The specimen consists of slices from the cerebrum and cerebellum. In the upper specimen there
is pronounced dilatation of both lateral ventricles with thinning and fenestrationof the septum
pellucidum. In the lower slice there is pronounced dilatation of the fourth ventricle.
This 60 year old man was diagnosed with small cell carcinoma of the lung and treated
with chemotherapy and radiotherapy. He represented 10 months later with bilateral
papilloedema and bilateral lower limb weakness. On admission a C.T. scan showed
communicating hydrocephalus. Microscopic examination of the brain showed numerous deposits
of small cell carcinoma within the medulla, cerebellum and hippocampus.