A META-ANALYSIS OF THE RELATIONSHIP BETWEEN LYMPHATIC MICROVESSEL DENSITY AND THE SURVIVAL OF PATIENT WITH COLORECTAL CANCER

Abstract

Colorectal cancer (CRC) is a frequentlyobserved malignant neoplasm that is a leadingcause of cancer death despite recent advancesin treatment and research. The role oflymphangiogenesis in CRC development is asource of controversy in current research.We undertook this study to examine therelationship between lymphatic microvesseldensity (LMVD) and the overall survival (OS)or disease free survival (DFS) of CRC usingmeta-analysis of recent studies. PubMed andEmbase databeases were searched and ninerelevant studies including 799 total patientswere included. Six studies including 575patients focused on overall survival (OS) and3 studies with 224 patients focused on diseasefree survival (DFS). We performed a metaanalysisto estimate the prognostic role oflymphatic microvessel density by combiningseparately estimated hazard ratios. Aremarkable correlation between LMVD andDFS was observed in pooled analyses using afixed-effect model (HR 2.29; 95% CI 1.11,3.48). LMVD and OS showed a pooled HRvalue of 1.02 (95% CI 0.71,1.33), indicating nosignificant correlation between LMVD andOS. There was no evidence for significantheterogeneity or publishing bias in both DFSand OS (I2=0.0%, P=0.861; I2 =48.1%,P=0.086, respectively). A close relationshipwas observed between LMVD and DFS, though no correlation between LMVD andOS was apparent. The current meta-analysissuggests that LMVD may be a poor prognosticfactor for CRC patients. However, theseresults should be regarded cautiously andfuture confirmatory studies are necessary.