Pleomorphic dermal sarcoma (PDS) is a rare dermal malignancy most commonly affecting sun exposed areas of males in their 7th and 8th decade of life.(1) There is evidence that the incidence of dermal sarcomas are increasing in Oceania.(2) Of this rare group of tumours, PDS is perhaps the least well understood. We conducted a review of the evidence for management of these rare tumours.
A literature review of articles relating to pleomorphic dermal sarcoma was conducted. The results were limited to english language publications in the past 5 years.
The was a dearth of literature on incidence of PDS, however a 2019 study found the cumulative incidence of dermal sarcoma in Australia to be 2.09/100 000, with PDS the third most common subtype. Management involves radical excision with a 2cm safety margin decreasing the risk of local recurrence.(3) The evidence for adjuvant therapy is unclear, with one study finding a trend to decreased recurrence, however the subgroup included only 11 patients. Anti-PD-1 inhibitors may be effective with several case reports showing complete response even in metastatic disease.(4, 5) Overall recurrence rates vary with studies ranging from rates of 5-28%, the wide range appears to emphasize the importance of local control at time of excision.(6) There is no consensus for follow-up, with one recently published guideline suggesting serial clinical examination and ultrasonography of the scar.(7)
While PDS is rare, the incidence of dermal sarcomas in Oceania appears to be increasing. Surgical excision is currently the mainstay of treatment with emerging evidence for radiotherapy. Medical therapies such as anti-PD1 inhibitors show impressive results in small numbers of case reports however more research is required.