Dermatofibrosarcoma protuberans: Clinicopathological spectrum with emphasis on lymph node metastasis and fibrosarcomatous transformation

Introduction

Dermatofibrosarcoma protuberans (DFSP) is an uncommon skin tumor with a low-to-intermediate grade of malignancy, characterized by progressive growth and a propensity for local recurrence. In this series, we are analyzing the clinicopathological spectrum of DFSP cases.

Materials and Methods

A retrospective study of 12 patients with DFSP who were diagnosed at our institute over the last 2 years (2018-2020) was performed.

Results

The clinicopathological spectrum and immunohistochemistry of DFSP cases were studied with one case with lymph node metastasis, which is a rare entity, and two cases of the fibrosarcomatous DFSP were also diagnosed and warrant a special mention.

Conclusion

Pathologists should be aware of metastasis and unusual variants while reporting dermatofibrosarcoma.

Dermatofibrosarcoma Protuberans: One Centre Experience

Background: Dermatofibrosarcoma protuberans (DFSP) is a rare soft tissue tumor that is classified as a non-melanoma skin cancer. Surgical excision with wide safety margins is the cornerstone treatment and frequently requires advanced reconstruction methods for wound closure. This study aimed to report our experience with the management of seven consecutive patients with dermatofibrosarcoma protuberans. Materials and Methods: We performed a retrospective study of seven consecutive patients with dermatofibrosarcoma protuberans admitted to our Plastic and Reconstructive Surgery Department of Clinical Emergency Hospital "Prof. Dr. Agrippa Ionescu" Bucharest, Romania, between July 12, 2018, and July 4, 2022. Results: The mean age of the patients was 38.2 years. In 4 patients, the primary treatment consisted of wide local excision, while 3 presented to our clinic for re-resection. All cases required complex reconstruction methods 3 patients with a split-thickness skin graft (STSG), 3 patients with local flaps, and in one patient, because of the superior size of the post-excisional defect, we used local advancement flaps and STSG. In two cases, the histopathological diagnosis revealed fibrosarcomatous differentiation (the largest primary tumor dimension), one of which showed fascial invasion, and both of them received adjuvant radiotherapy. Conclusion: A soft tissue tumor with a clinical appearance suggestive of DFSP, especially in cases of increased tumor sizes, incisional biopsy and subsequent multidisciplinary approach will lead to a wide surgical excision with negative histopathological margins, as a standard treatment, for a lowgrade sarcoma, which rarely metastasizes.

Dermatofibrosarcoma protuberans with fibrosarcomatous transformation: a case report

Dermatofibrosarcoma protuberans is a quite rare local aggressive tumor of dermis and subcutis, revealing characteristic morphology and chromosomal translocation (17; 22)(q21;q13) with gene fusion COL1A1-PDGFB. The tumour almost never metastasizes and complete excision signs an excellent prognosis. Approximately in 10% of cases, dermatofibrosarcoma undergoes a fibrosarcomatous transformation associated with metastatic disease and worse prognosis. In this paper, we refer a case of a male patient with subcutaneous tumor in back region, in which the small biopsy lead to diagnosis of a spindle cell sarcoma. However, only the histopathological examination of the entire tumor in the material from the radical surgery detected the dermatofibrosarcoma protuberans with fibrosarcomatous transformation. Both components of the tumor showed the characteristic genetic alteration. Identification of fibrosarcomatous component within the DFSP matters in prognosis. Distinction between fibrosarcoma arising within the dermatofibrosarcoma protuberans and fibrosarcoma arising de novo is of therapeutic consequence: the patients with metastatic or inoperable DFSP with fibrosarcomatous transformation may profit form imatinib treatment.