Basal cell carcinoma - an in-vivo model of human tumour microcirculation?

The role of angiogenesis in tumour growth and metastasis is well establishe d. However, investigations of tumour microcirculation to date have used eit her biopsy material from human tumours, or animal models in vivo. We have s tudied the tumour microcirculation in vivo in human skin cancers using vide o-microscopy to examine 12 basal cell carcinomas (BCCs) on the head and nec k of 11 patients, and compared the vessels with those seen in the peri-lesi onal skin, and in normal control skin on the opposite side of the body. The vessels seen within the BCCs were markedly abnormal qualitatively, forming bizarre, disorganized patterns. Quantitative analysis revealed that the me an diameter (+/-standard deviation) of the largest vessel was significantly greater within the BCC (0.086+/-0.029 mm) than that in the control skin (0 .034+/-0.012 mm) (P<0.001). The area fraction, a measure of the area of tis sue occupied by vessels, was increased highly significantly within the BCCs (0.158+/-0.038) compared with both peri-lesional skin (0.029+/-0.012) and control skin (0.027+/-0.010) (P<0.001). Length density, the length of blood vessel per unit area of tissue, was also highly significantly greater with in the lesion (210.22+/-66.05 cm(-1)) compared to peri-lesional (27.10+/-15 .67 cm(-1)) and control skin (28.27+/-15.81 cm(-1)) (P<0.001). This is the first study to have demonstrated that BCCs possess a distinct tumour microc irculation which can be observed directly, and assessed quantitatively. Pro spective studies of tumour progression, possibly after intervention with an giogenesis inhibitors, are possible.