[National guidelines of diagnosis and treatment of the non-Hodgkin lymphoma]. / Guías nacionales de diagnóstico y tratamiento de linfoma no Hodgkin.

Non-Hodgkin lymphoma comprises a heterogeneous group of haematological malignancies, classified according to their clinic, anatomic-pathological features and, lately, to their molecular biomarkers. Despite the therapeutic advances, nearly half of the patients will die because of this disease. The new diagnostic tools have been the cornerstone to design recent therapy targets, which must be included in the current treatment guidelines of this sort of neoplasms by means of clinical trials and evidence-based medicine. In the face of poor diagnoses devices in most of the Mexican hospitals, we recommend the present diagnose stratification, and treatment guidelines for non-Hodgkin lymphoma, based on evidence. They include the latest and most innovative therapeutic approaches, as well as specific recommendations for hospitals with limited framework and therapy resources.

Volume-of-interest assessment of oncologic response using 18F-FDG PET/CT: a phantom study.

UNLABELLED: The aim of this study was to evaluate the volume-of-interest (VOI) technique in the measurement of volume radioactivity and in the differentiation of necrotic sites from residual tumor activity in a phantom. METHODS: PET/CT was performed on a phantom filled with (18)F-FDG solution at different concentrations. The VOI was quantified in 2 sessions to evaluate the VOI measurements as a function of activity concentration in the phantom. Software was used to build the VOI, determine the volume radioactivity of the cylindric inserts (cm(3)), and compare them with their real volumes. The VOI technique was also used to discern the mixed distribution of regions of (18)F-FDG activity from cold regions that represent areas of necrosis without tumor activity. RESULTS: Volumes measured with the VOI technique were similar to the actual volumes of cylinders in the phantom (no statistical differences; P > 0.05 after t test analysis). The diameter of cold inserts correlated positively with the percentage of visualization (P < 0.01); in both sessions, it was possible to visualize 100% of the 12.7-, 11.1-, and 9.5-mm cold rods. CONCLUSION: VOI technique has shown great potential for evaluating volume radioactivity and differentiating hot and cold regions in a phantom; clinical studies should be performed with this technique to evaluate its utility.