GI · Organ at risk

Spleen

Educational Summary

Dose constraints

Esophagus & GE Junction

ScheduleConstraintSource
41.4 Gy / 23 fx
Preoperative
Mean <10 GyRCR spleen guidance
50.4 Gy / 28 fx
Definitive; also 50 Gy / 25 fx
Mean <10 GyRCR spleen guidance

If clinically appropriate. Above 10 Gy, hyposplenism risk rises.

Quoted from eviQ 1861 and eviQ 1865, checked 2026-09-29. Full table with references →

Anatomy

A soft organ in the left upper quadrant, behind the stomach and under the left diaphragm, next to the tail of the pancreas and the upper pole of the left kidney.

Function in the body

The spleen filters the blood, removes worn-out red blood cells and is part of the immune system.

Why it matters

The spleen was long ignored in planning, but UK guidance now recommends contouring it whenever it may be irradiated. A mean dose above about 10 Gy is linked to late loss of splenic function (hyposplenism) and a higher risk of serious infection, which may call for vaccination or preventive antibiotics. It matters most for gastroesophageal junction, stomach and pancreatic tail targets.

How to contour

The RTOG upper abdominal atlas (Jabbour 2014) shows the spleen among its consensus contours on the atlas images, but it does not give written boundaries for it. Written boundaries from an open published source: verified source required.

Further reading

Related concepts