A pioneer in the research areas of angiogenesis and the biology and pathology of cutaneous melanoma for nearly three decades, Dr. Raymond Barnhill’s primary research interest is the relationship between angiogenesis and tumor progression in melanocytic lesions, and the mechanisms of melanoma metastasis via extravascular migration of tumor cells. He is also investigating and analyzing the clinical, epidemiological and histopathological characteristics of precursor lesions to melanoma, including dysplastic nevi, unusual melanocytic lesions (such as Spitz tumors), blue nevi, and unusual and borderline melanocytic lesions and melanomas.
More recently, in the past ten years he has focused, with Dr. Claire Lugassy, on drawing attention to angiotropism (the tumor cells closely opposed to the external surfaces of vessels) as a meaningful biologic process and correlate of Extravascular Migratory Metastasis (EVMM), and as a prognostic factor in primary melanoma. He co-developed EVMM as an important alternative mechanism of melanoma metastasis distinct from intravascular dissemination. During the process of EVMM along vessels, angiotropic melanoma cells migrate along the external, abluminal surfaces of vascular channels in a pericytic location without intravasation. His studies with Lugassy also developed in vitro and in vivo models to demonstrate the migration of melanoma cells and other types of tumor, in particular glioblastoma, along the external surfaces of vessels in a pericytic location.
In their most recent work, Barnhill and Lugassy have selected, from a microarray analysis involving angiotropic melanomas, several genes that are linked to neural crest migration and, potentially, these genes may also directly be involved in EVMM. They have also emphasized the analogies of EVMM with neural crest cell migration and vasculogenesis/angiogenesis. He continues to investigate these processes, and angiotropism and EVMM are now recognized by the international scientific community as an important alternative means of melanoma and other tumor dissemination, and as a key focus of present and future cancer research.
Selected Cancer-Related Publications:
Lugassy C, Lazar V, Dessen P, van den Oord JJ, Winnepenninckx V, Spatz A, Bagot M, Bensussan A, Janin A, Eggermont AM, Barnhill RL. Gene expression profiling of human angiotropic primary melanoma: selection of 15 differentially expressed genes potentially involved in extravascular migratory metastasis. Eur J Cancer. 2011 May;47(8):1267-75. Epub 2011 Feb 19.
Barnhill RL, Kutzner H, Schmidt B, Ali L, Bagot M, Janin A, Lugassy C. Atypical spitzoid melanocytic neoplasms with angiotropism: a potential mechanism of locoregional involvement. Am J Dermatopathol. 2011 May;33(3):236-43.
Barnhill RL, Busam KJ, From L, Bagot M, Lugassy C, Berwick M. Inter-observer concordance for the recognition of angiotropism in human melanoma. Pigment Cell Melanoma Res. 2011 Jun;24(3):582-3. doi: 10.1111/j.1755-148X.2011.00854.x. Epub 2011 Apr 28.
Lugassy C, Barnhill RL. Angiotropic malignant melanoma and extravascular migratory metastasis in melanoma: From concept to gene expression: A review. Expert Rev Dermatol 2011;6:303-316.
Broekaert SM, Roy R, Okamoto I, van den Oord J, Bauer J, Garbe C, Barnhill RL, Busam KJ, Cochran AJ, Cook MG, Elder DE, McCarthy SW, Mihm MC, Schadendorf D, Scolyer RA, Spatz A, Bastian BC. Genetic and morphologic features for melanoma classification. Pigment Cell Melanoma Res. 2010 Dec;23(6):763-70.