Lymphatic vessel density in primary melanomas predicts sentinel lymph node status and risk of metastasis.
OBJECTIVE
Important prognostic factors in patients with cutaneous melanoma include primary tumour thickness/depth of invasion, ulceration and mitotic rate, and the presence of tumour cells in regional lymph nodes. More recently, features of stromal components, such as blood and lymphatic vessel density, have been suggested as additional indicators of metastatic potential. Our aim was to investigate the relationship between tumour lymphatic vessels and lymph node metastasis.


RESULTS
Metastasizing (n = 11) and non-metastasizing (n = 11) primary melanoma samples matched for depth/thickness, mitotic rate and ulceration were examined for lymphatic vessel density (LVD) in the primary tumour, using an antibody to podoplanin. Significant differences were found between LVD (vessels/unit area) in the peripheral (5.73 ± 0.67) versus central (1.72 ± 0.42) regions of the metastasizing tumour group (P < 0.001), and between LVD in the peripheral areas of metastasizing (5.73 ± 0.67) versus non-metastasizing (4.21 ± 0.37) tumours (P < 0.01). No overall difference was found between total average LVD in the two tumour groups or between their vessel morphology.


CONCLUSIONS
Our results show that LVD is associated with risk of lymph node metastasis. Furthermore, the ratio of peripheral LVD:central LVD is a useful marker of primary melanomas that are likely to metastasize to lymph nodes.
Ludwig Institute for Cancer Research, Parkville, Vic., AustraliaDepartment of Surgery, Royal Melbourne Hospital, University of Melbourne, Vic., AustraliaJack Brockhoff Reconstructive Plastic Surgery Research Unit, Royal Melbourne Hospital and Department of Anatomy, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Vic., AustraliaTumour Angiogenesis Program, Peter MacCallum Cancer Centre, East Melbourne, Vic., AustraliaTissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, NSW, AustraliaThe University of Sydney, Sydney, NSW, AustraliaMelanoma Institute Australia, North Sydney, NSW, AustraliaThe Sir Peter MacCallum Department of Oncology, University of Melbourne, Vic., Australia.
Ramin
R
Shayan
Tara
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Karnezis
Rajmohan
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Murali
James S
JS
Wilmott
Mark W
MW
Ashton
G Ian
GI
Taylor
John F
JF
Thompson
Peter
P
Hersey
Marc G
MG
Achen
Richard A
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Scolyer
Steven A
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Stacker
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D042583:Lymphangiogenesis / Q000502:physiology*; D008207:Lymphatic Metastasis / Q000473:pathology; D042601:Lymphatic Vessels / Q000473:pathology*; D008297:Male; D008545:Melanoma / Q000473:pathology*; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000473:pathology*