Dermatofibrosarcoma protuberans: Wide local excision vs. Mohs micrographic surgery

Mohs micrographic surgery for cutaneous malignancies: A focus review of its indications in pediatric age groups

Mohs micrographic surgery (MMS) is a highly specialized technique that has been successful in the treatment of a variety of skin tumors. The technique can be performed as an outpatient procedure and encompasses surgical excision and intraoperative assessment of tumor margins in one setting by the same physician. The process ensures precise margin control with maximal preservation of healthy tissues. Mohs micrographic surgery has been practiced worldwide, including in the United States, Europe (United Kingdom, Germany, Spain, Netherlands, Switzerland), and Australia. Although it is commonly performed in adults with greater success, it has been discussed less frequently in children. In this article, we describe several cutaneous tumors in children and the role of Mohs micrographic surgery in their management. A PubMed search was conducted to review the most common cutaneous tumors in children treated using Mohs micrographic surgery. In this review, we discuss indications for Mohs micrographic surgery and pertinent studies examining success rates in children. Mohs micrographic surgery has been used to treat several tumors in children and offers the advantage of high cure rates and tissue conservation. This report emphasizes the benefits of Mohs micrographic surgery in children and highlights several cutaneous tumors for which it has been used to treat successfully.

Dermatofibrosarcoma protuberans: A clinical analysis

Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous tumor with a high incidence of misdiagnosis. DFSP has a high rate of recurrence but a low rate of metastasis. In the present study, retrospective analyses were performed on the clinical features, differential diagnosis and treatment of patients with DFSP to improve our understanding of the disease and allow more effective treatment measures to be implemented. The present study investigated the clinicopathological features of 70 pathologically confirmed cases of DFSP at the First Affiliated Hospital of Zhengzhou University (Zhengzhou, China) between March 2012 and 2017. The primary endpoint was recurrence rate. Three cases were analyzed in detail. The results revealed that 7 of the 41 primary patients (follow-up at 2.7 years) had recurrence (17.1%), compared with 11 (37.9%) of the 29 recurrent patients (follow-up at 2.0 years, P=0.049). Of the 59 patients with DFSP (follow-up at 2.6 years), 12 had recurrence (20.3%) compared with 6 (54.6%) of the 11 patients with fibrosarcomatous DFSP (FS-DFSP; follow-up at 2.1 years, P=0.045). DFSP requires diagnosis by pathological examination, and surgical resection is the main treatment. DFSP demonstrated a high recurrence rate, with the degree of malignancy increasing following multiple recurrences. FS-DFSP had a higher risk of local recurrence and distant metastasis, and a higher degree of malignancy than classic DFSP. These data may be useful to guide clinicians to improve decisions in the treatment of patients with DFSP.

Dermatofibrosarcoma Protuberans: Retrospective Single Center Analysis Over 16 Years

Dermatofibrosarcoma protuberans (DFSP) is rare mesenchymal neoplasia with a high risk of local recurrence but a low risk of metastatic spread. Tumor cells express CD34 and show a characteristic translocation t(17;22)(q22;q13). We analysed the documented cases at the Department of Dermatology and Allergology between 08/2001 and 08/2017. The diagnosis had been confirmed by histology and immunohistology in all cases. We identified four adults and a pediatric patient with DFSP. All patients were treated by wide surgical excision and controlled by three-dimensional histologic margin control. We observed no recurrence and no metastatic spread. We discuss prognostic factors and emerging treatments.

Dermatofibrosarcoma Protuberans

OPINION STATEMENT

Dermatofibrosarcoma protuberans (DFSP) is a slow growing tumor with a very low metastatic potential but with significant subclinical extension and great capacity for local destruction. Thus, the first surgeon approached with such challenging tumor must attempt to cure the patient with a method that spares healthy tissue and ensures an optimal oncological, functional, and esthetic result. The treatment of DFSP often requires a multidisciplinary approach. Depending on location, dermatologic surgeons, surgical oncologists, head and neck surgeons, neurosurgeons, plastic surgeons, and occasionally medical oncologists may be involved with the management. Mohs micrographic surgery (MMS) is the preferred method when available. In our institution, most of the DFSP cases are often advanced cases; thus, dermatologic surgeons obtain clear margins peripherally and other surgical specialties assist with resection of the fascia and any critical deeper structures. When MMS is not available, wide local excision (at least 2- to 3-cm margins of resection) with exhaustive pathologic assessment of margin status is recommended, and it is best to confirm tumor extirpation prior to any reconstruction. Subclinical extension of the tumor could be related to the size; how long it has been growing or histological markers that are unknown right now. No clinical trials comparing MMS vs WLE are available, and further research should be focused on these subjects as well as the use of imatinib and other targeted therapies for recurrent and metastatic tumors and for neoadjuvant treatment.

Wide local excision vs. Mohs Tübingen technique in the treatment of dermatofibrosarcoma protuberans: a two-centre retrospective study and literature review

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade mesenchymal skin tumour, characterized by slow infiltrative growth and common local recurrence, with infrequent distant metastases.

OBJECTIVE

The aim of this study is to better clarify clinicopathological characteristics of this tumour and to evaluate the cure rates of Mohs Tübingen technique (MTT) and wide local excision (WLE). Eventually, we perform a literature review to compare our experience with published data.

METHODS

A retrospective review was conducted on 135 patients diagnosed, treated and followed up between 1997 and 2014 at two different institutions. Sixty-two patients underwent to WLE and 73 to MTT. The primary end-points were the following: percentage of recurrences, time to progression and recurrence annual risk rate. Then, the PubMed database was searched for DFSP case series treated with standard surgical resection (SSR), WLE, Mohs' micrographic surgery (MMS) and MTT. The annual risk rate of recurrence calculated and reported for the four separate procedures was pooled to compare them.

RESULTS

Five of the 62 patients with WLE (8.1%) experienced recurrences after a mean follow-up of 4.7 years; the percentage of recurred patients 9 years after MTT was 5.5%, and the annual recurrence risk rate of 0.6%. Pooling these data with those from literature, the recurrence rate varies from 26% to 60% for SSR, from 0% and 41% for WLE, from 0% and 8.3% for MMS and from 0% to 5.5% for MTT. The lowest annual recurrence risk rate was found for MTT.

CONCLUSION

Significantly lower recurrence rates were recorded in patients treated with classic or Tübingen Mohs' technique. To the best of our knowledge, our case series is the widest treated with MTT ever described in the literature; these data may be useful to guide clinicians in the choice of the gold standard treatment for Dermatofibrosarcoma protuberans.

Unnecessary Cost of Post-Mohs Permanent Pathology

BACKGROUND

By providing tumor-free margins, Mohs micrographic surgery (MMS) results in high cure rates in the treatment of nonmelanoma skin cancers (NMSCs). However, when closure of the post-MMS defect is coordinated with reconstructive surgery, redundant tissue is sometimes submitted for permanent section evaluation.

OBJECTIVE

The purpose of our study was to investigate the frequency and effect of this practice.

MATERIALS AND METHODS

Patients (12 years and older) with NMSCs cleared by MMS with coordinated closures from 2014 to 2016 were identified. Cost analysis was performed using the 2016 Current Procedural Terminology codes and averaged nation-wide Medicare reimbursement rates.

RESULTS

During the study period, 408 cases were coordinated with reconstructive surgeons post-MMS. Of these, 125 had specimens were submitted for permanent section with none showing residual malignancy. There were no significant differences between the cases sent for permanent section and the remaining coordinated MMS cases, with respect to patient age, to basal cell and squamous cell carcinoma histology, or to defect size (p > .05). The marginal cost of sending specimens for permanent section was $121 per case.

CONCLUSION

Sending post-MMS redundant tissue for permanent sections may be of limited utility and should not be performed routinely. Additional work is warranted to determine when this practice should be used in conjunction with MMS.

A Comparison of Mohs Micrographic Surgery and Wide Local Excision for Treatment of Dermatofibrosarcoma Protuberans With Long-Term Follow-up: The Mayo Clinic Experience

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a soft tissue tumor with slow infiltrative growth and local recurrence if inadequately excised.

OBJECTIVE

To compare long-term outcomes after Mohs micrographic surgery (MMS) and wide local excision (WLE).

MATERIALS AND METHODS

Records of patients with DFSP surgically treated with WLE or MMS from January 1955 through March 2012 were retrospectively reviewed.

RESULTS

Mean follow-up for patients treated with MMS (n = 67) and WLE (n = 91) was 4.8 and 5.7 years, respectively. Twenty-eight patients (30.8%) with WLE had recurrence (mean, 4.4 years), whereas only 2 (3.0%) with MMS had recurrence (1.0 and 2.6 years). Recurrence-free survival rates at 1, 5, 10, and 15 years were significantly higher with MMS (p < .001). Mean preoperative lesion sizes were similar (5-6 cm) between the 2 groups, whereas mean (standard deviation) postoperative defect sizes were 10.7 (4.3) cm and 8.8 (5.5) cm for WLE and MMS, respectively (p = .004). Primary closure was used for 73% of MMS cases, whereas WLE more commonly used flaps, grafts, or other closures (52%). Two Mohs layers typically were required for margin control.

CONCLUSION

Surgical excision with meticulous histologic evaluation of all surgical margins is needed for DFSP treatment to achieve long-term high cure rates and low morbidity.

A single-institutional review of 68 patients with dermatofibrosarcoma protuberans: wide re-excision after inadequate previous surgery results in a high rate of local control

Background

Dermatofibrosarcoma protuberans (DFSP) is a cutaneous soft tissue sarcoma characterized by an indolent but aggressive local growth. Unplanned excisions with positive margins are common, and the prognostic impact of radical re-excisions is still unclear. The aim of the present study was to identify prognostic indicators of recurrence-free survival (RFS) in patients with DFSP through a long-term follow-up. We tried particularly to determine the prognostic impact of surgical margins and re-excisions in patients after earlier inadequate surgery.

Methods

Seventy-five patients with DFSP were treated surgically at our institution between 1999 and 2015. Analyses were restricted to 68 participants with available information on surgical margins. The median follow-up was 5.4 years.

Results

Fifty-four patients (79.4%) had low-grade DFSP and 14 patients (20.6%) intermediate-grade FS-DFSP. The 5-year RFS rates were estimated to be 93.5% (95% CI 81.2–97.9) for low-grade DFSP and 39.7% (95% CI 13.0–65.8) for FS-DFSP (P < 0.0001). Re-excisions were performed in 55 patients (80.9%) following R1 or marginal R0 resections. Negative margins could be attained in a total of 65 patients (95.6%). Negative margin widths >1 cm led to the best local outcome within the R0 subgroup. Significant adverse prognostic features in the multivariate analysis included histologic grade and close margins.

Conclusions

The data from this study underscore the long-term benefit of negative margins. In our analysis, re-excisions were an effective method to achieve a high rate of local control in patients who presented after R1 or marginal R0 resection. To ensure the best outcome, re-excisions should aim at negative margin widths of more than 1 cm in the histologic specimen.

Dermatofibrosarcoma Protuberans: A comprehensive review on the spectrum of clinico-radiological presentations

Dermatofibrosarcoma Protuberans (DFSP) is a rare malignant soft-tissue neoplasm which is often misdiagnosed due to its indolent clinical course and non-specific radiological appearances. An observation case series was conducted with retrospective review of clinical and radiological data of DFSP patients presenting to a major tertiary hospital in Hong Kong for radiological assessment between November 2006 and February 2016. Seven patients with confirmed histological diagnosis of DFSP were included. Tumour sizes at presentation ranged from 1 to 5 cm, most commonly (n = 6) occurred over chest wall and abdominal wall. History of previous local trauma or surgery was identified in the majority of cases (n = 4). There was poor correlation between pre-imaging clinical diagnoses and pathological diagnoses. Local recurrence and tumour de-differentiation with sarcomatous changes occurred in the minority of cases (n = 2). A common radiological 'claw' sign at the lesion/skin interface formed by elongated appendages of the tumour superficially was appreciated in most cases (n = 6). A history of previous local trauma or surgery serves as a possible etiological factor for the development of DFSP. High clinical suspicion for the entity is essential in its detection and differentiation from simple wound complications and local recurrence of other benign lesions. The radiological 'claw' sign at the lesion/skin interface might serve as a tell-tale sign for cutaneous tumour involvement. A comprehensive analysis of imaging findings in conjunction with individual clinical presentations is the key to accurate diagnoses and proper management.

Indication guidelines for Mohs micrographic surgery in skin tumors

Mohs micrographic surgery is a technique used to excise skin tumors based on comprehensive surgical mapping, in which the surgeon removes the tumor, followed by a complete histological evaluation of the tumor's margins. The correlation of the presence of a tumor in histological examinations and its precise location on the surgical map result in a complete removal of the tumor with maximum normal tissue preservation. The present article seeks to provide general practitioners and healthcare specialists with guidelines regarding recommendations for Mohs micrographic surgery to treat skin tumors, based on the most reliable evidence available in medical literature on the subject. This bibliographic review of scientific articles in this line of research was conducted based on data collected from MEDLINE/PubMed. The search strategy used in this study was based on structured questions in the Patient, Intervention, Control, and Outcome (PICO) format. MeSH terms were used as descriptors. The indications of this technique are related to recurrence, histology, size, definition of tumor margins, and location of tumors. These guidelines attempt to establish the indications of Mohs surgery for different types of skin tumors.

Dermatofibrosarcoma Protuberans: Wide Local Excision Versus Mohs Micrographic Surgery

Dermatofibrosarcoma protuberans (DFSP) is a rare dermal soft tissue sarcoma characterized by a typically indolent clinical course. The greatest clinical challenge in management of DFSP is achieving local control. There is vigorous debate in the literature as to the optimal surgical approach to these tumors. The choice between wide local excision and Mohs micrographic surgery for DFSP should be governed by the attainment of three goals: (1) to completely excise the tumor with negative margins, tantamount to cure; (2) to preserve function, optimize cosmesis, and minimize morbidity of resection; and (3) to minimize cost and inconvenience to the patient and the health care system at large.

A Challenging Giant Dermatofibrosarcoma Protuberans on the Face

Dermatofibrosarcoma protuberans (DFSP) is a malignant fibrohistiocytic tumor that appears exclusively on the skin. It is a low-grade malignant soft tissue tumor of subcutaneous tissues that has a propensity for local recurrence but seldom metastasizes. It may rarely occur on the head and neck accounting for less than one percent of total head and neck malignancies. We present a man with a giant DFSP on the face. Oncological, functional, and aesthetic aspects are set forth.

Dermatofibrosarcoma protuberans: from translocation to targeted therapy

Dermatofibrosarcoma protuberans (DFSP), the most common dermal sarcoma, is a low-grade, slow growing fibroblastic malignant neoplasm that most frequently affects middle aged adults and is characterized by a high local recurrence rate and a low propensity for metastasis. Wide surgical resection or Mohs micrographic surgery (MMS) are the preferred approaches for localized disease, while radiation therapy is warranted for inoperable disease or for cases with positive margins where re-excision is not possible. DFSP is generally regarded as refractory to conventional chemotherapy. Treatment options for systemic disease were limited until the discovery of a unique translocation, t(17;22)(q22;q13) (COL1A1;PDGFB) found in a majority of cases. In recent years, imatinib, a PDGFβR, ABL and KIT inhibitor, has revolutionized systemic therapy in DFSP. In this review, we summarize the epidemiological, clinical, histological and genetic characteristics of DFSP and update the readers on its current management.

Wide Local Excision for Dermatofibrosarcoma Protuberans: A Single-Center Series of 90 Patients

Background. Dermatofibrosarcoma protuberans (DFSP), a rare low-grade sarcoma of fibroblast origin, tends to extend in a finger-like fashion beyond macroscopic tumor margins. Therefore, incomplete removal and subsequent recurrence are common. This study aimed to determine the efficacy of wide local excision (WLE) for controlling local recurrence of DFSP. Methods. The medical records of 90 DFSP patients who received WLE at our hospital between June 1992 and January 2015 were retrospectively reviewed. WLE was conducted including a 3 cm (range, 1 to 5 cm) safety margin according to tumor size, location, and recurrence status. Clinical and tumor characteristics and surgical methods were evaluated for risk factor analysis and local recurrence-free survival. Results. DFSP occurred most often in patients in their 30s (30%) and on the trunk (51.1%). Five patients (5.5%) experienced local recurrence during the 43.4-month follow-up period. Recurrence was found at a mean of 10.8 months after WLE. Although no factors were significantly associated with recurrence, recurrences were more frequent in head and neck. Recurrence-free survival was 87% in 6 years and 77% in 7 years. Conclusions. WLE with adequate lateral and deep margins can effectively control local recurrence rate and is a simple and effective method to treat DFSP.

Dermatofibrosarcoma protuberans: a study of clinical, pathologic, genetic, and therapeutic features in Korean patients

PURPOSE

Dermatofibrosarcoma protuberans (DFSP) carries a translocation resulting in the collagen type I alpha 1 (COL1A1)-platelet-derived growth factor beta (PDGFB) fusion gene, which is responsible for PDGFB activation. The purpose of this study is to evaluate the clinicopathological, genetic, and therapeutic features of DFSP in Korean patients.

MATERIALS AND METHODS

Clinicopathological features of 37 patients with DFSP were reviewed. Multiplex reverse transcriptase-polymerase chain reaction (PCR) was carried out in 16 patients using formalin-fixed, paraffin-embedded tissues and specific primers for COL1A1 and PDGFB.

RESULTS

The mean age of 37 patients was 37.4 years old. The most common tumor location was the trunk. All patients were treated primarily with surgery: 34 (91.7%) cases with Mohs micrographic surgery (MMS) and 3 (8.3%) cases with wide local excision. The median follow-up time was 33.7 months. Two patients, one in each treatment group, demonstrated local recurrence during the follow-up period. The COL1A1-PDGFB fusion gene was expressed in 14 (87.5%) cases, demonstrated by reverse transcriptase PCR analysis. No association was found among the different COL1A1-PDGFB fusion transcripts, the various histological subtypes and clinical features.

CONCLUSION

Our results support the effectiveness of MMS in treating DFSP. The COL1A1-PDGFB fusion transcript was observed in 87.5% of patients. Therefore, COL1A1-PDGFB is a useful and accurate tool in diagnosing DFSP in Koreans.

Dermatofibrosarcoma protuberans of penis: Case report and literature review

Dermatofibrosarcoma protuberans (DFSP) is a rare mesenchymal skin tumor with intermediate to low grade malignancy and occasional distant metastasis and high rate of recurrence locally. It mostly involves trunk, extremities, scalp, and neck. This article describes a middle-aged married male with a DFSP lesion involving ventral aspect of glans and distal shaft of penis who underwent local excision and primary closure. The patient was tumor-free at three years of follow-up.

Mohs micrographic surgery for dermatofibrosarcoma protuberans (DFSP): a single-centre series of 76 patients treated by frozen-section Mohs micrographic surgery with a review of the literature

Dermatofibrosarcoma protuberans (DFSP) is a rare low-grade sarcoma that typically presents with local invasion but rarely metastasises. Surgical excision remains the first-line treatment for DFSP. There are no randomised controlled or prospective studies comparing wide local excision (WLE) with Mohs micrographic surgery (MMS), but available evidence from the retrospective studies and case series available has consistently shown higher recurrence rates for standard surgery and WLE than for MMS. Combined recurrence rates of data within the last 20 years for WLE have been reported at 7.3% compared with 1.1% for MMS. Our aim was to review the clinical details and recurrence rates of DFSP cases treated with frozen-section MMS in our centre between 1996 and February 2013. The relevant data were collected from the case notes. It involved 76 patients with nine of these patients lost to follow-up. In the remaining 67 (67/76) cases, the recurrence rate was 1.5% during the mean follow-up period of 50 months (2-132). This is comparable to recurrence rates for the MMS in the literature [20,21]. Our series is the largest series for frozen-section MMS reported to date. Based on these findings and the current literature evidence, we advocate MMS as the treatment of choice for DFSP in all locations.

A systematic review of outcome data for dermatofibrosarcoma protuberans with and without fibrosarcomatous change

BACKGROUND

To our knowledge, no systematic review of dermatofibrosarcoma protuberans (DFSP) outcomes based on the presence or absence of fibrosarcomatous (FS) change has been performed.

OBJECTIVE

We sought to compare available outcome data for DFSP versus DFSP-FS.

METHODS

The literature was searched for DFSP and DFSP-FS reports with outcome data (local recurrence, metastasis, or death from disease). Chi-square tests were calculated to determine whether DFSP and DFSP-FS significantly differed in risk of local recurrence, metastasis, and death from disease.

RESULTS

In all, 24 reports containing 1422 patients with DFSP and 225 with DFSP-FS are summarized. Risk of local recurrence, metastasis, and death from disease in DFSP-FS was significantly higher as compared with DFSP (local recurrence 29.8% vs 13.7%, risk ratio 2.2 [95% confidence interval 1.7-2.9]; metastasis 14.4% vs 1.1%, risk ratio 5.5 [95% confidence interval 4.3-7.0]; and death from disease 14.7% vs 0.8%, risk ratio 6.2 [95% confidence interval 5.0-7.8]). There was no significant difference in DFSP-FS outcomes based on proportion of FS change within tumors.

LIMITATIONS

This study is based on previously reported data from different hospitals with no uniform process for reporting FS change. The impact of confounders (age, immune status, tumor location, treatment) could not be evaluated because of limited data.

CONCLUSION

Based on available retrospective data, risk of metastasis and death is elevated in DFSP-FS as compared with DFSP. Even a low degree of FS involvement portends worse outcomes.

Dermatofibrosarcoma protuberans in a 10-year-old child

BACKGROUND

Dermatofibrosarcoma protuberans is a rare mesenchymal malignancy in childhood and adolescence. The tumor is characterized by dermal spindle cell proliferation with infiltration of subcutaneous tissue, expression of CD34, and a specific fusion of the platelet-derived growth factor beta with the collagen type 1alpha1 gene.

MAIN OBSERVATION

We observed a 10-year-old girl with a medaillon-like, asymptomatic plaque on the chest that was diagnosed as DSFP. The tumor was completely removed by delayed Mohs surgery. Follow-up so far has shown a complete response.

CONCLUSIONS

The prognosis of dermatofibrosarcoma protuberans in children is excellent as long as early diagnosis is followed by complete excision with Mohs surgery as a golden standard.

Dermatofibrosarcoma protuberans in childhood treated with slow Mohs micrographic surgery

Dermatofibrosarcoma protuberans (DFSP) in childhood is a rare tumor with high recurrence rates. Wide local excision can result in disfiguring mutilation, whereas Mohs micrographic surgery (MMS) reduces surgical margins. MMS in children is not performed routinely, as the required infrastructures such as a histopathology lab in close proximity to the operating room is often lacking. We retrospectively reviewed children diagnosed with DFSP treated at our hospital over 2 years. We recorded surgical treatment details, including margins, duration of inpatient stay, outcome, follow-up, and molecular genetic tumor tissue analysis. Four children with a median age of 6.8 years (range 6.0-8.8 years) were identified who had a diagnostic delay of a median of 2.5 years (range 0.5-4.0 years); all underwent complete tumor excision using the slow MMS technique using vacuum-assisted closure systems between repeated excisions and before wound closure. The median maximal safety margins were 1.5 cm (range 1.0-3.0 cm). By using vacuum-assisted closure systems, no dressing changes were needed, pain was limited, and full mobility was maintained in all children. The median total time in the hospital was 11 days (range 10-14 days). No relapses occurred during a median follow-up of 25.8 months (range 11.3-32.6 months). Collagen 1A1/platelet-derived growth factor B (COL1A1/PDGFB) translocation on chromosomes 17 and 22 was detected in all three analyzable specimens. Lesions suspected of being DFSP warrant prompt histologic evaluation; interdisciplinary management is mandatory in particular for children. Micrographic surgery allows smaller surgical margins than wide excision and should be considered as the treatment of choice in children with DFSP. The interim usage of vacuum-assisted closure systems increases patient comfort. Translocations in the COL1A1/PDGFB gene imply susceptibility to targeted treatment modalities for therapy-resistant cases.

Atrophic dermatofibrosarcoma protuberans: report of a case demonstrated by detecting COL1A1-PDGFB rearrangement

Dermatofibrosarcoma protuberans is a locally aggressive mesenchymal neoplasm. It usually presents as an indurated plaque that protrudes above the surface of the skin. Some patients have clinically persistent plaques that might be atrophic. The atrophic variant of dermatofibrosarcoma protuberans may be confused with some common skin diseases with atrophic appearance. We reported a 40-year-old woman who had a 10-year history of an atrophic dermatofibrosarcoma protuberans. Molecular analysis showed a fusion between COL1A1 exon 31 to exon 2 of PDGFB. The lesion was totally excised, with negative margins of the resection demonstrated by CD34 immunostaining. To our knowledge, this is the second case of atrophic dermatofibrosarcoma protuberans confirmed by detection of COL1A1-PDGFB fusion gene. This appears to be the first report of a fusion between COL1A1 exon 31 to exon 2 of PDGFB in atrophic dermatofibrosarcoma protuberans.

Dermatofibrosarcoma: a rare neoplasm of skin

A 25-year-old lady presented with a small pea-sized lesion on left side of her neck, anteriorly. There was no history of any other lesion on her body. She was medically fit otherwise. An excision was planned, after taking consent from her, which was performed under local anaesthesia as a day procedure. Her postoperative recovery was uneventful. Histopathology showed dermatofibrosarcoma protuberance which is an extremely rare skin tumour. She was further investigated for metastasis. Her CT scan of chest, abdomen and pelvis was performed which showed prominent thymus. Other than this finding, no other abnormality was found in CT scan.

Dermatofibrosarcoma protuberans in children: an update on the diagnosis and treatment

Dermatofibrosarcoma protuberans (DFSP) is a fibrohistiocytic tumor of low grade malignant potential. Although rare, pediatric cases pose a particular challenge in diagnosis and management. In children, the clinical appearance may be heterogeneous and a high index of suspicion is necessary to avoid delays in diagnosis which can lead to further morbidity. Histologic examination, often with the use of appropriate immunostains, is necessary for diagnosis. Advances in the understanding of the molecular genetics of DFSP have led to further diagnostic and therapeutic modalities. DFSP is thought to result from a translocation between platelet-derived growth factor beta (PDGFB, 22q13.1) and type 1 collagen (COL1A1, 17q21≈22) leading to a fusion protein (PDGFB) which stimulates the PDGF receptor. Detection of this translocation in tissue via PCR or fluorescence in situ hybridization (FISH) can be helpful in difficult cases. While surgery with wide local excision or Mohs micrographic surgery is the mainstay of treatment, the use of targeted therapy with imatanib mesylate shows promise in large or unresectable tumors. Knowledge of the clinical features, histology, genetics, and treatment options is important for successful management of these tumors.