We present the case of a 58-year-old man who presented to the emergency department with severe ocular pain accompanied by progressive visual loss in his left eye. Ophthalmological examination revealed a pigmented mass in the iridocorneal angle that protruded into the anterior chamber and affected the iris. The patient's symptoms were compatible with acute glaucoma secondary to this mass in the anterior chamber. Ophthalmoscopy showed a large pigmented mass with an irregular appearance, with more raised areas. Ocular ultrasound findings were compatible with a large, diffusely spreading ocular melanoma. Magnetic resonance imaging (MRI) showed a mass with a base of 17 mm, slightly hyperintense in T1 and hypointense in T2, compatible with the diagnosis of choroidal melanoma (1). The oncology department performed an extension study which ruled out metastatic dissemination. Given the extent of the tumour, the patient's symptoms and the absence of any possibility of visual recovery, treatment by enucleation was considered (1,3).

Macroscopic visual examination of the eyeball after removal revealed the presence of scleral invasion. The patient evolved favourably, retaining ocular motility and a satisfactory appearance with the external ocular prosthesis, maintaining a good quality of life, presenting only difficulty in performing daily tasks requiring good binocular vision.
Macroscopic examination of serial sections of the eyeball showed a circumferential mass of endophytic growth covering practically the entire choroid extending to the ciliary body and iris, corresponding histologically to a proliferation of spindle and epithelioid cells with large, pigmented cytoplasm, oval nuclei with prominent nucleoli with a significant degree of atypia. The number of mitoses was high, with evidence of haemorrhagic and necrotic foci. These anatomopathological data confirmed the diagnosis of diffuse uveal melanoma, with perforation of the scleral wall reaching the external surface of the sclera.

