Lhermitte-Duclos and Cowden diseases: breast cancer as an unusual initial presentation of these overlapping conditions.

The authors report the case of a woman presenting with breast cancer who subsequently developed neck pain and ataxia. She had a family history of breast cancer and Cowden disease. A MRI study of the brain revealed a lesion in the cerebellum consistent with Lhermitte-Duclos disease (LDD) and a lesion consistent with a meningioma in the temporal lobe. This case emphasises the importance of awareness of the overlap between LDD and Cowden disease.