Quantitative analysis of lymph vessel characteristics in organ confined prostate cancer
C.G. van Niekerk, C.A. Hulsbergen-van de Kaa, J.O. Barentsz, J.A. Witjes and J.A.W.M. van der Laak
The objective of this study was to analyze the characteristics of lymphatic vasculature in normal and (peri)tumoral prostate tissue, applying accurate and objective quantification techniques based on digital image analysis.Radical prostatectomy specimens of 27 patients were selected containing organ confined peripheral zone tumors, which were restricted to one side of the prostate (pT2a). Lymph vessels were visualized by immunohistochemistry against D2-40. Lymphatic vessel density, perimeter, and area were assessed over the entire tumor and corresponding contralateral normal tissue. Also, morphology (area, perimeter, and diameter) of individual lymph vessels were measured in (peri)tumoral and normal tissue.No differences were found in the overall lymph vasculature between tumor and normal peripheral zone. However, the area, perimeter, and diameter of individual lymph vessel profiles were significantly decreased in (peri)tumoral as compared to normal tissue. No differences were seen for these parameters between peritumoral and tumoral area. Comparing the coefficient of variation between compartments (normal, (peri)tumoral), no differences were observed for any parameter.Although differences exist between the morphology of individual lymph vessels in tumor versus normal tissue, the overall vascular bed (number and summed area and perimeter of lymphatics per area unit tissue) is unaffected in tumor. Peritumoral lymphatics resemble lymphatics in tumor tissue rather than normal lymphatics.