Dermatofibrosarcoma protuberance in a black African cohort-a clinicopathologic study

Abstract

Background: Dermatofibrosarcoma protuberance (DFSP) is the commonest, yet rare, dermal sarcoma globally. There are few reports in the literature of this neoplasm in Nigerians and indeed in sub-Saharan Africa. This study documents our institutional practice observation and compares it with those from other regions of the world.

Methods and materials: This study was a retrospective review of all cases of histologically diagnosed DFSP at the University College Hospital, Ibadan, Nigeria, spanning a period of 27 years (January 1989-December 2016). Data on patient age, gender, tumour location, size, tumour recurrence and metastasis status were obtained from clinical and surgical pathology archival files and records.

Results: Sixty-nine cases of DFSP were recorded over the period reviewed with a male-female ratio of 1.6:1. The mean age of the study population was 39.6 years. The youngest patient was 5-year old, while the oldest was 86 years and the modal age group was the 4th decade. The trunk was the commonest anatomic tumour location. Recurrences were seen in seven cases with recurrence interval ranging from 6 to 240 months. The correlation between tumour size and age was non-significant (r = -0.183; p = 0.182). There was fibrosarcoma-like transformation in three cases (4.3%) studied.

Conclusion: Dermatofibrosarcoma protuberance is rare in our population and occurs more commonly in males and on the trunk. Recurrence can occur beyond the recommended follow-up period of 10 years.

Keywords: Black Africans; DFSP; Nigeria; clinicopathologic; dermatofibrosarcoma protuberance; sarcoma.

Figure 1.. Number of patients per each decade of life.

Figure 2.. (A) Haematoxylin and Eosin (H&E) x40; Low power view with the tumour in the dermis. (B) (H&E), ×40; The deep margin of resection with tumour infiltrating adipocytes. (C) (H&E), ×100; Prominence of the marked cellularity of the tumour. (D and E) (H&E), ×400; Typical morphology with cartwheel arrangement of the spindle tumour cells with collagenous stroma more prominent in E. (F) (CD34), ×400; Strong staining of the spindle cells with the collagenous stroma unstained and prominent vascular channels highlighted by CD34.