Molecular Imaging in Inflammatory Bowel Disease.

Inflammatory bowel diseases (IBD) are chronic immune-mediated inflammatory diseases affecting the gastrointestinal tract. Classically, two subtypes of IBD are recognized: Ulcerative colitis and Crohn's disease. There is not a single and reliable test for IBD diagnosis but the nuclear medicine techniques like 99mTc-HMPAO autologous labelled leukocytes scintigraphy (WBCS) and PET/CT plays a role in the management of IBD. Leukocytes can be labelled "in vitro" (using 99mTc-HMPAO in Europe or 111In-oxine in America) or "in vivo" using antigranulocyte monoclonal antibodies. Nuclear medicine techniques are not the first choice to investigate IBD. Ultrasonography and magnetic resonance (radiation free) are probably the first option, and the diagnosis is commonly established by endoscopic biopsies. Nevertheless, WBCS is highly sensitive and accurate and represent a real option when other methods cannot used for whatever reason. In fact, a normal scan discards the presence of active IBD. The test is also useful to measure the extension and severity of the diseases and to evaluate the response to treatment. PET/CT imaging using 18F-FDG has recently been introduced and studied in both children and adults showing an excellent sensitivity for detecting active intestinal inflammation, but poor specificity in some studies. PET alone appears to be sufficient for the evaluation of ulcerative colitis, but PET/CT provides considerably more information than PET alone in the evaluation of Crohn's disease. Current clinical applications of PET in IBD include its use in the early evaluation of IBD, especially in children who may not tolerate an invasive test such as colonoscopy. Many questions remain to be answered, but PET appears to be a promising tool in the non-invasive evaluation of IBD. On the other hand, PET/MR could become in the near future a powerful tool in the evaluation of IBD patients. In addition, immuno-PET with antibodies targeting innate immune markers is also being investigated to detect colonic inflammation. The development of these technologies in humans could offer a less invasive method than endoscopy for the diagnosis and monitoring of IBD.

Lymphoscintigraphy in oral squamous cell carcinoma sentinel node biopsy and its role in the surgical planning.

AIM: The purpose of this study was to analyze the influence of different lymphatic pathways on surgical planning and the reliability of sentinel lymph node (SLN) biopsy to predict regional recurrence in patients with clinically N0 oral squamous cell carcinoma (OSCC). METHODS: Twenty-five patients with cT1/T2 N0 OSCC underwent a lymphoscintigraphy and an SLN biopsy. Elective neck dissection was performed at the validation stage and in patients with metastatic SLN. Scintigraphic and surgical SLN detection, pathologic status of SLN and of elective neck dissection, and regional recurrence in patients with negative SLN (pN0(sn)) were all analyzed. RESULTS: Scintigraphic and surgical detection were 96% and 100%, respectively, with 68% of negative SLN. Lymphoscintigraphy modified surgery in 32% of patients. In pN0(sn) patients, the free-of-disease survival rate was 88%. CONCLUSIONS: These results support the reliability of sentinel node biopsy in OSCC. Presurgical lymphoscintigraphy is essential, because it can modify the surgical procedure.

Characterization of radiologically indeterminate lung lesions: 99mTc-depreotide SPECT versus 18F-FDG PET.

AIM: To evaluate the diagnostic accuracy of 99m Tc-depreotide vs PET-18FDG scans in patients with suspicion of lung cancer. MATERIAL AND METHODS: Prospective study in 29 patients (age: 38-80 years) diagnosed of inderteminate lung lesions. Diagnosis was established by histology based on samples of surgical resection, fine needle aspiration (FNA) or broncoalveolar lavage (BAL). Within a maximum of 10 days, without pre-established fixed order the following exams were performed: 1) Whole body and chest SPECT-CT with Tc-depreótide (DEP-SPECT) and 2) PET-CT study with F-FDG (PET-FDG). Every exam was evaluated by Nuclear Medicine especialist blinded to patient data. RESULT: Malignancy was confirmed in 20 patients. PET-FDG was positive in all cases. DEP-SPECT was positive in 17 and falselly negative in 3, one carcinoid tumor, one undifferentiated non-small cell adenocarcinoma, and a moderately differentiated adenocarcinoma. In the remaining 9 patients benignancy was confirmed; both studies were normal in 8 and falselly positive in one case of non-specific inflammatory lung process. In 9 out of the 20 cases with malignancy extrapulmonar uptake was seen, with a total number of 19 lesions. In two cases the extrapulmonar uptake were non ganglionar metastasis (bone and adrenal) and in 7 due to mediastinic ganglionar involvement. ROC analysis using peak SUV FDG (cut-off point of 3.5) uptake and target/background depreotide uptake (cut-off point of 1.3) provided, sensitivity and specificity values of 95% and 89% of 84% and 88% for PET and SPECT respectively. It does not exist statistically significant differences between both methods (Z-test SPSS). In summary, FDG-PET has a greater sensitivity and diagnostic accuracy for assessing malignancy of indeterminate lung lesions, and for detection of extrapulmonary involvement, DEP-SPECT represents a good diagnostic alternative for centers where PET is not available.

[Cost-effectiveness analysis of samario-153 (Quadramet) for the treatment of patients with prostate cancer and bone metastases]. / Análisis coste-efectividad de samario-153 (Quadramet) en el tratamiento del dolor en pacientes con cáncer de próstata y metástasis óseas.

OBJECTIVE: To evaluate the cost-effectiveness of samarium [153Sm-EDTMP] (Quadramet) compared to conventional therapy in the treatment of pain in patients with prostate cancer and bone metastases. METHOD: A decision tree model for the treatment of bone pain due to metastases was adapted to the Spanish context. The model represents the standard treatment patterns in Spain for the study population. The time-course of the model is 4 months and it computes an estimate for the cost of pain control per patient. The effectiveness data for the model derive from a randomised trial. The current treatment patterns have been established according to the consensus opinions of a group of medical experts. RESULTS: The cost of pain control per patient is euro 12,515.39 for conventional therapy and euro 5,595.52 for samarium-153 (Quadramet) therapy. The incremental cost-effectiveness analysis shows that samarium-153 (Quadramet) is a dominant therapy. It presents lower costs and higher efficacy than the conventional strategy. The sensitivity analyses showed these results to be robust. CONCLUSION: Samarium-153 (Quadramet) is cost-effective in treating pain in patients with prostate cancer and bone metastases.

Análisis coste-efectividad de samario-153 (Quadramet®) en el tratamiento del dolor en pacientes con cáncer de próstata y metástasis óseas / Cost-effectiveness analysis of samario-153 (Quadramet®) for the treatment of patients with prostate cancer and bone metastases

Objetivo. Realizar un análisis coste-efectividad de samario [153Sm-EDTMP] (Quadramet®) respecto a la terapia convencional, para el tratamiento del dolor causado por metástasis óseas en pacientes con cáncer de próstata. Metodología. Se ha adaptado un modelo de árbol de decisión, que representa el tratamiento del dolor óseo metastásico, al contexto español. El modelo muestra las opciones terapéuticas habituales en el contexto sanitario español para la población del estudio. El horizonte temporal del modelo es de 4 meses y calcula el cociente coste-efectividad por paciente controlado. Los datos de eficacia del modelo provienen de un ensayo clínico aleatorizado. Las pautas de tratamiento habituales en España han sido indicadas por varios especialistas médicos. Resultados. El coste por paciente controlado para la terapia convencional es de 12.515,39 € y para la terapia con samario-153 (Quadramet®) es de 5.595,52 €. El análisis coste-efectividad incremental muestra que samario-153 (Quadramet®) es una terapia dominante, es decir, que presenta una mayor eficacia y un menor coste que la terapia convencional. Los resultados obtenidos han demostrado ser robustos en un extenso análisis de sensibilidad. Conclusiones. La terapia con samario-153 (Quadramet®) es eficiente en el tratamiento del dolor de pacientes con cáncer de próstata y metástasis óseas

Objective. To evaluate the cost-effectiveness of samarium [153Sm-EDTMP] (Quadramet®) compared to conventional therapy in the treatment of pain in patients with prostate cancer and bone metastases. Method. A decision tree model for the treatment of bone pain due to metastases was adapted to the Spanish context. The model represents the standard treatment patterns in Spain for the study population. The time-course of the model is 4 months and it computes an estimate for the cost of pain control per patient. The effectiveness data for the model derive from a randomised trial. The current treatment patterns have been established according to the consensus opinions of a group of medical experts. Results. The cost of pain control per patient is €12,515.39 for conventional therapy and € 5,595.52 for samarium-153 (Quadramet®) therapy. The incremental cost-effectiveness analysis shows that samarium-153 (Quadramet®) is a dominant therapy. It presents lower costs and higher efficacy than the conventional strategy. The sensitivity analyses showed these results to be robust. Conclusion. Samarium-153 (Quadramet®) is cost-effective in treating pain in patients with prostate cancer and bone metastases