Cancer progression and monocyte inflammatory dysfunction: relationship to tumour excision and metastasis

In a longitudinal study performed before and after surgical resection of a chemically-induced, transplanted rat tumour we found that a monocytosis- and tumour-induced anti-inflammatory effect directed against macrophages was promptly corrected by tumour excision but recurred with metastasis. These observations indicate that the monocyte abnormalities are acquired and related to cancer progression. The anti-inflammatory effect required relatively large primary or metastatic tumour burdens. Our findings support the clinical impression that monocyte abnormalities are associated with a poor prognosis.