A comparison of 4 methods for assessing tumor vascularity in carcinoma of the cervix

A comparison was made of four methods for assessing tumour vascularity in carcinoma of the cervix. Formalin fixed tumour sections were stained with Masson's trichrome and measurements were made of the percentage of tumour blood vessels, vascular density (i.e. the proportion of blood vessels in the stroma) and inter-capillary distance (ICD). ICD was also obtained on anti-Factor VIII stained sections. The assessment of tumour vascularity was shown to be operator-dependent. For all the methods examined, statistically significant differences were seen between the values obtained by two people independently scoring the same sections. Nevertheless, weak correlations were seen between the different scorers for all the methods with measurements of ICD giving the strongest correlations. Either weak or no correlations were seen between the various methods used for assessing the tumour vasculature. An evaluation was made of the ability of the various methods to predict patient outcome for patients a minimum of two years post treatment with radiotherapy alone. Only measurements of the percentage of tumour blood vessels were shown to correlate with patient outcome. These data highlight the importance of having a single individual obtain measurements of tumour vascularity and suggest that the method chosen to determine vascularity may influence the results obtained.