# Cancer

> Citation bundle for Cancer on The Treatment Registry.
> URL: https://thetreatmentregistry.com/conditions/cancer
> Bundle URL: https://thetreatmentregistry.com/api/citations/conditions/cancer

## Description

Cancer treatment varies fundamentally by tumour type, stage, biology (including molecular profile), and patient fitness. Modern oncology is multimodal and increasingly precision-driven, combining surgery, radiotherapy, systemic therapies (chemotherapy, targeted therapy, immunotherapy, hormonal therapy), and supportive care. Continuity of care across the treatment course is critical, which makes cross-border treatment particularly difficult to coordinate.

## Treatment ladder

### conservative

- **Active surveillance / watchful waiting** — For selected indolent cancers (low-risk prostate, some early thyroid and chronic lymphocytic leukaemia), structured surveillance with intervention deferred until progression. Avoids treatment morbidity in patients who may never need active treatment.
- **Best supportive care** — Symptom-focused care without disease-modifying treatment, appropriate when curative or life-prolonging treatment is not feasible or not in the patient's interest.

### procedural

- **Chemotherapy** — Systemic cytotoxic anti-cancer therapy, delivered as cycles of intravenous or oral drugs. Indications, regimens, and protocols are tumour- and stage-specific.
- **Radiotherapy** — External-beam, brachytherapy, or systemic radioisotopes. Used as primary therapy, adjuvant therapy, or palliation depending on the cancer.
- **Targeted therapy and immunotherapy** — Drugs targeting specific molecular alterations (kinase inhibitors, monoclonal antibodies) or immune checkpoints (PD-1/PD-L1 inhibitors). Eligibility depends on tumour molecular profiling.

### surgical

- **Curative oncologic surgery** — Resection of localised tumour with margins, often combined with regional lymphadenectomy. Cornerstone of curative treatment for most solid tumours when surgically resectable.
- **Cytoreductive (debulking) surgery** — Removal of as much tumour bulk as possible to improve response to subsequent systemic therapy; commonly used in ovarian cancer.
- **Palliative surgery** — Surgery to relieve symptoms (e.g. obstruction, pain) when cure is not the aim.

## Related procedures

- https://thetreatmentregistry.com/procedures/chemotherapy

## Sources

- [ESMO — Clinical Practice Guidelines](https://www.esmo.org/guidelines) — European Society for Medical Oncology (accessed 2026-05-09)