Colonic and rectal cancer

1. Big picture

Colorectal cancer (CRC) means malignant epithelial tumour of the colon or rectum, most commonly adenocarcinoma. It is one of the most important surgical oncology topics because surgery is the only potentially curative treatment, but correct management depends on:

1. Tumour location — right colon, left colon, sigmoid, rectum.
2. Stage — local depth, lymph nodes, distant metastases.
3. Emergency presentation — obstruction, perforation, bleeding, peritonitis.
4. Rectal cancer-specific anatomy — mesorectum, sphincter, pelvic nerves, circumferential resection margin.
5. Multimodal treatment — surgery ± chemotherapy ± radiotherapy, especially for rectal cancer.

Core oral-exam sentence:

Colorectal cancer is usually adenocarcinoma arising through the adenoma–carcinoma sequence; diagnosis is by complete colonoscopy with biopsy, staging by CT and rectal MRI when needed, and curative treatment is radical oncological resection with lymphatic drainage, with neoadjuvant treatment especially important in rectal cancer.

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