Immunohistochemical characterization of dermatofibrosarcoma protuberans with practical applications for diagnosis and treatment

Dermatofibrosarcoma Protuberans of Face: A Rare Entity and Review of Literature

Dermatofibrosarcoma protuberans is a very rare tumour that accounts for less than 0.1% of all malignant neoplasms. It is a locally aggressive tumour with high recurrence rate. Head and neck involvement is very uncommon and hence diverse treatment protocols have been recommended for its management in the currently available literature. We present a case of dermatofibrosarcoma protuberans over the lower part of right cheek in a middle aged male, which was successfully treated with wide local excision and reconstruction along with post-op radiotherapy. The patient was followed-up for 18 months with no recurrence. Prompt and accurate diagnosis along with multidisciplinary treatment is crucial for optimal management of this rare tumor. The optimal treatment option is surgical resection with wide margins along with adjuvant radiotherapy, which leads to better outcomes even in patients with positive surgical margins. Larger clinical trials with Imatinib will firmly establish its chemotherapeutic role in its management. Lifelong regular follow-up is essential for early detection of tumor.

Cutaneous soft tissue sarcomas: survival-related factors

Cutaneous sarcomas are a heterogeneous group of rare mesenchymal neoplasms representing less than 1% of malignant tumors. Histology report remains the cornerstone for the diagnosis of these tumors. The most important clinicopathologic parameters related to prognosis include larger tumor size, high mitotic index, head and neck location, p53 mutations, depth of infiltration and histological grade, vascular and perineural invasion as well as the surgical margins status. Applying advanced biopsy techniques might offer more precise assessment of surgical margins, which constitutes a significant precondition for the management of these tumors. The management of cutaneous soft tissue sarcomas requires a multidisciplinary approach. Surgery remains the standard treatment, nonetheless adjuvant therapy may be required, consisting of radiotherapy, chemotherapy, and molecular targeted therapies to improve treatment outcomes. The role of molecular profiling in the treatment of uncontrolled disease is promising, but it may be offered to a relatively small proportion of patients and its use is still considered experimental in this setting. Due to the rarity of the disease, there is a need for knowledge and experience to be shared, pooled, organized and rationalized so that recent developments in medical science can have a major impact on the disease course. Multicenter clinical trials are needed to improve the care of patients with cutaneous sarcomas.

Dermatofibrosarcoma Protuberans Mimicking Primary Breast Neoplasm: A case report and literature review

Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing mesenchymal neoplasm of the dermis and subcutaneous tissues that has a low-to intermediate-grade malignancy. DFSP commonly involves the trunk and extremities, and very rarely the breast skin, mimicking a primary breast neoplasm with few reported cases in the literature. We report a 35-year old female patient who was referred to the Royal Hospital, Muscat, Oman in 2017, with a two-year history of a slow growing left breast lump. Assessment of the breasts with mammography revealed a lobulated lesion in the left-upper-inner quadrant with neither microcalcification nor architectural distortion, mimicking a benign lesion. However, on ultrasound, the lesion had suspicious features with increased vascularity and hence, it was categorised as breast imaging reporting and data system (BIRAD) IV. The patient underwent left breast wide local excision and the histopathological diagnosis was dermatofibrosarcoma protuberans.

Unmasking dermatofibrosarcoma protuberans: Case report of an atypical presentation complicated by post-surgical excision

INTRODUCTION

Dermatofibrosarcoma Protuberans (DFSP) is a rare type of malignant tumor of the cutaneous soft tissue that typically involves the dermis and surrounding structures. The typical clinical presentation involves an asymptomatic, slowly enlarging, indurated plaque, usually found on the trunk.

PRESENTATION OF CASE

Here we present an atypical presentation of DFSP in a patient with a recurrent mass that was initially diagnosed as a lipoma, with supporting literature and clinical considerations for post-surgical management DISCUSSION: In its earlier stages, DFSP can mimic other benign or malignant dermatological pathologies, which can complicate diagnosis purely via history and physical exam. Atypical features such as prior surgical management, morphology, and location can complicate the clinical diagnosis of DFSP. Immunohistochemistry is often required for definitive diagnosis as DFSP is CD34+ and is histologically described as spindle-cells in whorled or storiform pattern, with uniform, small elongated cells.

CONCLUSION

DFSP is a rare tumor of the skin and subcutaneous tissue. Though it commonly presents with induration, skin discoloration, and telangiectasias, it is important to keep DFSP as a differential in new masses found on previous surgical sites, especially if the previous mass had a possibility of recurrence.

Ophthalmologic aspects of Dermatofibrosarcoma Protuberans: A systematic review in the context of a rare case of primary orbital involvement

OBJECTIVE

To provide a systematic review on ophthalmologic presentations of dermatofibrosarcoma protuberans (DFSP) in conjunction with a case report of primary orbital involvement by this tumor.

METHODS

A thorough electronic search on PubMed, Medline, Scopus, EMBASE and web of science databases was performed. All available data from reported cases along with our described case were extracted and analyzed.

RESULTS

We describe a 66-year-old male with primary orbital DFSP who was managed by total excision of the tumor without recurrence after 18 months of follow-up. In the literature, 14 studies reporting 15 cases were identified and reviewed. Our review topics included epidemiology, clinical presentations, pathologic features, differential diagnosis, imaging, treatment and prognosis.

CONCLUSION

Rarely, but crucially, ophthalmologists may encounter DFSP in the orbital or periorbital area. They should be familiar with the pathologic nature and treatment options for this tumor. This diagnosis should be kept in mind when approaching a case with a non-tender, nodular, firm, mass or more rarely an indenting orbital mass.

Dermatofibrosarcoma protuberans: A rare and devastating tumor of the vulva

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Biopsies of a large mass are prone to sampling errors and may lead to an incorrect diagnosis.

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MRI imaging of vulvar tumors can aid in surgical planning.

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Large sarcomas of the vulva require a multi-disciplinary approach.

Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a rare superficial soft tissue sarcoma. Its rarity precludes large prospective studies. Clinical diagnosis requires an high index of suspicion. Effective management requires an appreciation of tumor biology and the nature of the characteristic infiltrative growth pattern. DFSP tends to recur locally, with a low risk of dissemination. Aggressive surgical resection with widely negative margins is essential to management. Radiotherapy may be indicated in special circumstances. Understanding the molecular pathogenesis has resulted in use of tyrosine kinase inhibitor therapy for patients with locally advanced disease or in metastatic disease. DFSP patients require long-term follow-up.

Myxoid Dermatofibrosarcoma Protuberans of the Vulva: Case Report of a Rare Variant in an Unusual Location, With Unusual Morphologic and Immunohistochemical Features

Dermatofibrosarcoma protuberans (DFSP) is a low-to-intermediate grade infiltrative dermal neoplasm with a predilection for the trunk and extremities. DFSP in the vulvar region is extremely rare, with fewer than 50 cases reported to date in the literature. The histologic diagnosis of this neoplasm is facilitated by the characteristic storiform pattern of spindle cells with infiltration into the subcutaneous fat in a "honeycomb" pattern. However, morphologic variants including the very rare myxoid DFSP have been recognized that pose significant diagnostic difficulties, especially when they occur at unusual sites. The authors describe a case of myxoid DFSP of the vulva in a 44-year-old woman that was initially misdiagnosed as a neurofibroma. Subsequent excision led to significant challenges in diagnosis due to lack of typical morphology and unusual immunohistochemical staining pattern. Presence of peripheral adipose tissue trapping was noted focally that led to suspicion of DFSP. The diagnosis was confirmed by the detection of the characteristic COL1A1/PDGFB fusion transcript by reverse-transcription polymerase chain reaction. This case underscores the diagnostic challenge presented by variants of DFSP presenting in unusual locations and the value of molecular confirmation of the diagnosis.

A rare case of dermatofibrosarcoma protuberans of the forefoot

Dermatofibrosarcoma protuberans is an extremely rare, potentially malignant tumor type that usually presents on the trunk or proximal extremities. The clinical presentation includes a gradually enlarging painless plaque-like or nodular lesion of the skin with surrounding red to blue discoloration. The diagnosis is based on clinical presentation, computed tomography or magnetic resonance imaging, and biopsy with histologic analysis. An early and timely diagnosis improves chances of complete surgical resection thus improving prognosis. Herein, we present a rare case of dermatofibrosarcoma protuberans with the hopes that its addition to the literature will aid in the earlier recognition of future patients and help prevent this potentially curable disease from becoming deadly.

Dermatofibrosarcoma Protuberans: A Rare Malignancy of the Breast

Dermatofibrosarcoma protuberans (DFSP) of the breast is a rare skin cancer with only a few cases reported in the literature. It corresponds to approximately 1% of all soft tissue sarcomas and to less than 0.1% of all malignancies with annual incidence of 0.8-4.5 cases per million. DFSP usually affects young and middle-aged adults and it can affect any site, but most commonly the trunk and extremities. This tumor arises from the deep dermis and subcutaneous tissues and is usually locally aggressive, but rarely metastasizes. Surgery including wide local excision with free margins remains the main modality of treatment. We report a case in a 28-year-old Omani woman who presented with a right breast lump to a local secondary hospital. She was offered excision biopsy of the lump and the histology came as DFSP with involved margins. The patient was then referred to the Breast Unit at the Royal Hospital where she was reviewed by multidisciplinary team including breast surgeons, oncologists, radiation oncologists, pathologists, and breast radiologists. Her laboratory and radiological investigations did not show any signs of distal metastasis and breast ultrasound did not reveal any residual breast lesions. We performed a wide re-excision of the previous surgical scar with the underlying breast tissues down to the level of the pectoral fascia followed by treatment with radiotherapy. The final histology report showed the presence of a 4×5mm residual tumor, and all resection margins were tumor-free. At six months follow-up, she had no signs of local recurrence. We publish this case report because of its rarity.

Dermatofibrosarcoma protuberans with pit-like lesions: A case report and literature review

The present study describes a case of pit-like dermatofibrosarcoma protuberans (DFSP) with the clinical manifestations, histopathological features and criteria for diagnosis. The study also reviews the relevant literature in order to raise awareness among dermatologists with regard to the specific behavior of DFSP. A 27-year-old female presented with subcutaneous nodules on the left side of the neck that had been apparent for 5 years and which had gradually begun caving in during the last year. Histopathological examination revealed that the tumor was composed of a large number of spindle cells arranged in a whirlpool-like pattern. Immunohistochemical studies revealed positive staining for cluster of differentiation 34, vimentin and lysozyme, which could be used as diagnostic markers of DFSP. The patient was finally diagnosed with DFSP by pathological and immunohistochemical analyses. The DFSP was treated with an extended resection followed by adjacent skin repair. The patient responded well and no relapse occurred during the 8-month clinical follow-up. Thus, the current study describes a unique pit-like clinical manifestation of DFSP with typical immunohistochemical and pathological features. In addition, histopathological examination revealed a downward depression in the epidermis. Therefore, histopathological examination should be considered as an essential diagnostic tool for DFSP.

Fluorescence in situ hybridization analysis is a helpful test for the diagnosis of dermatofibrosarcoma protuberans

Cytogenetically, most dermatofibrosarcoma protuberans are characterized by chromosomal rearrangements resulting in the collagen type-1 alpha 1 (COL1A1)-platelet-derived growth factor β (PDGFB) fusion gene. This abnormality can be detected by fluorescence in situ hybridization (FISH) analysis in routine practice. The aim of this study was to evaluate the role of the FISH analysis in the diagnosis of dermatofibrosarcoma protuberans. A FISH analysis was prospectively and systematically performed on a series of 448 consecutive tumor specimens. All cases were reviewed by two independent pathologists and classified in three categories according to the probability of a DFSP diagnosis before molecular analyses. Cases were classified as certain when dermatofibrosarcoma protuberans was the only possible diagnosis. Those cases for which dermatofibrosarcoma protuberans remained the first diagnosis, but other differential diagnosis existed, were regarded as probable. When dermatofibrosarcoma protuberans was considered a differential diagnosis, they were labeled as possible. The final diagnosis was supported by clinicopathological findings and results of FISH analyses. Immunohistochemical analysis of CD34 was systematically performed, and additional markers when necessary. The cases (n=37) with a non-interpretable FISH were excluded. For the 185 certain tumors specimens: 178 (96%) FISH analyses showed a PDGFB/COL1A1 rearrangement, 7 (4%) were negative. For the 114 probable tumors specimens: 104 (91%) FISH analyses were positive and 10 (9%) were negative leading to a new diagnosis in 8 cases. For the 112 possible cases: 91 (81%) FISH analyses were negative and 21 (19%) were positive. Of the 21 cases, initial diagnoses included unclassified sarcoma, myxofibrosarcoma, dermatofibroma, reactive lesion, solitary fibrous tumor, perineurioma, benign nerve sheath tumor, and undifferentiated spindle cell tumor without malignant evidence. FISH analysis has been helpful for confirming the diagnosis of dermatofibrosarcoma protuberans in 25% (104/411) of cases and necessary for the diagnosis of dermatofibrosarcoma protuberans in 5% (21/411) of cases.

Imaging findings of head and neck dermatofibrosarcoma protuberans

BACKGROUND AND PURPOSE

Dermatofibrosarcoma protuberans is a rare, locally aggressive sarcoma of the skin in children and adults, usually involving the trunk and extremities and less commonly the head and neck. Despite clinical reports in the literature on the management of dermatofibrosarcoma protuberans, there are limited articles describing its imaging features.

MATERIALS AND METHODS

We retrospectively reviewed the demographics and imaging findings in all 24 patients with pathologically proven dermatofibrosarcoma protuberans of the head and neck seen at a tertiary cancer center between 2001 and 2010.

RESULTS

Twenty-two of the 24 lesions were nodular and well circumscribed; 19 of the 24 were located on the scalp. On imaging, all 24 lesions involved subcutaneous tissues. The lesions ranged in size from 0.6-9.5 cm (mean, 3.7 cm; standard deviation, 2.3 cm). Twelve lesions involved the soft tissues either at or extending directly to the midline. Thirteen lesions were associated with bulging of the skin surface. Fourteen lesions were imaged with CT and 14 with MR imaging. Whereas variable enhancement patterns were noted on CT and MR imaging, dermatofibrosarcoma protuberans was usually T2-hyperintense and demonstrated marked enhancement. None of the lesions was associated with bone invasion, perineural spread, or nodal/distant metastasis.

CONCLUSIONS

Knowledge of the imaging characteristics of dermatofibrosarcoma protuberans may alert neuroradiologists to include dermatofibrosarcoma protuberans in the differential diagnosis of lesions about the head and neck with similar imaging characteristics.

Molecularly targeted therapies for nonmelanoma skin cancers

Over the past two decades, advances in the fields of cancer genetics and molecular biology have elucidated molecular pathways that cause numerous cutaneous malignancies. This in turn has spurred the rational design of molecularly targeted therapies. In this review, we discuss the molecular pathways critical to the development of nonmelanoma skin cancers and the novel pharmacologic agents that target them. Included is a review of vismodegib for basal cell carcinoma, cetuximab for squamous cell carcinomas, imatinib for dermatofibrosarcoma protuberans, and sirolimus for Kaposi's sarcoma.

Dermatofibrosarcoma protuberans (DFSP) successfully treated with sorafenib: case report

DFSP is a locally invasive, slow-growing tumor of the subcutaneous tissue that rarely metastasizes but recurs frequently after surgical excision. We report herein a case of highly recurrent, locally invasive DFSP that failed both postoperative radiation therapy and complete trial of Imatinib, but was successfully treated with Sorafenib, which showed unprecedented response.

Soft tissue tumors of the anorectum: rare, complex and misunderstood

Anorectal soft tissue tumors are uncommon and often present both diagnostic and therapeutic challenges. Although many of these tumors are identified with imaging performed for unrelated reasons, most present with nonspecific symptoms that can lead to a delay in diagnosis. Historically, radical surgery (abdominoperineal resection) has been the mainstay of treatment for both benign and malignant anorectal soft tissue tumors. However, a lack of proven benefit in benign disease along with changes in technology has called this practice into question. In addition, the role of radiation and/or chemotherapy remains controversial. In this manuscript, we review the history and current status of anorectal soft tissue tumor management, with a particular focus on challenges in optimizing survival.

Primary dermatofibrosarcoma protuberans of orbit--a rare entity

Primary Dermatofibrosarcoma Protuberance (DFSP) is a rare neoplasm of dermal origin. Though it is a locally aggressive tumor with high recurrence rate, however distant metastasis can also occur. Orbital DFSP is an uncommon phenomenon. It has been reported due to distant metastasis or invasion from adjacent structures but Primary Orbital DFSP is a unique entity in itself. Herein we report a rare case of primary DFSP of the orbit in a 70-year- old lady who underwent orbital exenteration. Histopathology examination (HPE) revealed spindle cells arranged in storiform pattern and immunohistochemistry (IHC) revealed CD34 positive and S100 negative.

Computed tomographic and pathological findings of dermatofibrosarcoma protuberans

OBJECTIVE

The aim of the study was to investigate the computed tomographic (CT) and pathological findings of dermatofibrosarcoma protuberans to improve the awareness and understanding of the tumors from aspect of CT images.

METHODS

The CT findings of 16 cases (17 tumors) with dermatofibrosarcoma protuberans confirmed by pathological findings were retrospectively selected. Fourteen cases were primary dermatofibrosarcoma protuberans, 2 cases were recurrent tumors. Thirteen patients had CT plain and enhanced scans, 1 patient had direct enhanced CT scan, 2 patients had only unenhanced scan. Images of the tumors were analyzed and compared with pathological results.

RESULTS

Of the 16 cases (17 tumors total), 9 cases were on the trunk, 7 cases were on the head and the neck; 15 cases appeared as solitary isohypodense, ovoid, or round mass at the cutaneous and subcutaneous tissue, 1 case demonstrated 2 isodense masses on unenhanced CT images. The mean diameter of tumors was 4.0 cm, and the depth was 1.7 cm. The margin was well defined (n = 15 [88.2%]) or ill defined (n = 2 [11.8%]). Fifteen tumors revealed moderate or marked homogeneous (n = 12 [80%], smaller lesion, diameter <5 cm) or heterogeneous (n = 3 [20%], larger lesion, diameter ≥5 cm) enhancement on enhanced CT with intratumoral nonenhancement areas, which indicated intratumoral necrotic and cystic degeneration areas. No calcifications and metastasis were found. The histological examinations revealed large amounts of uniform spindle cells, which were arranged in "storiform" pattern. Immunohistochemical analysis revealed samples positive for CD34 and vimentin.

CONCLUSION

The common imaging findings of dermatofibrosarcoma protuberans include a solitary, superficial, subcutaneous solid mass, various homogenous or heterogeneous enhancements due to degenerative areas. Computed tomographic scan is helpful to detect the size, location, depth and range of this tumor.

A case of myxoid dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is a slowly growing dermal spindle cell tumor and its myxoid variant, a rare type of DFSP, is characterized by extensive myxoid degeneration. We present the case of a 69-year-old woman with a multinodular reddish plaque on her trunk. Histopathologically, the tumor was located in the dermis and consisted of uniform spindle-shaped cells, showing strongly positive reaction for CD34, and negative for both S-100 and desmin. In addition to the typical storiform pattern, prominent myxoid stromal changes were demonstrated. Herein, we report an interesting case of myxoid DFSP, rarely reported in the dermatology literature.

Immunohistochemical analysis of CXCR4 expression in fibrohistiocytic tumors

Functional chemokine receptors are expressed in many malignant tumors. These receptors promote tumor growth and metastasis in response to endogenous chemokines. We analyzed the expression of CXCR4, CCR6 and CCR7 in fibrohistiocytic tumors, including dermatofibrosarcoma protuberance (DFSP), malignant fibrous histiocytoma (MFH), dermatofibroma (DF) using immunohistochemistry. We also investigated the relationship between CXCR4 and CD34, the latter of which is an immunohistochemical marker for DFSP. We observed a higher expression of CXCR4 in DFSP and MFH as compared with DF. Interestingly, a significantly higher expression of CXCR4 was detected in relapsed DFSP than in non-relapsed DFSP, but no significant differences were detected between non-relapsed DFSP and DFSP with CD34 immunostaining. Moreover, MFH had strong immunoreactivity for CXCR4, CCR6 and CCR7. These findings suggest that the assessment of CXCR4 immunoreactivity in fibrohistiocytic tumors is a useful tool for predicting tumor aggressiveness.

D2-40, a novel immunohistochemical marker in differentiating dermatofibroma from dermatofibrosarcoma protuberans

The distinction between dermatofibroma, particularly cellular variant, and dermatofibrosarcoma protuberans in excisional biopsies is usually straightforward. However, a separation between the two may be sometimes challenging, especially in superficial biopsies. Although factor XIIIa and CD34 immunostains are useful in differentiating dermatofibroma and dermatofibrosarcoma protuberans in most instances, focal CD34 positivity may be seen in cellular fibrous histiocytoma. Some cases reveal overlapping immunostain results. D2-40 identifies a 40-kDa O-linked sialoglycoprotein present on a variety of tissues including testicular germ cell tumors as well as lymphatic endothelium. In this study, we investigated the utility of D2-40 in separating dermatofibroma from dermatofibrosarcoma protuberans and compared the results with other commonly used immunostains. Fifty-six cases of dermatofibroma (including six cellular variant) and 29 cases of dermatofibrosarcoma protuberans were retrieved from the archives of Department of Anatomic Pathology at Sunnybrook Health Sciences Center in University of Toronto. We applied factor XIIIa, CD34, and monoclonal mouse anti-D2-40 immunostains to formalin-fixed, paraffin-embedded tissue sections. All 56 (100%) cases of dermatofibroma demonstrated strong and diffuse immunoreactivity to D2-40 in the spindle cells and stroma. Similarly, factor XIIIa showed strong and diffuse positivity in the spindle cells. Nearly all dermatofibromas were negative for CD34 except one case revealing focal positivity. None of dermatofibrosarcoma protuberans cases were labeled by D2-40, although four cases showed weak and patchy background staining in contrary to diffuse, strong, and crisp staining seen in dermatofibromas. Our results indicate that D2-40 seems to be a sensitive immunohistochemical marker for dermatofibromas, including cellular variant. Focal and faint D2-40 staining may be seen in the stroma of dermatofibrosarcoma protuberans. Our findings suggest that D2-40 can be used as a complementary immunostain to factor XIIIa and CD34 in problematic and challenging cases on superficial biopsies.

CD34(+) fibrocytes in melanocytic nevi and malignant melanomas of the skin

CD34(+) fibrocytes are constitutive elements of the human connective tissue. The stroma associated with invasive carcinomas is characterized by a stereotypic loss of CD34(+) fibrocytes and a phenotype change towards CD34(-) alpha-Smooth muscle actin (SMA)(+) myofibroblasts. Secreted protein acidic and rich in cysteine (SPARC) is an important mediator of tumor-associated stromal remodeling. Melanocytic lesions of the skin have not been investigated as to this aspect up to now. Thus, we investigated a total of 20 malignant melanomas and 29 melanocytic nevi. The normal dermis and benign melanocytic nevi showed numerous CD34(+) fibrocytes, whereas malignant melanomas were devoid of this cell type. alpha-SMA-positive myofibroblasts were absent from the normal dermis, melanocytic nevi, and malignant melanomas. SPARC was positive in malignant melanoma cells and negative in their associated stroma, while all melanocytic nevi were completely negative. The stromal phenotype of malignant melanomas (CD34(-) alpha-SMA(-)) differs from that of invasive carcinomas (CD34(-) alpha-SMA(+)) suggesting different pathogenic mechanisms involved in tumor-associated stromal remodeling. SPARC expression appears to be closely related to malignancy in melanocytic lesions.

Congenital atrophic dermatofibrosarcoma protuberans in a 7-month-old boy treated with Mohs micrographic surgery

Dermatofibrosarcoma protuberans is a rare, malignant, slow-growing, locally invasive tumor of the skin. Although most cases are acquired and diagnosed in adulthood, there have been an increasing number of congenital dermatofibrosarcoma protuberans mimicking benign birthmarks described in the literature. The clinical presentation of this tumor is often one of an indurated exophytic plaque or nodule; however, a rare variant can present as atrophic or sclerotic in nature. We report a case of congenital atrophic dermatofibrosarcoma protuberans of the groin in a 7-month-old boy, successfully treated with Mohs micrographic surgery.

Apolipoprotein D in CD34-positive and CD34-negative cutaneous neoplasms: a useful marker in differentiating superficial acral fibromyxoma from dermatofibrosarcoma protuberans

More recent techniques to characterize the genetic profile of soft-tissue tumors include the use of gene arrays. Using this technique, Apolipoprotein D (Apo D), a 33-kDa glycoprotein component of high-density lipoprotein, has been found to be highly expressed in dermatofibrosarcoma protuberans. To corroborate these results, we sought to ascertain the utility of Apo D by investigating its sensitivity and specificity in a variety of CD34-positive and CD34-negative cutaneous neoplasms including superficial acral fibromyxoma, sclerotic fibromas, and cellular dermatofibromas. Of interest, we found absence of Apo D expression in all four cases of superficial acral fibromyxoma. Of the remaining CD34-positive lesions, Apo D expression was noted in 35/36 (97%) cases of dermatofibrosarcoma protuberans, 3/5 (60%) giant-cell fibroblastomas, 4/4 (100%) sclerotic fibromas, 8/8 (100%) neurofibromas, and 1/1 (100%) solitary fibrous tumor. Of the CD34-negative lesions, Apo D expression was noted in 2/22 (9%) regular dermatofibroma, 23/45 (51%) cellular dermatofibroma, 10/10 (100%) malignant fibrous histiocytoma, 9/10 (90%) atypical fibroxanthoma, 7/8 (86%) cellular neurothekeoma, 9/9 (100%) malignant melanoma, 8/8 (100%) melanocytic nevi (100%), 0/2 superficial angiomyxoma, 0/15 fibromatosis, 0/1 nodular fasciitis, and 1/2 (50%) desmoplastic fibroblastomas. In summary, our findings indicate that Apo D expression is not specific to dermatofibrosarcoma protuberans. Its principal use as an immunohistochemical adjunct lies in its utility in differentiating superficial acral fibromyxoma from dermatofibrosarcoma protuberans. Although strong positive staining of Apo D in a markedly atypical fibrohistiocytic lesion is suggestive of atypical fibroxanthoma and/or malignant fibrous histiocytoma, further studies with the inclusion of other atypical spindled cell neoplasms are required to conclusively prove the same.

Fibrous histiocytoma of the eyelid obliterating the punctum and the canaliculus

A 17-year-old boy with a growth in the medial right lower eyelid obliterating the lower punctum and canaliculus underwent incisional biopsy, which revealed fibrous histiocytoma. The remaining tumor was excised and the eyelid was reconstructed. No recurrence was noted after 1 year of follow-up.

Myxoid Dermatofibrosarcoma Protuberans: A Rare Variant Analyzed in a Series of 23 Cases

The myxoid variant of dermatofibrosarcoma protuberans (DFSPs) is uncommon. It often presents a diagnostic challenge and is important to recognize to prevent both undertreatment and overtreatment. To better characterize this unusual variant of DFSP, 23 myxoid DFSPs (DFSP with greater than 50% myxoid stroma) were retrieved from the authors' consult files. 13 patients were male and 10 were female (median age 40 years; range 9 months to 72 years of age). Tumor size ranged from 1.5 to 11 cm (median 2.8 cm). The most frequent sites were the extremities (9) and head and neck (7), followed by the trunk (4) and anogenital region (3). Grossly, the tumors were white/tan/gray to yellow, firm to gelatinous soft tissue masses. Histologically, tumor stroma ranged from 50 to 100% myxoid (median 80%). The majority of cases displayed an infiltrative sheet-like proliferation of bland spindle cells with palely eosinophilic cytoplasm and stellate nuclei without pleomorphism. The stroma was myxoid with prominent thin-walled vessels. All cases displayed honeycomb infiltration of fat and 16 cases showed cellular areas of more typical DFSP. Four tumors contained pigmented dendritic cells (Bednar variant), 1 showed areas of giant cell fibroblastoma and 1 showed progression to fibrosarcomatous DFSP. Mitoses ranged from 0 to 5 per 10 high power fields. 95% of cases (21 out of 22) were positive for CD34 and all cases were negative for S100 and muscle markers. Clinical follow-up in 8 cases, ranging from 3-21 years, (median follow-up 6 years), revealed local recurrence in 2 cases and no evidence of metastasis. All patients were free of disease following wide excision or excision followed by radiotherapy. In summary, these low-grade lesions are clinically similar to typical DFSP, but their unusual morphology is easily confused with a variety of other tumor types.

Dermatofibrosarcoma protuberans: a surgical disease with a molecular savior

PURPOSE OF REVIEW

Dermatofibrosarcoma protuberans is a low-grade malignancy of the skin and subcutaneous tissues with low potential for the development of distant metastases. This tumor is characterized by infiltrative growth, and a chromosomal translocation involving the COL1A1 gene on chromosome 17 and the gene platelet-derived growth factor B gene on chromosome 22. This review will examine recent data confirming the central role of surgery in managing this disease and new findings for the application of molecularly targeted therapy in patients with unresectable disease.

RECENT FINDINGS

The largest published series of dermatofibrosarcoma protuberans cases has reported that surgery can lead to excellent local control in dermatofibrosarcoma protuberans in over 95% of cases. In patients with metastatic disease, or with locally advanced disease not suitable for surgical excision, inhibition of platelet-derived growth factor receptors with imatinib (Gleevec) can lead to striking clinical results, including complete responses in some patients.

SUMMARY

The identification of platelet-derived growth factor B as a near universal translocation partner in chromosomal rearrangements in dermatofibrosarcoma protuberans has led to the successful application of therapy targeted at platelet-derived growth factor receptors. Although wide surgical excision remains the standard of care, patients with locally advanced disease not suitable for wide surgical excision or with metastatic disease can be managed with the platelet-derived growth factor receptors inhibitor imatinib with high probability of response.

Cutaneous Lesions: Benign and Malignant

This article reviews the clinical characteristics, histology, biologic behavior, and recommended treatment for several benign and malignant lesions that may arise on the head and neck. Nevus sebaceus and congenital melanocytic nevus are two benign lesions that can present at a size of several centimeters. Surgical excision may be considered for cosmetic purposes and to reduce the small risk for the development of malignancy within each lesion. Basal and squamous cell carcinoma, lentigo maligna and lentigo maligna melanoma, dermatofibrosarcoma protuberans, and Merkel cell carcinoma are malignant lesions for which surgical excision is the recommended treatment. Local flap reconstruction may be used to address the surgical defects resulting from excision of these benign and malignant conditions.

Neurofibromatous changes in dermatofibrosarcoma protuberans: a potential pitfall in the diagnosis of a serious cutaneous soft tissue neoplasm

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a low-grade malignant neoplasm that has the potential for aggressive local growth and destruction if not treated appropriately. Although the storiform arrangement of spindle cells in DFSP is relatively characteristic, histologic patterns simulating other benign as well as malignant neoplasms such as dermatofibroma, neurofibroma, malignant fibrous histiocytoma, and atypical fibroxanthoma have been described.

METHODS

We collected and analyzed six cases of probable DFSP in which a specific diagnosis could not be rendered due to the predominant neurofibromatous changes in the histologic sections. In an attempt to reach a definitive diagnosis, the clinical history and physical characteristics of the lesions were taken into account, and all cases were further evaluated using immunostaining for CD34 and S-100 protein.

RESULTS

The average age of the patient was 56 years (range 21-80), and the male to female ratio was 1 : 1. The location of lesions included the scalp, neck, back, and abdomen. All cases displayed two distinct histological patterns: (i) a proliferation of spindle cells with wavy nuclei in a loose mucinous stroma suggesting neural differentiation and (ii) a proliferation of spindle cells which interweaved and filled the reticular dermis extending into the subcutis. The wide variety of clinical impressions and descriptions indicated that the diagnoses were not always straightforward, and clinical information did not always assist in the clinicopathologic correlation. All lesions stained positively for CD34; however, three of six cases also stained positively for S-100. The three cases which were CD34 positive and S-100 negative were likely DFSP, and this was the final diagnosis given. The three cases that were CD34 and S-100 positive did not allow for a straightforward diagnosis.

CONCLUSIONS

DFSP may demonstrate areas with features more characteristic of a benign neural lesion, such as a neurofibroma, which can lead to underdiagnosis and subsequent failure to treat. Clinicians and pathologists should recognize this potential diagnostic pitfall and understand that equivocal clinical information, combined with non-specific immunohistochemical staining patterns, can further complicate the dilemma. In these situations, where DFSP is the likely diagnosis but definitive evidence cannot be obtained, full excision of the lesion should be recommended to avoid mistreatment of a potentially malignant lesion.

Nasolacrimal duct obstruction secondary to dermatofibrosarcoma protuberans

OBJECTIVE

To describe a patient wtih dermatofibrosarcoma protuberans causing a nasolacrimal duct obstruction (NLDO).

DESIGN

Case report.

PARTICIPANT

A 33-year-old female with an NLDO.

RESULTS

We report a patient with NLDO as the presenting sign of a rare tumor of the skin, dermatofibrosarcoma protuberans. The patient presented with epiphora, and after dacryocystorhinostomy was done, histopathology revealed dermatofibrosarcoma protuberans. The clinical course, magnetic resonance imaging, and histopathology are discussed.

CONCLUSION

Obstruction of the lacrimal drainage system can be seen with dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans of the head and neck: treatment with Mohs surgery using inverted horizontal paraffin sections

OBJECTIVE

To describe results of treating dermatofibrosarcoma protuberans of the head and neck with a Mohs surgical technique in which tumor margins were evaluated with inverted horizontal paraffin sections to identify the margin of resection necessary to achieve tumor-free borders.

STUDY DESIGN

Retrospective case study of nine patients.

METHODS

In each case, Mohs surgery using inverted horizontal frozen-section analysis was continued until tumor-free margins were achieved. The tumor-free specimens collected during this procedure were immediately reprocessed by using inverted horizontal paraffin sectioning, and the histological results of the two techniques were compared. To identify the margins of resection needed to achieve tumor-free margins, preoperative lesion size was compared with postoperative defect size.

RESULTS

Paraffin section analysis showed persistent tumor in seven of the nine patients in whom the frozen-section technique was used to clear the tumor. Tumor-free margins were achieved in all patients by using one additional excision. The tumor had spread extensively beyond clinical margins and required a mean minimum margin of 3.7 cm around the gross area of tumor (margin range, 2.5-6.0 cm). Patients treated by this technique showed no local, regional, or distant recurrence at follow-up performed at a mean time of 43 months postoperatively (range, 19-74 mo).

CONCLUSIONS

Dermatofibrosarcoma protuberans of the head and neck is a tumor that shows extensive infiltration beyond gross margins. Wide local excision with 2- to 3-cm margins results in an unacceptably high recurrence rate; larger excisional margins are necessary to remove all disease. Accurate margin identification achieved by using Mohs surgery with rush paraffin section analysis results in complete tumor removal and excellent control rates. This method should be preferred for treatment of dermatofibrosarcoma protuberans of the head and neck.

Dermatofibrosarcoma protuberans, giant cell fibroblastoma, and hybrid lesions in children: clinicopathologic comparative analysis of 28 cases with molecular data--a study from the French Federation of Cancer Centers Sarcoma Group

The clinicopathologic and immunohistochemical features of 28 dermatofibrosarcoma protuberans (DFSP), giant cell fibroblastomas (GCFs), and hybrid lesions occurring in children are presented, including molecular data for seven of them. There were 19 pure adult-type DFSP (9 male and 10 female patients aged between a few days [neonate] and 13 years, median 7 years), 5 pure GCF (all males aged from 2 to 8 years, median 4 years), and 4 hybrid tumors (all males aged from 1 to 4 years, median 2.5 years). Tumor locations in pure adult-type DFSP included the trunk (6) and lower (11) and upper (2) limbs. Pure GCFs were observed on the trunk (4) and knee (1), and hybrid lesions on the trunk (2) and lower (1) and upper (1) extremities. Tumor size (n = 20) ranged from 0.6 to 5 cm (median 2 cm). Histologically, pure DFSP presented as monotonous and infiltrative, low-grade, dermal/hypodermal storiform spindle cell proliferations, sparing adnexal structures. GCF showed a dense fibrous to myxoid matrix containing slender wavy spindle cells and multinucleated giant stromal cells often lining angiectoid spaces. Hybrid lesions showed varying combinations of DFSP and GCF areas. Mitotic activity ranged from 1 to 3 mitoses per 10 high power fields. All tumors were diffusely positive for vimentin and CD34 but negative for smooth muscle actin, desmin, epithelial membrane antigen, and cytokeratins; one pure adult-type DFSP was also S-100 protein positive; <1% of nuclei were Ki67 (Mib-1) positive. One karyotyped adult-type DFSP showed an unbalanced t(17;22) (q22;q13) translocation. Multiplex RT-PCR analysis and sequencing of PCR products in seven cases showed gene fusion transcripts in two pure DFSP, two pure GCFs, and one hybrid lesion. Results were uncertain in one pure GCF; one adult-type DFSP was negative. Treatment procedures were known for 27 patients, consisting of 16 wide excisions and 11 marginal excisions. Follow-up information on 15 widely excised tumors (median 24 months; range 5-144 months) showed no recurrence. Five of six marginally excised lesions with available follow up recurred 2 months to 6 years (median 2 years) after initial surgery; all but one were cured by wide reexcision. None of the tumors metastasized. In conclusion, this study emphasizes 1) the occurrence of adult-type DFSP in children, 2) the close relationship between DFSP and GCF clinically, histologically, and molecularly, 3) the excellent prognostic of these lesions if widely excised, and 4) the diagnostic usefulness of RT-PCR analyses in detecting the gene fusion transcripts resulting from the t(17;22) (q22;q13) in paraffin-embedded tissues.