Resident Rounds. Part III. A Case of Proteus Syndrome

May 2013 | Volume 12 | Issue 5 | Features | 586 | Copyright © May 2013

Amanda Pickert MDa and Harper Price MDb

aDepartment of Dermatology, Mayo Clinic, Scottsdale, AZ
bDepartment of Dermatology, Phoenix Children’s Hospital, Phoenix, Arizona



A 21 year-old female presented to dermatology for evaluation of growing tumors on her feet. Lesions were asymptomatic and appeared in early childhood. However, walking and wearing shoes was becoming difficult. Evaluations had been performed at institutions in Colorado and Florida many years ago, but records were unavailable. Per the patient, biopsies were performed at one of the institutions. Post-biopsy, she was instructed to apply imiquimod, but the tumors regrew within months of stopping treatment. No other interventions attempted and the patient was unaware of any diagnoses.
Relevant further history included an abdominal lipoma treated with surgical excision at the age of two, mild breast and chest asymmetry, and a left popliteal mass with MRI imaging performed in 2004 at an unknown institution. Birth and family history was unremarkable.

Physical Exam

On the right 4th toe there was a large, pink, exophytic tumor (Figures 1 and 2) with disfigurement of the distal phalanx and toenail. Similar but smaller lesions were present on the left 3rd and 4th toe. The left heel exhibited a pink cerebriform plaque (Figures 3 and 4) with a smaller similar lesion on the left medial sole. Prominent veins and varicosities were present on the left popliteal fossa with extension to the dorsal foot. Abdominal exam showed an asymmetrical crease with fullness of the left rib cage but no gross deformities. Breast asymmetry was present with left greater than right. Numerous small, light to dark brown, macules were appreciated on the extremities and trunk. The face showed no dysmorphic features. Hair, eyes, oral mucosa, and nails were normal.


The patient meets the general criteria and the criterion from category A (cerebriform connective tissue nevus) for a diagnosis of Proteus syndrome.
table 1
Proteus syndrome is a very rare disorder that can affect tissue from any embryonic germ layer. Eminent findings include the progressive disproportionate overgrowth of tissues, cerebriform connective tissue nevi (essentially pathognomonic), epidermal nevi, adipose dysregulation (lipomas), and vascular malformations. In addition to the plantar cerebriform connective nevi, our patient has both a vascular malformation and adipose dysregulation. Cerebriform connective tissue nevi can be found on the plantar foot, hand, alae, ear, and lacrimal puncta (from most to