METHODS
Patients who visited our clinic were retrospectively evaluated.
RESULTS
All patients were females and the median age was 42 (29?60) years. The evaluated tumor sites were observed
in the body/trunk in one patient, at the hip in two, and at the proximal lower extremity in two. Surgical
excision was done in all of them as initial treatment. Re-excision was needed in three patients. One
of the patients underwent punch biopsy for diagnosis and surgical removal of the tumor with a negative
surgical margin. One of the patients underwent radiotherapy. The median follow-up time was 10 (6?26)
months. During the median follow-up, there was no local recurrence or metastasis.
CONCLUSION
As initial treatment, it is important to surgically remove tumors that had no distant metastasis. Positive
or near surgical margins should be resected again. If a negative surgical margin cannot be achieved,
radiotherapy should be used as the treatment. Imatinib mesylate is used for treatment in unresectable,
recurrent, and/or metastatic tumors.
Keywords: Dermatofibrosarcoma protuberans; imatinib; radiotherapy; surgery
DFSP, a fibrohistiocytic tumor characterized by skin
and subcutaneous protuberant growth pattern, has
painless, slow-growing, dark red or blue plaques. Over
time, tumor enlargement and protuberant or ulcerative
appearance occurs. Protuberant nodules can infiltrate
subcutaneous tissue, fascia, muscles, and even bone.[
DFSP is characterized by translocation between
chromosomes 17 and 22 [t (17; 22) (q22; q13)], indicating
platelet-derived growth factor receptor beta (PDG-FRB) overexpression. Patients with this translocation
can be treated with imatinib mesylate.[
It is important to surgically remove tumors with no
metastasis during the initial treatment. If the tumor is
not completely removed, the recurrence rate is high.
Positive or near surgical margins should be resected
again.[
This study aimed to review the literature for DFSP
cases.
Case 1: A 60-year-old female patient with complaint
of blue-violet painless swelling on the right side of her waist for about 6 months presented to the clinic. Her
past history revealed that 28 months ago, she had a surgical
intervention for the complaint of swelling at the
same site, which was pathologically diagnosed as fibroma.
There was no property in her family history. The
patient"s excised tumor measured 5×2.5×5 cm and was
microscopically infiltrated with subcutaneous fat tissue
starting just below the multilamellar epithelium and
high-cell tumor with a cellularity showing storiform
pattern was observed (Fig.
Case 2: A 60-year-old woman presented with painless swelling on the side of the right thigh for about 7 months. The patient"s history and family history were unremarkable. The excised tumor of the patient measured 2.1×1.5×1.3 cm. Microscopic examination revealed a tumor showing infiltration in the fatty tissue with ulcerations in the multilamellar squamous epithelium. Tumor cells were arranged in a storiform pattern that crossed each other. Cells were spindle shaped with epithelioid character with hyperchromatic nucleus and narrow cytoplasm. Tumor cells were positive for CD34 and vimentin, negative for factor XIIIa, S100, HMB45, and desmin in IHC staining. Ki-67 proliferation index was evaluated as 8%. Radiotherapy was performed because it was thought that surgery could not be achieved with re-excision for the patient with positive surgical margin. Patient had no metastasis and was followed up.
Case 3: A 42-year-old woman who had a swelling on her right hip for about 20 years was suffering from the swelling"s changing color and enlargements for the past year. She has no other feature, except for the solitary nodule in the thyroid. Her parents had died due to lung cancer. Her brother had thyroid cancer. The excised tumor measured 2×1×1.2 cm and on microscopic examination revealed infiltration in the fatty tissue that formed ulceration in the multilamellar epithelium. Tumor cells were arranged in a storiform pattern that crossed each other. Cells were spindle shaped with epithelioid character with hyperchromatic nucleus and narrow cytoplasm. Tumor cells were CD34 positive in the IHC stain. Ki-67 proliferation index was evaluated as 2%. Re-excision was performed in the patient with a positive surgical margin. Patient had no metastasis and was followed up after successful surgery with negative surgical margin.
Case 4: A 44-year-old woman with a history of swelling in the right and left thighs for about 6 years was suffering from the swelling"s changing color and enlargements for the last 2 months, especially in the left thigh. The patient had a history of epilepsy. Her family history was unremarkable. A well-limited fibrohistiocytic benign tumor dermatofibroma in the dermis excised from the right thigh and a 1.5×1×1-cm tumor in the left thigh was evaluated as DFSP with infiltrative appearance of the dermis, a storiform pattern, and spindle cells. IHC staining showed CD34 positive and factor XIIIa negative. Re-excision was performed with a negative surgical margin, and after surgery, the patient had no metastasis and was followed up.
Case 5: A 29-year-old woman who had a swelling on
her right hip for about 3 years was suffering from the
swelling"s changing color for the last 3 months. There
was a history of Familial Mediterranean Fever. Her
family history was unremarkable. Punch biopsy was
done. Spindle cellular tumor was found in the storiform
pattern, extending from the submucosal fatty
tissue, starting from the multilamellar flat epithelium.
The IHC stain was positive for CD34 and vimentin and
negative for factor XIIIa and S100. Surgical margin
negativity was ensured and tumor was removed with
the largest diameter was 0.7×0.5×0.5 cm. The patient
had no metastasis and was followed up (Table
This tumor may be misdiagnosed as a result of inappropriate
tissue sampling or superficial biopsy. Deep
subcutaneous layer punch or incisional biopsy is recommended
for adequate tissue sampling and complete
pathologic evaluation.[
In fact, dermatofibroma differs from DFSP at times. In
such cases CD34, factor XIIIa, nestin, apolipoprotein
D, cathepsin staining are useful as IHC. CD34 positivity
and factor XIIIa negativity was seen in almost all
cases with DFSP diagnosis. Ki-67 is used as a proliferation
marker.[
Initial treatment is surgical removal of the lesion. The
purpose of the surgery is to remove the tumor by obtaining
a negative surgical margin. Re-excision is recommended
if surgical margin is positive.[
Radiotherapy is also used as a primary therapeutic
modality, as well as adjuvant therapy after surgery. A
10-year disease-free survival rate after surgery and adjuvant
radiotherapy was 93% in a single-center retrospective
study. Postoperative radiotherapy is usually
preferred if there is no positive surgical margin and no
re-excision is possible. Adjuvant radiotherapy is not required
if a negative surgical margin is obtained.[
DFSP is characterized by translocation between chromosomes
17 and 22 [t (17; 22) (q22; q13)]. This translocation
results in PDGFRB overexpression. Imatinib
mesylate, an inhibitor of protein tyrosine kinase in
DFSP treatment, has been approved for adults in unresectable,
recurrent and/or metastatic DFSP. If this
translocation is absent in the tumor, it is unresponsive
to imatinib treatment.[
Disclosures Statement
Ethics Committee Approval: This study was conducted inaccordance
with local ethical rules.
Peer-review: Externally peer-reviewed.
Conflict of Interest: None declared.
Authorship contributions: Concept - Ü. Ü; Design - Ü. Ü, S. E. D; Supervision - Ü. Ü, N. K; Materials - Ü. Ü, S. E. D, F. Y; Data collection &/or processing - Ü. Ü, N. K; Analysis and/or interpretation - Ü. Ü; Literature search - Ü. Ü, T. T. D; Writing - Ü. Ü, T. T. D; Critical review - Ü. Ü, F. Y.