Childhood cancers differ from adult cancers. Most arise from embryonal or blood-forming tissues rather than epithelium, grow quickly, and are often widespread at diagnosis — yet they are usually more sensitive to chemotherapy, and most children in high-resource settings now survive. Treatment is intensive and delivered through research-based protocols, so late effects of treatment matter for decades.

Warning signs of childhood cancer — unexplained pallor, fatigue, bruising or petechiae, prolonged fever or frequent infections, bone or joint pain (especially waking at night), limp, a new lump or swelling, persistent morning headache with vomiting, change in balance or gait, white pupil or new squint, unexplained weight loss.

• CBC with differential and peripheral smear (blasts, low platelets, anemia); bone marrow aspirate and biopsy confirms leukemia
• Lumbar puncture — CNS involvement in leukemia (and intrathecal chemotherapy at the same time)
• Tumor lysis labs: potassium, phosphate, uric acid, calcium, creatinine, LDH
• Imaging: MRI for brain and spine; CT or ultrasound of the abdomen; chest X-ray (mediastinal mass — sedation and lying flat can compromise the airway)
• Neuroblastoma: urine catecholamine metabolites (VMA and HVA), MIBG scan
• Wilms tumor: abdominal ultrasound and CT; avoid palpating the abdomen once the mass is known
• Biopsy with molecular and genetic markers to assign risk group
• Baseline organ function before treatment: echocardiogram (anthracyclines), hearing test (cisplatin, carboplatin), kidney function, pregnancy test in adolescents

Modalities — chemotherapy (combination protocols), surgery, radiation (limited in young children because of growth and cognitive effects), hematopoietic stem cell transplant (HSCT), targeted drugs, and immunotherapy.

ALL — risk-adapted phases: induction (remission), consolidation, delayed intensification, and maintenance (oral chemotherapy for about 2 years). CNS-directed therapy uses intrathecal chemotherapy; cranial radiation is now reserved for a small number of children because of late neurocognitive effects. Five-year survival in high-resource settings is about 90%. Relapsed or refractory B-cell ALL may be treated with blinatumomab or CAR T-cell therapy (cytokine release syndrome, neurotoxicity).

Solid tumors — Wilms: nephrectomy plus chemotherapy (± radiation); neuroblastoma: risk-based, from observation to surgery, chemotherapy, HSCT, and immunotherapy; osteosarcoma: chemotherapy before and after limb-salvage surgery or amputation; brain tumors: surgery, radiation, chemotherapy; Hodgkin: chemotherapy (e.g., ABVD-type regimens; newer regimens replace bleomycin with brentuximab vedotin or nivolumab in some protocols) ± radiation.

Key drugs and safety checks (doses are protocol- and body-surface-area-based and verified with a pediatric oncology reference)

Oncologic emergencies

• Tumor lysis syndrome (TLS) — highest risk with ALL (high WBC) and Burkitt lymphoma at the start of therapy. Hyperkalemia, hyperphosphatemia, hypocalcemia (secondary), hyperuricemia → acute kidney injury and dysrhythmias. Prevention: aggressive IV hydration without added potassium, allopurinol or rasburicase (contraindicated in G6PD deficiency; uric acid samples drawn after rasburicase go on ice or results are falsely low), frequent labs, strict intake and output, ECG monitoring; treat hypocalcemia only if symptomatic (calcium–phosphate precipitation)
• Hyperleukocytosis — very high WBC → leukostasis (respiratory distress, stroke); hydration; avoid unnecessary red cell transfusion
• Spinal cord compression (neuroblastoma, sarcomas) — back pain, leg weakness, bowel or bladder change → urgent steroids and imaging
• Mediastinal mass / superior vena cava syndrome — keep upright, avoid sedation, prepare airway support
• Febrile neutropenia — see the next topic

Listed in priority order.

1. Detect emergencies early — respiratory compromise with mediastinal mass; neurologic signs (spinal cord compression, raised ICP); TLS labs every 4–8 hours at the start of therapy, urine output, ECG changes; hypersensitivity during asparaginase or other infusions
2. Safe chemotherapy administration
   • Two-person verification of drug, dose (weight or body surface area), route, and protocol day
   • Vesicants: confirm blood return before and during infusion; stop immediately for pain, swelling, redness, or leakage at the site, leave the device in place, aspirate if possible, notify the provider, and apply the site-specific antidote and hot or cold pack per policy
   • Intrathecal drugs are handled separately from IV vinca alkaloids to prevent fatal route errors
   • Safe handling of hazardous drugs and body fluids (gloves, gowns; double-flush toilets per policy for 48 hours)
3. Preoperative Wilms tumor — post a "do not palpate abdomen" sign; handle and bathe gently (rupture spreads tumor); monitor BP
4. Postoperative care
   • Nephrectomy: strict intake and output — urine output reflects the remaining kidney; BP; bowel sounds (ileus)
   • Brain tumor: neuro checks, ICP precautions, position per surgeon (often avoid lying on the operative site after large tumor removal); watch for CSF leak, diabetes insipidus, and posterior fossa syndrome (mutism)
   • Amputation: stump elevation early per protocol, phantom limb pain is real and treated; body image support
5. Monitor organ toxicity — hearing, cardiac function, kidney function, neuropathy, glucose (steroids, asparaginase)
6. Fertility and growth — offer fertility preservation discussion before treatment in adolescents (sperm banking; ovarian options per center)
7. Psychosocial care — honest, age-appropriate explanations; preparation for procedures; involve child life specialists; support siblings

• Explain the protocol calendar, each drug's main side effects, and whom to call 24 hours a day
• Oral chemotherapy at home (e.g., mercaptopurine, methotrexate): wear gloves, do not crush unless instructed, give at the same time each day, store safely away from other children
• Report: fever, bleeding, severe vomiting, no urine, severe constipation or abdominal pain (vincristine), cough or shortness of breath, new back pain or leg weakness, headache with vomiting
• Red urine after doxorubicin is expected for 1–2 days; blood in urine after cyclophosphamide is not
• After nephrectomy (single kidney): avoid contact sports that risk abdominal blows, drink fluids, and report urinary infection symptoms promptly
• No NSAIDs or aspirin unless the oncology team approves; check before any new medicine, herbal product, or supplement
• Survivorship: lifelong follow-up with a survivorship care plan listing treatments received and screening needed (heart, hearing, hormones, fertility, learning, second cancers)

• ALL is the most common childhood cancer; brain tumors are the most common solid tumors
• Leukemia signs: pallor, petechiae, fever, bone pain
• Brain tumor: morning headache with vomiting, ataxia
• Wilms tumor: do not palpate the abdomen; after nephrectomy monitor urine output and BP
• Neuroblastoma: mass may cross midline; VMA/HVA in urine; watch for spinal cord compression
• High-dose methotrexate → leucovorin rescue guided by methotrexate levels
• Vincristine: neurotoxicity and constipation; never intrathecal
• Anthracycline → cardiotoxicity; cisplatin → hearing loss; bleomycin → pulmonary fibrosis; cyclophosphamide → hemorrhagic cystitis (mesna, fluids)
• TLS: high K⁺, high phosphate, low Ca²⁺, high uric acid — hydrate, allopurinol or rasburicase (not in G6PD deficiency)
• Cyclosporine after HSCT: monitor BP and kidney function
• Cranial radiation is now limited; late cognitive effects are a key reason