- 12% 'on') and most received fewer dopaminergic drugs (-30% dosage in average). Motor improvement persisted to a lesser extent at 1 year(-39 +/- 31% 'off', -13 +/- 43% 'on'), partly because one patient stopped the treatment. Interestingly, the decrease in binding potentials (-4.0 +/- 10.5%) was slower than that expected in Parkinsonian patients (usually -10% per year) and was inversely correlated with Unified Parkinson's Disease Rating Scale-III improvement, r= 0.83 'off' and 0.91 'on'. CONCLUSION: This observational study emphasizes a potential effect of nicotine therapy on striatal dopamine transporter density, which may be interpreted as direct pharmacological effect or deceleration of neuronal loss.