A
B
C
Figure 2: (A,B) H&E image of lesion at 200x and 400x, respectively. The lesion is comprised of long fascicles of spindled cells in a densly-collagenous
matrix. Cellular atypia and abnormal mitotic activity are not present. (C) Beta-catenin. Nuclear accumulation of beta-catenin is seen within the
lesional cells, suggesting desmoid-type fibromatosis.
Discussion (continued)
The wild-type APC protein suppresses
the function of beta-catenin whereas the
truncated form of APC in Gardner
syndrome patients leads to beta-catenin
accumulation within the nucleus that
subsequently drives the transcription of
several cell proliferation markers.
Furthermore, desmoid tumors are
hypothesized to arise in the context of
surgery trauma, because the insult drives
fibroblastic proliferation during the
formation of scar tissue. 7
Thus, our patient possessed several of
the risk factors for development of
desmoid fibromatosis, including iatro-
genic trauma in the form of root canal
therapy and the inherited APC mutation
from her Gardner’s syndrome.
Desmoid type fibrosis within bone
typically do not cause pain, unless the
lesion has encroached upon neural
tissue. 4-5 No disturbance of the inferior
alveolar canal was noted on the
panoramic radiograph, so it remains likely
that the pain experienced by the patient
was caused by an odontogenic infection
rather than the desmoid tumor.
Decisions regarding management of
desmoid tumors are controversial, since
the surgical insult increases the likelihood
that the lesion will grow or recur. The
recurrence rate after achieving clear
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