Atrophic Dermatofibrosarcoma Protuberans: A Case Report and Reappraisal of the Literature

Dermatofibrosarcoma protuberans (DFSP) is an uncommon cutaneous tumor of intermediate malignancy that is known to be locally aggressive.1 It is thought to be of fibrohistiocytic origin and accounts for 1% of all soft tissue malignancies.2 DFSP occurs in men and women with equal incidence, mostly on the trunk and less commonly on the proximal extremities, with a higher incidence in Caucasians. Most patients present between the second and fifth decades, though the disease can be noted in any age group and any anatomic location.3

Four clinical variants of early DFSP are thought to exist: confluent nodular lesions forming a sclerotic plaque, keloidlike sclerotic plaque, tumor, and atrophic plaque.4,5 The usual clinical appearance of DFSP at an early stage is as a slow-growing, asymptomatic plaque or nodule. The tumor's gross pathology is of a gray-white mass involving the dermis and subcutis; histologically, it is a poorly circumscribed infiltrative spindle cell tumor. The spindle cells, which are CD34+, are arranged in a storiform pattern described as a dense, poorly circumscribed, monomorphic cell proliferation arranged in fascicles that often reach and infiltrate the hypodermis.6,7 The 3 recognized histologic variants of DFSP are fibrosarcomatous, plaquelike, and myxoid forms.8 The infiltrating pattern accounts for the tumor's common recurrence after excision and the need for wide excision or Mohs micrographic surgery for curative removal.2,3,9-11 One recent review of atrophic DFSP implicated chromosomal translocations or the formation of supernumerary ring chromosomes in the pathogenesis of DFSP.12 These chromosomal events result in the fusion of the collagen type 1α1 gene with the platelet-derived growth factor-β chain gene. How this mutation could contribute to the atrophic phenotype is unknown.12 This review documents only 25 cases of atrophic DFSP in the literature. We present a case involving a woman who had an atrophic DFSP treated successfully with Mohs micrographic surgery and review 35 cases in the literature regarding this rare presentation of DFSP. 

Case Report

A 41-year-old white woman presented with a 12-year history of a well-demarcated, scalloped, markedly depressed, reddish brown, slightly firm, 4x5-cm plaque on the right chest (Figure 1). On initial evaluation, the patient denied prior trauma to the area or any past manipulation of the lesion. The patient's preoperative clinical differential diagnosis included atrophoderma of Pasini and Pierini, anetoderma, morphea, and lipoatrophy.

A punch biopsy of the lesion was performed. Results revealed a spindle cell neoplasm that was thought to be a dermatofibroma. The entire lesion was subsequently excised. Histopathology results of the excision specimen demonstrated atrophy of the dermis and a permeative spindle cell neoplasm with scattered multinucleated giant cells involving the dermis and underlying soft tissue with a few areas of a storiform growth pattern (Figure 2). The lesion also was diffusely immunoreactive for CD34 and extended to the margins of the specimen. A diagnosis of DFSP was made, and the patient was treated with Mohs micrographic surgery. Three stages of surgery were performed, and the final defect was 7.0x8.5 cm. The patient elected to allow the wound to heal by secondary intention. There was no evidence of recurrence 12 months after the procedure.

Comment

The atrophic presentation of DFSP is the rarest variant of this infrequent neoplasm. Although this subject was recently reviewed, there are several other important issues in the literature that need to be clarified regarding this unusual phenotype.12 For a lesion to be classified as atrophic, there should be both clinical and histologic evidence of atrophy. When the epidermis is atrophic, the result is shiny smooth skin clinically and flattening of the rete ridges histopathologically. Conversely, when the dermis or subcutaneous tissue is atrophic, the result is a loss in skin thickness and a corresponding loss of collagen bundles or subcutaneous fat histopathologically.13

Epidermal atrophy is commonly noted histologically in DFSP cases that present in the usual fashion.14,15 Only rarely has DFSP presented as a clinically depressed lesion.16-20 Even more rare is a documentation of dermal atrophy.12,21 We report a case of DFSP in which the initial lesion was an atrophic depression of the skin lacking nodularity and histologically demonstrating significant dermal atrophy.

A number of cases have been reported describing atrophic presentations of DFSP (Table 1).4,5,8,12,16-26 However, as Davis and Sanchez8 noted, rarely does a so-called atrophic DFSP present as a visible depression in the skin.16-21 Clearly, there is some discrepancy in the literature as to the nature of atrophy in relation to the clinical presentation of DFSP. Some authors have even speculated that the atrophic variant of DFSP is nothing more than an early presentation of the more usual DFSP prior to the formation of nodules.4 However, the fact that our patient had her lesion for 12 years prior to treatment without the formation of a nodular component indicates that the atrophic variant of DFSP is a real entity.

Table 2 demonstrates the sex and anatomic location of the patients in the 35 reported cases of DFSP described as atrophic or morpheaform, including the present case. The majority (20/35) of cases have been in female patients, and the most common location in both sexes has been the trunk (24/35). The next most common location was the lower extremity (7/35).

Table 3 documents the age and anatomic location of the 9 cases clinically described as resembling lipoatrophy, atrophoderma or anetoderma, or that were significantly clinically depressed based on clinical photographs, ie, the cases most similar to the one we now present.4,16,19-21,25 Three of the 9 cases were on the trunks of females aged 16 to 41 years. Interestingly, 4 of the remaining 6 cases were on the lower extremities of children aged 18 months to 16 years.

A number of conclusions can be drawn from this data. First, atrophic variants of DFSP tend to occur most often on the trunk, as do the usual variants of DFSP. However, the atrophic variants tend to occur more often in females as opposed to the standard presentation of DFSP, which occurs with equal frequency in males and females. In addition, a distinction exists in the presentation of atrophic lesions, which can have either a morpheaform or a more clinically depressed appearance, mimicking such disorders as anetoderma, atrophoderma, or lipoatrophy. We report such a case mimicking atrophoderma, and we contend that this is the rarest presentation of atrophic DFSP.

One final entity in the differential diagnosis of a depressed plaque on the trunk would be an atrophic dermatofibroma. The dermatofibroma, a well-known and benign cousin of DFSP, is often noted to have some dermal atrophy grossly with lateral pressure, described as a dimple sign.27 As Requena and Reichel28 pointed out, even when there is a central depression over a dermatofibroma without lateral pressure, no true loss of the dermis is seen histopathologically. As such, this central depression doesn't represent true dermal atrophy.28 However, the dermatofibroma also can present as a depressed lesion demonstrating thinning of the dermis histologically, and this variety of dermatofibroma has been described as atrophic.28-31 Although a recently published article recommended considering a diagnosis of atrophic dermatofibroma in the case of "atrophic, depressed lesions on the upper body of middle-aged women,"31 we would maintain that atrophic DFSP also should be considered in the differential diagnosis.

One possibility to clarify the imprecision in the literature in relation to the clinical presentation of DFSP would be to eliminate protuberans from the name, thereby recognizing that some lesions that are histologically proven to be DFSP can present without nodularity and with epidermal or dermal atrophy. This change in the nomenclature was first proposed by Lambert et al23 and was reiterated by Page and Assaad.16 Perhaps a greater awareness that DFSP can present as atrophic lesions without nodules could lead to earlier diagnosis and decreased morbidity with smaller curative surgeries when the lesions are recognized at an earlier stage. The atrophic variant of DFSP does not carry a different prognosis compared with the traditional variant; Mohs micrographic surgery is still the treatment of choice, providing a low rate of recurrence. Atrophic DFSP should be kept in the differential diagnosis for atrophic, depressed lesions, particularly those seen on the trunks of women or on the lower extremities of children. 

Dermatofibrosarcoma protuberans (DFSP) is an uncommon cutaneous tumor of intermediate malignancy that is known to be locally aggressive.1 It is thought to be of fibrohistiocytic origin and accounts for 1% of all soft tissue malignancies.2 DFSP occurs in men and women with equal incidence, mostly on the trunk and less commonly on the proximal extremities, with a higher incidence in Caucasians. Most patients present between the second and fifth decades, though the disease can be noted in any age group and any anatomic location.3

Four clinical variants of early DFSP are thought to exist: confluent nodular lesions forming a sclerotic plaque, keloidlike sclerotic plaque, tumor, and atrophic plaque.4,5 The usual clinical appearance of DFSP at an early stage is as a slow-growing, asymptomatic plaque or nodule. The tumor's gross pathology is of a gray-white mass involving the dermis and subcutis; histologically, it is a poorly circumscribed infiltrative spindle cell tumor. The spindle cells, which are CD34+, are arranged in a storiform pattern described as a dense, poorly circumscribed, monomorphic cell proliferation arranged in fascicles that often reach and infiltrate the hypodermis.6,7 The 3 recognized histologic variants of DFSP are fibrosarcomatous, plaquelike, and myxoid forms.8 The infiltrating pattern accounts for the tumor's common recurrence after excision and the need for wide excision or Mohs micrographic surgery for curative removal.2,3,9-11 One recent review of atrophic DFSP implicated chromosomal translocations or the formation of supernumerary ring chromosomes in the pathogenesis of DFSP.12 These chromosomal events result in the fusion of the collagen type 1α1 gene with the platelet-derived growth factor-β chain gene. How this mutation could contribute to the atrophic phenotype is unknown.12 This review documents only 25 cases of atrophic DFSP in the literature. We present a case involving a woman who had an atrophic DFSP treated successfully with Mohs micrographic surgery and review 35 cases in the literature regarding this rare presentation of DFSP. 

Case Report

A 41-year-old white woman presented with a 12-year history of a well-demarcated, scalloped, markedly depressed, reddish brown, slightly firm, 4x5-cm plaque on the right chest (Figure 1). On initial evaluation, the patient denied prior trauma to the area or any past manipulation of the lesion. The patient's preoperative clinical differential diagnosis included atrophoderma of Pasini and Pierini, anetoderma, morphea, and lipoatrophy.

A punch biopsy of the lesion was performed. Results revealed a spindle cell neoplasm that was thought to be a dermatofibroma. The entire lesion was subsequently excised. Histopathology results of the excision specimen demonstrated atrophy of the dermis and a permeative spindle cell neoplasm with scattered multinucleated giant cells involving the dermis and underlying soft tissue with a few areas of a storiform growth pattern (Figure 2). The lesion also was diffusely immunoreactive for CD34 and extended to the margins of the specimen. A diagnosis of DFSP was made, and the patient was treated with Mohs micrographic surgery. Three stages of surgery were performed, and the final defect was 7.0x8.5 cm. The patient elected to allow the wound to heal by secondary intention. There was no evidence of recurrence 12 months after the procedure.

Comment

The atrophic presentation of DFSP is the rarest variant of this infrequent neoplasm. Although this subject was recently reviewed, there are several other important issues in the literature that need to be clarified regarding this unusual phenotype.12 For a lesion to be classified as atrophic, there should be both clinical and histologic evidence of atrophy. When the epidermis is atrophic, the result is shiny smooth skin clinically and flattening of the rete ridges histopathologically. Conversely, when the dermis or subcutaneous tissue is atrophic, the result is a loss in skin thickness and a corresponding loss of collagen bundles or subcutaneous fat histopathologically.13

Epidermal atrophy is commonly noted histologically in DFSP cases that present in the usual fashion.14,15 Only rarely has DFSP presented as a clinically depressed lesion.16-20 Even more rare is a documentation of dermal atrophy.12,21 We report a case of DFSP in which the initial lesion was an atrophic depression of the skin lacking nodularity and histologically demonstrating significant dermal atrophy.

A number of cases have been reported describing atrophic presentations of DFSP (Table 1).4,5,8,12,16-26 However, as Davis and Sanchez8 noted, rarely does a so-called atrophic DFSP present as a visible depression in the skin.16-21 Clearly, there is some discrepancy in the literature as to the nature of atrophy in relation to the clinical presentation of DFSP. Some authors have even speculated that the atrophic variant of DFSP is nothing more than an early presentation of the more usual DFSP prior to the formation of nodules.4 However, the fact that our patient had her lesion for 12 years prior to treatment without the formation of a nodular component indicates that the atrophic variant of DFSP is a real entity.

Table 2 demonstrates the sex and anatomic location of the patients in the 35 reported cases of DFSP described as atrophic or morpheaform, including the present case. The majority (20/35) of cases have been in female patients, and the most common location in both sexes has been the trunk (24/35). The next most common location was the lower extremity (7/35).

Table 3 documents the age and anatomic location of the 9 cases clinically described as resembling lipoatrophy, atrophoderma or anetoderma, or that were significantly clinically depressed based on clinical photographs, ie, the cases most similar to the one we now present.4,16,19-21,25 Three of the 9 cases were on the trunks of females aged 16 to 41 years. Interestingly, 4 of the remaining 6 cases were on the lower extremities of children aged 18 months to 16 years.

A number of conclusions can be drawn from this data. First, atrophic variants of DFSP tend to occur most often on the trunk, as do the usual variants of DFSP. However, the atrophic variants tend to occur more often in females as opposed to the standard presentation of DFSP, which occurs with equal frequency in males and females. In addition, a distinction exists in the presentation of atrophic lesions, which can have either a morpheaform or a more clinically depressed appearance, mimicking such disorders as anetoderma, atrophoderma, or lipoatrophy. We report such a case mimicking atrophoderma, and we contend that this is the rarest presentation of atrophic DFSP.

One final entity in the differential diagnosis of a depressed plaque on the trunk would be an atrophic dermatofibroma. The dermatofibroma, a well-known and benign cousin of DFSP, is often noted to have some dermal atrophy grossly with lateral pressure, described as a dimple sign.27 As Requena and Reichel28 pointed out, even when there is a central depression over a dermatofibroma without lateral pressure, no true loss of the dermis is seen histopathologically. As such, this central depression doesn't represent true dermal atrophy.28 However, the dermatofibroma also can present as a depressed lesion demonstrating thinning of the dermis histologically, and this variety of dermatofibroma has been described as atrophic.28-31 Although a recently published article recommended considering a diagnosis of atrophic dermatofibroma in the case of "atrophic, depressed lesions on the upper body of middle-aged women,"31 we would maintain that atrophic DFSP also should be considered in the differential diagnosis.

One possibility to clarify the imprecision in the literature in relation to the clinical presentation of DFSP would be to eliminate protuberans from the name, thereby recognizing that some lesions that are histologically proven to be DFSP can present without nodularity and with epidermal or dermal atrophy. This change in the nomenclature was first proposed by Lambert et al23 and was reiterated by Page and Assaad.16 Perhaps a greater awareness that DFSP can present as atrophic lesions without nodules could lead to earlier diagnosis and decreased morbidity with smaller curative surgeries when the lesions are recognized at an earlier stage. The atrophic variant of DFSP does not carry a different prognosis compared with the traditional variant; Mohs micrographic surgery is still the treatment of choice, providing a low rate of recurrence. Atrophic DFSP should be kept in the differential diagnosis for atrophic, depressed lesions, particularly those seen on the trunks of women or on the lower extremities of children. 

Dermatofibrosarcoma protuberans (DFSP) is an uncommon cutaneous tumor of intermediate malignancy that is known to be locally aggressive.1 It is thought to be of fibrohistiocytic origin and accounts for 1% of all soft tissue malignancies.2 DFSP occurs in men and women with equal incidence, mostly on the trunk and less commonly on the proximal extremities, with a higher incidence in Caucasians. Most patients present between the second and fifth decades, though the disease can be noted in any age group and any anatomic location.3

Four clinical variants of early DFSP are thought to exist: confluent nodular lesions forming a sclerotic plaque, keloidlike sclerotic plaque, tumor, and atrophic plaque.4,5 The usual clinical appearance of DFSP at an early stage is as a slow-growing, asymptomatic plaque or nodule. The tumor's gross pathology is of a gray-white mass involving the dermis and subcutis; histologically, it is a poorly circumscribed infiltrative spindle cell tumor. The spindle cells, which are CD34+, are arranged in a storiform pattern described as a dense, poorly circumscribed, monomorphic cell proliferation arranged in fascicles that often reach and infiltrate the hypodermis.6,7 The 3 recognized histologic variants of DFSP are fibrosarcomatous, plaquelike, and myxoid forms.8 The infiltrating pattern accounts for the tumor's common recurrence after excision and the need for wide excision or Mohs micrographic surgery for curative removal.2,3,9-11 One recent review of atrophic DFSP implicated chromosomal translocations or the formation of supernumerary ring chromosomes in the pathogenesis of DFSP.12 These chromosomal events result in the fusion of the collagen type 1α1 gene with the platelet-derived growth factor-β chain gene. How this mutation could contribute to the atrophic phenotype is unknown.12 This review documents only 25 cases of atrophic DFSP in the literature. We present a case involving a woman who had an atrophic DFSP treated successfully with Mohs micrographic surgery and review 35 cases in the literature regarding this rare presentation of DFSP. 

Case Report

A 41-year-old white woman presented with a 12-year history of a well-demarcated, scalloped, markedly depressed, reddish brown, slightly firm, 4x5-cm plaque on the right chest (Figure 1). On initial evaluation, the patient denied prior trauma to the area or any past manipulation of the lesion. The patient's preoperative clinical differential diagnosis included atrophoderma of Pasini and Pierini, anetoderma, morphea, and lipoatrophy.

A punch biopsy of the lesion was performed. Results revealed a spindle cell neoplasm that was thought to be a dermatofibroma. The entire lesion was subsequently excised. Histopathology results of the excision specimen demonstrated atrophy of the dermis and a permeative spindle cell neoplasm with scattered multinucleated giant cells involving the dermis and underlying soft tissue with a few areas of a storiform growth pattern (Figure 2). The lesion also was diffusely immunoreactive for CD34 and extended to the margins of the specimen. A diagnosis of DFSP was made, and the patient was treated with Mohs micrographic surgery. Three stages of surgery were performed, and the final defect was 7.0x8.5 cm. The patient elected to allow the wound to heal by secondary intention. There was no evidence of recurrence 12 months after the procedure.

Comment

The atrophic presentation of DFSP is the rarest variant of this infrequent neoplasm. Although this subject was recently reviewed, there are several other important issues in the literature that need to be clarified regarding this unusual phenotype.12 For a lesion to be classified as atrophic, there should be both clinical and histologic evidence of atrophy. When the epidermis is atrophic, the result is shiny smooth skin clinically and flattening of the rete ridges histopathologically. Conversely, when the dermis or subcutaneous tissue is atrophic, the result is a loss in skin thickness and a corresponding loss of collagen bundles or subcutaneous fat histopathologically.13

Epidermal atrophy is commonly noted histologically in DFSP cases that present in the usual fashion.14,15 Only rarely has DFSP presented as a clinically depressed lesion.16-20 Even more rare is a documentation of dermal atrophy.12,21 We report a case of DFSP in which the initial lesion was an atrophic depression of the skin lacking nodularity and histologically demonstrating significant dermal atrophy.

A number of cases have been reported describing atrophic presentations of DFSP (Table 1).4,5,8,12,16-26 However, as Davis and Sanchez8 noted, rarely does a so-called atrophic DFSP present as a visible depression in the skin.16-21 Clearly, there is some discrepancy in the literature as to the nature of atrophy in relation to the clinical presentation of DFSP. Some authors have even speculated that the atrophic variant of DFSP is nothing more than an early presentation of the more usual DFSP prior to the formation of nodules.4 However, the fact that our patient had her lesion for 12 years prior to treatment without the formation of a nodular component indicates that the atrophic variant of DFSP is a real entity.

Table 2 demonstrates the sex and anatomic location of the patients in the 35 reported cases of DFSP described as atrophic or morpheaform, including the present case. The majority (20/35) of cases have been in female patients, and the most common location in both sexes has been the trunk (24/35). The next most common location was the lower extremity (7/35).

Table 3 documents the age and anatomic location of the 9 cases clinically described as resembling lipoatrophy, atrophoderma or anetoderma, or that were significantly clinically depressed based on clinical photographs, ie, the cases most similar to the one we now present.4,16,19-21,25 Three of the 9 cases were on the trunks of females aged 16 to 41 years. Interestingly, 4 of the remaining 6 cases were on the lower extremities of children aged 18 months to 16 years.

A number of conclusions can be drawn from this data. First, atrophic variants of DFSP tend to occur most often on the trunk, as do the usual variants of DFSP. However, the atrophic variants tend to occur more often in females as opposed to the standard presentation of DFSP, which occurs with equal frequency in males and females. In addition, a distinction exists in the presentation of atrophic lesions, which can have either a morpheaform or a more clinically depressed appearance, mimicking such disorders as anetoderma, atrophoderma, or lipoatrophy. We report such a case mimicking atrophoderma, and we contend that this is the rarest presentation of atrophic DFSP.

One final entity in the differential diagnosis of a depressed plaque on the trunk would be an atrophic dermatofibroma. The dermatofibroma, a well-known and benign cousin of DFSP, is often noted to have some dermal atrophy grossly with lateral pressure, described as a dimple sign.27 As Requena and Reichel28 pointed out, even when there is a central depression over a dermatofibroma without lateral pressure, no true loss of the dermis is seen histopathologically. As such, this central depression doesn't represent true dermal atrophy.28 However, the dermatofibroma also can present as a depressed lesion demonstrating thinning of the dermis histologically, and this variety of dermatofibroma has been described as atrophic.28-31 Although a recently published article recommended considering a diagnosis of atrophic dermatofibroma in the case of "atrophic, depressed lesions on the upper body of middle-aged women,"31 we would maintain that atrophic DFSP also should be considered in the differential diagnosis.

One possibility to clarify the imprecision in the literature in relation to the clinical presentation of DFSP would be to eliminate protuberans from the name, thereby recognizing that some lesions that are histologically proven to be DFSP can present without nodularity and with epidermal or dermal atrophy. This change in the nomenclature was first proposed by Lambert et al23 and was reiterated by Page and Assaad.16 Perhaps a greater awareness that DFSP can present as atrophic lesions without nodules could lead to earlier diagnosis and decreased morbidity with smaller curative surgeries when the lesions are recognized at an earlier stage. The atrophic variant of DFSP does not carry a different prognosis compared with the traditional variant; Mohs micrographic surgery is still the treatment of choice, providing a low rate of recurrence. Atrophic DFSP should be kept in the differential diagnosis for atrophic, depressed lesions, particularly those seen on the trunks of women or on the lower extremities of children.