BACKGROUND Fluorine‐18 fluoro‐deoxyglucose positron emission tomography (FDG‐PET) scanning has excellent sensitivity and specificity for staging non‐Hodgkin lymphomas, but to the authors' knowledge few studies to date have evaluated FDG‐PET in low‐grade lymphomas only. METHODS A retrospective study was performed on patients with biopsy‐proven nontransformed and transformed follicular lymphoma (FL), B‐cell small‐cell lymphocytic lymphoma (SLL/CLL), or marginal zone lymphoma (MZL) who underwent PET and computed tomography (CT) scans within 3 weeks. Standard uptake values (SUV) of all abnormal foci were measured. RESULTS In FL, PET demonstrated 94% sensitivity and 100% specificity for staging. PET was more specific than CT for detecting recurrence or assessing therapeutic responses (91% vs. 50%). FDG avidity among patients with WHO Grades 1, 2, and 3 disease was not significantly different (analysis of variance [ANOVA]). For MZL staging, PET had moderate sensitivity (71%) and outperformed CT alone in the depiction of extranodal sites (85% vs. 57% sensitivity). In SLL/CLL, PET sensitivity was 53% and underestimated disease extent in 5 of 19 patients (26%) compared with CT. PET did not affect initial management but confirmed suspected recurrences in 75% of patients. Nontransformed FL had a higher SUV (ANOVA, P<.05) compared with MZL and SLL/CLL. SUV was higher in transformed than in nontransformed tumors (P<.001, Student t test). CONCLUSIONS PET usefulness in staging low‐grade lymphomas varies depending on histology. PET sensitivity is excellent in FL and moderate in MZL. PET is more specific than CT for follow‐up in all types. PET has limited usefulness for SLL/CLL staging. However, a suggestive pattern of hazy and mild uptake was often noted in positive scans. In all low‐grade lymphomas, the emergence of foci of intense uptake should raise suspicion of conversion to high‐grade disease. Cancer 2006. © 2006 American Cancer Society.

The use of abduction and external rotation in shoulder MR arthrography can be a helpful tool that complements sequences that use conventional positions for characterizing a variety of abnormal conditions in the shoulder.

Although rare, the posterior synovial fold can be recognized and should not be confused with a posterior labral tear. Further investigation is needed to assess its histologic properties and its clinical significance.

We provide a functional characterization of transcription factor NF-κB in protists and provide information about the evolution and diversification of this biologically important protein. We characterized NF-κB in two protists using phylogenetic, cellular, and biochemical techniques. NF-κB of the holozoan Capsaspora owczarzaki (Co) has an N-terminal DNA-binding domain and a C-terminal Ankyrin repeat (ANK) domain, and its DNA-binding specificity is more similar to metazoan NF-κB proteins than to Rel proteins. Removal of the ANK domain allows Co-NF-κB to enter the nucleus, bind DNA, and activate transcription. However, C-terminal processing of Co-NF-κB is not induced by IκB kinases in human cells. Overexpressed Co-NF-κB localizes to the cytoplasm in Co cells. Co-NF-κB mRNA and DNA-binding levels differ across three Capsaspora life stages. RNA-sequencing and GO analyses identify possible gene targets of Co-NF-κB. Three NF-κB-like proteins from the choanoflagellate Acanthoeca spectabilis (As) contain conserved Rel Homology domain sequences, but lack C-terminal ANK repeats. All three As-NF-κB proteins constitutively enter the nucleus of cells, but differ in their DNA-binding abilities, transcriptional activation activities, and dimerization properties. These results provide a basis for understanding the evolutionary origins of this key transcription factor and could have implications for the origins of regulated immunity in higher taxa.