First report on two cases of pleomorphic dermal sarcoma successfully treated with immune checkpoint inhibitors

Abstract

Pleomorphic dermal sarcoma (PDS) is one of the most common sarcoma of the skin. Currently, limited treatment options exist for advanced stages of the disease. While immune checkpoint inhibitors (CPIs) have revolutionized cancer treatment options-their efficacy in PDS has not been explored yet. Here, we present two advanced PDS cases that showed response to anti-PD-1 therapy. Patient A had a locally metastasized PDS and reached a complete remission of the disease after eight cycles of Pembrolizumab. Patient B developed an inoperable relapse of PDS with a complete remission of the disease 4 months after treatment with Pembrolizumab in combination with radiotherapy. To our knowledge, this is the first report of two individuals with advanced PDS that successfully underwent anti-PD1 treatment. By comparing the immune micromilieu to a previously published cohort, we show that the two cases are representative for PDS tumorspotentially making these results more generalizable.

Data driven precision medicine: who is the driver?

“…treatment options, including immune-checkpoint inhibition, as well as iii.) PDGFRB as a potential diagnostic biomarker for PDS, complementing previous studies [ 8 , 9 ].…”

Clinicopathological and Genomic Profiles of Atypical Fibroxanthoma and Pleomorphic Dermal Sarcoma Identify Overlapping Signatures with a High Mutational Burden

“…High TMB is known to be associated with a better response to immunotherapy with checkpoint inhibitors (CPI) such as anti-PD-1 and anti-PD-L1 across diverse tumor entities [ 42 ]. Interestingly, a case study reported that two patients diagnosed with advanced PDS and high TMB have been successfully treated with anti-PD-1 (Pembrolizumab, (KEYTRUDA ® MSD Kenilworth, NJ, USA).…”

“…Another patient with an inoperable relapsed PDS (TMB 77.997 mt/mb) treated with Pembrolizumab for four months, similarly showed a complete response. However, this patient received additional radiotherapy, introducing an additional factor potentially influencing treatment response [ 42 ]. Pembrolizumab is approved for other UV-induced skin tumors, such as malignant melanoma [ 43 ].…”

Complete response of metastatic pleomorphic dermal sarcoma to anti‐PD‐1 therapy

“…A PET scan 3 months after commencement of therapy demonstrated a complete response with regression of all sites of metastatic disease (c, d), which is ongoing. This case adds to the evidence that anti‐PD‐1 therapy can be highly effective in patients with advanced PDS 1,2…”