Predictive value of 18F-FDG PET/CT on survival in locally advanced rectal cancer after neoadjuvant chemoradiation.

OBJECTIVE: To evaluate the prognostic value of 18F-FDG PET/CT in terms of survival in patients with locally advanced rectal cancer (LARC) who had undergone surgery preceded by neoadjuvant chemoradiotherapy (nCRT). Moreover, the existence of correlation between Overall Survival (OS) and Disease Free Survival (DFS) with pathological staging ((y)pTNM and TRG) was evaluated. PATIENTS AND METHODS: A total of 58 patients with biopsy-proven of LARC were included. All patients underwent conventional diagnostic/staging procedures to characterize the rectal lesion. The first whole-body 18F-FDG PET/CT was performed 1 week before the beginning of nCRT (baseline scan). The second 18F-FDG PET/CT was scheduled at 5-6 weeks from nCRT completion (post-nCRT scan). Survival was evaluated in 3 different restaging classification systems, based on focusing only on primary lesion (TRG), loco-regional evaluation (ypTNM) and whole-body 18F-FDG PET/CT evaluation (VRA). RESULTS: Among the 58 patients at the end of the observation, 46/58 patients (79.3%) were alive and 12/58 (20.7%) were dead. This work demonstrated a higher percentage of patients with TRG complete response (39.7%) compared to literature (24.6%), with longer Overall Survival (OS) and Disease Free Survival (DFS) in responders even if without statistically significant differences. CONCLUSIONS: The present study highlights the predictive and prognostic potential role of 18F-FDG PET/CT in assisting physicians on personalized decision in the selective risk-adapted treatment strategy, and to schedule the correct follow-up approach.

99mTc-diphosphonates bone scintigraphy for vitality evaluation in cleft palate.

Cleft of the lip, palate and alveolus are congenital oro-maxillofacial malformation with an established treatment protocol. At present, there is great interest in the alveolar bone grafting procedures that involve the use of platelet-rich-plasma (PRP), to enhance bone formation and specifically to promote bone graft healing in head and neck tissues regeneration. The aim of this retrospective case report study was to assess the condition and viability of the standard bone grafting in association with PRP (platelet rich plasma) to enhance osteogenesis and maintain osteointegration in alveolar cleft with a follow up of eight years from the surgical procedure. The viability of bone grafts was documented by means of head bone scintigraphy (99mTc-MDP). The scintigrams revealed the decreased uptake at the cleft region and the increased uptake at the adjacent alveolus of the cleft. From these findings we suggest that platelet concentrates decrease the need of further surgical intervention in cleft palate patients. In addition, scintigraphy may be useful to evaluate postoperative bone formation in the alveolar cleft.

Smoking in Patients with Parkinson's Disease: preliminary striatal DaT-SPECT findings.

OBJECTIVE: To assess whether cigarette smoking interferes with dopaminergic transmission in current- and never-smoking patients with Parkinson's disease. MATERIALS AND METHODS: Striatal [123I]FP-CIT single photon emission computed tomography was performed in 67 patients with Parkinson's disease (35 women and 32 men aging 60.8 ± 10.1 years and staging 1.76 ± 0.5 on the Hoehn and Yahr scale). At study time, there were 13 current-smokers and 54 never-smokers. RESULTS: Current-smokers showed a significantly lower putamen/occipital [123I]FP-CIT ratio and a non-significant trend to a lower caudate/occipital [123I]FP-CIT ratio uptake. Current-smokers were also characterized by a lower off UPDRS-III motor score. A logistic regression analysis adjusted for age, sex, disease duration, Hoehn and Yahr staging, and medication indicated a significant lower [123I]FP-CIT uptake not only in the putamen (odds ratio, 0.1; 95% confidence interval, 0.01 to 0.65; P = 0.02) but also in the caudate (odds ratio, 0.2; 95% confidence interval, 0.04 to 0.71; P = 0.015) as well as a lower UPDRS-III motor score (odds ratio, 0.9; 95% confidence interval, 0.81 to 0.99; P = 0.04) in current-smokers. CONCLUSIONS: The lower [123I]FP-CIT uptake together with the lower UPDRS-III motor score observed in our current-smokers patients with Parkinson's disease (even taking into account variables that are probably expression of dopaminergic neuron decline and treatment) would support an effect of smoking on dopaminergic synaptic mechanisms.

Role of 18F-FDG PET/CT in diagnosing peritoneal carcinomatosis in the restaging of patient with ovarian cancer as compared to contrast enhanced CT and tumor marker Ca-125 / Papel del 18F-FDG PET/CT en el diagnóstico de carcinomatosis peritoneal en la reclasificación de los pacientes con cáncer de ovario en comparación con el TC con contraste y con el marcador tumoral Ca-125

Objectives. To investigate the role of whole-body fluorine-18-2-deoxy-2-fluoro- d -glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in the identification of peritoneal carcinomatosis in patients with ovarian cancer (OC). Material and methods. Seventy-nine patients with histologically proven stages III-IV OC who underwent 18F-FDG PET/CT were studied retrospectively. We considered group A as 51 patients who also underwent computed-tomography with contrast-enhancement (CECT), and group B as 35 patients who had also been tested for biomarker Ca-125. Sensitivity, specificity, accuracy, positive predictive values (PPV) and negative predictive values (NPV) of 18F-FDG PET/CT as compared to CECT and to Ca-125 were evaluated. Results. 18F-FDG PET/CT’ sensitivity, specificity, accuracy, PPV and NPV for all 79 patients were: 85%, 92.31%, 88.61%, 91.89% and 85.71%, respectively. 18F-FDG PET/CT sensitivity in group A was 78.6%, while it was 53.6% for CECT. 18F-FDG PET/CT specificity, calculated in the same group, was 91.3%, while that of CECT was 60.9% (statistically significant difference, McNemar 4, P = 0.039). Accuracy was 84.3% and 56.9%, respectively. 18F-FDG PET/CT’ sensitivity in group B was 86.4%, while that of Ca-125 was 81.8% (no statistical difference, McNemar 0, P = 1). 18F-FDG PET/CT specificity in group B was 84.6% while that of Ca-125 was 38.5% (clear but not statistically significant difference, McNemar 3.12, P = 0.070). Accuracy calculated in the same group was 85.7% for 18F-FDG PET/CT and 65.7% for Ca-125. Conclusion. 18F-FDG PET/CT is a useful diagnostic tool when peritoneal biopsy cannot be performed and it can better select those who are candidates for adjuvant chemotherapy (AU)

Objetivos. Investigar el papel de flúor-18-2-desoxi-2-fluoro-D-glucosa tomografía por emisión de positrones/tomografía computarizada (18F-FDG PET/CT) en la identificación de la carcinomatosis peritoneal en pacientes con cáncer de ovario (CO). Material y métodos. Setenta y nueva pacientes con CO en estadio III-IV que se sometieron a 18F-FDG PET/CT fueron estudiadas retrospectivamente. Consideramos el grupo A de 51 pacientes que también realizaron la tomografía computarizada con contraste (CECT) y el grupo B de 35 pacientes que tenían cuantificación del Ca-125. Se evaluó sensibilidad, especificidad, exactitud, valor predictivo positivo (VPP) y valores predictivos negativos (VPN) de 18F-FDG PET/CT en comparación con CECT y Ca-125.Resultados. La sensibilidad, especificidad, exactitud, VPP y VPN de 18F-FDG PET/CT en los 79 pacientes fueron: 85, 92,31, 88,61, 91,89 y 85,71% respectivamente. La sensibilidad de 18F-FDG PET/CT en el grupo A fue de 78,6% y de 53,6% por CECT. La especificidad de 18F-FDG PET/CT en el mismo grupo fue de 91,3%, mientras la de CECT del 60,9% (diferencia estadísticamente significativa, McNemar = 4, P = 0,039); la exactitud fue respectivamente de 84,3 y 56,9%. La sensibilidad de la 18F-FDG PET/CT en el grupo B fue de 86,4%, mientras que la del Ca-125 fue de 81,8% (sin diferencia estadística, McNemar = 0, P = 1). La especificidad 18F-FDG PET/CT en el grupo B fue de 84,6%, mientras que la del Ca-125 fue de 38,5% (diferencia evidente, no estadísticamente significativa, McNemar = 3,12, P = 0,070). La exactitud en el mismo grupo fue 85,7% para el 18F-FDG PET/CT y 65,7% para Ca-125. Conclusión. La 18F-FDG PET/CT es un instrumento de diagnóstico útil cuando la biopsia peritoneal no se puede realizar y puede seleccionar de manera mejor las candidatas a quimioterapia adyuvante (AU)

Radio-guided sentinel lymph node identification by lymphoscintigraphy fused with an anatomical vector profile: clinical applications.

OBJECTIVE: To develop a method to fuse lymphoscintigraphic images with an adaptable anatomical vector profile and to evaluate its role in the clinical practice. METHODS: We used Adobe Illustrator CS6 to create different vector profiles, we fused those profiles, using Adobe Photoshop CS6, with lymphoscintigraphic images of the patient. We processed 197 lymphoscintigraphies performed in patients with cutaneous melanomas, breast cancer or delayed lymph drainage. RESULTS: Our models can be adapted to every patient attitude or position and contain different levels of anatomical details ranging from external body profiles to the internal anatomical structures like bones, muscles, vessels, and lymph nodes. If needed, more new anatomical details can be added and embedded in the profile without redrawing them, saving a lot of time. Details can also be easily hidden, allowing the physician to view only relevant information and structures. Fusion times are about 85 s. The diagnostic confidence of the observers increased significantly. The validation process showed a slight shift (mean 4.9 mm). CONCLUSIONS: We have created a new, practical, inexpensive digital technique based on commercial software for fusing lymphoscintigraphic images with built-in anatomical reference profiles. It is easily reproducible and does not alter the original scintigraphic image. Our method allows a more meaningful interpretation of lymphoscintigraphies, an easier recognition of the anatomical site and better lymph node dissection planning.

Whole-body MR-DWIBS vs. [18F]-FDG-PET/CT in the study of malignant tumors: a retrospective study.

PURPOSE: Our aim was to assess the overall diagnostic accuracy of magnetic resonance diffusion-weighted whole-body imaging with background signal suppression (MR-DWIBS) compared with ([(18)F]-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT), considered the reference standard of whole-body tumour imaging modalities, in a series of consecutive patients with malignant tumour. MATERIALS AND METHODS: Thirty-eight patients diagnosed with a malignant tumour over a 4-month period were enrolled in this retrospective, observational study. PET/CT and MR-DWIBS images were reviewed in double-blind manner by a nuclear medicine physician and radiologists with 4 years experience. Lesion size, standard uptake value (SUV) and apparent diffusion coefficient (ADC) were measured and calculated for each lesion. RESULTS: The qualitative analysis of MR-DWIBS and [(18)F]-FDG-PET/CT showed that two patients were negative at both techniques. MR-DWIBS was positive in 36 patients, 34 of whom were positive and two negative at [(18)F]-FDG-PET/CT, respectively. Two hundred and fifty-five lesions were identified by MR-DWIBS and 184 by [(18)F]-FDG-PET/CT, which was a significative discordance. Correlation between SUV and ADC of lesions positive at both techniques was not statistically significant. The mean difference between lesion size in [(18)F]-FDG-PET/CT and MR-DWIBS was not statistically significant. No correlation was found between glucose metabolism and water motion. CONCLUSIONS: MR-DWIBS may be used to evaluate localisation of parenchymal neoplasms but is less efficacious in characterising lymph-node and skeletal lesions. [(18)F]-FDG-PET/CT remains the best whole-body technique to identify lymph-node and skeletal lesions, but its limitation is identifying tumours with low glucose metabolism as in mucinous neoplasms. MR-DWIBS evaluation must be integrated with morphological images to increase MR diagnostic accuracy.

Acute pulmonary embolism: comparison and integration of perfusion lung scintigraphy with multislice spiral CT.

PURPOSE: This study compared and integrated the data from perfusion lung scintigraphy and multislice computed tomography (CT) for the emergency diagnosis of acute pulmonary embolism in nuclear medicine and radiology departments operating around the clock. MATERIALS AND METHODS: One hundred and seven patients with a clinical and laboratory suspicion of acute pulmonary embolism who had already undergone chest radiography were divided into four groups according to the time interval between onset of clinical suspicion and performance of the two diagnostic examinations (0-24 h, 24-48 h, 0-48 h, 2-7 days). Cohen's test for the analysis of statistical concordance was used. RESULTS: Perfusion lung scintigraphy and multislice CT were positive in 29/107 (27.1%) and negative in 78/107 (72.89%). Positive concordance (PC) was found in 22 cases and negative concordance (NC) in 71 cases: 0-24 h: PC in 12, NC in 32 cases; 24-48 h: PC in 3, NC in 15 cases; 0-48 h: PC in 15, NC in 47 cases; 2-7 days: PC in 7, NC in 24 cases. CONCLUSIONS: Perfusion lung scintigraphy and multislice CT demonstrated elevated concordance if performed within 7 days of the onset of suspicion of acute pulmonary embolism. Concordance was higher if the examinations were completed within 24-48 h. In suspected acute pulmonary embolism, it is mandatory to reach a correct diagnosis within few hours--48 at the most.

A simple method for correcting overestimated glomerular filtration rate in obese subjects evaluated by the Cockcroft and Gault formula: a comparison with 51Cr EDTA clearance.

AIM: The Cockcroft and Gault formula is a quick and reliable method for calculating creatinine clearance without a 24-hour urine collection (CG-cl). In obese subjects an excess of fat mass provokes a reduction in daily creatinine urine excretion per body kilo weight and is responsible for overestimated renal function when calculated by CG-cl. The aim of this study was to devise a simple correction method which could also make use of CG-cl in obese subjects. PATIENTS AND METHODS: In 52 subjects with a body mass index (BMI) > 25, renal function was assessed by simultaneously determining creatinine clearance using 24-hour urine collection (Cr-cl) and the CG-cl. The percentage difference between the 2 clearances (delta %) was correlated with BMI for each patient using simple linear regression analysis. The estimated regression model (delta% = 1.217 BMI-- 24.81) provided the following CG-cl correction formula for obese subjects: Corrected CG-cl = CG-cl (1.25 - 0.012 BMI). Its validity was evaluated in another group of 20 subjects with BMI > 25 by comparing the results obtained with Corrected CG-cl to those obtained by CG-cl and MDRD formula (MDRD-cl) using the clearance of 51Cr-EDTA (5 Cr-EDTA-cl) as the GFR measurement gold standard. RESULTS AND CONCLUSION: Linear regression analysis of CG-cl, MDRD-cl and Corrected CG-cl compared to 5tCr-EDTA-cl (considered as the independent variable) resulted in the following determination coefficients (R2): 0.687; 0.818; 0.947, respectively. In conclusion, this formula can be considered a quick and reliable method for CG-cl correction in obese subjects.