Adequate surgical margins for dermatofibrosarcoma protuberans - A multi-centre analysis

Progress in histology specific treatments in soft tissue sarcoma

INTRODUCTION

Soft tissue sarcomas (STS) represent a heterogenous group of rare tumors, primarily treated with surgery. Preoperative radiotherapy is often recommended for extremity high-risk STS. Neoadjuvant chemotherapy, typically based on doxorubicin with ifosfamide, has shown efficacy in limbs and trunk wall STS. Second-line chemotherapy, commonly utilized in the metastatic setting, is mostly histology-driven. Molecular targeted agents are used across various histologies, and although the use of immunotherapy in STS is still in its early stages, there is increasing interest in exploring its potential.

AREAS COVERED

This article involved an extensive recent search on PubMed. It explored the current treatment landscape for localized and metastatic STS, focusing on the combined use of radiotherapy and chemotherapy for both extremity and retroperitoneal tumors, and with a particular emphasis on the most innovative histopathology driven therapeutic approaches. Additionally, ongoing clinical trials identified via clinicaltrials.gov are included.

EXPERT OPINION

Recently there have been advancements in the treatment of STS, largely driven by the outcomes of clinical trials. However further research is imperative to comprehend the effect of chemotherapy, targeted therapy and immunotherapy in various STS, as well as to identify biomarkers able to predict which patients are most likely to benefit from these treatments.

UK guidelines for the management of soft tissue sarcomas

Soft tissue sarcomas (STS) are rare tumours arising in mesenchymal tissues and can occur almost anywhere in the body. Their rarity, and the heterogeneity of subtype and location, means that developing evidence-based guidelines is complicated by the limitations of the data available. This makes it more important that STS are managed by expert multidisciplinary teams, to ensure consistent and optimal treatment, recruitment to clinical trials, and the ongoing accumulation of further data and knowledge. The development of appropriate guidance, by an experienced panel referring to the evidence available, is therefore a useful foundation on which to build progress in the field. These guidelines are an update of the previous versions published in 2010 and 2016 [1, 2]. The original guidelines were drawn up by a panel of UK sarcoma specialists convened under the auspices of the British Sarcoma Group (BSG) and were intended to provide a framework for the multidisciplinary care of patients with soft tissue sarcomas. This iteration of the guidance, as well as updating the general multidisciplinary management of soft tissue sarcoma, includes specific sections relating to the management of sarcomas at defined anatomical sites: gynaecological sarcomas, retroperitoneal sarcomas, breast sarcomas, and skin sarcomas. These are generally managed collaboratively by site specific multidisciplinary teams linked to the regional sarcoma specialist team, as stipulated in the recently published sarcoma service specification [3]. In the UK, any patient with a suspected soft tissue sarcoma should be referred to a specialist regional soft tissues sarcoma service, to be managed by a specialist sarcoma multidisciplinary team. Once the diagnosis has been confirmed using appropriate imaging and a tissue biopsy, the main modality of management is usually surgical excision performed by a specialist surgeon, combined with pre- or post-operative radiotherapy for tumours at higher risk for local recurrence. Systemic anti-cancer therapy (SACT) may be utilised in cases where the histological subtype is considered more sensitive to systemic treatment. Regular follow-up is recommended to assess local control, development of metastatic disease, and any late effects of treatment.

Head-and-neck dermatofibrosarcoma protuberans: Survival analysis and Clinically relevant immunohistochemical indicators

BACKGROUND

Head and neck dermatofibrosarcoma protuberans (HNDFSP) is extremely rare and not entirely understood.

OBJECTIVE

To investigate the clinicopathological features of HNDFSP and identify the expression of its clinically relevant indicators, with the expectation of improving the existing treatment strategies.

METHODS

A long-term follow-up of patients with HNDFSP who received treatment between 2000 and 2021 at Shanghai Ninth People's Hospital was conducted. The clinical, histological, and immunohistochemical data of the patients were retrieved and analyzed. The endpoint of the study was the incidence of significant disease-related clinical events (recurrences or metastasis).

RESULTS

A total of 49 patients with HNDFSP were included in the study, with males (92.7%) predominating than females (7.3%). Eighteen patients developed recurrent disease (36.8%) after surgery, and the median time of recurrence was 48 months (interquartile, 20-74 months). Metastasis occurred in two cases (4.1%). Two patients died during follow-up, both with local recurrence, and one of them with intestinal metastasis. Post-operation radiotherapy was administered to eight patients (16.3%) and the effect in local control was remarkable. Age, tumor size, and negative margins with sufficient safety width were the main independent factors affecting the disease-free survival. Several potential targeted therapeutic indicators, including EZH2 (80.0%), EGFR (91.4%), PDGF (97.1%), PD-L1 (77.1%), and VEGF (77.1%), were positively expressed in most tumor samples.

CONCLUSION

HNDFSP is rare, significantly challenging to control locally, and has a worse prognosis with current treatment strategies. Wide local excision and long-term follow-up are needed. Radiotherapy could improve the prognosis of patients with HNDFSP.

Different sonographic presentations of dermatofibrosarcoma protuberans

BACKROUND

Dermatofibrosarcoma protuberans (DFSP) is a low-grade spindle cell sarcoma of fibroblastic origin. This tumor originates in the dermis and infiltrates the subcutaneous tissue. The highest incidence occurs in the third and fourth decades of life, affecting most frequently the trunk and proximal extremities. Ultrasound is performed in those cases where the clinical appearance of the lesion is not typical and when the physician wants to determine the extent and depth of the lesion.

MATERIAL AND METHODS

Retrospective analysis of the ultrasound and demographic findings of thirteen patients with DFSP.

RESULTS

13 patients, 8 females and 5 males, aged from 2 months to 58 years old. One patient with two different separated synchronous tumors. On ultrasonography they compromised the dermal hypodermal layers in 93% of the cases and 1 dermal lesion. The compromise reached the aponeurotic plane in two cases. The sized varied from 5 to 38 mm. They presented as a well-defined hypoechogenic nodule in seven cases (50%). In three cases (21%) they presented as a hypoechogenic infiltrate ill-defined border solid lesion; in two cases as a plaque ill-defined lesion, and two cases as a pseudonodular inflammatory lesion with irregular borders. All lesions appeared vascularized on color Doppler imaging.

CONCLUSION

DFSP is a low grade sarcoma of fibroblastic origin, that usually arises in the dermis and infiltrates the subcutaneous tissue. The clinical presentations are variable. On ultrasound we found different patterns: well-defined hypoechogenic solid nodule, hypoechogenic infiltrate ill-defined border solid lesion, plaque ill-defined lesion, and pseudonodular inflammatory lesion. It is important to know and recognize this suspicious different ultrasound presentations in order to recommend a histological study.

Incidence and Survival Outcomes of Dermatofibrosarcoma Protuberans From 2000 to 2020: A Population-Based Retrospective Cohort Analysis

BACKGROUND

Recent changes in the incidence and survival of dermatofibrosarcoma protuberans (DFSP) have not been described.

OBJECTIVE

To characterize the incidence and survival of DFSP.

MATERIALS AND METHODS

A retrospective cohort study of patients with DFSP from 2000 to 2020 in the Surveillance, Epidemiology, and End Results database was performed. Cox and Fine-Gray regression models were used to assess overall and DFSP-specific survival.

RESULTS

The incidence of DFSP has not changed from 2000 to 2020 with 4.6 cases/million person-years, with higher rates in dark-skinned and middle-age individuals. Factors associated with overall mortality in DFSP patients include advanced age ( p < .0001), male sex (hazard ratio [HR] 1.8, p < .0001), larger tumors (HR 1.002 per millimeter, p < .001), lower household income (HR 1.8, p = .0002), and lower extremity location (HR 1.7, p = .008). Mohs surgery is associated with improved overall survival (HR 0.4, p = .02). Large tumor size (6.0+ cm, HR 6.7, p = .01) and advanced age (age 80+ years, HR 21.3, p = .003) were associated with worse DFSP-specific mortality.

CONCLUSION

Dermatofibrosarcoma protuberans incidence has remained constant from 2000 to 2020. Increasing age and tumor size, decreased income, male sex, and lower extremity location are associated with worsened survival. Mohs surgery is associated with improved overall survival. Increased age and tumor size are associated with worsened DFSP-specific mortality.

Outcome of Surgical Management of Dermatofibrosarcoma Protuberance: A Single-Institution Multidisciplinary Approach

Introduction

Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing, and locally aggressive soft tissue tumor with a high recurrence rate and metastatic potential, even with the proper treatment.

Methods

This was a retrospective (case series) study that took place at King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia, to determine the outcomes of and appropriate margin excision for DFSP. All patients who were diagnosed with DFSP from 2016 to 2021 were included. The following variables were assessed: demographics, tumor characteristics, management options, and most importantly, whether patients were managed with an oncology-oriented approach or a non-oncology-oriented approach.

Results

There were a total of seventeen patients with DFSP, four of whom had fibrosarcomatous differentiation (FS-DFSP). The majority (N = 13, 76.5%) of the patients were females. The lower extremities and back were the most common locations for DFSP, accounting for 47.1% and 23.5%, respectively. Only two (11.76%) patients had metastatic disease, one of whom had FS-DFSP. The minimum resection margin was 3 cm, and the maximum was 5 cm. Thirteen (76.47%) patients were managed with an oncology-oriented approach (Group I), 23% of whom had post-excision positive margins. However, all patients who were managed with a non-oncology-oriented approach (Group II) had positive margins post-excision. More than three-quarters (76.9%) of group I underwent wide resection. Split-thickness skin grafting and primary closure were the most commonly used reconstruction methods in groups I and II, respectively. The mean planned margins in groups I and II were 3.9 cm and 1.7 cm, respectively.

Conclusion

The findings of this study suggest that a planned wide-margin excision with a minimum safe margin of 3-5 cm should be implemented to reduce the recurrence, metastasis, and need for further surgeries in patients with DFSP.

Cutaneous sarcoma: a review and practical approach to management

Sarcomas arising in the skin are rare but potentially fatal. These tumours originate from mesenchymal cells and can be divided between those that arise in soft tissue and those arising from bone. General guidelines exist for the management of soft-tissue sarcomas; however, there are no specific guidelines for cutaneous sarcomas. Current literature was reviewed for management of seven cutaneous sarcomas including atypical fibroxanthoma, pleomorphic dermal sarcoma, dermal and subcutaneous leiomyosarcoma, dermatofibroma sarcoma protuberans, Kaposi sarcoma, cutaneous angiosarcoma and malignant peripheral nerve sheath tumour. All suspected sarcomas should be discussed in a sarcoma multidisciplinary team meeting. This article is not a clinical guideline but should serve as a practical summary of how these tumours present, how they are recognized histologically, and how best to manage and follow-up patients. The aim is to support clinicians and facilitate the best and most evidence-based standard of care available.

Oncological efficiency of wide local excision in dermatofibrosarcoma protuberans

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a slow-growing, low- to intermediate-grade malignant sarcoma. Its optimal treatment is resection with wide margins; the likelihood of local control associated with this procedure exceeds 90%. The probability of regional or distant metastases is <5%.

OBJECTIVE

We examined the clinical, epidemiological, and pathological features, the treatment types, and outcomes of patients to investigate the width of safe surgical margins (SM) and how the width of SMs affected recurrence in DFSP.

METHODS

We retrospectively examined the records of 60 patients who were initially operated on with wide local excision for DFSP in the period 2008-2019. Optimal cutoff points for SMs were calculated with the receiver operating characteristic curve analysis and found as 1.925 cm histopathologically and 2.26 cm macroscopically.

RESULTS

During the mean 89.6-month follow-up, local recurrence was seen in 36.7% and distant metastasis in 20% of the patients. Recurrences were significantly related to peripheral resection margins. Analysis by histopathologic cutoff points showed that the local recurrence rate was 84% when SM was ≤1.925 cm, but only 2.85% when >1.925 cm (p = 0.002). Recurrence-free survival was 40.92 months when SM was ≤1.925 cm and 225.75 months when s >1.925 cm (p<0.001). Analysis by macroscopic cutoff points showed that the local recurrence rate was 95.5% when SM was ≤2.26 cm, but only 4% when >2.26 cm (p = 0.001). Recurrence-free survival was 43 months when SM was ≤2.26 cm and 222 months when >2.26 cm (p<0.001). In metastatic patients, progression-free survival was 9 months with cytotoxic chemotherapy, whereas 38.4 months with tyrosine kinase inhibitor (imatinib) (p = 0.002).

CONCLUSION

This study showed SMs >2.5 cm to be sufficiently safe for WLE and optimized the balance among safe margin width, reconstruction need, and surgical morbidity. In metastatic DFSP patients, tyrosine kinase inhibitor imatinib is more effective than cytotoxic chemotherapy for progression-free survival.

Reconstruction options in recurrent dermatofibrosarcoma protuberans:A scoping review

Background

This review will outline the evaluation, diagnosis, and management of dermatofibrosarcoma protuberans and emphasizes multidisciplinary role of nurses, plastic surgeons and radiation oncologist in this recurrent metastatic lesion. It pinpoints affected population at risk, clinical features, and reconstruction options. No analytical research has been done in this area.

Material and Methods

A scoping review of patients of DFSP who underwent reconstruction after excision of tumors was performed in the Department of Burn and Plastic Surgery, AIIMS Rishikesh. It used a five framework approach. A review of 85 similar cases reported in the literature have been scrutinized in relation to the reconstruction options, sites of the tumor, margins of excision and recurrence.

Results

85 full length English studies were included out of the 445 cases found in Pubmed and related search engines to reveal various reconstructive options in reconstruction of DFSP defects. Present scoping review identifies free anterolateral thigh flap to be useful in 7 review articles followed by propeller flaps in 3 isolated case reports. 2 cases of free latissimus dorsi flap were used for reconstruction of abdominal defects.

Conclusion

All patients should undergo a strict screening protocol where the health personnel can play a crucial role by educating parents on the follow up and report new lesions as early as possible. All operated tumor patients can be given safety tips and education on care and risks after reconstruction with skin flaps or skin grafting. A multidisciplinary approach between the surgeon, nurse and radiation oncologist is needed for effective management of these lesions.

Dermatofibrosarcoma protuberans surgery: Experiences of four African surgical oncology units and literature review

BACKGROUND AND OBJECTIVES

Dermatofibrosarcoma is a locally malignant tumor. This gives surgery a place of choice. The advent of imatinib has improved outcomes. Our aim is to describe the indications, techniques and results of surgery.

METHODS

A retrospective, multicenter, descriptive study conducted in four West African surgical oncology units. It covers dermatofibrosarcoma surgery performed between January 1, 1988 and December 31, 2020. We took into account the surgical procedure, the mode of skin coverage, adjuvant treatments and survival. Comparisons were possible using Student's t-test and Pearson's χ² .

RESULTS

We recorded 81 cases of dermatofibrosarcoma. Surgery was effective in 90.1% of cases. Wide resection was the principle with a mean resection margin of 3.8 ± 1.9 cm. healing by primary intention, flaps and healing by secondary intention were the methods of skin coverage in 30.1%, 24.7% and 41.1% respectively. The type of skin coverage was related to the topography and size of the tumor (p < 0.0001). The healing time is associated with the type of skin cover. The recurrence rate was not related to the type of skin coverage (p = 0.8).

CONCLUSIONS

Wide and deep resection in the absence of Mohs micrographic surgery ensures healthy margins. Oncoplasty reduces the healing time without increasing the risk of recurrence.

Evidence from Clinical Studies Related to Dermatologic Surgeries for Skin Cancer

Simple Summary

Although significant progress in pharmacotherapy for skin cancer has been made in the past several years, surgical removal of primary skin cancer is still the first choice of treatment unless distant metastases are evident. In the surgical treatment of primary skin tumors, the surgical margin is critical not only for reducing the possibility of tumor recurrence but also for minimizing the cosmetic and functional complications associated with wide local excision. In contrast, dermatologic surgeries including lymph node dissection and skin graft can cause various complications, and these complications are frequently associated with significant morbidity and discomfort. In this review, we summarize the evidence from previous clinical studies regarding the optimal surgical margin for skin cancer and the methods for diminishing the complications associated with dermatologic surgery.

Abstract

Despite the significant progress made in the past several years in pharmacotherapies for skin cancer, such as BRAF/MEK inhibitors, immune checkpoint inhibitors, and Hedgehog pathway inhibitors, surgical removal of primary skin cancer is still the first choice of treatment unless distant metastases are evident. In cases of lymph node metastases with clinically palpable lymphadenopathy, lymph node dissection (LND) is typically performed for most skin cancers. In the surgical treatment of primary skin tumors, the surgical margin is critical not only for reducing the possibility of tumor recurrence but also for minimizing the cosmetic and functional complications associated with wide local excision. In contrast, dermatologic surgery can cause various complications. Although skin graft is frequently used for reconstruction of the surgical defect, extensive graft necrosis may develop if optimal stabilization of the graft is not obtained. LND also sometimes causes complications such as intraoperative or postoperative bleeding and postoperative lymphoceles. Moreover, as in other types of surgery, surgical site infection, intraoperative anxiety, and intraoperative and postoperative pain may also develop. These complications are frequently associated with significant morbidity and discomfort. In this review, we summarize the evidence from previous clinical studies regarding the optimal surgical margin for skin cancer and the methods for diminishing the complications associated with dermatologic surgery.

Surgical Outcomes of Primary Dermatofibrosarcoma Protuberans: A Retrospective, Multicenter Study

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive tumor with a low rate of metastatic disease. Previous series have shown a superiority of Mohs micrographic surgery (MMS) compared with wide local excision (WLE). Likewise, there is paucity of data examining the long-term follow-up of patients.

OBJECTIVE

The purpose of the current study was to examine the outcome of surgical treatment of primary DFSP of the trunk and extremities.

METHODS

We reviewed 236 patients (115 females, 121 males, mean age 41 ± 15 years) undergoing MMS (n = 81, 34%) or WLE (n = 155, 66%) to treat a primary DFSP. Mean tumor size and follow-up was 4 ± 2 cm and 7 years, respectively. Final margins were negative in 230 (97%) patients.

RESULTS

There was no difference (p > 0.05) in patient age, sex, tumor size, negative margin excision, or history of a previous inadvertent excision between patients who underwent WLE and those undergoing MMS. There were two cases of local recurrence and two cases of metastasis, with no difference in the 5-year local recurrence-free survival (98% vs. 99%, p = 0.69) or metastatic-free survival (98% vs. 100%, p= 0.27) between WLE and MMS.

CONCLUSION

There was no difference in oncologic outcome comparing MMS with WLE for DFSP outside the head and neck. The goal of treatment for DFSP is to achieve a negative margin, regardless of surgical treatment modalities. A 'less is more' approach to follow-up can likely be taken for patients with completely resected DFSP in easy-to-examine anatomical areas. In these patients, no formal follow-up should be required.

Risk factors for the development of local recurrence in extremity soft-tissue sarcoma

INTRODUCTION

Local recurrence (LR) is one of the main pitfalls in surgery for extremities soft tissue sarcoma (eSTS). Achieving clear histopathological margins is the most important factor to reduce the risk of LR, but the ability to do so depends on not only surgical technique but also the interplay between tumor biology, anatomical location and surgical approach. The balance between postoperative morbidity and oncological benefits in reducing the risk of LR needs to be considered.

AREAS COVERED

This review will cover which etiological factors for the development of eSTS lead to an increased risk of LR and discuss histological subtypes that have a high risk of LR and which surgical and neoadjuvant therapeutic strategies can minimize the risk of LR.

EXPERT OPINION

The traditional view that surgical radicality always results in low rates of LR, while marginality alone always leads to high rates of relapse, is outdated. In the modern era of surgical oncology, limb salvage and high-level function after resectional surgery are the key surgical goals. The best results are achieved by combining effective neoadjuvant treatments with planned bespoke oncological operations that consider the biological and anatomical factors of each individual sarcoma.

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.