Non-hodgkin lymphomas presenting as soft tissue masses: A single center experience and meta-analysis of the published series

Background: Lymphomas with involvement of soft tissues as a primary event are very rare. The published studies have a small sample size, most of them being reported as case reports. Patients and Methods: In this article we describe our experience with soft tissue non-Hodgkin lymphomas (NHL) diagnosed and treated in our institution over a 15-year period. Moreover, we systematically review the available data from the literature in the past 2 decades, considering all the published series and case reports available from 1990 to 2011 using a PubMed access. Results: In the monocentric analysis, 16 consecutive patients treated at our Institution from 1996 to 2011 were considered. In the literature search, we selected 16 case reports (18 patients) and 5 case series (49 patients), including a total of 67 patients. Eighty-three patients were finally considered in the combined analysis. The most common histologic subtype was diffuse large B cell lymphoma (DLBCL) (>50% of cases in both groups). In both analyses we observed an inferior outcome for DLBCL compared with indolent B-cell NHL (5-year progression free survival: 34% vs. 64%, respectively, in the combined analysis; P =.01). Furthermore, the prognosis in the DLBCL group appears to be worse compared with the historical data of DLBCL patients treated with chemoimmunotherapy. Conclusions: Though indolent soft tissue B-cell NHLs appear to have a good outcome, soft tissue DLBCLs represent an anatomic-clinical entity with aggressive features, and dismal prognosis. Strategies of first-line therapy intensification could be considered. Studies aiming to a better biologic characterization of this peculiar entity are warranted.