Difficult to offer an opinion without a pic, but with a little more history we may be able to help.
What is the age and occupation of the pt? Meds, etc.
Are the lesions confined to both feet or does she have anhidrosis/eczema type hands too?
Localised keratoderma may present similary to diffuse hyperkeratosis and are often inherited as autosomal dominant, ie genetic. Both congenital and acquired forms of keratoderma can present in isolation or as part of a syndrome/other pathology. One type of acquired is keratoderma climactericum (‘Climacteric’ is used to describe the time around or preceding menopause) and is associated with obesity and hypertension. Aetiology is unknown, although endocrine factors would obviously play a part.
You say that the lesions are not `plaque-like`. At the start of the disorder, mild keratoses are sharply circumscribed and these gradually increase in size, forming scales and coalesce resulting in the diffuse hyperkeratosis presentation.
Dave attached some good docs on this here