A 40-year-old lady with temporal field defects and galactorrhoea is most likely to have -
Temporal field defects in women with galactorrhoea suggests pituitary macroadenoma.
Increased secretion of prolactin causes amenorrhoea, galactorrhoea and the mass effect of the tumour on the optic nerve produces headache and visual field defect.
Pituitary macroadenoma
Craniopharyngioma
Lactational failure
Pregnancy