High grade 3, muscle invassive urine bladder cancer

High grade neuroendocrine carcinoma (small cell carcinoma) of the bladder.
The tumour cells express CK (weakly), Synaptophysin, Chromogranin and TTF-1.
They are immunonegative for GATA-3 and p63.
The Ki-67 proliferation index is approximately 85%.
The tumour has invaded lamina propria and detrusor muscle.