High MET gene copy number predicted poorprognosis in primary intestinal diffuse large B-celllymphoma

In this retrospective study, we performed histology and chart reviews, immunohistochemistry and quantitative polymerase chain reaction for MET CN alterations on 28 surgically resected PI-DLBLs.There were 12 men and 16 women with a median age of 70 and a mean follow-up of 32 months. The median MET CN was 2.20 (range, 1.04 to 3.35). CN gain was observed in 11 cases, including 5 with CN greater than 3. Nine patients (32%) had diploid CN and eight (29%) with CN loss. Patients with gain or diploid CN showed significantly worse prognosis (P = 0.046) than those with CN loss. Furthermore, MET CN greater than 3 was associated with an adverse outcome (P = 0.003). Intestinal perforation at presentation was the sole clinicopathological factor associated with a poor prognosis (P = 0.004) and perforation was correlated with CN greater than 3 (P = 0.002).Our finding of MET CN gain as a poor prognostic factor in PI-DLBL patients might serve as the rationale for targeting MET signaling pathway in the treatment of these patients. Virtual slide The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1637072378895873