Tumors can spread through direct extension into surrounding tissues, through the lymphatic or vascular systems, or by transcoelomic spread through body cavities. Lymphatic spread is common for carcinomas and follows drainage routes to regional lymph nodes. Vascular spread occurs via blood vessels either as tumor emboli or growing along vessel walls. Certain primary tumors have tendencies to metastasize to specific organs, such as prostate cancer spreading to bone. Transcoelomic spread involves cavities such as the peritoneal, pleural, or pericardial spaces, potentially causing malignant ascites or pleural effusions. Perineural spread grows along nerve bundles.

1. Spread of Tumours

9. Lymphatic spread

18. Secondary carcinoma of lung

19. Secondary deposits in lung