Increase of atypical fibroxanthoma and pleomorphic dermal sarcoma: a retrospective analysis of four German skin cancer centers

• Published in: Journal der Deutschen Dermatologischen Gesellschaft 2022-12, Vol.20 (12), p.1581-1588
• Main Authors: Kuntz, Thomas, Siebdrath, Julian, Hofmann, Silke C., Baltaci, Mehmet, Schaller, Jörg, Hellmich, Martin, Goltzheim, Luise Stach, Assaf, Chalid, Oellig, Frank, Michalowitz, Alena‐Lioba, Helbig, Doris, Kreuter, Alexander
• Format: Article
• Language: English
• Subjects: atypical fibroxanthoma; Biomarkers, Tumor - analysis; CD14 antigen; CD34 antigen; CD99 antigen; cutaneous sarcoma; Cytokeratin; Dermatofibrosarcoma protuberans; Desmin; Diagnosis; Diagnosis, Differential; Histiocytoma, Malignant Fibrous - diagnosis; Humans; Immunohistochemistry; pleomorphic dermal sarcoma; Procollagen; Retrospective Studies; Sarcoma; Sarcoma - diagnosis; Sarcoma - epidemiology; Skin cancer; Skin Neoplasms - diagnosis; Skin Neoplasms - epidemiology; Skin Neoplasms - etiology; spindle‐cell tumors; Terminology
• ISSN: 1610-0379; 1610-0387
• DOI: 10.1111/ddg.14911

Summary Background and objectives In recent years, considerable insight has been gained into the pathogenesis, diagnosis and treatment of cutaneous sarcomas, including atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). Both entities have shown increasing incidence rates in the last decade. This study was initiated to evaluate how these new insights impact the number of diagnoses of AFX/PDS compared to other cutaneous sarcoma entities. Patients and methods In a retrospective study of four German skin cancer centers, all histopathological reports of cutaneous sarcomas (AFX, PDS, dermatofibrosarcoma protuberans, cutaneous leiomyosarcoma, angiosarcoma, and Kaposi sarcoma) confirmed by board‐certified dermatopathologists were analyzed during a time‐period of seven years (2013–2019). Additionally, utilization of immunohistochemical markers (including pan‐cytokeratin, S100, desmin, CD34, CD10, procollagen‐1, CD99, CD14, and CD68) as an adjunct to diagnose AFX/PDS was recorded. Results Overall, 255 cutaneous sarcomas were included in the present study. The diagnosis of a cutaneous sarcoma has consequently risen from 2013 to 2019 (from 16 to 52 annual cases). The results of AFX/PDS revealed 4.6 times more diagnoses in 2019 than in 2013. Atypical fibroxanthoma represented the most common subtype, displaying 49.3 % of all diagnosed cutaneous sarcomas. Additionally, the increase of AFX/PDS was linked to the use of immunohistochemistry, with specific immunohistochemical markers used in 57.1 % of cases in 2013 compared to 100 % in 2019. Conclusions This retrospective study of four German skin cancer centers demonstrates a substantial rise of AFX/PDS, possibly due to recently established diagnostic and terminology standards. This rise is probably linked to increased utilization of specific immunohistochemical markers. Atypical fibroxanthoma/PDS may be more common than previously thought and seems to represent the most frequent cutaneous sarcoma subtype.