Tumour vascularity is not a prognostic factor for cutaneous melanoma

Vessel co-option and angiotropic extravascular migratory metastasis: a continuum of tumour growth and spread?

Two fields of cancer research have emerged dealing with the biology of tumour cells localised to the abluminal vascular surface: vessel co-option (VCo), a non-angiogenic mode of tumour growth and angiotropic extravascular migratory metastasis (EVMM), a non-hematogenous mode of tumour migration and metastasis. VCo is a mechanism by which tumour cells gain access to a blood supply by spreading along existing blood vessels in order to grow locally. Angiotropic EVMM involves "pericytic mimicry" (PM), which is characterised by tumour cells continuously migrating in the place of pericytes distantly along abluminal vascular surfaces. When cancer cells are engaged in PM and EVMM, they migrate along blood vessels beyond the advancing front of the tumour to secondary sites with the formation of regional and distant metastases. In the present perspective, the authors review the current scientific literature, emphasising the analogies between embryogenesis and cancer progression, the re-activation of embryonic signals by "cancer stem cells", and the important role of laminins and epithelial-mesenchymal-transition. This perspective maintains that VCo and angiotropic EVMM constitute complementary processes and represent a continuum of cancer progression from the primary tumour to metastases and of tumour growth to EVMM, analogous to the embryonic development program.

Immunophenotypic Differences in Tumor-Infiltrating Lymphocytes and Neovascularization Between Primary Cutaneous Melanoma With and Without Metastasis: An Immunohistochemical Study of 80 Cases

ABSTRACT

The prognostic implications of the immunophenotype of the tumor-infiltrating lymphocytes (TILs) in primary cutaneous melanoma are well known. In recent years, the study of this immunophenotype has also resulted in immunotherapeutic consequences. The aims of this study were to characterize the subpopulations of TILs in primary cutaneous melanoma, in cases with and without metastasis, as well as the neovascularization associated with the primary neoplasm, and its influence on the development of metastasis. To this end, the immunophenotype of TILs and the neovascularization of 80 patients with primary cutaneous melanoma (40 each with metastatic and non-metastatic melanoma) were analyzed by immunohistochemistry for CD3, CD4, CD8, FOXP3, PD-1, CD31, and D2-40 antibodies. We found that higher frequencies of TILs with brisk pattern, and CD4+, CD8+, and CD20+ cells in TILs, and a lower frequency of CD31+ vessels were histopathological features associated with better prognosis in primary cutaneous melanoma. Our results support the notion that the immunohistochemical study of TILs and neovascularization in primary cutaneous melanoma may be helpful tools for identifying patients at increased risk of metastasis development.

Comparison of orosomucoid-1 immunoexpression and angiogenesis between oral squamous cell carcinoma cases with different histological grades

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most common malignancy in this region, and thus, further elucidation of its tumoral mechanisms is important. One of the main roles of the acute-phase protein orosomucoid-1 (ORM1) is the promotion of angiogenesis, which is key for tumor nutrition and growth.

AIM

Our aim was to evaluate the immunohistochemical expression of ORM1 and the angiogenic activity indicated by microvascular density (MVD) in OSCC samples according to histological grade.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded sections from 45 OSCC cases were submitted to immunohistochemistry: 25 were well-differentiated OSCC, 18 were moderately differentiated OSCC and 2 were poorly differentiated OSCC. ORM1 staining was evaluated by a semiquantitative method, and CD34-positive blood vessels were quantified to calculate the MVD. The results were statically analyzed.

RESULTS

All cases exhibited immunoexpression of ORM1 and CD34. However, no significant differences were found between the expression of both markers among the histological grades. In addition, the presence of ORM1 in inflammatory cells and in the extracellular matrix was detected in most cases.

CONCLUSION

These results suggest that the induction of angiogenesis is not the main role of ORM1 in OSCC and may be associated with the regulation of the immune/inflammatory response or the transport of protumoral molecules, such as sialyl-Lewis X or phorbol esters, which requires confirmation in future studies.

Microvessel Density in Patients with Cutaneous Melanoma: An Up-to-Date Systematic Review and Meta-Analysis

Background

We conducted a meta-analysis, in order to appraise the effect of microvessel density (MVD) on the survival of patients with cutaneous melanoma.

Methods

This study was conducted according to the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. A systematic literature search in electronic databases (MEDLINE, Web of Science, and Cochrane Central Register of Controlled Clinical Trials) was performed. Fixed Effects or Random Effects model was used, based on the Cochran Q test.

Results

In total 9 studies (903 patients) were included. Pooled HR for overall survival (OS) and disease-free survival (DFS) were 2.62 (95% CI: 0.71–9.60, p = 0.15) and 2.64 (95% CI: 0.82–8.47, p = 0.10), respectively. Odds ratios of overall survival between high and low MVD groups, at 12 (1.45, 95% CI: 0.16–13.24), 36 (2.93, 95% CI: 0.63–13.59), and 60 (4.09, 95% CI: 0.85–19.77) months did not reach statistical significance. Significant superiority of low MVD group, in terms of DFS, at all time intervals (OR: 4.69, p < 0.0001; OR: 2.18, p = 0.004; OR: 7.46, p = 0.01, resp.) was documented.

Discussion

MVD does not affect the HR of OS and DFS. A strong correlation with DFS rates at 12, 36, and 60 months was recorded.

Peritumoral D2-40 Chalkley score independently predicts metastases and survival in patients with cutaneous malignant melanoma

BACKGROUND

Many observational studies investigated the prognostic significance of angiogenesis and lymphangiogenesis in patients with melanoma. However, the obtained results are rather contradictory, probably due to the lack of the consensus methodology.

METHODS

To investigate the prognostic significance of angiogenesis and lymphangiogenesis-related parameters in patients with melanoma, we performed a retrospective investigation following the consensus recommendations for angiogenesis and lymphangiogenesis quantification in solid tumors and reporting recommendations for tumor marker (REMARK) criteria for reporting the results. Blood and lymphatic vessel Chalkley scores, endothelial cell proliferation fractions and microvessel densities were quantified using a double immunostaining for endothelial marker CD34 or lymphendothelial marker D240 and the proliferation marker Ki-67 in 196 patients with melanoma. These parameters were evaluated separately for peritumoral (PT) and intratumoral areas and were correlated with outcome.

RESULTS

In multivariate analysis PT D240 Chalkley score was identified as a strongest predictor for sentinel lymph node metastases, non-sentinel lymph node metastases, distant metastases, disease free survival and overall survival in patients with melanoma.

CONCLUSIONS

If additional studies corroborate our findings, we believe that the inclusion of PT D240 Chalkley counts to the routine pathology examination of melanoma samples would provide additional information for identifying high-risk patients.

Blood microvessel density, lymphatic microvessel density and lymphatic invasion in predicting melanoma metastases: systematic review and meta-analysis

In malignant melanoma (MM) there is an urgent need to identify new markers with predictive value superior to the traditional clinical and histological parameters. Angiogenesis and lymphangiogenesis have been recognized as critical processes in tumour growth and metastasis development, and numerous studies have evaluated the significance of these parameters in predicting the prognosis in solid tumours, including MM. We set out to determine whether angiogenesis, lymphangiogenesis and lymphatic invasion (LI) are valuable prognostic markers in MM. We systematically reviewed the available literature and subsequently performed a meta-analysis on the compiled data. To be eligible for the systematic review, a study had to provide the microvessel density (MVD), the lymphatic vessel density (LVD) or information about LI, assessed by immunohistochemistry on the primary site in patients with MM. To be evaluable for the meta-analysis, a study also had to provide information on clinical outcome. We approached selected studies with the Reporting recommendations for tumour marker (REMARK) criteria, verifying whether they had followed the recommendations. In total, nine angiogenesis, seven lymphangiogenesis and 10 LI studies were included in our meta-analysis, representing 419, 474 and 802 patients, respectively. Using meta-analysis, we showed that peritumoral LVD and the presence of LI have prognostic value for patients with MM. In contrast, MVD and intratumoral LVD did not have prognostic value in these patients. LVD and LI seem to have prognostic value for patients with MM.

Mechanisms of tumour vascularization in cutaneous malignant melanoma: clinical implications

Malignant melanoma represents < 10% of all skin cancers but is responsible for the majority of skin-cancer-related deaths. Metastatic melanoma has historically been considered as one of the most therapeutically challenging malignancies. Fortunately, for the first time after decades of basic research and clinical investigation, new drugs have produced major clinical responses. Angiogenesis has been considered an important target for cancer treatment. Initial efforts have focused primarily on targeting endothelial and tumour-related vascular endothelial growth factor signalling. Here, we review different mechanisms of tumour vascularization described in melanoma and discuss the potential clinical implications.

Lymphangiogenesis: implications for diagnosis, treatment, and prognosis in patients with melanoma

Disease course in melanoma often cannot be accurately predicted by means of the prognostic factors usually considered in patients with melanoma; therefore, new factors are clearly needed. Increasingly robust scientific evidence shows that tumor lymph vessels play a key role in melanoma that metastasizes by lymphatic and hematogenous pathways. We review current knowledge and examine the implications of lymphangiogenesis in the diagnosis, treatment, and prognosis of patients with melanoma.

Blood vessel maturation, vascular phenotype and angiogenic potential in malignant melanoma: one step forward for overcoming anti-angiogenic drug resistance?

Angiogenesis is a pivotal process for growth, invasion and spread of the majority of solid tumors including melanoma. Anti-angiogenic agents have not been systematically tested in patients with advanced melanoma. Clinical efficacy of angiogenesis inhibitors targeting endothelial cells has not been as affirmative as initially hoped and improved clinical outcomes have been observed in combination with chemotherapy or additional drugs for many types of human cancer. However, angiogenesis is not only dependent on endothelial cell invasion and proliferation, it also requires pericyte coverage of vascular sprouts for stabilization and maturation of vascular walls. Recent data suggest that pericytes might be able to confer resistance to anti-vascular endothelial growth factor (VEGF) therapy. This review will focus on the significance of the vascular phenotype but also on the impact of pericyte-mediated vessel maturation for the susceptibility to anti-angiogenic therapy, including malignant melanoma, which we identified as crucial factor regarding therapeutic efficacy.

Chapter 14. Measuring intratumoral microvessel density

For a tumor to grow beyond a limited volume of 1-2 mm(3), the tumor cells must not only proliferate, but they must be able to induce the growth of new capillary blood vessels from the host. As early as 1971, it was proposed that tumor growth was dependent on angiogenesis; and, that tumor cells and blood vessels composed a highly integrated ecosystem, that endothelial cells could be switched from a resting state to one of rapid growth by a diffusible signal from tumor cells, and that anti-angiogenesis may become an effective anti-cancer therapy. Indeed, now there is considerable indirect and direct evidence to show that tumor growth is angiogenesis dependent, that tumor cells can produce diffusible angiogenic regulatory molecules, and that angiogenesis inhibitors can slow or prevent tumor growth, and that angiogenesis is a relevant target for anti-cancer therapy. Measuring intratumoral microvessel density (iMVD) in vascular "hot spots" has been shown to correlate with aggressive tumor behavior. This chapter reviews the techniques available for measuring iMVD.

Proliferating endothelial cells, but not microvessel density, are a prognostic parameter in human cutaneous melanoma

The induction of angiogenesis is crucial in the development of most human tumors. Angiogenesis is routinely assessed by the density of tumor microvessels. This technique reveals controversial results on the clinical and prognostic value of angiogenesis in melanoma. We investigated angiogenesis in tumor tissues of 58 cutaneous melanoma patients, of which a clinical follow-up of over 10 years was available, through assessment of microvessel density and by enumeration of the number of proliferating endothelial cells. To that end, vessels were immunohistochemically detected by CD31/CD34 staining, and proliferating endothelial cells were enumerated in a double staining with the proliferation marker Ki67. We found that microvessel density did not correlate with tumor stage or survival, neither in intratumoral nor in peritumoral areas. In contrast, proliferating endothelial cells were only observed in intratumoral areas and were correlated positively with tumor stage and the presence of distant metastases. In addition, a strong positive correlation was found with the number of proliferating tumor cells. Finally, high numbers of growing endothelial cells predicted short survival. Our results show that angiogenesis could best be measured by enumeration of proliferating endothelial cells and that this parameter has prognostic value in patients with cutaneous melanoma.

Pericyte-like location of GFP-tagged melanoma cells: ex vivo and in vivo studies of extravascular migratory metastasis

Previous studies have demonstrated that some tumor cells occupy a pericyte-like location in melanoma, forming angio-tumoral complexes. We hypothesized that these tumor cells are migrating along the abluminal surface of the endothelium, a mechanism termed "extravascular migratory metastasis." In the present study, we have used human and murine melanoma cells that stably express enhanced green fluorescence protein (GFP) to examine, in an ex vivo co-culture model, melanoma cell interactions with vessels that have sprouted from rat aortic rings. We also used in vivo tumor growth on the chick chorioallantoic membrane (CAM) to observe the dissemination pathway of melanoma cells. In the ex vivo rat aorta system, we observed a pericyte-like location of tumor cells that were spreading along the vascular channels. For examination of the CAM in vivo, we have used the Lugassy preparation, allowing one to obtain striking images of the relationship between fluorescent GFP cells and microvessels. Melanoma cells were found cuffing the outside of vessels around the tumor. Tumor cells were observed along the vessels several centimeters from the tumor. Confocal microscopy and histopathology confirmed the pericyte-like location of tumor cells, without any observable intravasation. The results indicate that melanoma cells can migrate along the abluminal surface of vessels. This study also demonstrates that these models can provide quantitation analysis that may prove useful in elucidating the molecular interactions involved in extravascular migratory metastasis.

From bioactive substances to research on breast-feeding promotion

Despite known health benefits, exclusive breast-feeding for at least 4 months is uncommon in many countries. In Mexico, most mothers initiate breast-feeding but few breast-feed exclusively.

OBJECTIVE

The objective was to examine the effectiveness of home visits by lay peer counselors to increase exclusive breast-feeding among mothers in a periurban area of Mexico.

METHODS

An ethnographic assessment conducted in 1994 that identified key maternal beliefs, practices, and needs was used to guide educational strategies. Lay counselors were recruited from the same community and trained by La Leche League. From March 1995 through September 1996, pregnant women were identified by community census and invited to participate. Women were enrolled into a randomized, controlled study of 3 groups: no intervention (control), 3 visits, and 6 visits during pregnancy and early postpartum. Data collection was performed by a social worker apart from the counselors. Exclusive breast-feeding was defined by WHO criteria.

RESULTS

The study enrolled 130 women; 52 were in the 3-visit group, 44 in the 6-visit group, and 34 in the control group. Study groups did not differ in the maternal characteristics or initiation of breast-feeding (96%). At 3 months postpartum, exclusive breast-feeding was practiced by only 12% of controls vs. 52% in the 3-visit group and 67% in the 6-visit group (P < 0.001, log rank test). In the first 3 months, significantly (P = 0.037) fewer intervention than control infants had an episode of diarrhea (11% vs. 26%, respectively). Intervention effectiveness was independent of maternal factors or birth hospital.

CONCLUSIONS

This unique experimental study demonstrated a dramatic increase in exclusive breast-feeding and a significant reduction in infant illness in an urban community through well-designed maternal support including early intervention and repeated contact.

Relationship of tumorigenic malignant melanomas to dermal elastin: an expression of tumor/stromal interaction that may be related to prognosis

Malignant melanomas, which produce a large number of substances active in connective tissue modulation, must contend with the dermis to grow and propagate. We studied the morphologic interactions between tumorigenic malignant melanomas and dermal elastin. Formalin-fixed and paraffin-embedded tissues of 108 tumorigenic malignant melanomas were stained for elastic tissue with the Verhoeff-van Gieson method. Various aspects of the relationship between malignant melanoma and dermal elastin were analyzed in relation to the histologic and clinical data using univariate and multivariate analyses. Tumor thickness, mitotic rate, and the presence of elastin remnants within the tumors were found to be independent negative prognostic factors, the latter with borderline significance. Tumors with more remnants of elastin were associated with higher stage of disease and lymph node and distant metastases. Tumor infiltration between the elastic fibers in the tumor depth was associated with high Clark level, greater tumor thickness, high stage of disease, and lymph node metastases. At least partial preservation of elastic fibers in the tumor depth was a relatively good prognostic factor whereas complete absence of elastin was an adverse factor. Focal or multifocal absence of elastin in the midst of the tumors or in their depth was usually associated with lymphocytic infiltrates. We suggest that tumors with remnants of elastic fibers and/or invasion between elastic fibers in their depth may be fast growing and highly invasive. The absence of elastin within tumors and at their advancing edge may be related to the elaboration of elastin-degrading substances by melanoma cells or various inflammatory cells. Our findings indicate that the relationship between malignant melanomas and dermal connective tissue components, specifically elastin, may have prognostic significance.

Lymphangiogenesis in malignant tumours: Does it occur?

The development of a vascular bed is essential for solid tumour growth and metastasis. In many tumours, mean vascular density can be related to the rate of metastasis and, therefore, to prognosis. In other tumour types, such as cutaneous melanoma and head-and-neck squamous cell carcinoma, this relation is absent. Until now, the reason for this has been unclear, but since these particular tumour types are also known for their propensity to spread via the lymphatic system, it may be speculated that the presence of a pre-existing lymphatic bed and the formation of new lymphatics (lymphangiogenesis) are important factors. Growth factors involved in lymphangiogenesis during embryogenesis have been recently identified and these are also expressed in many tumour types, but the existence of tumour-induced lymphangiogenesis has not so far been reported. Partly, this could be due to the lack of reliable endothelial markers, thereby hampering a consistent evaluation of lymphatic vasculature. This editorial discusses the role of the lymphatic bed in mediating the metastasis of solid tumours, summarizes known methods to detect lymphatics, and proposes a hypothetical mechanism of tumour-induced lymphangiogenesis.

Vasculogenic mimicry and tumor angiogenesis

Tumors require a blood supply for growth and hematogenous dissemination. Much attention has been focused on the role of angiogenesis-the recruitment of new vessels into a tumor from pre-existing vessels. However, angiogenesis may not be the only mechanism by which tumors acquire a microcirculation. Highly aggressive and metastatic melanoma cells are capable of forming highly patterned vascular channels in vitro that are composed of a basement membrane that stains positive with the periodic acid-Schiff (PAS) reagent in the absence of endothelial cells and fibroblasts. These channels formed in vitro are identical morphologically to PAS-positive channels in histological preparations from highly aggressive primary uveal melanomas, in the vertical growth phase of cutaneous melanomas, and in metastatic uveal and cutaneous melanoma. The generation of microvascular channels by genetically deregulated, aggressive tumor cells was termed "vasculogenic mimicry" to emphasize their de novo generation without participation by endothelial cells and independent of angiogenesis. Techniques designed to identify the tumor microcirculation by the staining of endothelial cells may not be applicable to tumors that express vasculogenic mimicry. Although it is not known if therapeutic strategies targeting endothelial cells will be effective in tumors whose blood supply is formed by tumor cells in the absence of angiogenesis, the biomechanical and molecular events that regulate vasculogenic mimicry provide opportunities for the development of novel forms of tumor-targeted treatments. The unique patterning characteristic of vasculogenic mimicry provides an opportunity to design noninvasive imaging techniques to detect highly aggressive neoplasms and their metastases.

Stochastic relationship between the growth fraction and vascularity of thin malignant melanomas

Tumour vascularity has been proposed as a prognostic indicator for a number of solid tumours. In these respects the situation is unclear for cutaneous malignant melanoma (MM). The small number of MM cases studied to date have indicated controversial preliminary conclusions. Hence, tumour thickness remains currently the most reliable prognostic factor for MM. This variable has been shown in previous work to be correlated with both the S-phase fraction and the growth fraction of the MM cells. We studied the relationship between vascularity and growth fraction of 100 thin (< 1 mm) cutaneous MM using immunohistochemistry (Ulex europaeus agglutinin-type 1 (UEA-1) and MIB-1 antibody (Ki-67)) and computerised image analysis. A stochastic relationship was found between intra- and peritumoral vascularity, and between Ki-67 and UEA-1 measures. Approximately 20-40% of PC-MM showing a high Ki-67-positive growth fraction (breakpoint: 30/0.4 mm2) were characterised by a prominent vascularity at the boundary of the neoplasm. In these cases, vessels often exhibited either heterogeneous lumen sizes or a uniform prominent dilated network. The present study shows that the angiogenic phenotype of MM occurs as a stochastic event during neoplastic progression. Its expression is not mandatory for reaching high values in MM growth fraction. It can be hypothesised that the absence of a link between proliferation and vascularity might account for the unusual outcome of some cutaneous MM, including the dormant growth-stunted type and the metastasising thin MM.

Quantification of vascularity in nodular melanoma and Spitz's nevus

Spitz's nevi are acquired benign melanocytic skin tumors. Usually they are differentiated from nodular melanoma by clinical and histopathological criteria. Since Spitz's nevi are one of the most common simulators of nodular melanomas their bizarre histopathology may cause diagnostic confusion and make it difficult to differentiate these two melanocytic tumors. One of the histologic features shared by Spitz's nevus and nodular melanoma is prominent vascularity. The ability of malignant melanoma to induce angiogenesis is well established whereas benign melanocytic tumors do not have a prominent overall vascularity. The purpose of this study was to find out whether the degree of vascularity of nodular melanomas differs significantly from that of benign Spitz's nevi. In this study the number of microvessels and the vessel area were determined in 23 Spitz's nevi and 16 nodular melanomas. The number of microvessels and the vessel area were determined on Ulex Europaeus agglutinin I-stained sections by computer-assisted image analysis. Two methods of measurement were used, namely systematic and selective sampling. Measurement of the whole tumor specimen (systematic sampling) revealed a vessel count of 10.83/field (SD +/-5.97) for Spitz's nevi whereas nodular melanomas exhibited a significantly lower (p=0.04) vessel count of 6.44/field (SD +/-3.85). This difference was even more pronounced when the vessel area (Spitz's nevi: 17.85x10-4mm2, SD +/-10.32; nodular melanomas: 7.88x10-4mm2, SD +/-5.23) was investigated (p < 0.001). The difference in vessel area and vessel count was insignificant for areas exhibiting the greatest vascularity (selective sampling). Measurement of vessel count and vessel area lead us to conclude that Spitz's nevi have a significantly higher vascularity than do nodular melanomas. Our results thus indicate that angiogenesis in these pigmented lesions is not correlated with malignancy.

Angiogenesis as a biologic and prognostic indicator in human breast carcinoma

In this review we describe angiogenesis pathways involved in the development of breast carcinoma. Different assessment techniques for angiogenesis and their optimisation are discussed. Angiogenesis is an important factor for prognosis and will be increasingly important in therapeutic decisions.

Vascular density in melanoma xenografts correlates with vascular permeability factor expression but not with metastatic potential

We studied the relation between tumour vascular density and tumour growth rate, metastatic incidence and vascular permeability factor (VPF) mRNA levels in a human xenograft model described previously. Vascular density was determined by automated image analysis. Xenografts derived from cell lines BLM and MV3 showed the highest mean vascular density (MVD), the highest in vivo growth rate, high VPF mRNA levels and rapid development of lung metastases. Xenografts of cell lines M14, Mel57 and MV1 showed a significantly lower degree of vascularization, lower in vivo growth rates and lower levels of VPF mRNA, but formed lung metastases with a similar incidence as those of BLM and MV3. Xenografts from cell line 1F6 did not form lung metastases, whereas tumours derived from a spontaneous mutant of 1F6, designated 1F6m, gave rise to lung metastases to the same extent as Mel57, M14 and MV1 tumours. MVD values in 1F6 and 1F6m xenografts, VPF mRNA levels and in vivo growth rates of 1F6 and 1 F6m xenografts, however, were similar. In conclusion, in the melanoma xenograft model vascular density is correlated with in vivo growth rate and with in vitro VPF mRNA levels, but not with the ability to metastasize.

Markers of tumor angiogenesis: clinical applications in prognosis and anti-angiogenic therapy

Numerous studies in many tumor types have demonstrated that quantitation by microvessel as a measure of angiogenesis is a powerful prognostic tool. However, the ability to exploit tumor angiogenesis as a prognostic marker is limited by the methods currently used for capillary identification and quantitation. This report critically evaluates all aspects of the techniques and their associated problems used for assessing tumor angiogenesis in tissue sections including the area of tumor assessed, the vascular parameter measured, the method of quantitation, the stratification of patients and the practical utility of computer image analysis systems. The potential of angiogenic factors assays, proteolytic enzymes, and cell adhesion molecules as surrogate endpoints for quantifying tumor angiogenesis are discussed and other methods for quantifying tumor angiogenesis are described. The potential clinical applications of these angiogenic markers in prognosis, stratification for adjuvant treatments (both cytotoxic and anti-angiogenic/vascular targeting) and other aspects of patient management is also discussed, particularly design of phase I and II trials.

Tumor vascularity as a prognostic indicator in intermediate-thickness (0.76-4 mm) cutaneous melanoma. A quantitative assay

Tumor vascularity has been reported to be a prognostic factor in solid tumors. We studied the prognostic value of tumor vascularity in 19 primary stage I skin melanomas. Only intermediate-thickness melanomas (0.76-4.00-mm thick) were studied. They were treated surgically to provide two groups of patients. The first group of 11 patients had no evidence of metastases after a follow-up of a mean period of 72.36 months, whereas the second one developed metastases in a mean period of 46.87 months. The two groups were matched for important prognostic factors including tumor thickness, sex, and age. Vascularity was quantified by a morphometric stereological analysis on paraffin sections stained with anti CD31 monoclonal antibody. The percentage of vascular area was significantly higher in the metastasizing group than in the nonmetastasizing one. Our study suggests that increased vascularity may have a prognostic significance in intermediate-thickness melanoma.