Objective To determine whether the Gyrus ACMI plasma kinetic bipolar device (Gyrus ACMI, Southborough, MA) improves pathologic specimen preservation and clinical outcomes compared to standard monopolar electrocautery. Patients and methods In our prospective study, 83 patients underwent monopolar or bipolar transurethral resection of bladder tumors between April 2006 and February 2007 at Memorial Sloan-Kettering Cancer Center. Dedicated genitourinary oncology pathologists blinded to resection type and assessed pathologic features including stage and grade, presence of muscularis propria, fragment size, presence and thickness of thermal artifacts within the specimen, layer of tissue most affected, severity of tissue distortion, and diagnostic impact of thermal artifacts. Clinical outcomes including, perforation, obturator reflex, need for muscle paralysis, a catheter, or admission, were recorded. Clinical and pathologic outcomes between resection modality were compared. Results There were no significant thermal artifacts in 9/38 (23.7 %) and 11/45 (24.4 %) monopolar and bipolar specimens, respectively. The layer of bladder tissue most affected by thermal artifacts was readable in 18/38 (47.4 %) monopolar and 27/45 (60.0 %) bipolar specimens. Tissue distortion from thermal artifacts led to areas within 11/38 (28.9 %) monopolar and 7/45 (15.6 %) bipolar specimens being unreadable. Ultimately, thermal artifacts caused moderate diagnostic difficulty in 2/38 (5.3 %) specimens of the monopolar group and severe diagnostic difficulty in 1/45 (2.2 %) bipolar specimens. Clinically, there was no major difference between resection methods. Conclusion Plasma kinetic bipolar equipment appears to cause less tissue distortion and has the potential to facilitate staging and grading of bladder tumors. No differences in clinical outcomes were appreciated between resection methods. If these results can be repeated in larger studies, the bipolar device represents a small advancement in transurethral resection.

Cancer identified in transition zone directed needle biopsy cores was not from the transition zone or did not reflect a dominant transition zone lesion in almost 80% of cases. Cancer identified in a left or right transition zone directed needle biopsy did not predict ipsilateral transition zone cancer in almost 50% of cases. These findings suggest that such biopsies do not adequately characterize transition zone tumors. Thus, care should be taken in their interpretation.

Context.—Diffuse large B-cell lymphoma (DLBCL) can be assigned to prognostic subgroups, including germinal center B-cell (GCB) and activated B-cell subgroups, by using gene expression profiling and, reportedly, immunohistochemistry for CD10, Bcl-6, and multiple myeloma-1/interferon regulatory factor-4 (MUM1/IRF4). Objective.—To compare 2 commercial MUM1/IRF4 antibody formulations for accuracy in subtyping DLBCL against gene expression profiling, compare subtyping to patient survival, and evaluate the usefulness of GCB and non-GCB subtyping in relapsed and transformed DLBCL. Design.—Evaluation of 2 commercial MUM1/IRF4 antibodies, ICSTAT/M17 and Mum-1p, by using 40 cases of de novo, relapsed, and transformed DLBCL; and comparison of the results obtained with gene expression profiling and survival. Results.—Immunohistochemistry predicted the gene expression profiling subtype 71.8% and 69.2% of the time overall with use of the Mum-1p and ICSTAT/M17 antibodies, respectively, and 100% and 91.7% of the time when MUM1/IRF4 expression determined subtype. Gene expression profiling and immunohistochemistry revealed nearly identical 5-year overall survival rates for the GCB vs non-GCB subtypes (68.0% for GCB vs 24.7% for non-GCB with use of gene expression profiling [P = .03] and 70.2% vs 18.4%, respectively, with use of immunohistochemistry [P < .001]). When de novo, transformed, and relapsed cases were analyzed separately, 5-year overall survival rates were also significantly different. Conclusions.—Immunohistochemistry can be used to subclassify DLBCL, including a very small series of transformed and relapsed cases, into GCB and non-GCB subtypes and predict survival rates similar to those predicted by use of gene expression profiling. The 2 MUM1/IRF4 antibodies performed similarly.

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