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.

Incidence and cost of dermatofibrosarcoma protuberans in mainland urban China: a nationwide retrospective study 2014-2016.

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma. Limited population-based epidemiological studies on DFSP have been conducted. OBJECTIVES: We aimed to estimate the incidence and disease burden of DFSP in China. MATERIALS & METHODS: We conducted a cross-sectional study using data from the national databases of the Urban Basic Medical Insurance scheme. Cases were identified by ICD code and Chinese language diagnostic terms. National incidence from 2014 to 2016 was estimated by gender and age, and associated medical costs were calculated. RESULTS: A total of 175 patients were confirmed with DFSP from 2014 to 2016. Crude incidence varied from 0.353 per 100,000 (95% CI: 0.203-0.503) in 2014 to 0.367 per 100,000 (95% CI: 0.279-0.455) in 2016. Incidence was higher in males than in females. The first incidence peak was observed between the ages of 20 and 39 years and the highest incidence rates were in those aged over 60 years. Average medical costs of DFSP were higher than the per capita disposable income of residents. CONCLUSION: Incidence of DFSP in mainland urban China is lower than in most developed countries and has remained relatively stable from 2014 to 2016. Further research is expected to clarify the potential pathophysiological mechanisms of DFSP.

Retrospective Analysis of a Modern Cohort of Dermatofibrosarcoma Protuberans From 2000 to 2018.

BACKGROUND: There is limited data on how demographics, tumor characteristics, and treatment methods affect overall survival in patients with dermatofibrosarcoma protuberans (DFSP). OBJECTIVE: To summarize characteristics of patients with DFSP, assess prognostic factors, and evaluate the impact of treatment modality on their overall survival. METHODS: We investigated DFSP using data for 4451 patients with histologically confirmed cases of DFSP diagnosed between 2000 and 2018 from the 18 US regional registries of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. RESULTS: Older age (P < .001) and large tumor size (P = .006) were significantly associated with worse overall survival in controlled analysis. Older age (P < .050), males (P < .001), non-white race (P < .001), and lower median household income (P < .010) were more likely to present with larger tumor size. Different treatments were associated with patient characteristics. Older age (P < .001), non-white race (P < .032), larger tumor size (P < .001), and head/neck location (P < .001) were associated with patients receiving surgery and radiation instead of surgery only. Additionally, men (P < .021), non-whites (P < .001), lower median household income (P < .001), and larger tumor size (P = .003) were less likely to have Mohs micrographic surgery performed over excision. CONCLUSIONS: Age at presentation and tumor size appeared to be notable prognostic factors. Although treatment modality did not significantly influence patient survival, certain patient characteristics are associated with different treatment modalities.

Rare Cutaneous Malignancies in Skin of Color.

BACKGROUND: There is a scarcity of information regarding the clinical characteristics of rare cutaneous malignancies in skin of color that has yet to be comprehensively explored. OBJECTIVE: To review and compile the racial differences in epidemiology, clinical presentation, histology, treatments, and outcomes of 3 rare skin cancers: dermatofibrosarcoma protuberans (DFSP), Merkel cell carcinoma (MCC), and sebaceous carcinoma (SC). METHODS: Several searches with keywords denoting specific skin cancer type and race were conducted on PubMed to complete this narrative review. RESULTS: We analyzed 50 sources that were relevant to the initial objective. CONCLUSION: The literature demonstrates that there are nuances in DFSP, MCC, and SC unique to African Americans, Asians/Pacific Islanders, and Hispanics that may differ significantly from Caucasian counterparts. African Americans consistently suffer from the worst clinical outcomes in all 3 rare cutaneous malignancies reviewed. Greater physician awareness and knowledge of the discussed racial differences is the preliminary step to address these disparities.

Prevalence of dermatofibrosarcoma protuberans in Saudi Arabia over 24 years.: A retrospective single-institution study.

OBJECTIVES: To conduct a descriptive clinicopathological and demographic analysis of dermatofibrosarcoma protuberans among Saudi patients attending a tertiary care center in the eastern province of Saudi Arabia. METHODS: This retrospective, single-center study reviewed the medical records and pathology reports of Saudi patients attending a tertiary center (Johns Hopkins Aramco Health Care) in Dhahran, Saudi Arabia from 1995 to 2019 to identify all cases of dermatofibrosarcoma protuberans. Demographic and phenotypic data were also analyzed. RESULTS: Thirty-five Saudi patients were identified as having dermatofibrosarcoma protuberans. Females constituted 68.6% of patients. The trunk was the most common site of involvement (54.3%), followed by the lower extremities (34.3%), upper extremities (8.6%), and head and neck (2.9%). The mean tumor size was 2.9 cm (standard deviation: ±2.0). There was only one case of distant metastasis of fibrosarcomatous dermatofibrosarcoma protuberans. CONCLUSIONS: Dermatofibrosarcoma protuberans was not frequently encountered in Saudi patients in a tertiary center that treats approximately 187,668 patients. Dermatofibrosarcoma protuberans disease patterns and demographic data were similar to those reported worldwide. Further studies are required to characterize dermatofibrosarcoma protuberans in the Saudi population.

Clinical Outcome of Dermatofibrosarcoma Protuberance. Report From the Bone and Soft Tissue Tumor (BSTT) Registry in Japan.

BACKGROUND: Owing to its rarity, dermatofibrosarcoma protuberance (DFSP) is often inappropriately excised. After unplanned excision (UE), additional excision is commonly performed. We aimed to elucidate the effect of additional excision after UE. PATIENTS AND METHODS: We examined 306 patients with primary DFSP. We analyzed surgical outcomes in 291 patients who received planned excision (PE) or additional excision after UE. RESULTS: Of 306 patients, 194 received PE and the remaining 112 received UE. Of 112 patients, 97 received additional excision after UE. Additional surgery due to complications was more frequent in patients with UE than in those with PE. The 5-year local recurrence-free rate in patients without additional excision after UE was significantly worse than that in those with additional excision after UE. CONCLUSION: If UE is performed, we recommend additional excision for preventing local recurrence; however, the surgical wound should be carefully observed.

Non-human-papillomavirus-related malignancies of the vulva: A clinicopathological study.

BACKGROUND: Malignant tumor of the vulva is the fourth gynecological malignancy in frequency. Close to 70% of all vulvar malignancies are related to high-risk human papillomavirus (HPV) infection. METHODS: A search for non-HPV-related malignant tumors of the vulva was performed in the last 20 years (2000-2020) in the pathology database of a single tertiary institution. We aim to estimate the prevalence of non-HPV-related malignancies in our population, describe clinicopathological features of these tumors and investigate the expression of some potential therapeutic targets. RESULTS: A total of 71 patients were recovered; 26 patients (36%) had the diagnosis of extramammary Paget disease, 17 patients (24%) had basal cell carcinomas, 17 patients (24%) had primary melanomas, 10 patients (14%) had metastatic disease to the vulva and one patient (1%) had a primary dermatofibrosarcoma protuberans. Fifty-four percent of patients with extramammary Paget disease had a secondary malignancy and 12.5% had invasive disease. Programmed death-ligand 1 (PDL-1) was positive in seven out of nine primary melanomas and Her2/neu was overexpressed in six out of seven extramammary Paget disease. CONCLUSION: Non-HPV-related malignancies are important differential diagnoses in patient with vulvar lesions. Additional research is necessary to further understand these complex malignancies and potential new therapeutic targets.

Darier and Ferrand's dermatofibrosarcoma: A carcinologic and cosmetologic challenge in a low-income country.

INTRODUCTION: Dermatofibrosarcoma (DFS) is a common dermic sarcoma. It is a local malignant tumor occurring in young adults. The recurrence potential justifies an R0-type surgery with a three centimeters margin. We report our experience of the management of locally advanced DFS by resection and reconstructive surgery. METHODS: It is an ongoing descriptive study spanned from June 2005 to December 2018. We included all DFS cases treated by curative resection and reconstruction. A total of eight cases of DFS among 108 soft tissue sarcomas were studied. All patients were males. The mean age was 41.8 years [32-60]. Carcinologic results, cosmetic results, and outcomes were analyzed. RESULTS: R0-type resection was performed in six cases. In two cases, the resection was R1-type and resulted in amputation. In four cases, it was an iterative surgery. Average desease duration was 4 years [1-8]. Reconstructive surgery was needed for wound closure in six cases. Wounds healed in 28 days [18-90]. Outcomes showed hyperchromic keloid scars (N=2) at the trunk localization. CONCLUSION: DFS is a common cancer with a good outcome if managed earliest. Delayed diagnoses and inadequate first-time surgery led to tumor extension and recurrences. Locally advanced tumors management needs extensive resections and reconstructive surgery. In addition to surgery, Imatinib and radiotherapy improve outcomes, but are not available in our context.

Perspectives of Patients With Dermatofibrosarcoma Protuberans on Diagnostic Delays, Surgical Outcomes, and Nonprotuberance.

Importance: Dermatofibrosarcoma protuberans (DFSP) may have a deceptively benign clinical appearance, including a nonprotuberant presentation. Patients with DFSP often perceive misdiagnoses and delays in receiving a diagnosis. Use of existing, patient-designed Facebook patient support groups (FBSGs) to recruit large numbers of patients with rare diseases may be an effective novel research method. Objectives: To collaborate with patients with rare disease through social media and answer questions important to both patients and the medical field, including sources of diagnostic delay, risk of recurrence, and flat presentation of DFSP. Design, Setting, and Participants: A multiple-choice survey created by a team of medical practitioners and patients with DFSP was administered to 214 patients with DFSP or family members from international DFSP FBSGs and a nonprofit foundation patient database via Lime Survey from October 30 to November 20, 2015. The survey asked questions designed to determine risk of recurrence and metastasis, surgical outcomes, sources of diagnostic delay, symptoms of recurrence, number of recurrences, scar size, and number of clinicians seen before biopsy. Statistical analysis was performed from January 1, 2016, to April 1, 2019. Main Outcomes and Measures: The study goal was to collect at least 200 survey responses. Results: Of 214 survey respondents (169 females and 45 males; mean [SD] age, 40.7 [12.1] years; range, <1 to 72 years), 199 were patients with DFSP and 15 were family members. Delays occurred between the patient noticing the DFSP lesion and receiving a diagnosis of DFSP (median, 4 years; range, <1 to 42 years). Most patients (112 [52.3%]) believed that they received a misdiagnosis at some point: by dermatologists (35 of 107 [32.7%]), primary care clinicians (80 of 107 [74.8%]), or another type of physician (27 of 107 [25.2%]). The most frequent prebiopsy clinical suspicion included cyst (101 [47.2%]), lipoma (30 [14.0%]), and scar (17 [7.9%]). Many patients first noticed their DFSP as a flat plaque (87 of 194 [44.8%]). Of these lesions, 73.6% (64 of 87) became protuberant eventually. Surgical treatments included Mohs micrographic surgery (56 of 194 [28.9%]), wide local excision (122 of 194 [62.9%]), and conservative excision (16 of 194 [8.2%]). The reported rate of recurrence was 5.4% (3 of 56) for Mohs micrographic surgery, 7.4% (9 of 122) for wide local excision, and 37.5% (6 of 16) for conservative excision. The higher rate of recurrence for conservative excision was significant (P = .001); there was no significant difference in the rate of recurrence between Mohs micrographic surgery and wide local excision (P = .76). Conclusions and Relevance: This study reports what appears to be disease-relevant statistics from the largest survey of patients with DFSP to date. Because of the dissonance between the name of the neoplasm and its clinical presentation, the alternative term dermatofibrosarcoma, often protuberant is proposed. This study suggests that FBSGs are useful tools in medical research, providing rapid access to large numbers of patients with rare diseases and enabling synergistic collaborations between patients and medical researchers.

Dermatofibrosarcoma Protuberans Re-excision and Recurrence Rates in the Netherlands Between 1989 and 2016.

Dermatofibrosarcoma protuberans is a rare soft tissue tumour with a very low (p < 0.5%) rate of metastasis. Rates of re-excision and recurrence were determined using data from the Netherlands Cancer Registry between 1989 and 2016. Of the 1,890 instances of dermatofibrosarcoma protuberans included, 87% were treated with excision, 4% with Mohs micrographic surgery, and 9% otherwise or unknown. Linked pathology data were retrieved for 1,677 patients. Half of all excisions (847/1,644) were incomplete and 29% (192/622) of all re-excisions were incomplete. The cumulative incidence of a recurrence was 7% (95% confidence interval (95% CI) 6-8) during a median follow-up of 11 years (interquartile range (IQR) 6-17). After Mohs micrographic surgery (n = 34), there were no recurrences during a median follow-up of 4 years (IQR 3-6). Due to the high rate of incomplete excisions and recurrences after excision, this study supports the European guideline, which recommends treating dermatofibrosarcoma protuberans with Mohs micrographic surgery in order to decrease the rate of recurrence.

Outcome after surgical treatment of dermatofibrosarcoma protuberans: Is clinical follow-up always indicated?

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare soft tissue sarcoma for which clinical examination up to 10 years is recommended. The objective of this study was to identify prognostic factors for recurrences and metastases that can be used to evaluate the validity of follow-up schedules after treatment for DFSP. METHODS: Patients with DFSP who received treatment between 1991 and 2016 at 3 tertiary centers were included. Cox regression analyses were conducted to identify variables associated with the primary endpoints. RESULTS: In total 357 patients were included, with a median age of 38 years (age range, 2-87 years) and a median follow-up of 60 months (interquartile range, 24-115 months). Eighty-one patients developed recurrent disease (22.7%), and the median time to recurrence was 55.5 months (interquartile range, 20-90 months). Of these, 50 tumors (61.7%) were identified by patient self-examination, whereas 3 recurrences (3.7%) were identified at clinical surveillance. For the remaining 28 tumors, no information was available on how the recurrences were identified (34.6%). Fibrosarcomatous change (hazard ratio, 21.865; P < .001), and positive resection margins (hazard ratio, 14.645; P < .001), were independent prognostic factors for recurrence. Metastases occurred in 4 patients (1.1%). All tumors were identified by imaging after patients presented with symptomatic metastases. Fibrosarcomatous change (P < .001) and tumor size >5 cm (P = .014) were associated with the development of metastases. CONCLUSIONS: Disease recurrence after resection of DFSP remains a significant issue, whereas metastases are uncommon. The majority of recurrences are identified by patient self-examination. Consideration should be given to individualized follow-up schedules based on risk factors for recurrences and metastases.

Histopathological pattern of skin cancer in Western region of Saudi Arabia. An 11 years experience.

OBJECTIVES: To determine the histopathological pattern of skin cancer in Madinah region of Kingdom of Saudi Arabia (KSA). Methods: This is a retrospective study including all cases with a histological diagnosis of skin cancer diagnosed at the Department of Pathology, King Fahad Hospital, Madinah, Saudi Arabia, between January 2006 and December 2017. Data included  age, gender, site and histology of the tumor were collected from histopathological reports and analyzed using Statistical Package for the Social Sciences  (SPSS) Version 21. Results: Among the 202 cancer cases studied in our series, there were 124 (61.4%) cases of basal cell carcinoma (BCC), 33 (16.3%) cases of squamous cell carcinoma (SCC), 14 (6.8%) cases of mycosis fungoides (MF), 12 (5.8%) cases of dermatofibrosarcoma protuberans (DFSP) and 7 (3.7%) cases of malignant melanomas (MM). The male to female ratio for all cases was 2.2:1. The ages ranged from 5 to 100 years with a mean age of 60.1±15 years. The peak age distribution was in the 60-69 year group. The most common site involved in BCC and SCC was the head and neck (92.7% and 66.7%) respectively). Acral distribution of MM was seen in 57.1% of the cases. Conclusion: Our data based on the histopathology history in the Madinah region match that in the world literature and Saudi national studies.

Hormone receptors analysis in Chinese patients with dermatofibrosarcoma protuberans.

BACKGROUND AND OBJECTIVES: Dermatofibrosarcoma protuberans (DFSP) is a relatively rare skin tumor. Clinical observations indicated that DFSP has a more aggressive behavior during pregnancy, which suggest there might be a hormonal influence on this tumor. We evaluated the expression of estrogen receptor (ER) and progesterone receptor (PR) in DFSP patients. METHODS: In our present case series, patients with histopathological-confirmed DFSP at a single institution were identified. The clinical, pathological, and immunohistochemical data were gathered for each patient. Expression of ER and PR were determined on formalin-fixed, paraffin-embedded tissue sections using immunohistochemistry. Some objective clinical and pathological indicators were then selected to compare between ER and PR status. RESULTS: Immunoreactivity revealed none of these tumors stained positively for ER, while eight tumors (28.6%) stained positively for PR. There was a statistically significant difference in the distribution of tumor location between the PR-positive/negative groups. CONCLUSIONS: This finding suggests that progesterone may have potential effects in growth of DFSPs. Further studies are needed to fully address this question.

Do cancer registries play a role in determining the incidence of non-melanoma skin cancers?

Non-melanoma skin cancers have the highest incidence of all malignancies worldwide. However, cancer registries rarely include data on non-melanoma skin cancers because they tend to be under-reported. To determine incidence rates and changes over time for non-melanoma skin cancers in a mid-sized Brazilian population. We calculated age-standardized rates, adjusted to the world population using the direct method, from 1996-2012 in the Aracaju Cancer Registry and then calculated incidence trends using the Joinpoint Regression Program. We analysed 11,476 cases (5,695 men and 5,781 women) of non-melanoma skin cancer collected during the study period. The histological subtypes in men were 84.5% basal cell carcinoma, 14.5% squamous cell carcinoma, and 1% other histological subtypes, whereas the corresponding percentages in women were 89.1%, 10%, and 0.9%, respectively. Average incidence age-standardized rates were 228.6 (95% CI: 221.6; 235.6) per 100,000 men and 145.4 (95% CI: 141.0; 149.9) per 100,000 women. The incidence mostly increased in the first years for the series and then stabilized. The under-reporting of non-melanoma skin cancers, due to removal of lesions without histopathological confirmation, decisions to keep skin lesions under observation instead of excising them, and deferring medical examination, is a potential pitfall of this study. Age-standardized incidence of non-melanoma skin cancer was high during the study period, but tended to stabilise in the latter years of the study.

Dermatofibrosarcoma protuberans: clinicopathologic presentation in Nigerians.

INTRODUCTION: Dermatofibrosarcoma protuberance (DFSP) is in general a rare low grade malignant sarcoma and possesses a tendency for local recurrence. It has a site predilection for the trunk. Occurrence in the facial area is extremely rare. Ample knowledge of its clinical, histological and biologic characteristics is vital for accurate and prompt recognition. METHODS: Over 13 years, clinicohistologic information of cases was retrieved. Histological and immunohistochemical re-evaluation were performed to re-confirm diagnosis. Data collected and analyzed with SPSS Statistics version 20 were presented as frequency tables, charts and proportions as appropriate. RESULTS: Of 191 soft tissue sarcomas, a total of 28 cases were diagnosed as DFSP (14.7%). Facial types occurred in 3 cases (1.6%). Tumour had age and site predilections for the 4th decade and trunk respectively. There was an equal gender distribution among cases. Most common clinical presentation was in form of painless protruding nodular mass. General histologic presentation revealed cellular lesions composed of spindle to oval neoplastic cells arranged in a storiform pattern. Mitotic figures were rare. All cases showed positive expressions to CD34. CONCLUSION: Facial DFSP is rare among Nigerians. Its clinical appearance may mimic other common benign lesions of the head and neck region often resulting in misdiagnoses. A comprehensive knowledge of its clinical and histologic presentations and biologic behavior, combined with its identification with the aid of advanced histologic and radiographic techniques results in prompt confirmatory diagnosis. Appropriate treatment should include adequate surgical excision techniques combined with adjuvant radiotherapy or chemotherapy.

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.

The management of soft tissue tumours of the abdominal wall.

BACKGROUND: Soft tissue tumours of the abdominal wall account for approximately 10% of all soft tissue tumours. Tumours at this site comprise a heterogeneous group of pathologies with distinct clinical behaviours and responses to treatment. The management of these tumours has largely been extrapolated from studies of soft tissue tumours at other sites. This review aims to summarise the existing data relating to abdominal wall tumours and suggest principles for managing soft tissue tumours at this site. METHODS: Relevant articles were retrieved from a comprehensive literature search using the PubMed database. Key words included abdominal wall, soft tissue tumours, surgery, radiotherapy and chemotherapy. No restrictions on publication date were used. RESULTS: The most common pathologies presenting in the abdominal wall are desmoid tumours, soft-tissue sarcoma and dermatofibrosarcoma protuberans (DFSP). Desmoid tumours should be managed with an initial period of observation, with surgery reserved for progressive lesions. Surgery should be the primary treatment for soft-tissue sarcomas and DFSP, with radiotherapy reserved for large-high grade tumours and preferentially given pre-operatively. CONCLUSIONS: Abdominal wall tumours are rare and should be managed in centres with experience in the management of soft tissue tumours. Management should be tailored to the biological behaviour of specific pathologies.