AJSP2401 - CME/CMLE - 168 Cases of aneurysmal dermatofibroma and 29 cases of hemosiderotic dermatofibroma-168 Cases of aneurysmal dermatofibroma and 29 cases of hemosiderotic dermatofibroma

168 Cases of aneurysmal dermatofibroma and 29 cases of hemosiderotic dermatofibroma

Pdf Summary

A recent study conducted by Akana Nishimoto and colleagues reveals new insights into aneurysmal dermatofibroma (ADF) and hemosiderotic dermatofibroma (HDF), two rare subtypes of dermatofibroma (DF), a common benign skin tumor. The research utilized a retrospective analysis of 2,128 DF cases from 2016 to 2019 at Nippon Medical School Musashi-Kosugi Hospital to explore the clinicopathological characteristics of ADF, HDF, and other DFs. The key points include:<br /><br />1. **Incidence and Demographics**:<br />   - ADF accounted for 7.9% and HDF for 1.4% of the cases. <br />   - Both ADF and HDF showed lesser female preponderance compared to other DFs.<br />   - Patients with ADF and HDF had similar mean ages (41-44 years) and both subtypes had larger lesion sizes and increased cellularity compared to other DFs.<br /><br />2. **Site and Diagnosis**:<br />   - ADFs are more common on exposed body areas like the face and forearm, while HDFs showed a significant preference for the lower leg, 41% of HDFs occurred on the lower leg.<br />   - Presurgical diagnoses frequently labeled ADF and HDF as dermatofibroma. Only one ADF case was misdiagnosed as a malignancy (basal cell carcinoma).<br /><br />3. **Etiology and Pathogenesis**:<br />   - Traditionally, HDF is considered a precursor to ADF. However, this study suggests that ADF might arise from ordinary DF due to physical trauma, potentially evolving into HDF.<br />   - Another possibility is that venous stasis contributes to HDF, particularly for lesions on the lower leg, with all lower leg HDFs showing venous stasis changes.<br /><br />4. **Histopathological Findings**:<br />   - Both ADF and HDF demonstrated different histopathological features, including frequent occurrence of keloidal collagen in ADF (16%).<br />   - Some overlap between DF variants was observed, with HDF frequently showing foam cells and monster cells.<br /><br />5. **Implications**:<br />   - The study challenges the traditional belief of HDF progressing into ADF, proposing a potential reversed relationship or a dual-pathogenesis model involving physical trauma or venous stasis.<br />   - The findings underline the importance of recognizing these variants, as they may mimic more serious conditions like melanoma or Kaposi sarcoma.<br /><br />This study highlights the complexity and varied etiology of DF subtypes, emphasizing the need for further research to understand their precise pathogenesis and clinical management better.

Keywords

Aneurysmal Dermatofibroma

Hemosiderotic Dermatofibroma

Dermatofibroma

Clinicopathological Characteristics

Retrospective Analysis

Nippon Medical School

Incidence and Demographics

Histopathological Findings

Physical Trauma

Venous Stasis