Objective assessment of blood and lymphatic vessel invasion and association with macrophage infiltration in cutaneous melanoma

Abstract

The aims of this study were to investigate the role of vascular invasion (blood and lymphatic), vessel density and the presence of tumour-associated macrophages as prognostic markers in 202 cutaneous melanoma patients. Sections of primary melanoma were stained with lymphatic-specific antibody D2-40 to assess lymphatic vessel invasion and density in intratumoural and peritumoural areas; an antibody against endothelial marker CD34 was used to determine blood vessel invasion and density, and an antibody against CD68 was used to determine macrophage counts. Immunohistochemically determined vascular invasion (combined blood and lymphatic) was compared with that determined using haematoxylin and eosin (H&E) staining. The use of immunohistochemistry increased detection of vascular invasion from 8–30% of patients, and histological exam of H&E-stained tissue was associated with a false positive rate of 64%. Lymphatic vessel invasion occurred at a much higher frequency than blood vessel invasion (27 and 4% of patients, respectively). Although immunohistochemically detected vessel invasion was significantly associated with histological markers of adverse prognosis, such as increased Breslow thickness, ulceration and mitotic rate (all P<0.001), no associations with relapse-free or overall survival were observed. High macrophage counts were significantly associated with markers of aggressive disease, such as Breslow thickness, ulceration and mitotic rate (P<0.001, P<0.001, P=0.005, respectively), and lymphatic vessel invasion and high microvessel density (P=0.002 and P=0.003, respectively). These results suggest that vascular invasion is more accurately detected using immunohistochemistry and occurs predominantly via lymphatic vessels. The association of vessel characteristics with histological characteristics of the primary melanoma provides evidence for their biological importance in melanoma, but that they were not associated with clinical outcome attests to the value of existing histological prognostic biomarkers. We note that a high macrophage count may be associated with neovascularisation and primary tumour growth, and may also promote invasion through lymphatic vessels.

Lymphangioinvasion in routine H&E staining is strongly associated with poor clinical outcome in lymph node-negative cutaneous melanoma patients

“…Furthermore, our results indicate that positive LYI status is related to poor outcome defined as shorter CSOS, DFS, as well as OS. Prognostic significance of LYI in the context of patient survival was demonstrated by several laboratories [3,6,28], while other groups did not confirm this observation [7,26,29].…”

“…Although definitive collective conclusions have yet not been drawn and considerable differences exist between various studies, a number of groups presented statistically significant associations between LYI status and key melanoma characteristics such as tumor thickness [3,25,26], ulceration [3,25,26], MR [25,26], or SLN [6,7,20,27]. The observed correlations give good reasons for further exploring LYI as a parameter of potential practical application.…”

Novel Identification of LYVE-1 Positive Macrophages in Rheumatoid Synovial Tissue

“…Monocytic/macrophage lineage cells have also been identified as the primary source of LECPs [10] and the presence of LECPs has been noted in a wide range of tumours where they play a role in tumour lymphangiogenesis [11]. Further to this, various studies now exist which show associations between macrophage populations and lymphatic vessel density and so support a role for macrophages as lymphangiogenic factors in cancers [12]. Furthermore, associations between CD68+ macrophage populations and metastatic lymph node cancers have also been observed [13].…”

Vascular invasion detected by orcein staining and its significance in different tumours, with emphasis on colorectal cancer

“…Tumour thickness is the most important histopathologic prognostic factor [51][52][53][54][55][56][57]. The studies on the significance of vascular invasion in melanoma came to different conclusions.…”

“…The studies on the significance of vascular invasion in melanoma came to different conclusions. Some reports suggest that vascular invasion is an independent prognostic factor [58][59][60], others hold the opposite view [55][56][57]. Vascular invasion can be detected on standard slides, however, immunohistochemistry to demonstrate endothelial cells might be useful.…”