# Prophylactic cranial irradiation (PCI)

Source: https://onco.cc/terms/pci-term/  
OnCo record `pci-term` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Giving the brain a preventive dose of radiation (25 Gy in 10 sessions) before any metastasis can be seen, mainly in small-cell lung cancer, which spreads to the brain in over half of patients. Its value is disputed now that MRI surveillance is routine, and cognitive side effects push practice towards watching instead.

## Summary

Small-cell lung cancer spreads to the brain in over half of patients, and PCI (25 Gy in 10 fractions) halved brain relapse and improved survival in limited-stage disease in the 1990s meta-analysis. Its value in extensive-stage disease and in the era of routine MRI staging is disputed (the Japanese Takahashi trial found no benefit with MRI surveillance), so the SWOG S1827 MAVERICK trial is comparing PCI with MRI surveillance while cognitive side effects push practice toward surveillance. In childhood leukaemia it has been replaced by intrathecal chemotherapy.

## Fields

- Kind: Term
- Last checked: 2026-09-09
- Also known as: PCI; cranial irradiation

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Prophylactic_cranial_irradiation
- Wikipedia: https://en.wikipedia.org/wiki/Prophylactic_cranial_irradiation

## Connected records

- technologies: [Prophylactic cranial irradiation vs MRI surveillance](https://onco.cc/technologies/prophylactic-cranial-irradiation/)
- terms: [Brain metastases (intracranial disease)](https://onco.cc/terms/brain-metastases/), [Intrathecal therapy (lumbar puncture, Ommaya reservoir)](https://onco.cc/terms/intrathecal-therapy/), [Whole-brain radiotherapy (WBRT)](https://onco.cc/terms/wbrt/)
- cancers: [Acute lymphoblastic leukaemia](https://onco.cc/cancers/all-leukemia/), [Extensive-stage small-cell lung cancer](https://onco.cc/cancers/extensive-stage-sclc/), [Limited-stage small-cell lung cancer](https://onco.cc/cancers/limited-stage-sclc/), [Small-cell lung cancer](https://onco.cc/cancers/sclc/)
- fronts: [Radiation Therapy](https://onco.cc/fronts/radiation/)
- trials: [ADRIATIC](https://onco.cc/trials/adriatic/)

---
JSON: https://onco.cc/api/v1/entities/pci-term.json