I was unable to find another example of a patient having more than one of these tumors in my literature search. Tumors of this type are prone to recur, mostly because the initial excision is often inadequate. This is related to the pattern of infiltration which may be asymmetrical, and which is characterized by infiltration of the subcutis by delicate strands of tumor that extend far beyond the main mass of the tumor.
Metastatic behavior is rare.
There has been emphasis placed on the diagnostic importance of cellular storiform figures within the dermis. The characteristic pattern of infiltration of the subcutis, however, is present, and this greatly facilitates making the diagnosis. This asymmetrical, patchy pattern of infiltration has been variously described as 'Swiss cheese-like', 'honeycomb', and 'lacelike'. Since cellular storiform figures can be found in the dermis in dermatofibromas and since dermatofibromas may extend into the subcutis, the importance of the recognition of the characteristic pattern of infiltration of the subcutis by a DFSP cannot be overly stressed. The spindle cells in DFSP are monotonous in appearance, and cytologic atypia is minimal or absent.