Fibroxanthoma Research Articles

PRAME Expression Is a Useful Tool in the Diagnosis of Primary and Metastatic Dedifferentiated and Undifferentiated Melanoma.

Although mostly recognized in the metastatic setting dedifferentiated and undifferentiated melanomas are increasingly recognized as cutaneous and, less commonly, mucosal primary tumors. Their diagnosis is challenging and dependent on sampling and recognition of a conventional melanoma precursor and/or detection of a mutation in a conventional melanoma driver gene. PRAME immunohistochemistry has recently become an important ancillary tool in the separation of melanoma from benign nevi, but no comprehensive studies exist regarding its value in the detection of dedifferentiated and undifferentiated melanomas and their separation from atypical fibroxanthoma and pleomorphic dermal sarcoma, the main differential diagnoses on sun-damaged skin. After retrieval from archival files, we performed PRAME immunohistochemistry on 11 primary and 10 metastatic dedifferentiated and undifferentiated melanomas, 11 atypical fibroxanthomas, and 10 pleomorphic dermal sarcomas. Nuclear staining was assigned extent (ranging from 0 to 4 and reflecting the percentage of PRAME-positive tumor nuclei) and intensity scores (graded as absent, weak, moderate, and strong, with assigned scores ranging from 0 to 3) with combined scores ranging from 0 to 7. Both primary and metastatic dedifferentiated and undifferentiated melanomas showed strong and diffuse nuclear PRAME staining with median combined scores of 7. Strong and diffuse staining was also seen in all conventional melanoma precursors except for desmoplastic melanoma. In contrast, PRAME staining in atypical fibroxanthoma and pleomorphic dermal sarcoma was patchy and weak with median combined scores of 2. Our data emphasize the diagnostic utility of PRAME staining as a first screening tool in the detection and workup of dedifferentiated and undifferentiated melanomas, both in the primary and metastatic settings. PRAME immunohistochemistry is particularly helpful as it is also positive in tumors without a recognizable conventional melanoma precursor and in those associated with desmoplastic melanomas, where PRAME is typically found to be negative.

Erosive Pustular Dermatosis of the Scalp Treated with Serial Debridement: Case Report

An 82-year-old man with a past medical history of numerous non-melanoma skin cancers (NMSCs), including unresectable squamous cell carcinoma of the right temple treated with radiation therapy and cemiplimab, presented with worsening erosive pustular dermatosis of the scalp (EPDS). This had initially onset four years prior in the setting of 5-fluorouracil and photodynamic therapy for actinic keratoses. He had failed topical ultra-potent steroids, tacrolimus, and dapsone as well as oral dapsone, doxycycline, and acitretin. The condition’s chronicity and radiation to the area likely exacerbated his EPDS. We pursued serial debridement, followed by clobetasol propionate 0.05% ointment twice daily. The patient reported marked improvement with stable condition between treatments. Upon better control of his EPDS, a suspicious ulcerative lesion under a previously affected area was identified and biopsied, revealing atypical fibroxanthoma. EPDS is an inflammatory dermatosis characterized by pustules, erosions, and crusting, often caused by sun damage, local trauma, and topical medications. First-line treatment is topical corticosteroids. We show that serial debridement is effective for treating recalcitrant EPDS. We emphasize the importance of maintaining adequate control of EPDS to avoid masking suspicious lesions, as the patient demographic affected by EPDS is at high risk for NMSCs.

Atypical fibroxanthoma and pleomorphic dermal sarcoma: Local recurrence and metastasis in a nationwide population-based cohort of 1118 patients

The prognosis of patients with atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS) remains uncertain and no standardized follow-up programs have been established. To recommend a standardized follow-up program of patients with AFX and PDS based on nationwide long-term estimates of local recurrence and metastasis. All patients with AFX and PDS in Denmark between 2002 and 2022 were included. Danish National Registries were used to estimate the risks of local recurrence and metastasis for AFX and PDS. The 5-year risk of local recurrence was 10% for AFX and 17% for PDS. The 5-year risk of metastasis was 0.8% for AFX and 16% for PDS. PDS metastasized within 3years in >90% of the patients with the lungs as the primary metastasis site (50%). Invasion beyond the subcutis, perineural/intravascular infiltration, and increasing age significantly increased the risk of PDS relapse. Risk of misclassification and lack of detailed surgical information. The follow-up of patients with AFX can be limited to clinical visits for 4years. Patients with PDS should be followed with clinical visits and PET/CT twice a year for the first 3years and once a year for a minimum of 1year.

The many faces of Atypical fibroxanthoma.

Atypical fibroxanthoma (AFX) is an uncommon, primary dermal neoplasm of uncertain histogenesis, typically originating in the sun-damage skin of the head and neck of the elderly. Since first description in 1958, ∼3000 cases have been reported in the literature. However, the disease is underreported as the neoplasm is considered a standard diagnosis in the last decades. On the other hand, many earlier reports likely have included non-AFX mimics or aggressive pleomorphic dermal sarcomas. In contrast to its alarming high-grade histology, AFX behaves indolently with rare recurrences/ metastatic rate of <2%. The overall 10- and 20-year disease-specific survival rates are ∼ 100% and 98%, respectively. Histologically, AFX displays undifferentiated pleomorphic spindle cell morphology akin to undifferentiated pleomorphic sarcoma (UPS), a feature that was the basis of the abandoned historical terminology "MFH of skin". However, in contrast to other undifferentiated sarcomatoid neoplasms, AFX is notorious for its highly variable histology with a plethora of patterns, underlining a wide differential diagnosis. Notably, spindle cell, keloid-like, pleomorphic, epithelioid, rhabdoid, clear cell, foamy cell, granular cell, bizarre cell, pseudoangiomatous, inflammatory, osteoclast-rich, and many others have been recognized with varying frequencies. Immunohistochemically, AFX is characterized by nonspecific profile with block-type expression of CD10 and aberrant p53 pattern and lack of pankeratin and other lineage-specific epithelial, mesenchymal, melanocytic and hematolymphoid markers. Sarcomatoid melanoma, spindle cell carcinoma and cutaneous anaplastic large cell lymphoma are major considerations. Distinction of AFX from pleomorphic dermal sarcoma (PDS) is arbitrary and is based on presence of ≥ 1 of four unfavorable histological features: more than minimal subcutaneous involvement, coagulative necrosis, lymphovascular invasion and perineurial invasion.

Mohs micrographic surgery versus wide local excision for the treatment of atypical fibroxanthoma: A retrospective cohort analysis

Mohs micrographic surgery versus wide local excision for the treatment of atypical fibroxanthoma: A retrospective cohort analysis

CLINICOPATHOLOGICAL STUDY OF LIP CANCER - A RETROSPECTIVE ANALYSIS OF 274 CASES

Objective The goal of this study was to describe 274 cases of lip cancer and examine their clinicopathological characteristics. Study Design A retrospective investigation was carried out over a 10-year period at a hospital in southern Brazil. Demographic information, as well as clinical and histological diagnoses of lip cancer, were evaluated. The data were analyzed descriptively. Results A total of the 274 cases were investigated. Of these, male patients (55.8%) in their seventies were more observed. Of the informed data, 86.4% of the individuals had a history of chronic sun exposure. Most lesions were ulcers (83.7%) located in the lower lip (51.7%). The findings corresponded to the surgical excision and revealed that 139 (50.7%) tumors were SCCs and 133 (48.5%) were BCCs. Furthermore, one case (0.4%) of lung metastases and one of atypical fibroxanthoma was diagnosed. In a mean time of 50.3 months, twenty people (7.3%) suffered recurrences. Only 4.2% (6 cases) of the 142 patients with complete follow-up information died. Conclusion Lip cancer is more common in elderly men who engage in outdoor activities. Fortunately, the prognosis and recurrence rate are both positive. The current study provides the scientific community with reliable and epidemiological data on these conditions. The goal of this study was to describe 274 cases of lip cancer and examine their clinicopathological characteristics. A retrospective investigation was carried out over a 10-year period at a hospital in southern Brazil. Demographic information, as well as clinical and histological diagnoses of lip cancer, were evaluated. The data were analyzed descriptively. A total of the 274 cases were investigated. Of these, male patients (55.8%) in their seventies were more observed. Of the informed data, 86.4% of the individuals had a history of chronic sun exposure. Most lesions were ulcers (83.7%) located in the lower lip (51.7%). The findings corresponded to the surgical excision and revealed that 139 (50.7%) tumors were SCCs and 133 (48.5%) were BCCs. Furthermore, one case (0.4%) of lung metastases and one of atypical fibroxanthoma was diagnosed. In a mean time of 50.3 months, twenty people (7.3%) suffered recurrences. Only 4.2% (6 cases) of the 142 patients with complete follow-up information died. Lip cancer is more common in elderly men who engage in outdoor activities. Fortunately, the prognosis and recurrence rate are both positive. The current study provides the scientific community with reliable and epidemiological data on these conditions.

Clinical and Dermoscopic Characteristics of Cutaneous Sarcomas: A Literature Review.

Under the umbrella of cutaneous sarcomas (CS) we include a heterogeneous group of rare, malignant, mesenchymal neoplasia, such as dermatofibrosarcoma protuberans, atypical fibroxanthoma, cutaneous undifferentiated pleomorphic sarcoma, cutaneous angiosarcoma and leiomyosarcoma. Clinical presentation and histopathological examination are the cornerstone of CS diagnosis and classification. There are scarce data in the literature in regards to the clinical and dermatoscopic characteristics of CS and the role of dermatoscopy in their early identification. We performed a literature review, aiming to summarize current data on the clinical and dermatoscopic presentation of the most common types of cutaneous sarcomas that may facilitate early diagnosis and prompt management. Based on the available published data, CS are characterized by mostly unspecific dermatoscopic patterns. Dermatofibrosarcoma protuberans, Kaposi's sarcoma, and in a lesser degree, cutaneous angiosarcoma, may display distinct dermatoscopic features, facilitating their early clinical recognition. In conclusion, dermatoscopy, in conjunction with the overall clinical context, may aid towards suspicion of CS.

Fine needle aspiration cytopathology of pleomorphic dermal sarcoma.

Pleomorphic dermal sarcoma (PDS) is an uncommon cutaneous mesenchymal neoplasm. It is cytomorphologically identical to atypical fibroxanthoma (AFX), but differs due to its invasion beyond the dermis. We undertook an examination of our experience with fine needle aspiration (FNA) biopsy cytology of PDS. Our cytopathology files were searched for examples of PDS with concomitant histopathological verification. FNA biopsy smears and cell collection were performed using standard techniques. Seven cases of PDS were retrieved from four different patients (M:F, 1:1; age range: 63-88 years; mean age = 78 years). All patients (57%) presented with a primary tumour with one having an FNA biopsy of two local recurrences and a single distant metastasis. Five aspirates were from the extremities and two from the head/neck. Tumours ranged from 1.0 to 3.5 cm (mean, 2.2 cm). Specific cytological diagnoses were pleomorphic spindle/epithelioid sarcoma (3 cases), PDS (2), AFX (1), and atypical myofibroblastic lesion, query nodular fasciitis (1). Immunohistochemical (IHC) staining from FNA-generated cell blocks in two cases showed non-specific staining with vimentin in both cases; positive CD10, CD68, and INI-1 staining in one case; and smooth muscle actin expression in the other. Multiple negative stains were performed in both of these cases to exclude malignant melanoma, carcinoma, and specific forms of sarcoma. Cytopathology consisted of a mixture of spindle, epithelioid, and bizarre pleomorphic cells. Coupled with ancillary IHC stains, FNA biopsy can help recognise PDS as a sarcomatous cutaneous neoplasm, but is unable to distinguish PDS from AFX.

In vivo reflectance confocal microscopy findings in a case of atypical fibroxanthoma.

Clinical and dermoscopic features of atypical fibroxanthoma (AFX) are mostly non-diagnostic, so other in vivo diagnostic tools may give additional clues for accurate clinical diagnosis, such as in vivo reflectance confocal microscopy (RCM). However, there has been scarce data on RCM features of AFX in the literature, in only clear cell type. Herein we present a case of epithelioid cell predominant type AFX with RCM findings.

Atypical fibroxanthoma and pleomorphic dermal sarcoma - gene expression analysis compared with undifferentiated cutaneous squamous cell carcinoma.

The histogenetic origin of atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS) has not been definitively elucidated. In addition to a fibroblastic origin, a keratinocytic differentiation is discussed due to strong clinical, histomorphological and molecular genetic similarities with undifferentiated cutaneous squamous cell carcinoma (cSCC). 56 cases (36 AFXs, 8 PDSs, 12 undifferentiated cSCCs) were evaluated for their clinical, histomorphological, and immunohistochemical characteristics. RNA transcriptome analysis was performed on 18 cases (6 AFXs/PDSs, 6 undifferentiated cSCCs, 6 differentiated cSCCs). Clinically, the strong similarities in age, gender and tumor location were confirmed. Without further immunohistochemical staining, histomorphological differentiation between AFX/PDS and undifferentiated cSCC is often impossible. Principal component analysis of the RNA transcriptome analysis showed that AFX/PDS and differentiated cSCC each formed their own cluster, while the undifferentiated cSCCs fall in between these two groups, but without forming a cluster of their own. When examining differentially expressed genes (DEGs), the heat maps showed that there were cases within the undifferentiated cSCC that were more likely to be AFX/PDS than differentiated cSCC based on their expression profile. The results provide evidence of molecular similarities between AFX/PDS and undifferentiated cSCC and suggest a common histogenetic origin.

Atypical fibroxanthoma with osteoclast type giant cells – a case report

Introduction: Atypical fibroxanthoma (AFX) are rare low-grade malignant cutaneous tumours. These tumours are dermally based, circumscribed, tend to be ulcerated, and are typically solitary. AFXs tend to occur in solar damaged skin on elderly individuals. The cytology of these tumours can be alarming, with neoplastic cells showing moderate to severe pleomorphism, epithelioid to spindled forms, and often atypical mitotic figures. A range of histologic variants have been described in the literature, including clear cell, myxoid, pigmented, and plaque like.

15 - A rare cutaneous neoplasm: atypical fibroxanthoma

15 - A rare cutaneous neoplasm: atypical fibroxanthoma

Expression of SATB2 in primary cutaneous sarcomatoid neoplasms: a potential diagnostic pitfall

SATB2 can be used as an immunohistochemical marker for osteoblastic differentiation. The differential diagnosis of a cutaneous sarcomatoid neoplasm sometimes includes osteosarcoma when the tumour concomitantly involves the skin, soft tissue, and bone, or when there is a past medical history of osteosarcoma. As the utility of SATB2 immunohistochemistry in these scenarios was unclear, we aimed to determine the frequency and the pattern of SATB2 expression in a variety of cutaneous sarcomatoid neoplasms. SATB2 expression by immunohistochemistry was evaluated by intensity (0-3) and extent (0-100%) of staining to generate an h-score for each case. Expression levels were classified into high-positive (h-score ≥100), low-positive (20-99), and negative (<20) groups. Positive SATB2 expression was observed in 18/23 (78%) atypical fibroxanthomas (AFX), 10/19 (53%) pleomorphic dermal sarcomas, 9/20 (45%) cutaneous sarcomatoid squamous cell carcinomas, 14/39 (36%) sarcomatoid melanomas, 2/13 (15%) poorly differentiated cutaneous angiosarcomas, 10/17 (59%) high-grade cutaneous leiomyosarcomas, and 7/8 (88%) osteosarcoma controls. With the exception of AFX, all cutaneous neoplasms showed significantly lower average h-scores than osteosarcoma. AFX gave the highest average h-score (71) and percentage of high-positive cases (48%) among all examined cutaneous neoplasms. Only two (1.5%) of all cutaneous cases showed strong intensity of staining. Common SATB2 expression in various cutaneous sarcomatoid neoplasms poses a potential diagnostic pitfall when the differential diagnosis includes osteosarcoma. Requirement of strong staining and a high-positive h-score improves the specificity of SATB2 in differentiating these tumours from osteosarcoma.

Atypical Fibroxanthoma: Outcomes from a Large Single Institution Series.

Atypical fibroxanthomas (AFX) are rare malignant cutaneous neoplasms. Unfortunately, limited clinicopathologic and outcomes data on this cancer exists. We report the clinical, pathologic, and treatment characteristics, as well as oncologic outcomes in this single-institution retrospective analysis. This retrospective cohort study compiled clinical, pathologic, treatment, and outcome data for all patients with AFX on definitive excision diagnosed, evaluated, and treated primarily by surgical resection at a single institution between 2000-2020. Descriptive statistics evaluated clinical and pathologic characteristics. Kaplan-Meier method and Cox proportional-hazards models were used to evaluate overall survival and recurrence-free survival. 78 patients with AFX were identified. The majority were elderly, immunocompetent, Caucasian men. 85% of tumors were located on the head and neck. 63% of patients were correctly diagnosed only after complete resection of the index lesion. The median surgical margin was 1.0cm. Overall, only 1.3% (1/78) of patients developed a local recurrence (RFS). No patients died of disease. This study suggests that resection margins of 1cm achieve excellent local control with close to 99% RFS and 100% disease-specific survival.

Atypical fibroxanthoma

Atypical fibroxanthoma (AFX) is a rare skin tumor characterized by a combination of a «malignant» morphological features and non-aggressive clinical course. Diagnosing AFX is challenging due to histological «diversity» and heterogeneous immunophenotype. The presented review describes the history and evolution of AFX as a nosological form of cancer, its histogenetic origin, pathogenesis and biological potential. The clinical, morphological, immunohistochemical, molecular cytogenetic characteristics and histological subtypes of the tumor as well as differential diagnosis have been presented in detail.

Spindle Cell Carcinoma Arising in Xeroderma Pigmentosum-A Rare Tumour in a Rare Disease.

Dear Editor, Xeroderma pigmentosum (XP) is recognized by cutaneous photosensitivity to ultraviolet radiation leading to pigmentary changes, photophobia, and tendency to develop malignancies such as squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and melanoma.[12] Spindle Cell Carcinoma (SpCC) is an extremely rare variant of SCC. A case of extremely rare spindle cell squamous cell carcinoma (SpSCC) developing in the setting of XP on the cheek of a 9-year-old boy is presented here. A 9-year-old boy, known case of XP, presented to the hospital with an erythematous nodule on the cheek [Figure 1] of size 3 × 3 cm. The patient also had multiple brown to black lentigines of size 0.1 × 0.1 cm intermixed with hypopigmented macules of size 0.1 × 0.1 cm to 0.4 × 0.4 cm over photo exposed areas of the face, neck, chest, upper back, bilateral upper and lower limbs, palms, and soles. A provisional diagnosis of BCC was rendered, nodule excised, and sent for histopathological examination. Microscopic sections revealed a biphasic tumor composed of atypical squamous cells with the presence of squamous pearls in the superficial part of the biopsy [Figure 2]. The deeper part of the lesion exhibited spindle cells in fascicles with greater atypia and the presence of atypical mitosis (2–3/10 high power fields) [Figure 3]. The transition from the squamous cell to spindled cell was quite prominent [Figure 4]. No necrosis was noted. On immunohistochemistry (IHC), there was co-expression of cytokeratin (CK) [Figure 5a] and vimentin [Figure 5b]. The tumor cells were negative for S100 and HMB45. A histopathological diagnosis of SpCC was rendered.Figure 1: Erythematous nodule over the right cheek near-eye with central black crustingFigure 2: Atypical squamous cells with the presence of squamous pearls. (H and E, ×400)Figure 3: Spindled areas with greater atypia. (H and E, ×400)Figure 4: Transition of atypical squamous cells into spindle cells (H and E, ×40)Figure 5: (a) Cytokeratin expression in squamoid areas (IHC, ×400). (b) Vimentin expression in spindled areas (IHC, ×400)The basic defect in XP is the deficient repair of DNA damaged by UV radiation making XP a model disease for sun-induced carcinogenesis. Damaged DNA is removed with the help of NER replaced by new DNA.[3-5] SpCC is a rare poorly differentiated variant of SCC, which portends a worse prognosis compared to the usual SCC. Seen mostly in men in the sixth and seventh decades, it accounts for 1% of all SCCs and mostly is found in the oral cavity, larynx, pharynx. and sinonasal locations. Primary SpSCC of the skin is extremely rare.[5] Exposure to ultraviolet radiation is one of the most important etiological factors in the development of SpSCC. It usually occurs in the backdrop of solar elastosis and lacks keratinization. Exposure to ultraviolet radiation coupled with DNA repair defects possibly made this patient extremely vulnerable to this aggressive neoplasm.[25] The histological diagnosis is quite challenging. The absence of basaloid cells, peripheral palisading, and retraction clefts excluded BCC. Keratoacanthoma was excluded as there was the absence of a keratin-filled central crater surrounded by the epidermal lip. The presence of invasion into the subcutis, absence of actinic changes, and presence of a connection to the overlying epidermis and positivity for CK ruled out atypical fibroxanthoma. Different theories have been proposed to explain the origin of SpCC. It could possibly arise as a result of dedifferentiation of the spindle cells to the epithelial component. The second theory supports the theory of collision tumors and lastly, some studies report that the spindle component may be a reactive proliferation of the stroma.[15] Thus, XP is a rare disease and SpSCC developing in its backdrop further makes it challenging to timely diagnose and manage the condition. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Multiplidisciplinary Actions in the Treatiment of Atypical Fibroxatoma a rare but severe neoplasm: a real-life case report

SUMMARY Atypical Fibroxanthoma (AFX) is a rare tumor of spindle cells, described by Helwig (1963). This is related to sun exposure in whites, elderly men (mean age 60 years). AFX is a variant of malignant fibrous histiocytoma (MFH) and presents as an erythematous, papule and ulcered lesion. The size varies from 2 to 20 cm, and difficult to differentiate from epidermoid carcinoma (SCC). We report the case of patient with lower lip AFX reinforcing adjuvant surgery and radiotherapy (RT). A 60-year-old patient, male, mason, white, from São Paulo. It refers to wound lip for 12 months, with no improvement to treatments. To clinical examination: Ulcer and vegetation lesion of the lower lip compromising the right labial commissure and distant 1.5 cm from the left commissure and infiltrating 0.5 cm to the skin. Lymph node level IB right measuring 1.5 X 1.5 cm hardened, mobile, smooth, without contiguity with the submandibular gland. We performed resection and reconstruction with emptying of levels IA and IB. It evolved with local infections and dehiscence due to lack of local care. The anatomopathological showed low differentiated and ulcerated AFX measuring 6.2 x 3.5 cm with high mitotic index and lymph node level IB right with metastasis, confirmed by immunohistochemical examination. We indicated radiotherapy (RT) in the in the total dose of 60 Gy and was asymptomatic for 24 months. The diagnosis is based on clinical, histopathological and IHQ, and extensive excision with free margins, cervical emptying for suspected LN and associated reconstruction. Radiotherapy has been indicated in this case by prognostics factors. Keywords: Atypical fibroxanthoma; Neoplasm of the lower lip; Diagnosis; Treatment.

Immunohistochemical Characteristics of Atypical Fibroxanthoma and Pleomorphic Dermal Sarcoma: A Systematic Review and Meta-Analysis.

Differentiating atypical fibroxanthoma (AFX) from pleomorphic dermal sarcoma (PDS) remains a challenge. Increasing the use of immunohistochemistry has led to the proposal of many immunomarkers that may aid in the diagnosis of AFX and PDS. In this meta-analysis, we investigate the immunohistochemical characteristics of AFX and PDS based on suggested immunomarkers in the literature. Second, we identify potential distinctive markers found in the tumors' respective immunohistochemical profiles. We included studies using immunomarkers on at least 10 consecutive patients with clinically and histopathologically verified AFX or PDS. The positive rates of the immunomarkers were pooled across the included studies with random-effects models. The immunomarkers were further categorized by a priori-chosen cutoffs in positive rates as positive markers (>90%) or negative markers (<10%). Differences between AFX and PDS were compared with Wald tests. We included 45 studies (1516 tumors) reporting on 35 immunomarkers. CD10 was positive in 94% (95% confidence interval, 87-99) of AFX cases and 100% (95% confidence interval, 99-100) of PDS cases. In accordance with the literature, both AFX and PDS were mainly negative for epithelial markers, melanocytic markers, markers of smooth muscle differentiation, and endothelial markers. None of the examined immunomarkers could distinguish AFX from PDS. Our results suggest that CD10 is a useful positive immunomarker for both AFX and PDS. We found no difference in immunohistochemical profile when comparing AFX with PDS. Our analysis suggests that CD10, AE1/AE3, CK5/CK6, p63, S100, SOX10, desmin, SMA, CD31, and ERG could be used to differentiate AFX and PDS from other spindle cell neoplasms.

Increase of atypical fibroxanthoma and pleomorphic dermal sarcoma: a retrospective analysis of four German skin cancer centers.

In recent years, considerable insight has been gained into the pathogenesis, diagnosis and treatment of cutaneous sarcomas, including atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). Both entities have shown increasing incidence rates in the last decade. This study was initiated to evaluate how these new insights impact the number of diagnoses of AFX/PDS compared to other cutaneous sarcoma entities. In a retrospective study of four German skin cancer centers, all histopathological reports of cutaneous sarcomas (AFX, PDS, dermatofibrosarcoma protuberans, cutaneous leiomyosarcoma, angiosarcoma, and Kaposi sarcoma) confirmed by board-certified dermatopathologists were analyzed during a time-period of seven years (2013-2019). Additionally, utilization of immunohistochemical markers (including pan-cytokeratin, S100, desmin, CD34, CD10, procollagen-1, CD99, CD14, and CD68) as an adjunct to diagnose AFX/PDS was recorded. Overall, 255 cutaneous sarcomas were included in the present study. The diagnosis of a cutaneous sarcoma has consequently risen from 2013 to 2019 (from 16 to 52 annual cases). The results of AFX/PDS revealed 4.6 times more diagnoses in 2019 than in 2013. Atypical fibroxanthoma represented the most common subtype, displaying 49.3% of all diagnosed cutaneous sarcomas. Additionally, the increase of AFX/PDS was linked to the use of immunohistochemistry, with specific immunohistochemical markers used in 57.1% of cases in 2013 compared to 100% in 2019. This retrospective study of four German skin cancer centers demonstrates a substantial rise of AFX/PDS, possibly due to recently established diagnostic and terminology standards. This rise is probably linked to increased utilization of specific immunohistochemical markers. Atypical fibroxanthoma/PDS may be more common than previously thought and seems to represent the most frequent cutaneous sarcoma subtype.

Mohs micrographic surgery in rare cutaneous tumors: a retrospective study at a Brazilian tertiary university hospital

BackgroundMohs micrographic surgery is an established technique in the treatment of cutaneous neoplasms. It offers higher cure rates and the main indications are non-melanoma malignant skin tumors. Few studies have been performed on the treatment of rare tumors through this technique. ObjectiveTo study rare skin tumors and rare variants of basal cell carcinoma and squamous cell carcinoma submitted to Mohs micrographic surgery in a tertiary service in relation to frequency, disease-free evolution, and applicability of this surgical procedure for this group of tumors. MethodsThis was a retrospective observational study including rare skin tumors and less common variants of basal cell carcinoma and squamous cell carcinoma treated using Mohs micrographic surgery, between October 2008 and April 2021. ResultsDuring the study period, 437 tumors were treated using Mohs micrographic surgery, and 22 (5%) rare skin tumors were selected. The tumors comprised three dermatofibrosarcomas protuberans, two atypical fibroxanthomas, two spiradenomas, two hypercellular fibrohistiocytomas, one primary cutaneous adenocarcinoma, one trichoblastoma, one porocarcinoma, one chondroid syringoma, one cutaneous angiosarcoma, one Merkel cell carcinoma, and one sebaceous carcinoma. Six other cases of rare basal cell carcinoma variants with trichoepitheliomatous differentiation, metatypical basal cell carcinoma, and clear cell squamous cell carcinoma were included. There were no cases of recurrence after an average of six years of follow-up. Study limitationsThis is a retrospective study on rare neoplasms carried out in a single referral center, and this surgical technique isn’t widely available in the public service. ConclusionThis retrospective case series showed that Mohs micrographic surgery is an appropriate treatment for rare skin tumors. They corresponded to 5% of the tumors treated by the technique during a 12-year-period, with no recurrences identified.