Regional lymphadenectomy and tumor immunity.

This study sought to determine if tumor immunity was impaired by regional lymphadenectomy when performed at different stages of tumor growth. Regional lymphadenectomy significantly reduced tumor specific immunity when performed soon after tumor inoculation. However, removal of the regional lymph nodes later but before the tumor was clinically detectable did not affect the development of tumor immunity. Similarly, regional lymphadenectomy after the tumor was palpable did not decrease tumor immunity. Therefore, prior to the time that the tumor is clinically detectable, immunologic sensitization has become a systemic phenomenon and is no longer confined to the regional lymph nodes.