He is a light complected Caucasian with Type II skin. The lesion is solitary, 9 mm in diameter. It had a peculiar reddish brown color.
Clinical Photo:
Dermatoscopic Image |
Pathology:
Shows that this is a cellular dermatofibroma with monster cells.
Photomicrographs courtesy of Dr. Jag Bhawan.
4x |
10x |
20x |
Reference:
Dermatofibroma with monster cells.
Tamada S, Ackerman AB. Am J Dermatopathol.
1987 Oct;9(5):380-7.
Abstract: Nineteen cases of dermatofibroma associated with monster cells
are reported. The term "monster" (an animal with a strange or
terrifying shape, one unusually large for its kind) implies a strikingly
atypical cell with an extremely large nucleus. Except for monster cells, these
19 lesions had all of the typical histopathological findings of dermatofibroma.
The clinical diagnosis for 16 of these lesions was dermatofibroma (or
histiocytoma). Three lesions were submitted without any clinical diagnosis.
Eighteen of 19 lesions occurred on the extremities. One was on the back.
Monster cells are seen in the early, histiocytic stage of dermatofibroma when
lipophages and/or siderophages are usually present in large numbers. Only
rarely were mitotic figures seen in dermatofibromas with monster cells, and
they were neither numerous nor atypical. It is important for histopathologists
to distinguish dermatofibroma with monster cells from cutaneous malignant
fibrous histiocytoma and radiation sarcoma. The criteria for differentiation
concern primarily the architectural pattern of the lesion rather than its
cytological features.