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Paper text:
dermatofibrosarcoma protuberans ( dfsp ) is a rare cutaneous soft tissue neoplasm first described by taylor in 1890 .
it is locally aggressive and has an infiltrative growth pattern but distant metastasis is uncommon .
it most commonly occurs in adults over the age of 30 and constitutes 2 - 6% of all soft tissue sarcomas .
mainstay of treatment is wide local excision , although mohs micrographic surgery ( mms ) emerges as an alternative approach .
first , there is an unusual occurrence of dfsp in breast and second , there is fibrosarcomatous change in the background of dfsp .
a 40-year - old male presented with chief complaints of lump in the central part of his left breast for 3 months .
he did not have any significant past history of illness and his family history was unremarkable . on examination , it was a firm , mobile , nodular , non - tender swelling and showed an area of ulceration on the overlying skin .
the lump grossly measured 6.5 cm  4 cm and the area of ulceration measured 3.2 cm  2 cm .
fine needle aspiration cytology ( fnac ) was done from the swelling and smears showed large number of ovoid- to spindle - shaped cells with mild to moderate nuclear atypia and scanty cytoplasm .
the cells were arranged discretely and also in some clusters in a myxoid background [ figure 1 ] .
histopathological examination of sections from tumor revealed a tumor composed of spindled - shaped cells having plump nuclei , arranged in intersecting fascicles and storiform pattern [ figure 3 ] .
the tumor cells showed nuclear pleomorphism and increased mitotic figures ( 8 - 10/10 high power field ) were seen in some areas [ figure 4 ] .
plexiform capillary network was seen in the background with areas of hemorrhage and myxoid change [ figure 5 ] . the tumor involved overlying skin , nipple and areola [ figure 6 ] .
surgical lines of resections were tumor - free and all the 19 lymph nodes dissected from axillary pad of fat showed reactive changes .
impression of histopathological examination was spindle cell sarcoma of left breast , and paraffin blocks of the tumor were subjected to immunohistochemical ( ihc ) test .
on ihc test , tumor cells were reactive to cd34 [ figure 7 ] and non - reactive to s-100 , smooth muscle actin , desmin , cytokeratin and epithelial membrane antigen .
ovoid to spindle shaped cells with mild to moderate nuclear atypia and scanty cytoplasm , arranged discretely and also in some clusters in a myxoid background tumour composed of spindled shaped cells with plump nuclei , arranged in intersecting fascicles and storiform pattern mitotic figures and nuclear atypia  high power view areas of myxoid change along with a capillary tumour involving overlying skin tumour cells stain positively for cd34
dfsp is classified among the fibroblastic / myofibroblastic tumors of intermediate malignancy ( rarely metastasizing ) .
histologically , it is characterized by diffuse infiltration of dermis and subcutis by neoplastic cells , which grow along the fibrous septa of the subcutaneous tissue and interdigitate with fat lobules , resulting in a honeycomb appearance .
the cells are uniform spindle - shaped containing plump or elongated wavy nuclei and arranged in predominantly storiform pattern .
the cellular atypia is then even more prominent with hyperchromatic nuclei and increased mitotic figures .
histologic subtype , high mitotic index , cellularity , size , location on the head and neck , and recurrent lesions are factors reportedly associated with higher recurrence rates . in our case too , in some areas , cytological atypia was marked and mitotic figures were increased ( 8 - 10/10 high power field ) .
immunohistochemical studies have shown moderate to strong staining of human progenitor cell antigen cd34 in tumor cells .
cd34 is a useful marker that allows differentiation of dfsp tumor cells from normal stromal cells and dermatofibroma ( df ) . in df ,
additionally , immunostaining using cd34 as a marker is helpful in identifying tumor cells at the surgical margins , particularly when treating recurrent dfsp , in which tumor cell fascicles are often interspersed with the scar tissue .
although cd34 and factor xiiia can differentiate most cases of dfsp and df , the overlap of cd34 and factor xiiia expression in both lesions indicates the need to identify other potential immunohistochemical markers .
recently , stromelysin-3 ( st3 ) was found to be a useful marker for the differential diagnosis of df and dfsp .
st3 is a member of the matrix metalloproteinase ( mmp ) family , which is believed to play a role in tissue remodeling during various processes , such as wound healing and tumor invasion .
st3 is expressed in the majority of cases of df , whereas dfsps are only rarely st3 positive .
most cases of dfsp feature a specific translocation of chromosomes 17 and 22 , which results in constitutive production of platelet - derived growth factor b chain ( pdgfb ) and stimulation of dfsp growth .
most authorities would suggest a margin of 2 - 3 cm of normal tissue from the gross tumor boundary . despite optimal surgical management ,
local and regional recurrences are detected in up to 17% of patients with classic dfsp .
nowadays , mms has been advocated by several authors as an alternative approach to the use of wide resection surgery with tumor - free margins .
on october 19 , 2006 , the us food and drug administration ( fda ) granted approval for imatinib , as a single agent for the treatment of adult patients with unresectable , recurrent , and/or metastatic dfsp . with limited clinical data to date , a response rate of
approximately 65% has been achieved among dfsp patients treated with imatinib ( recommended dose 800 mg / d ) .
a small subset of dfsp lacking the classic translocation t ( 17:22 ) seems to have no response to imatinib .
our case has been treated with left - sided modified radical mastectomy on the basis of fnac diagnosis but imatinib was not administered in postoperative period . to conclude , though dermatofibrosarcoma can arise in the trunk , its presentation as male breast lump is rare and focal areas of fibrosarcomatous change has made the case more unique .
close follow - up of the patient is required to detect any recurrence at the earliest .
dermatofibrosarcoma protuberans is a cutaneous soft tissue neoplasm with potential for local recurrence but distant metastasis is rare . 
 trunk and extremities are most commonly involved . this case presented as left - sided breast lump in a male patient . 
 the patient underwent left - sided modified radical mastectomy . 
 tissues were subjected to histopathological and immunohistochemical test subsequently . 
 the tumor cells showed storiform arrangement with nuclear pleomorphism and increased mitotic figures at places . 
 they were reactive to cd34 and non - reactive to s-100 , smooth muscle actin , desmin , cytokeratin and epithelial membrane antigen . 
 the diagnosis of dermatofibrosarcoma protuberans with areas of fibrosarcomatous change was given . 
 though trunk is a common site for this tumor but its presentation as male breast lump has made the case unique .