S1 guidelines for dermatofibrosarcoma protuberans (DFSP) - update 2018

A novel method of assessing intraoperative surgical margins in patients with dermatofibrosarcoma protuberans: A specimen radiography system

Background Dermatofibrosarcoma protuberans (DFSP) is one of the most challenging cutaneous cancers in surgical clinic practice. Excision with negative margins is essential for effective disease control. However, wide surgical margins and maximal tissue conservation are mutually exclusive. Mohs micrographic surgery conserves tissue but is time-consuming. Thus, we developed a novel specimen radiography system that can be used intraoperatively. Aims To introduce a specimen radiography system for evaluating intraoperative surgical margins in patients with dermatofibrosarcoma protuberans. Methods Since September 2017, we have treated seven biopsy-proven cases of local DFSPs via local excision with surgical margins of 2-4 cm. During operations, the operative specimens were screened using the specimen radiography system. All surgical specimens were pathologically examined intraoperatively. Results Five patients were men and two were women, of median age 36 years. The mean radiographic screening time was 9.7 ± 2.3 min. Radiographically negative margins were confirmed intraoperatively. The minimal margin width ranged from 5.0 to 35.4 mm (mean width 16.9 ± 10.4 mm). The intraoperatively negative radiographic margins were consistent with those revealed by postoperative pathology. The minimal pathological margin width ranged from 4.0 to 34.5 mm (mean 16.6 ± 10.1 mm) and was not significantly different from the intraoperative data. Limitations The sample size was small and positive or negative predictive values were not calculated. Conclusions We introduce a novel method of intraoperative surgical margin assessment for DFSP patients. It may find broad clinical and research applications during oncoplastic surgery.

Progressive insights into fibrosarcoma diagnosis and treatment: leveraging fusion genes for advancements

Fibrosarcoma, originating from fibroblast cells, represents a malignant neoplasm that can manifest across all genders and age groups. Fusion genes are notably prevalent within the landscape of human cancers, particularly within the subtypes of fibrosarcoma, where they exert substantial driving forces in tumorigenesis. Many fusion genes underlie the pathogenic mechanisms triggering the onset of this disease. Moreover, a close association emerges between the spectrum of fusion gene types and the phenotypic expression of fibrosarcoma, endowing fusion genes not only as promising diagnostic indicators for fibrosarcoma but also as pivotal foundations for its subcategorization. Concurrently, an increasing number of chimeric proteins encoded by fusion genes have been substantiated as specific targets for treating fibrosarcoma, consequently significantly enhancing patient prognoses. This review comprehensively delineates the mechanisms behind fusion gene formation in fibrosarcoma, the lineage of fusion genes, methodologies employed in detecting fusion genes within fibrosarcoma, and the prospects of targeted therapeutic interventions driven by fusion genes within the fibrosarcoma domain.

Survival Outcomes of Mohs Surgery versus Wide Local Excision for Less Common Nonmelanoma Skin Cancers: A Stabilized Inverse Probability of Treatment Weighting Analysis

BACKGROUND

Compared with wide local excision (WLE), Mohs micrographic surgery (MMS) can not only remove the tumor tissue but also ensure a negative margin. However, there is limited evidence on whether there is a difference in prognosis between the two techniques for less common nonmelanoma skin cancers (NMSCs).

OBJECTIVES

The aim of our study was to compare the survival outcomes of MMS and WLE for less common NMSCs.

METHODS

This study retrospectively analyzed data from the Surveillance, Epidemiology, and End Results dataset between 2003 and 2018. The less common NMSCs include Merkel cell carcinoma, skin appendage neoplasm, fibromatous malignancy, and other rare NMSCs. The stabilized inverse probability of treatment weighting (SIPTW) and the Kaplan-Meier methods were adopted to assess the overall survival (OS) and cancer-specific survival (CSS). Furthermore, the Cox proportional hazards, Fine-and-Gray regression analysis, and subgroup analysis models were applied to examine the effects of MMS versus WLE based on all-cause and cancer-specific mortality.

RESULTS

We identified 6,582 individuals with less common NMSCs for survival analysis, among which 1,946 patients (29.5%) had undergone MMS and 4,636 (70.5%) had received WLE. Diseases diagnosed in the most recent year, older age, the White race, married status, eyelid/face site, small tumor size, and localized disease were factors significantly associated with MMS treatment. Compared with the WLE group, the MMS group had comparable OS before and after the SIPTW analysis. Additionally, after adjusting for other confounding covariates, the surgery type (WLE vs. MMS) did not show significant associations with all-cause mortality (hazard ratio [HR]: 1.03, 95% confidence interval [CI]: 0.94-1.14, p = 0.517) and disease-specific mortality (HR: 1.16, 95% CI: 0.95-1.42, p = 0.134). Moreover, the subgroup analysis validated these findings.

CONCLUSION

MMS and WLE have comparable OS and CSS for less common NMSCs.

Modified low-dose second window indocyanine green technique improves near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection: A randomized control trial

Objective

Conventional second window indocyanine green (SWIG) technique has been widely attempted in near-infrared fluorescence (NIRF) imaging for intraoperative navigation of tumor radical resection. Nevertheless, the overuse of indocyanine green (ICG) led to an increased risk of drug lethal allergy and high medical cost. This prospective study was to explore clinical application of modified low-dose SWIG technique in guiding dermatofibrosarcoma protuberans (DFSPs) radical resection.

Method

Patients with DFSPs were randomly assigned to control and experimental group. The ICG was injected intravenously 24 h before surgery, at a dose of 3.5 mg/kg in the control group and 25 mg/patient in the experiment group, respectively. Intraoperative NIRF imaging included serial views of gross tumor, tumor bed and cross-sectional specimen.

Results

Although NIRF imaging of gross tumor and tumor bed in the experimental group demonstrated similar sensitivity and negative predictive value, the specificity and positive predictive value were obviously higher compared to control group. The tumor-to-background ratios of cross-sectional specimens in the experimental group was significantly higher than in the control group (P = 0.000). Data in both groups displayed that there was a positive correlation of tumor size in cross-sections between integrated histopathologic photomicrographs and NIRF imaging of specimen views (P = 0.000). NIRF imaging of cross-sectional specimens had a significant decrease in time cost, and an increase in the ability of examining more surgical margins (P = 0.000).

Conclusion

This is the first study to demonstrate that a low-dose SWIG technique could improve the accuracy of near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection.

Clinical Trial Registration: ChiCTR2100050174; date of registration: August 18, 2021 followed by “retrospectively registered”

Comprehensive analysis of transcriptome characteristics and identification of TLK2 as a potential biomarker in dermatofibrosarcoma protuberans

Background: Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma characterized by local invasion and recurrence. RNA sequencing (RNA-seq) allows the qualification of cellular RNA populations and provides information on the transcriptional state. However, few studies have comprehensively analyzed DFSP transcriptional data.

Methods: Fourteen DFSP samples with paired non-neoplastic soft tissue from Chinese patients undergoing Mohs micrographic surgery were used for RNA-seq analysis. Differential expression analysis and enrichment analysis for RNA-seq data were performed to identify fusion genes, biomarkers, and microenvironment characteristics of DFSP.

Results: This study systemically describes the transcriptomic characteristics of DFSP. First, we performed gene fusion analysis and identified a novel FBN1-CSAD fusion event in a DFSP patient with fibrosarcomatous transformation. Then, we identified TLK2 as a biomarker for DFSP based on functional enrichment analysis, and validated its accuracy for diagnosing DFSP by immunohistochemical staining and joint analysis with public data. Finally, microenvironment analysis described the infiltration characteristics of immune and stromal cells in DFSP.

Conclusion: This study demonstrates that RNA-seq can serve as a promising strategy for exploring molecular mechanisms in DFSP. Our results provide new insights into accurate diagnosis and therapeutic targets of DFSP.

A Multidisciplinary Approach to Complex Dermal Sarcomas Ensures an Optimal Clinical Outcome

Primary dermal sarcomas (PDS) belong to a highly clinically, genetically and pathologically heterogeneous group of rare malignant mesenchymal tumours primarily involving the dermis or the subcutaneous tissue. The tumours are classified according to the mesenchymal tissue from which they originate: dermal connective tissue, smooth muscle or vessels. Clinically, PDS may mimic benign soft tissue lesions such as dermatofibromas, hypertrophic scarring, etc. This may cause substantial diagnostic delay. As a group, PDS most commonly comprises the following clinicopathological forms of dermal sarcomas: dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX), dermal undifferentiated pleomorphic sarcoma (DUPS), leiomyosarcoma (LMS), and vascular sarcomas (Kaposi’s sarcoma, primary angiosarcoma, and radiation-induced angiosarcoma). This clinical entity has a broad spectrum regarding malignant potential; however, local aggressive behaviour in some forms causes surgical challenges. Preoperative, individualised surgical planning with complete free margins is pivotal along with a multidisciplinary approach and collaboration across highly specialised surgical and medical specialties. The present review gives a structured overview of the most common forms of dermal sarcomas including surgical recommendations and examples for advanced reconstructions as well as the current adjunctive medical treatment strategies. Optimal aesthetic and functional outcomes with low recurrence rates can be achieved by using a multidisciplinary approach to complex dermal sarcomas. In cases of extended local tumour invasion in dermal sarcomas, advanced reconstructive techniques can be applied, and the interdisciplinary microsurgeon should be an integral part of the sarcoma board.

Risk factors related to postoperative recurrence of dermatofibrosarcoma protuberans: A retrospective study and literature review

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a rare low-grade malignant soft tissue tumor characterized by rosette-like infiltrative growth. Postoperative recurrence of this tumor is very common.

AIM

To evaluate the risk factors related to recurrence after wide local excision (WLE) of DFSP and to guide clinical diagnosis and treatment.

METHODS

The medical records of 44 DFSP patients confirmed by pathology at our hospital from 2012 to 2019 were retrospectively reviewed. The relationship between clinical features, tumor characteristics, treatment, and recurrence risk were analyzed, and the possible risk factors for postoperative tumor recurrence were evaluated.

RESULTS

There were 44 patients in total, including 21 males and 23 females. The median progression free survival was 36 mo (range, 1-240 mo). Twenty patients were treated for the first time, while 24 had previous treatment experience. Forty-two cases were followed for 25.76 ± 22.0 mo, among whom four (9.52%) experienced recurrence after WLE (rate was 9.52%). The recurrence rate in the recurrent group was higher than that in the patients with primary tumor (19.05% vs 0%, P = 0.028). Eighteen cases had a history of misdiagnosis (rate was 40.91%). The recurrence rate among patients with previous experience of misdiagnosis was significantly higher than in patients without (68% vs 36.84%, P = 0.04). The tumor diameter in patients with a history of treatment was larger than in patients treated for the first time (4.75 ± 0.70 cm vs 2.25 ± 0.36 cm, P = 0.004).

CONCLUSION

To sum up, the clinical manifestations of DFSP are not specific and are easily misdiagnosed, thus commonly causing the recurrence of DFSP. After incomplete resection, the tumor may rapidly grow. Previous recurrence history may be a risk factor for postoperative recurrence, and tumor location may have an indirect effect on postoperative recurrence; however, we found no significant correlation between sex, age, course of the disease, or tumor size and postoperative recurrence.

Atrophic Pigmented Dermatofibrosarcoma Protuberans: A Case Report and Literature Review

Dermatofibrosarcoma protuberans (DFSP) is a rare soft tissue sarcoma characterized by the proliferation of spindle cells arranged in a storiform pattern. Here we report a case of DFSP presenting as a bluish-black atrophic plaque. The tumor had the histopathologic characteristics of both the pigmented and atrophic variants of DFSP. We describe the histopathologic, molecular, and imaging features of this patient and review other cases of DFSP that have been reported in the literature. Early identification of this DFSP variant can help clinicians implement clinical management strategies to prevent recurrence.

Mohs micrographic surgery: a review of indications, technique, outcomes, and considerations

Mohs micrographic surgery is a specialized form of skin cancer surgery that has the highest cure rates for several cutaneous malignancies. Certain skin cancers can have small extensions or “roots” that may be missed if an excised tumor is serially cross-sectioned in a “bread-loaf” fashion, commonly performed on excision specimens. The method of Mohs micrographic surgery is unique in that the dermatologist (Mohs surgeon) acts as both surgeon and pathologist, from the preoperative considerations until the reconstruction. Since Dr. Mohs’s initial work in the 1930s, the practice of Mohs micrographic surgery has become increasingly widespread among the dermatologic surgery community worldwide and is considered the treatment of choice for many common and uncommon cutaneous neoplasms. Mohs micrographic surgery spares the maximal amount of normal tissue and is a safe procedure with very few complications, most of them managed by Mohs surgeons in their offices. Mohs micrographic surgery is the standard of care for high risks basal cell carcinomas and cutaneous squamous cell carcinoma and is commonly and increasingly used for melanoma and other rare tumors with superior cure rates. This review better familiarizes the dermatologists with the technique, explains the difference between Mohs micrographic surgery and wide local excision, and discusses its main indications.

Dermatofibrosarcoma protuberans in a young patient with epidermolysis bullosa: a case report

Background

Epidermolysis bullosa is a group of rare inherited skin diseases characterized by blister formation following mechanical skin trauma. Epidermolysis bullosa is associated with increased skin cancer rates, predominantly squamous cell carcinomas, yet to our best knowledge, there is no reported case of dermatofibrosarcoma protuberans in a patient with Epidermolysis bullosa.

Case presentation

Here, we present a 26-year-old man with junctional epidermolysis bullosa, who developed a DFSP on the neck. Initial, the skin alteration was mistakenly not considered malignant, which resulted in inadequate safety margins. The complete resection required a local flap to close the defect, which is not unproblematic because of the chronic inflammation and impaired healing potential of the skin due to Epidermolysis bullosa.

Conclusions

To our best knowledge, this is the first reported case of a skin-associated sarcoma in a patient with EB; however, further investigation is required to verify a correlation.

A Rare Malignant Disease, Dermatofibrosarcoma Protuberans of the Breast: A Retrospective Analysis and Review of Literature

Dermatofibrosarcoma protuberans (DFSP) is a rare low-grade fibroblastic mesenchymal tumor derived from the dermis. The aim of this retrospective analysis was to summarize the clinicopathological data from our cases and published cases to offer more evidence for the recognition of dermatofibrosarcoma protuberans (DFSP). A total of 6 breast DFSP patients who had received treatment in our hospital were retrospectively enrolled, and detailed clinicopathological data were gathered for analysis. The median age was 29.5 years (ranging from 17 to 42 years). Most cases presented a red or brown-red, mobile, well-circumscribed, protruding, breast mass (ranging from 1 to 3 cm). For histopathology, all cases (6/6) showed a storiform pattern of spindle cells that were positive for CD34 (6/6) and Vimentin (5/6) and negative for smooth muscle actin (0/6) and S-100 protein (0/6). The majority of patients (5/6) underwent wide local excision, with 2 cases treated with radiotherapy. With a median follow-up of 36 months, all 6 patients survived without recurrence or metastasis. The PubMed database was used to search for similar cases. Eventually, 36 cases were included in this review, while cases without detailed clinical information or not reported in English were excluded from the analysis. To summarize, DFSP of the breast is an extremely rare malignancy characterized by spindle tumor cells arranged in a storiform pattern and positivity for CD34. The core needle biopsy is one of the crucial methods for its preoperative diagnosis. Management of DFSP is mainly based on surgical excision. It is prone to local recurrence, so long-term follow-up is required.

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.

Resection and Reconstructive Options in the Management of Dermatofibrosarcoma Protuberans of the Head and Neck

Objective To discuss resection and various reconstructive options in patients with dermatofibrosarcoma protuberans (DFSP). Methods This study was conducted at Shifa International Hospital, Islamabad, Pakistan, from May 2018 to December 2019. All patients aged 20 years or above of either gender who were diagnosed to have DFSP over this period were included in the study. All the patients underwent wide local excision of the tumor under general anesthesia. A peroperative frozen section was conducted in all the cases to confirm complete excision. Immediate reconstruction was performed following the tumor excision. The choice of reconstruction, i.e. free, regional, or local flap was based on the size of the resultant defect. Results The mean age of the patients was 37.11 ±10.91 years. There were 12 (66.7%) males and six (33.3%) females. The mean duration of the disease was 11.22 ±2.94 months. The affected anatomical site showed that the face was involved in the majority, nine (50%) patients, followed by the scalp in four (22.2%), nape of the neck in three (16.7%), and supraclavicular region in two (11.1%) patients. In most of the cases, the free flap was observed, i.e. (n=9, 50%), followed by a regional flap in seven (38.9%), and the local flap in two (10.1%) patients. Conclusion Wide local excision of the disease, confirmed on frozen section, offers improved survival. Among DFSP of the head and neck, the face was found to be the affected anatomical site in half the cases. Also, reconstruction following tumor excision with a free flap is the most favorable option among patients with DFSP.