Computer-assisted morphometric analysis of lymphatic vessel changes in hamster tongue carcinogenesis.

BACKGROUND

To characterize lymphangiogenesis in early-stage hamster tongue carcinoma development, morphological features and spatial relationships of lymphatic vessels.

METHODS

Lymphatic vessels were examined histochemically, using 5'-Nase-ALPase enzyme and combined light and electron microscopy to measure lymphatic vessel area (LVA) and lymphatic vessel density (LVD).

RESULTS

In atypical hyperplastic tissues, LVA was found to be 1429.97 and LVD was found to be 39, in carcinoma in situ LVA was 2538.33 and LVD was 48, and in micro-invasive carcinoma LVA was 5733.74 and LVD was 59. Increased lymphangiogenesis was seen in pre-neoplastic states and in early-stage oral squamous cell carcinoma (OSCC). Small regular lymphatic vessels predominated in atypical hyperplasia, and large, irregular lymphatic vessels in early-stage OSCC. Lymphatic endothelial vessels were stretched and porous over large areas.

CONCLUSIONS

Newly formed lymphatics and patulous intercellular junctions may be optimally suited for tumor cell metastasis through lymphatic channels in early- and middle-phase carcinogenesis. Lymphatic capillary LVA and LVD became enlarged, and positively correlated, with malignancy, but show no correlation with 7,12-dimethylbenz[a]anthracene-induced time.