PECAM1 and neoplasm: Quantitation of the CD31+ areas within viable tumor tissue indicated a trend towards increased neovascularization after i.a. CDDP (4.1 ± 1.5 % of remaining viable tumor tissue) compared with the lower levels observed after i.a. vehicle (1.8 ± 0.7 %), i.v. CDDP (1.6 ± 0.2 %) or i.v. vehicle treatment (1.3 ± 0.2 %; Fig. 5e).