ABSTRACT
<p><b>OBJECTIVE</b>To study the growth way of parotid pleomorphic adenoma and the relative factors.</p><p><b>METHODS</b>The histological slides of 97 cases of the primary parotid pleomorphic adenoma were examined for the state of intra-capsule infiltration and extra-infiltration. The relative relationships between the infiltration state and the histological type, relative amount of various components, size and course of the tumor were analysed to investigate the growth way and relative factors.</p><p><b>RESULTS</b>1. There were more chances to develop infiltration of tumor in which the major content was epithelium. The tumor was severer with the increasing of epithelium, and decreasing of mucous content and elongation of course of the disease. 2. The limitation of the extra-envelop infiltration and budding was 0.085 - 0.210 mm, so, the boundary of partial parotidectomy should be away from the 1 cm envelop.</p><p><b>CONCLUSION</b>The growth way of parotid pleomorphic adenoma is related to the histological types and characters, relative amount of various components and the course of the tumor.</p>