One-page cheat sheet
Cancer basics and staging
The language of oncology on one page
palsurgery.comFree surgical teaching
Benign or malignant
- Benign: slow, well defined, no invasion, never spreads
- Malignant: invades and can metastasise
- Carcinoma = epithelium (85–90%); sarcoma = connective tissue
- Melanoma, lymphoma and seminoma are malignant despite -oma
Steps to invasion
- Hyperplasia → metaplasia → dysplasia → carcinoma in situ → invasive cancer
- Carcinoma in situ has not crossed the basement membrane
- Colorectal: APC → KRAS → SMAD4 → TP53
TNM staging
- T primary tumour, N regional nodes, M distant spread
- Prefixes: c clinical, p pathological, yp after neoadjuvant
- Stage I–IV; stage IV = distant metastasis
- Grade (G1–G3) is differentiation, not spread
Margins and fitness
- R0 no tumour at the margin; R1 microscopic; R2 visible
- ECOG 0 fully active · 1 light work · 2 self-caring, up over half the day · 3 in bed or chair over half the day · 4 bedbound
- Stage + grade + margin + fitness decide the plan
Spread
- Carcinoma: lymphatics first; sarcoma: blood
- GI cancers → liver via the portal vein
- Peritoneal (transcoelomic): stomach, ovary, colon
- Sentinel node: first draining node; biopsy spares node-negative patients a clearance
Treatment timing
- Neoadjuvant: before surgery (rectum, oesophagus, stomach, some breast)
- Adjuvant: after surgery (stage III colon, many breast)
- Curative or palliative: decide the intent first
Emergencies
- Neutropenic sepsis: IV antibiotics within 1 hour
- Cord compression: whole-spine MRI, dexamethasone
- Tumour lysis: K, phosphate, urate up; calcium down
- SVC obstruction, hypercalcaemia, obstruction, bleeding
Exam pearls
- Tumour markers monitor; they do not screen
- Testicular mass: inguinal orchidectomy, never scrotal biopsy
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