Ann Surg Oncol (2020) 27:919–923 https://doi.org/10.1245/s10434-019-08011-5 ORIGINAL ARTICLE – SARCOMA Conservative Re-excision is a Safe and Simple Alternative to Radical Resection in Revision Surgery for Dermatofibrosarcoma Protuberans Hayden Snow, MBBS, FRACS1 , Emma Davies, MBBS, iBSc, MRCS1, Dirk C. Strauss, FRCS1, Myles Smith, MB, BCh, BAO, PhD, FRCSI1, and Andrew J. Hayes, MBBS, BA, PhD, FRCS1 Sarcoma and Melanoma Unit, Academic Surgery, The Royal Marsden Hospital, London, UK ABSTRACT recurrence (LR). CRE results in low rates of surgical Background. Dermatofibrosarcoma protuberans (DFSP) reconstruction, and hence lower morbidity; this is partially is a dermal sarcoma often diagnosed by excision biopsy, offset by the higher rates of inadequate excision requiring and is often incompletely excised, with high recurrence further surgery. However, the lesser rate of inadequate rates. Traditional wide excision involves resection margins excision compared with rates of reconstruction makes CRE of 2–4 cm, often resulting in morbid procedures requiring an attractive option. surgical reconstruction. An alternative is conservative re- excision (CRE), which results in narrower margins and less-frequent reconstruction. The aim of this study is to Dermatofibrosarcoma protuberans (DFSP) is a soft tis- assess the effectiveness of CRE in providing local control. sue sarcoma originating in the dermis that invades into the Patients and Methods. A retrospective review of patients subcutaneous tissues. Classical DFSP, accounting for 90% treated for DFSP at a tertiary sarcoma centre over a 10-year of all DFSP, is considered a low-grade malignant neoplasm period. that has a propensity towards LR following resection but Results. Ninety-eight patients were analysed. Median almost no metastatic potential.1,2 The remaining 10% follow-up was 53 months. Fifty-four patients had micro- undergoes transformation into a high-grade fibrosarcoma- scopically incompletely excised DFSP, and of these, 41 tous variant (FS-DFSP), which carries a higher metastatic underwent CRE of DFSP scar. Seven (17.1%) patients risk (5–15%) and behaves more similarly to other high- required more than one CRE to achieve negative margins. grade sarcomas.1,3,4 The mean width of CRE was 15.4 mm. Fifty-four patients Histologically, DFSP is characterised by circumferential had resection of intact tumours, with 19 (35.2%) requiring spread along fibrous septae into the underlying fat,5 and it surgical reconstruction. One patient (1%) developed local is suggested that this microscopic appearance underpins the recurrence, and one patient (1%) distant recurrence—both high rate of LR observed with narrow excisions, failing to of these patients had high-grade fibrosarcomatous DFSP. remove all of these projections, with rates up to 40%.1 No patient with classical DFSP who had clear margins However, whilst many guidelines and authors therefore sustained recurrence, regardless of whether their surgery recommend ‘‘wide’’ surgical excision margins, there is no was CRE of scar or wide excision of tumour. accepted optimal width. The British Sarcoma Group Conclusions. CRE is a safe and acceptable alternative to guidelines recommend wide excision without specifying a traditional wide excision, with no patients developing local margin, while the National Comprehensive Cancer Net- work (NCCN) guidelines state 2–4 cm.6,7 DFSP is often diagnosed unexpectedly after excision of a presumed benign abnormality. Patients are referred with a Ó Society of Surgical Oncology 2019 post-excision scar, with DFSP incompletely excised First Received: 10 June 2019; microscopically. These patients represent a management Published Online: 29 October 2019 conundrum, with an absence of compelling evidence to H. Snow, MBBS, FRACS guide further resection margins to gain local control. Wide e-mail: [email protected] 920 H. Snow et al. excision of these scars with a margin of 2–4 cm frequently RESULTS requires reconstructive surgery, with higher morbidity and longer hospitalisation. An alternative option is to perform a A total of 107 patients were identified, 3 of whom conservative re-excision (CRE), which involves an ellip- presented with metastatic disease after treatment elsewhere tical excision of the scar and tumour bed, including for fibrosarcomas arising in DFSP and were excluded from resection of the deep fascia. The excision is taken with at the subsequent analysis. A further 6 patients who were least 1 cm margin, but as wide as possible while still referred for management advice after radical surgery and allowing primary closure. reconstruction at other institutions were also excluded, The aim of this study is to review a large series of DFSP leaving 98 patients for analysis. The clinicopathologic treated at a tertiary sarcoma centre, assessing for risk fac- characteristics of the patients are summarised in Table 1. tors for recurrence. Primarily, we aim to assess the Five (5.1%) patients had FS-DFSP, four of whom were effectiveness of CRE in providing local control, as an primary presentations while the other one presented with a alternative to traditional wide excision. recurrent tumour. Median follow-up was 53 months (range 0–144 months). PATIENTS AND METHODS The present study is a retrospective review of all Patients Treated with Tumour Bed Excision patients treated for DFSP at a tertiary-referral sarcoma centre (Royal Marsden Hospital, London, UK) between Of the 98 patients, 44 had undergone an initial excision 2006 and 2016. This study was approved by the institu- biopsy at the referring institution, usually for a presumed tional research committee. Medical records, operative benign abnormality. All of these patients had primary reports and histological reports were reviewed for clini- DFSP; none were recurrent tumours. They presented to the copathological data. Patients with both classical DFSP and sarcoma clinic with a post-excision scar only and had no FS-DFSP were included. Follow-up generally consisted of clinical or radiological evidence of residual disease. Of 6-monthly clinical examination and chest x-ray for these patients, 41 underwent CRE with primary closure, 10 years. Due to referral patterns, some patients were and only 3 underwent wide excision with reconstructive discharged to local hospitals for surveillance. As a result, surgery. One of these patients had been closed with a local for a small number of patients (nine), there was limited flap at the time of their excision biopsy and required follow-up in medical records. These patients were con- resection of the entire flap, with a latissimus dorsi flap tacted by telephone to ascertain any further events related reconstruction; the other two had tumours on the scalp and to DFSP. lower limb, both sites well known for their limited skin In patients presenting with a tumour in situ, surgery laxity and frequent need for reconstructive surgery. The consisted of wide excision of the tumour including the deep median size of the tumours excised prior to referral in this fascia as the deep margin. In patients undergoing re-exci- group was 30 mm (range 3–70 mm). sion of a scar with microscopically involved margins (for On average, the width of excision around the scar was previously incompletely excised DFSP), CRE was per- 15.4 mm (therefore, total excision width of specimen was formed as described above. Reconstructive surgery was 30.8 mm), with no patients undergoing excision of less performed at the discretion of the treating surgeon where it than 10 mm margin. was felt that CRE could not be performed in a safe or Seven patients who had conservative re-excision cosmetically acceptable manner. In the case of involved (17.1%) had inadequate pathological margins and required margins on permanent pathological analysis, further CRE further surgery to attain negative margins (Table 2). The was performed until negative margins were achieved, mean width of these re-excisions was 13.8 mm (range where possible. Radiotherapy or systemic therapy was not 10–20 mm). Five of these patients had negative margins routinely administered but given on a case-by-case basis. achieved with a second conservative re-excision, while one Pathological examination involved routine formalin- patient required three conservative re-excisions. One fixed paraffin-embedded sections coupled with immuno- patient had repeated positive margins with three conser- histochemistry for CD34. Intra-operative frozen sections vative re-excisions, and finally a wide resection with were not performed. Surgical margins were collected from latissimus dorsi reconstruction was performed with nega- operative notes or, where this was not recorded, by tive histological margins. macroscopic margins to tumour or scar as reported on the pathology report. Conservative Re-excision is a Safe and Simple Alternative to Radical Resection in Revision… 921 TABLE 1 Clinicopathologic characteristics Tumour bed excision (n = 44) Macroscopic tumour excision (n = 54) Tumour type, n (%) Primary 44 (100) 33 (61.1) Recurrent 0 (0) 21 (38.9) Fibrosarcomatous change, n (%) 1 (2.3) 4 (7.4) Tumour size (mm), median (range) 30a (3–70) 50 (5–150) Excision width (mm), mean (range) 15.4 (10–35) 24 (20–50) Tumour site, n (%) Head and neck 5 (11.4) 10 (18.5) Trunk 28 (63.6) 25 (46.3) Lower limb above knee 5 (11.4) 10 (18.5) Lower limb below knee 2 (4.5) 4 (7.4) Upper limb above elbow 3 (6.8) 4 (7.4) Upper limb below elbow 1 (2.3) 1 (2.3) Reconstructive surgery, n (%) 3 (6.8) 19 (35.2) Inadequate margins requiring re-excision, n (%) 7 (17.1) 4 (7.4) Local recurrence, n (%) 0 (0) 1 (1.9) aSize of tumour prior to excision biopsy TABLE 2 Number of conservative re-excisions required margins, with a mean excision margin of 18.8 mm (range 15–20 mm). All of these patients were then treated with Number of re-excisions Number of patients, n (%) conservative re-excision with negative margins found on 1 34 (82.9) the subsequent excision.