Positive margins in excised dermatofibrosarcoma protuberans: a study of 58 cases treated with slow-Mohs surgery

Comparing Mohs micrographic surgery and wide local excision in the management of head and neck dermatofibrosarcoma protuberans: a scoping review

Dermatofibrosarcoma protuberans (DFSP) is a rare, locally aggressive cutaneous sarcoma with a propensity for recurrence. Its management, particularly in the head and neck (H&N) region, presents unique challenges. This study aimed to evaluate the effectiveness of Mohs micrographic surgery (MMS) compared to wide local excision (WLE) in treating H&N DFSP and its impact on recurrence rates and tissue preservation. A comprehensive search was conducted in PubMed/MEDLINE, yielding 29 relevant studies. We included studies comparing MMS and WLE in adult patients with H&N DFSP and reporting local recurrence outcomes. Data were analyzed using random effects analysis, with a meta-analysis performed for comparative studies. Analysis of studies demonstrated a lower recurrence for MMS. Comparative analysis of five studies involving 117 patients showed a significantly lower recurrence rate in the MMS group (2%) compared to the WLE group (19%). Margin status varied between studies, with some achieving negative margins at shorter distances. In the management of H&N DFSP, MMS has emerged as a superior surgical technique, consistently associated with reduced recurrence rates and the potential for tissue preservation. The adoption of MMS should be considered for its capacity to achieve negative margins with fewer processing steps, particularly in anatomically complex regions like the H&N.

Preoperative 3D Reconstruction Model in Slow Mohs Surgery for Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a type of skin cancer that is extremely rare. Its standard treatment is either surgical wide-local excision (WLE) or Mohs micrographic surgery (MMS). Which method has the lowest recurrence rate is unknown. Dermatofibrosarcoma protuberans is an uncommon soft tissue sarcoma with a high propensity for recurrence. It has always remained a clinical challenge. More technology is needed to treat the disease. We reviewed our cases and published experience and evaluated whether 3D modeling could precisely define tumor morphological characteristics and assist excision in slow Mohs surgery. There were 18 dermatofibrosarcoma protuberan cases enrolled. They were treated in Shanghai Ninth People's Hospital from 2014 to 2019. All the 18 included patients presented with primary disease and no metastasis. All subjects had undergone thorough imaging examinations including CT and MRI. The 3D tumor reconstruction models were created for their tumors. We precisely estimated tumor boundaries and sizes according to those 3D models. Afterward, patients underwent slow Mohs surgery and surgical repair of tissue defects following tumor resection. The 3D tumor reconstruction models were successfully established. The predicted tumor volumes were measured in all 18 cases. The average volume was 38.5 cm3 (range: 8.4 cm3-183.6 cm3), which allowed for accurately locating the tumor. Tumors were completely removed in one stage of slow MMS surgery. In the second-stage surgery, the defects were repaired by different surgical methods including direct soft tissue closure, skin grafting, local flaps, or free flaps. Most patients experienced no significant complications. This practice indicated that the combination of a 3D reconstruction model and slow Mohs surgery achieves more precise and complete DFSP resection to decrease the recurrence rate.

Determination of Margins for Tumor Clearance in Dermatofibrosarcoma Protuberans: A Single-Center Study of 222 Cases Treated With Modified Mohs Surgery

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is an invasive skin tumor traditionally associated with very high recurrence rates when treated with conventional surgery (CS).

OBJECTIVE

To calculate the minimum margin that would have been required to achieve complete tumor clearance with hypothetical CS. To analyze DFSP characteristics and Mohs micrographic surgery (MMS) effectiveness in treatment of this tumor.

MATERIALS AND METHODS

Minimum margin was calculated by measuring the largest distance from the visible edge of the tumor to the edge of the surgical defect. Tumor variables (age, sex, size, time since onset, and location) were correlated with surgical variables (number of stages and minimum margin).

RESULTS

We studied 222 cases of DFSP treated with MMS. A mean of 1.47 MMS stages and a mean minimum margin of 1.23 cm were required to achieve tumor clearance. Tumors on the head and neck required significantly more stages and a significantly wider margin. Tumor size was positively correlated with time to diagnosis, age, and number of MMS stages.

CONCLUSION

Tumors located on the head and neck have greater subclinical extension. Tumor size was also a predictor of surgical difficulty, but time to diagnosis was not.

Systematic review of Mohs micrographic surgery in children: Identifying challenges and practical considerations for successful application

BACKGROUND

Few data exist to guide the application of Mohs micrographic surgery (MMS) in the pediatric population.

OBJECTIVE

We sought to summarize the clinical characteristics of children undergoing MMS, identify challenges that limit the use of MMS in this population, and examine how these challenges can be overcome.

METHODS

A systematic review of PubMed and EMBASE, from inception of databases to November 2, 2019, identified all cases of pediatric skin lesions treated with MMS.

RESULTS

A total of 111 patients were included. The median patient age was 11 years (range 6 weeks to 17 years). The most commonly treated tumor was dermatofibrosarcoma protuberans (n = 62), followed by basal cell carcinoma (n = 30). The most common location was the head and neck (n = 34), followed by the trunk (n = 28) and the extremities (n = 23). The most commonly cited challenges in the application of MMS in children included patient cooperation, concerns for the safety of prolonged general anesthesia, availability of a MMS service in the pediatric setting, and access to a histopathology laboratory experienced in MMS sectioning.

LIMITATIONS

Many articles did not report specific patient characteristics.

CONCLUSION

Multiple obstacles limit the application of MMS in pediatric patients. This review describes practical methods to circumvent these obstacles to facilitate the appropriate use of MMS in children.

The efficacy of Mohs micrographic surgery over the traditional wide local excision surgery in the cure of dermatofibrosarcoma protuberans

Usually most patients with dermatofibrosarcoma protuberans (DFSP) may present rather late when the tumor is in protuberant phase due to its rarity and indolent onset. It has a high propensity for local recurrence and destructive nature. Management of DFSP requires a biopsychosocial and Multidisplinary approach regardless of the clinical or immunohistochemical variant. Surgery is the Gold standard management of localized disease. DFSP rarely exhibits any lymphatic or hematogenous dissemination. It is because of its high recurrence rate associated with Wide Local Excision (WLE), the introduction of Mohs micrographic surgery (MMS) has really helped in reducing the rates of recurrence of DFSP. Thus, the aim of this meta-analysis and systemic review is to advocate for MMS over WLE for DFSP and other cutaneous malignancies using DFSP as a prototype. The objective of this study were to conduct a meta-analysis on comparative surgical methods used in the cure of DFSP with regards to WLE verses MMS, to evaluate the cure rates with relation to recurrence rates, offer a recommendation on the various treatment modalities based on the location of lesion, and use of adjuvant therapy in different clinical-medical setups. A comprehensive retrospective analysis search in EMBASE, Google Scholar and Medline (PubMed) for studies published from 2008 to 2018 containing the surgical management of DFSP with WLE verses MMS were reviewed. Five studies of moderate-quality evidence (level B) with a pooled patient load of 684 was analyzed and found for recurrence of DFSP after WLE and MMS to be 9.10% and 2.72% respectively after an average follow-up time for both groups of 5.32 years with a female predominance of 1.58. The trunk is the commonest site for the DFSP lesion which was at 52.80% then the upper and lower extremities zones and the head and neck zones at 31.75% and 15.45% respectively. The pooled adjusted odds ratio (OR) analysis indicated that there was a direct relationship with regards the reduced recurrence rate of DFSP in the MMS group compared to the WLE group (OR:0.31;95%; CI :0.17-0.56). Furthermore, there was significant association between the reduced recurrence rate with the MMS in DFSP patients with a statistical P-value of 0.0001 at 95% CI. The expected increased recurrence rate by zones was in WLE head and neck zone at 38.19% then trunk and extremities zone at 13.34%. In the MMS group it was at of 23.4% as compared to 16.0% in the head and neck zone. Mohs Micrographic Surgery (MMS) is more efficacious in the cure rate and recurrence reduction of DFSP and should be advocated for as first line therapy especially in high recurrence prone zones.