Case Presentation
A 48-year-old otherwise healthy Caucasian woman presented with two weeks
history of a painless lump in the right breast. There was neither
history of trauma nor chest wall irradiation, nor a previous history of
a benign or malignant lesion in the breast. No screening mammography had
been performed by that time. Physical examination revealed an
ill-defined, firm, mobile, and nontender six cm mass in the central and
lateral portion of the breast, behind the nipple-areola complex.
The physical exam of the axillary area and contralateral breast were
unremarkable.
The mammography and ultrasonography revealed an irregular bulky mass
with a lobulated border in the lateral part of the right breast. On MRI
study, there was a 4 cm mass in the lateral part of the right breast
with a high signal intensity at the periphery of the tumor.
The initial Core needle biopsy findings were compatible with
extra-skeletal osteosarcoma which was confirmed by the second opinion
based on the exclusion of the phyllodes tumor and metaplastic carcinoma
along with performing IHC that was strongly positive for vimentin with
30-35% proliferative activity (Ki 67) and nonreactive for Pan-Ck.
There was no evidence of distant metastasis based on liver function
test, chest and abdominal CT, and bone scan.
As our institute routine, the patient was discussed in a
multidisciplinary team and a simple mastectomy followed by Adriamycin
and Ifosfamide regimen of chemotherapy and 50 Gy radiation was planned
for her.
The patient underwent a simple mastectomy. Although the tumor was not
grossly fixed to the underlying chest wall structures, the deep margin
was too close to the fascia of the pectoralis muscle. Therefore, a thin
discoid shape layer of pectoral muscle just beneath the tumor lodge was
resected en-bloc with the rest of the specimen. Additionally, four
enlarged lymph nodes were resected as a caution. All parts of the
specimen were sectioned into 4 μm thick and were stained with
hematoxylin and eosin as well as Elastica van Gieson. Histological
evaluation of the surgical specimen showed atypical tumor cells that
were embedded in extensive ossified vermiform plexus of osteoid, bearing
necrosis, and autolysis. There was no chondroid differentiation nor
evidence of phyllodes tumor or metaplastic carcinoma. The histological
result was confirmed by IHC with the avidin-biotin-peroxidase complex
method leading to negativity for Pan-CK and CAM 5.2 as well as strong
positivity for Vimentin in addition to 30-35% proliferative activity
(Ki67). All margins and lymph nodes were free of tumor. It is worth
mentioning that all the histological evaluations have been done by two
expert pathologists in the field of sarcoma separately.
After recovery, the patient underwent chemotherapy with the mentioned
regimen for five cycles and subsequently received radiotherapy 50 Gy.
The treatment plan finished uneventfully last month.