An unusual presentation of dermatofibrosarcoma protuberans: A case of fibrosarcomatous dermatofibrosarcoma protuberans with pleomorphic angiectatic tumor-like changes.

Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive superficial mesenchymal neoplasm characterized by monomorphic spindle-cell proliferation with a storiform pattern. It can demonstrate pigmentation, myxoid changes, myoid differentiation, plaque-like growth, and fibrosarcomatous features; its varied presentation often complicates diagnosis. We report an extremely rare case of fibrosarcomatous DFSP with features reminiscent of a pleomorphic hyalinizing angiectatic tumor (PHAT) in a 73-year-old male. The diagnosis was confirmed using a reverse transcription polymerase chain reaction. To the best of our knowledge, PHAT-like changes in DFPS have not been described so far. Therefore, this report provides a novel variant of DFSP and expands the differential diagnosis of DFSP and PHAT.

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors. / [Artículo traducido] Revisión del rol de la cirugía micrográfica con cortes en parafina en el tratamiento de tumores cutáneos.

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

In vitro modeling of recurrent Dermatofibrosarcoma Protuberans: Assessment of 5-aminolevulinic acid photodynamic therapy efficacy.

BACKGROUND: Dermatofibrosarcoma Protuberans (DFSP) is a rare, low-grade malignant tumor of the dermis with a high recurrence rate post-surgery. Current treatments, including surgery, radiotherapy, and targeted therapy, have limitations. Photodynamic therapy (PDT) with 5-aminolevulinic acid (5-ALA) is a promising non-invasive approach, but its efficacy in DFSP treatment remains underexplored. METHODS: This study aimed to evaluate the anti-tumor efficacy of 5-ALA PDT using an in vitro model derived from a recurrent DFSP patient. The cells were treated with varying concentrations of 5-ALA and exposed to red light, followed by assessments of cell viability, proliferation, apoptosis, migration, invasion, angiogenesis, and expression of DFSP-related genes and proteins. RESULTS: 5-ALA PDT significantly reduced DFSP cell viability in a dose-dependent manner and induced apoptosis. It also effectively inhibited cell proliferation, migration, and invasion, as well as suppressed angiogenic activity in conditioned media. Furthermore, 5-ALA PDT downregulated the expression of COL1A1 and PDGFRB, key genes in DFSP pathogenesis. CONCLUSIONS: The findings provide the first evidence of 5-ALA PDT's in vitro anti-tumor efficacy against DFSP, suggesting its potential as a novel therapeutic approach for DFSP. Further studies are warranted to explore the clinical utility of 5-ALA PDT in preventing DFSP recurrence.

Dermatofibrosarcoma protuberans of the breast.

Dermatofibrosarcoma protuberans (DFSP) of the breast is an infrequent soft tissue sarcoma that usually affects young to middle-aged women. Our case report describes a unique occurrence of DFSP of the breast in an adolescent girl, which was initially being managed as a keloid for 2 years under dermatology despite being refractory to treatment. Once the diagnosis of DFSP was confirmed through punch biopsy, our patient underwent surgical excision of the lesion under general anaesthesia. Our patient was at an increased risk of damage to the ductal system due to proximity of the lesion to the nipple-areolar complex, warranting the need for early recognition and treatment. As demonstrated by our case, DFSP of the breast can be difficult to diagnose since it resembles a range of benign and malignant pathologies of the breast.

Multiple primary dermatofibrosarcoma protuberans tumors in a single patient with chromosomal microarray analysis: A case report and review.

Dermatofibrosarcoma protuberans (DFSP) is a cutaneous sarcoma with a high propensity for local invasion and recurrence. Although it is a rare event, the occurrence of multiple tumors in a single patient raises a diagnostic dilemma, as metastatic disease should be differentiated from multiple primary malignant events. In more than 90% of DFSP, a pathogenic t(17;22) translocation leads to the expression of COL1A1::PDGFB fusion transcripts. Karyotype analysis, fluorescence in situ hybridization, and RT-PCR can be useful ancillary studies in detecting this characteristic rearrangement, and sequencing of the fusion transcript can be used to support a clonal origin in metastatic and multifocal disease. However, previous reports have demonstrated variable sensitivity of these assays, in part due to the high sequence variability of the COL1A1::PDGFB fusion. Here, we report a patient who developed two distinct DFSP tumors over the course of 7 years. Chromosomal microarray analysis identified distinctive genomic alterations in the two tumors, supporting the occurrence of multiple primary malignant events.

Conventional and contrast-enhanced ultrasound in the differential diagnosis of recurrent dermatofibrosarcoma protuberans and postoperative scar.

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) has a high recurrence rate after resection. Because of the lack of specific manifestations, recurrent DFSP is easily misdiagnosed as post-resection scar. A few series have reported ultrasound findings of recurrent DFSP; moreover, the usefulness of contrast-enhanced ultrasound in differentiating recurrent DFSP has not been studied. OBJECTIVE: We investigated conventional and contrast-enhanced ultrasound in the differential diagnosis of recurrent DFSP and post-resection scar. METHODS: We retrospectively evaluated the findings of conventional and contrast-enhanced ultrasound in 34 cases of recurrent DFSP and 38 postoperative scars examined between January 2018 and December 2022. RESULTS: The depth and vascular density of recurrent DFSP were greater than those of postoperative scars (P < 0.05). On gray-scale ultrasound, recurrent DFSP lesions were more commonly irregular, heterogeneous, and hypoechoic, with finger-like projections and ill-defined borders. Postoperative scar was more likely to appear as hypoechoic and homogeneous with well-defined borders (P < 0.05). On color Doppler ultrasound, recurrent DFSP was more likely to feature rich arterial and venous blood flow, and postoperative scar was more likely to display poor blood flow (P < 0.05). On contrast-enhanced ultrasound, recurrent DFSP was more likely to feature heterogeneous hyper-enhancement, and postoperative scar was more likely to display homogeneous iso-enhancement (P < 0.05). Recurrent DFSP presented a higher peak and sharpness than postoperative scar (P < 0.05). CONCLUSION: Conventional and contrast-enhanced ultrasound produced distinct features of recurrent DFSP and post-resection scar, which could improve the accuracy of differential diagnosis.

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors.

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

Incidence and survival rates of primary cutaneous malignancies in Korea, 1999-2019: A nationwide population-based study.

Primary cutaneous malignancies are among the most commonly diagnosed types of cancer worldwide. We aimed to examine the incidence and 5-year survival rates of all types of primary cutaneous malignancies in the Korean population. Data from the Korean Nationwide Cancer Registry from 1999 to 2019 were analyzed. The crude incidence rates, age-standardized incidence rates, and 5-year relative survival rates of each type of skin cancer were calculated. A total of 89 965 patients were diagnosed with primary cutaneous malignancies, which was a 7-fold increase from 1999 to 2019. The age-standardized incidence rates increased 3.4-fold in basal cell carcinoma (3.7/100 000 person-years), 2.0-fold in squamous cell carcinoma (1.6/100 000 person-years), 12.0-fold in Bowen disease (1.2/100 000 person-years), and 1.8-fold in malignant melanoma (0.7/10 000 person-years) in 2019. Average annual percentage changes in age-standardized incidence rates were statistically significant in basal cell carcinoma (15.8%), Bowen disease (5.8%), squamous cell carcinoma (5.1%), malignant melanoma (1.2%), melanoma in situ (1.1%), dermatofibrosarcoma protuberans (1.2%), mycosis fungoides (0.5%), primary cutaneous CD30+ T-cell proliferations (0.5%), adnexal and skin appendage carcinoma (0.4%), extramammary Paget's disease (0.2%), and Merkel cell carcinoma (0.2%). The 5-year relative survival rates were the highest in basal cell carcinoma (103.3%), followed by dermatofibrosarcoma protuberans (99.7%) and mycosis fungoides (96.6%), and lowest in angiosarcoma (24.7%). The 5-year relative survival rates steadily increased in extramammary Paget's disease (23.6%), cutaneous B-cell lymphoma (21.3%), mycosis fungoides (20.2%), extranodal NK/T-cell lymphoma, nasal type (18.1%), and malignant melanoma (16.1%) from 1996-2000 to 2015-2019. Most primary cutaneous malignancies have increased in incidence and survival rates in the Korean population, but to varying extents depending on the type of skin cancer.

Myxoid neurofibroma masquerading as lymphatic-venous malformation and poses a diagnostic challenge on fine needle aspiration biopsy.

BACKGROUND: Myxoid neurofibromas (NF) are uncommon, benign spindle cell tumors that originate from peripheral nerve sheaths, often posing a diagnostic challenge due to their hypocellularity on cytology specimens. Distinguishing myxoid spindle cell lesions can be challenging, given the broad range of potential differential diagnoses. CASE PRESENTATION: A 26-year-old female with a past medical history of embolized inguinal, flank, and retroperitoneal venolymphatic malformation presented with a left pelvic pain causing significant disability. CT scan showed an extensive 8.7 cm × 6.6 cm retroperitoneal mass. FNA was performed and alcohol-fixed papanicolaou-stained smears showed a hypocellular specimen with loosely arranged clusters of bland spindle cell proliferation in the background of a mucoid matrix. Spindle cells showed scant cytoplasm and elongated oval-shaped regular nuclei. Prominent nucleoli were not seen. An excisional biopsy revealed a bland spindle cell proliferation in a myxoid background associated with shredded collagen bundles. Immunohistochemical staining showed diffuse positivity for S100 and CD34. Based on the overall findings, a definitive diagnosis of myxoid neurofibroma was rendered. DISCUSSION: Cytological features of myxoid neurofibroma include the presence of hypocellular spindle-shaped cells arranged in small, loosely organized groups within a myxoid matrix background. Cells exhibit scant cytoplasm with regular oval and elongated nuclei. Nucleoli are typically not identified. The differential diagnosis includes myxoid neurofibroma, myxoma, myxoid liposarcoma, myxoid chondrosarcoma, myxoid dermatofibrosarcoma protuberans, low-grade fibromyxoid sarcoma, and low-grade myxo-fibrosarcoma. CONCLUSION: We aim to highlight the importance of considering myxoid neurofibroma in the differential diagnosis of hypocellular myxoid spindle cell lesions encountered on fine-needle aspiration cytology.

Establishment and characterization of NCC-DFSP5-C1: a novel patient-derived dermatofibrosarcoma protuberans cell line.

Dermatofibrosarcoma protuberans (DFSP) is the most prevalent dermal sarcoma, characterized by the presence of the fusion of the collagen type I alpha 1 (COL1A1) gene with the platelet-derived growth factor beta chain (PDGFB) gene. Although PDGF receptor inhibitor imatinib mesylate was approved for the treating patients with unresectable or metastatic DFSP, disease progression was shown in 9.2% of the patients. Therefore, developing novel therapeutic strategies is crucial for improving the prognosis of DFSP. Patient-derived cell lines play a vital role in preclinical studies; however, only a limited number of DFSP cell lines are currently available in public cell banks. Here, we successfully established a novel DFSP cell line (NCC-DFSP5-C1) using surgically resected tumor tissue from a patient with DFSP. NCC-DFSP5-C1 cells were confirmed to carry the COL1A1-PDGFB translocation and maintain the same mutation as the original tumor tissue. They exhibited consistent growth, formed spheroids, and were invasive. By screening a drug library using NCC-DFSP5-C1 and four previously established DFSP cell lines, we identified anti-cancer drugs that inhibit DFSP cell proliferation. Our observations suggest that the NCC-DFSP5-C1 cell line holds promise as a valuable tool for conducting fundamental and preclinical studies for DFSP.

Disease-Specific Mortality of Dermatofibrosarcoma Protuberans After Mohs Surgery Versus Wide Local Excision: A Systematic Review and Meta-Analysis.

BACKGROUND: Although advances have been made in the understanding of recurrence patterns in dermatofibrosarcoma protuberans, the current understanding of disease-specific mortality after surgical management is limited. OBJECTIVE: To understand disease-specific mortality rates associated with dermatofibrosarcoma protuberans treated with wide local excision (WLE) versus Mohs micrographic surgery (MMS). MATERIALS AND METHODS: A systematic literature search was conducted on March 6, 2023, to identify patients treated with MMS or WLE for dermatofibrosarcoma protuberans. RESULTS: A total of 136 studies met inclusion criteria. Overall, the disease-specific mortality rate was not significantly different after treatment with MMS (0.7%, confidence interval [CI] 0.1-1.2, p : 0.016) versus WLE (0.9%, CI 0.6-1.2, p < .001). For recurrent tumors, the MMS treatment group had a statistically significantly lower disease-specific mortality rate (1.0%, CI 0.0-2.0, p 0.046) compared with the WLE treatment group (3.5%, CI 2.0-5.1, p < .001). The mean follow-up for all studies was 57.6 months. CONCLUSION AND RELEVANCE: The authors' meta-analysis suggests there is no substantial difference in disease-specific mortality between MMS and WLE in patients with dermatofibrosarcoma protuberans, except in the case of recurrent tumors, where MMS seems to confer a survival advantage.

A case report of abdominal metastatic dermatofibrosarcoma protuberans misdiagnosed as gastrointestinal stromal tumor.

Dermatofibrosarcoma protuberans (DFSP) is a low-grade malignant soft-tissue tumor that originates from the skin. It has a slow onset in the early stages, non-specific clinical symptoms, low specificity, and can easily be overlooked, missed, or misdiagnosed by clinicians and pathologists. In addition, DFSP is prone to recurrence after local surgical treatment; however, distant metastasis, especially abdominal metastasis, is rare, which is also a challenge for the accurate diagnosis of DFSP when it progresses distantly. Now a case of abdominal metastasis of DFSP is reported. The patient has been treated with imatinib for ten years, and the lesion has shrunk, but because the patient has been receiving imatinib treatment, his abdominal lesion was once misdiagnosed as gastrointestinal stromal tumor. Therefore, we report on this case to enhance the understanding of the diagnosis and treatment of DFSP, and to provide reference for the pathological diagnosis and precise treatment of such patients.

Dermatofibrosarcoma Protuberans: A Study of 148 Patients.

INTRODUCTION: Dermatofibrosarcoma protuberans (DFSP) is the most common sarcoma of the skin. Although distant metastases are infrequent, DFSP is highly aggressive locally with frequent local recurrences. It has been reported that the presence within the tumour of areas histopathologically mimicking fibrosarcoma may increase the risk of recurrence. OBJECTIVE: The objective of this study was to review the clinical features of our patients with DFSP and the factors associated with recurrence of the tumour, focussing on the presence of fibrosarcomatous areas. METHODS: Retrospective study of patients with DFSP diagnosed in 1990-2021 in a tertiary university hospital. The medical records were reviewed to obtain the following data: age, sex, tumour location, diameter, evolution time, presence of fibrosarcomatous areas, development of recurrence, and follow-up. Factors possibly associated with disease-free survival were analysed with Kaplan-Meier method and multivariate Cox regression. RESULTS: 148 patients (74 women/74 men, mean age 46.28 years, SD 14.431) were included in the study. Tumours involved the head and neck in 15 cases, thorax in 31, abdomen in 16, upper back in 43, lower back in 10, upper extremities in 10, and lower extremities in 23. Fibrosarcoma-like areas were observed in 16 tumours (10.81%). In 17 patients (11.49%), recurrences were observed (13 local recurrences, 3 lung metastasis, and 1 local recurrence with lung metastasis). Fibrosarcomatous DFSP recurred more frequently than classic DFSP (50% vs. 6.82%, respectively), and its disease-free survival was significantly lower (p < 0.001). In multivariate Cox regression, the presence of fibrosarcomatous areas was the only factor influencing disease-free survival. CONCLUSIONS: It is important to identify the fibrosarcomatous variant since it recurs more frequently and has lower recurrence-free survival. Distant metastases, mainly in the lung, are also more frequent in fibrosarcomatous DFSP.

COL1A1::PDGFB fusion-associated uterine fibrosarcoma: A case report and review of the literature.

BACKGROUND: Mesenchymal neoplasms of the uterus encompass a diverse group of tumors, with varying characteristics and origins, collectively accounting for 8% of uterine malignancies. The most common variants include uterine leiomyosarcoma, low-grade and high-grade endometrial stromal sarcoma, adenosarcoma, and undifferentiated sarcoma. Clinical presentation is often nonspecific and can lead to delayed diagnosis. Uterine sarcomas are generally aggressive, resulting in poorer prognosis compared to carcinomas. Recent advances in molecular techniques, such as next-generation sequencing (NGS), have led to the identification of new subtypes of uterine sarcomas, including COL1A1::PDGFB fusion-associated fibrosarcoma, which has a specific chromosomal translocation t(17;22)(q22;q13). Imatinib, a tyrosine kinase inhibitor (TKI), is an effective treatment for dermatofibrosarcoma protuberans (DFSP), marked by this translocation. CASE: We present the case of a 42-year-old woman diagnosed with COL1A1::PDGFB fusion-associated uterine fibrosarcoma. The patient underwent total hysterectomy and excision of the tumor, initially misdiagnosed as a low-grade leiomyosarcoma. Subsequent histological examination, immunohistochemistry, and fluorescence in situ hybridization (FISH) confirmed the diagnosis. After 10 months, disease recurrence was detected, and Imatinib therapy was initiated at a dose of 400 mg daily. An allergic reaction led to a temporary discontinuation, but upon resumption with appropriate medication, a positive radiological response was observed. The patient achieved a complete remission after 2 years and is still on Imatinib treatment. CONCLUSIONS: COL1A1::PDGFB fusion-associated uterine fibrosarcoma is an extremely rare mesenchymal neoplasm. In a case we present herein, we treated a patient with imatinib as first-line medical therapy. The patient is currently in complete remission after 37 months from treatment start. To the best of our knowledge, this represents a unique observation. We also provide a detailed literature review of the published cases so far. Prospective case series are needed to further understand the natural history of these tumors and optimize treatment strategies.

Integrating vascularity into the pattern classification of pilomatricomas on ultrasound provides a more competent approach for discriminative evaluation.

BACKGROUND: Pilomatricoma has various manifestations on color Doppler ultrasound, and a differential diagnosis is challenging. The objective of this study was to investigate which characteristics of skin lesions on color Doppler ultrasound are effective in distinguishing pilomatricoma from epidermoid cyst and dermatofibrosarcoma protuberans. MATERIALS AND METHODS: Records of patients with pilomatricomas (n = 63), epidermoid cysts (n = 76), and dermatofibrosarcoma protuberans (n = 19) who underwent color Doppler ultrasound evaluation and surgical excision were reviewed. The anatomical distribution and color Doppler ultrasound characteristics of these lesions were analyzed. The 63 pilomatricomas were categorized into five types based on their color Doppler ultrasound characteristics, and the roles of these five types in the differential diagnosis of the aforementioned diseases were studied. RESULTS: Pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans exhibited some similar characteristics. Dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity were the major characteristics of pilomatricomas. The pilomatricomas could be categorized into five types, with type II having a diagnostic performance of sensitivity of 65.08%, specificity of 98.95%, area under the receiver operating characteristic curve (AUC) of 0.743, positive predictive value of 97.62%, and negative predictive value of 81.03% for the diagnosis of the aforementioned skin diseases. CONCLUSION: A combination of dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity exhibits higher diagnostic performance for the differential diagnosis of pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans.

Subtotal Thigh Flap for Large Abdominal Wall Defect Reconstruction in Patient With Recurrent Dermatofibrosarcoma Protuberans: A Case Report and Literature Review.

BACKGROUND: Harvesting an adequate-sized flap is challenging for reconstructing large defects on the abdominal wall. A subtotal thigh flap would be one of the choices as it provides a well-vascularized large flap with muscle components. Moreover, dermatofibrosarcoma protuberans (DFSP) is a low-grade dermal neoplasm with a high recurrence rate. There is still no consensus on the extent of resection to prevent a recurrence. OBJECTIVES: We present a case of a patient who underwent the reconstruction of a large abdominal wall defect with a subtotal thigh flap after the resection of recurrent DFSP. MATERIALS AND METHODS: A 59-year-old man killed from a recurrent huge mass in the lower abdomen with an invasion of the small intestine. His baseline characteristics and records of operations, medications, and outcomes were reviewed. RESULT: After tumor excision, a 28 × 30-cm subtotal thigh flap was harvested from his left thigh to reconstruct the abdominal defect. A microvascular anastomosis with left deep inferior epigastric vessels was made eventually. The flap was in good condition, and the donor site was covered with a split-thickness skin graft. CONCLUSIONS: Subtotal thigh flap may be considered for large abdominal wall defect reconstruction as it allows good perfusion of relatively large skin paddles compared with other free flaps. Also, patients with DFSP need definite margin-free resection and close follow-up to prevent a recurrence.

Survival outcomes of rare cutaneous malignancies within an insured cohort of patients, 1988-2018.

BACKGROUND: There are limited survival data on cutaneous angiosarcoma (CAS), dermatofibrosarcoma protuberans (DFSP), Merkel cell carcinoma (MCC), and sebaceous carcinoma (SC). OBJECTIVE: To analyze survival trends in CAS, DFSP, MCC, and SC among a racially diverse, insured cohort of patients. METHODS: Using data from the Kaiser Permanente Southern California Cancer Registry, we identified adults diagnosed with CAS, DFSP, MCC, or SC between January 1, 1988 and December 31 2018, followed through December 31, 2021. RESULTS: Our cohort consisted of 83 diagnoses of CAS, 490 diagnoses of DFSP, 411 diagnoses of MCC, and 249 diagnoses of SC. Our analysis revealed no significant differences in overall or disease-specific 1000 person-years mortality rates among our populations of non-Hispanic Whites, Hispanics, African American/Blacks, and Asian American/Pacific Islanders diagnosed with CAS, DFSP, MCC, or SC. On multivariate analysis, controlling for patient and tumor characteristics, there was similarly no increased risk of overall mortality for minorities diagnosed with CAS, DFSP, MCC, or SC. LIMITATIONS: Retrospective nature of the analysis and small sample size. CONCLUSION: Contrary to existing literature, our results show a notable lack of racially driven survival disparities among insured individuals with CAS, DFSP, MCC, and SC, emphasizing the importance of health care coverage.