Dermatofibrosarcoma protuberans (DFSP) is an uncommon skin cancer that most commonly occurs on the trunk and extremities. DFSP of the breast has rarely been reported, and then is almost always of small size. We report a case of rapid-growing DFSP of the breast with abscess formation mimicking breast cancer, and also make a review of related literature

Cheng-Li Chin

Chia-Sheng Yan

Chien-Feng Li

Ding-Ping Sun

Han-Kun Chen

Ming-Jenn Chen

Wen-Ching Wang

Yih-Huei Uen

Yu-Feng Tian

隆突性皮膚纖維肉瘤是一種罕見的皮膚癌，一般常見是發生在軀幹和四肢。而發生在乳房的案例更是少見報導，而且幾乎是以體積小的腫瘤呈現。我們報告一名快速增長的隆突性皮膚纖維肉瘤而在型態上類似巨型乳癌合併膿瘍的個案，並和一系列的相關文獻作一比較。

台灣癌症醫學雜誌

Huge Dermatofibrosarcoma Protuberans Mimicking a Breast Malignant Tumor with Abscess

Journal of Cancer Research and Practice

Directory of Open Access Journals

AbstractDermatofibrosarcoma protuberans (DFSP) is an uncommon skin cancer that most commonly occurs on the trunk and extremities. DFSP of the breast has rarely been reported, and then is almost always of small size. We report a case of rapid-growing DFSP of the breast with abscess formation mimicking breast cancer, and also make a review of related literature

Chen, Han-Kun

Li, Chien-Feng

Uen, Yih-Huei

Tian, Yu-Feng

Chen, Ming-Jenn

Yan, Chia-Sheng

Wang, Wen-Ching

Chin, Cheng-Li

Sun, Ding-Ping

Elsevier - Publisher Connector 

 Case Report  
Huge Dermatofibrosarcoma Protuberans Mimicking a Breast 
Malignant Tumor with Abscess 
Han-Kun Chen1, Chien-Feng Li2, Yih-Huei Uen1, Yu-Feng Tian3, Ming-Jenn Chen3, Chia-Sheng Yan3, 
Wen-Ching Wang3, Cheng-Li Chin3, Ding-Ping Sun3* 
1Departments of General Surgery, Chaili Chi-Mei Medical Hospital, Tainan, Taiwan 
2Department of Pathology, Chi-Mei Foundation Medical Center, Tainan, Taiwan 
3Departments of General Surgery, Chi-Mei Foundation Medical Center, Tainan, Taiwan 
Abstract. 
Dermatofibrosarcoma protuberans (DFSP) is an uncommon skin cancer that most com-
monly occurs on the trunk and extremities. DFSP of the breast has rarely been reported, and 
then is almost always of small size. We report a case of rapid-growing DFSP of the breast with 
abscess formation mimicking breast cancer, and also make a review of related literature. 
 
Keywords : dermatofibrosarcoma protuberans, breast, fibrosarcomatous transformation 
病例報告  
巨大隆突性皮膚纖維肉瘤臨床上擬似乳房惡性腫瘤合併膿瘍 
陳漢坤 1 李健逢 2 溫義輝 1 田宇峯 3 陳明鎮 3 顏家聖 3 王文慶 3 鄭立勤 3 孫定平 3* 
1財團法人佳里奇美醫院 一般及消化系外科 
2財團法人奇美醫院 病理科 
3財團法人奇美醫院 一般及消化系外科 
中文摘要 
  隆突性皮膚纖維肉瘤是一種罕見的皮膚癌，一般常見是發生在軀幹和四肢。而發生
在乳房的案例更是少見報導，而且幾乎是以體積小的腫瘤呈現。我們報告一名快速增長
的隆突性皮膚纖維肉瘤而在型態上類似巨型乳癌合併膿瘍的個案，並和一系列的相關文
獻作一比較。 
 
關鍵字: 隆突性皮膚纖維肉瘤、乳房、纖維肉瘤轉化 
INTRODUCTION 
Dermatofibrosarcoma protuberans (DFSP) is a ra-
re cutaneous soft tissue sarcoma, usually appearing on 
the torso, arms, legs, head, and neck. The size is 
commonly limited to less than three centimeters [1,2]. 
DFSP of the breast has rarely been reported. We re-
port one case of a huge breast DFSP of more than 20 
centimeters in size that presented as a malignant breast 
tumor and will review the literature related to DFSP of 
the breast. 
 
 
journal homepage:www.cos.org.tw/web/index.asp
台灣癌症醫誌 (J. Cancer Res. Pract.) 1(3), 267-272, 2014 DOI: 10.6323/JCRP.2014.1.3.12
Open access under CC BY-NC-ND license.
 CASE REPORT 
A 45-year-old premenopausal woman presented 
with no significant prior medical history. She reported 
the existence of a non-tender mass lesion in her right 
breast for two years. She tried to ignore it, but the 
mass continued to increase in size over time. About 
three months ago, she began to feel intermittent right 
breast pain. She asked for medical assistance due to 
fever, diffuse painful sensations in the right breast, 
and pus discharge from the skin ulcer. Physical ex-
amination revealed a huge tender mass about 20 cen-
timeters (cm) in size with a skin ulcer on admission. 
Laboratory studies showed leukocytosis (white blood 
cell 12100/uL), high serum C-reactive protein (> 250 
mg/dl), and normal tumor marker (carcinoembryonic 
antigen, 1.67 ng/ml). Initial treatment included oxacil-
lin 8 g/day intravenous drug infusion and debridement 
of the abscess from the breast ulcer. The pathology 
only showed necrotizing inflammation and the culture 
showed the Staphylococcus species. The breast so-
nography revealed a huge heterogenic echoic mass of 
more than 20 cm (Figure 1). A core-needle biopsy was 
performed, but only an abscess was discovered. She 
still had a low-grade fever and persistent mastalgia 
after medical treatment. 
Then the suspicion of a huge tumor of unknown 
nature exhibiting an uncontrolled inflammatory pro-
cess, a modified radical mastectomy with split thick-
ness skin graft was performed. Intraoperatively, we 
discovered a 23-cm soft tissue mass occupying the 
entire breast and a residual abscess within the tumor 
near the previous debridement site. Final pathology 
revealed dermatofibrosarcoma protuberans with fi-
brosarcomatous transformation. Large areas of tumor  
 
 
 
 
 
 
 
 
 
 
 
Figure 1. The breast sonography revealed a huge het-
erogenic echoic mass occupying the whole 
right breast 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 2. H&E, dermatofibrosarcoma protuberans, 
40X: The figure shows a well-defined 
dermal tumor revealing a pushing border 
 
 
necrosis could also be discerned. The lymph nodes 
and section margins were free of tumor involvement. 
Postoperative cancer systemic work-up revealed no 
definite evidence of metastases in the abdominal so-
nography and whole body bone scan. This patient re-
ceived systemic chemotherapy with 3 cycles of Epiru-
bicin 80 mg and Endoxan 1200 mg. She made an un-
eventful recovery, and was free of disease one year 
postoperatively. 
 
*Corresponding author: Ding-Ping Sun M.D. 
*通訊作者：孫定平醫師 
Tel: +886-6-2812811 
Fax: +886-6-2828982 
E-mail: merle.a999@gmail.com 
268 H. K. Chen et al./JCRP 1(2014) 267-272
  
 
 
 
 
 
 
 
 
 
 
Figure 3. H&E and CD34 (inset), dermatofibrosar-
coma protuberans, 200X: This tumor is 
mainly composed of hyperchromatic and 
monotonous spindle cells arranged in 
compact storiform patterns supported by a 
rich vasculature. Immunohistochemically, 
these tumor cells are diffusely and strong-
ly positive for CD34 (inset) 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 4. H&E, dermatofibrosarcoma protuberans, 
400X: About 30% of the tumor demon-
strates enlarged nuclei and a herringbone 
pattern with elevated mitotic activity indi-
cating fibrosarcomatous transformation 
 
 
PATHOLOGIC FINDINGS 
Histologically, the tumor extended from the der-
mis to the deeper fibroadipose tissue (Figure 2). The 
tumor was mainly composed of hyperchromatic and 
monotonous spindle cells arranged in compact stori-
form patterns supported by a rich vasculature. Large 
areas of tumor necrosis could also be discerned. 
Around 20% of the tumor cells demonstrated enlarged 
nuclei and a herringbone pattern with elevated mitotic 
activity indicating fibrosarcomatous transformation 
(Figure 3). 
From the immunohistochemical study (Figure 3), 
we learned that these tumor cells were positive for 
CD34. The Ki-67 labeling index was markedly ele-
vated (at 20%) at the fibrosarcomatous transformation 
area (Figure 4). The final pathology was then dermato-
fibrosarcoma protuberans with fibrosarcomatous trans-
formation, without nodal metastasis. 
 
DISCUSSION 
Dermatofibrosarcoma protuberans (DFSP) was 
first described by Darier in 1924 [3]. It is an uncom-
mon cutaneous sarcoma that constitutes less than 1% 
of all sarcomas [1]. It originates in the dermis and has 
an aggressive invasive tendency [4]. DFSP presents as 
a slow-growing tumor and its symptoms are long- 
lasting [5,6]. Grossly, it usually presents as painless, 
irregular nodules or plaques varying in color from 
flesh to reddish brown and occasionally mimics he-
mangioma [1,5]. 
DFSP most commonly occurs on the skin of the 
trunk in approximately 42% of cases, while in 18% of 
cases it involves the lower extremities and hips, and in 
15% affect the head and neck [5]. Tumors presenting 
as breast tumors are rare. A literature search for DFSP 
of the breast revealed several cases, the clinical details 
of which are listed in Table 1. In most of these cases, 
the tumor size is usually limited to three centimeters, 
and they presented as a tumor slowly growing across 
several months up to more than ten years. 
Complete surgical resection is the mainstay of 
therapy for DFSP. Unfortunately, even when the tu-
mor has been resected with good safe margins, there 
still has been a high recurrence rate of up to 60% after  
H. K. Chen et al./JCRP 1(2014) 267-272 269
  
T
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jo
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na
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270 H. K. Chen et al./JCRP 1(2014) 267-272
 surgical resections, with substantial morbidity being 
reported in the past [5]. In our recent review, many 
authors still mentioned the same opinion that com-
pletive surgical resection with wide, pathologically 
negative margins of at least 2-3 cm is the optimal 
treatment option for primary or recurrent DFSP [7]. 
Distal metastasis is very rare. Metastatic disease is 
usually preceded by multiple recurrences. The lung is 
the most predominant site of metastasis via hematog-
enous spread. Regional lymph nodes are rarely in-
volved [7]. 
Some principal reports suggest postoperative radi-
ation to reduce the risk of local recurrence [4,8]. 
However, there was also a report of radiation therapy 
causing chronic radiation dermatitis as an inducer of 
DFSP [9,10]. DFSP is associated with t(17,22) (22; 
q13) translocation, which generates a Col1/PDGF 
(PDGF: platelet-derived growth factor) fusion gene 
and constitutively activates the PDGF receptor 
(PDGFR) [11]. Recent reports mention that imatinib, 
which inhibits the PDGF receptor, and can be used as 
the target therapy and neoadjuvant therapy [12-14]. 
 
CONCLUSIONS 
Dermatofibrosarcoma protuberans is a very rare 
malignant soft tissue sarcoma that rare occurs in the 
breast. Most DFSP grows slowly, but it can occasion-
ally enlarge rapidly due to the inflammatory process. 
Complete surgical resection with safe margins of at 
least 2-3 cm is currently an optimal treatment, but 
there is a very high recurrence rate. The radiation 
therapy for the postoperative treatment and imatinib 
for the target or neoadjuvant therapy need to be con-
sidered in patients with positive surgical margins and 
unresectable or metastatic tumors. 
 
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Huge Dermatofibrosarcoma Protuberans Mimicking a Breast Malignant Tumor with Abscess 

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Huge Dermatofibrosarcoma Protuberans Mimicking a Breast Malignant Tumor with Abscess

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