ABSTRACT
Leiomyosarcoma is the second most frequent soft-tissue sarcoma. Tumor lymphocytic infiltration (TIL) and programed cell death ligand-1 (PD-L1) have been associated with prognosis in different malignancies while DNA mismatch-repair deficiency (MMR-D) has been associated with response to check-point inhibitors. In this pilot study, we sought to examine TIL, PD-L1 and mismatch-repair (MMR) protein expression in 11 leiomyosarcoma and its association with outcome as potential biomarkers for adjuvant treatment. Eleven primary leiomyosarcoma archived-tissues were analyzed for expression of MMR proteins (MSH2, MLH1, MSH6 and PSM2), PD-L1 expression and PD-1, CD3 or CD8. MMR-D was detected in tumor tissue from 2/11 leiomyosarcoma patients. CD3 T-cells were present in all samples, whereas CD8 staining was positive in all but one. PDL-1 was positive in 4/11 and PD-L1 in 6/11. Interestingly, the three patients with the poorest outcome had strongly positive staining for PD-L1 and CD8 while in the two patients who are alive and recurrence-free, both PD-L1 and CD8 infiltration were lacking. We found an association between tumor infiltrating CD8 cytotoxic lymphocytes, strong PD-L1 staining and survival; suggesting a role as biomarkers for treatment decisions regarding peri-operative chemotherapy. We also identified MMR-D in two patients with leiomyosarcoma comprising 18% of our sample.
ABSTRACT
A limited number of chemotherapeutic agents have been found to be active against advanced soft-tissue sarcomas (STSs), particularly sarcomas that have progressed following doxorubicin treatment. The aim of this retrospective study was to determine the response to treatment with gemcitabine plus paclitaxel in patients with STSs. Data were collected on all patients with advanced non-resectable STS who were treated with a fixed dose 700 mg/m2 gemcitabine in combination with 70 mg/m2 paclitaxel on days 1 and 8 every 3 weeks. A total of 30 patients were included, with a median age of 56.4 years (range, 40-70 years). The gemcitabine/paclitaxel combination was well tolerated, with an overall response in 27% and a clinical benefit in 57% of the patients. The median progression-free survival was 6.1 months and the overall survival was 14.3 months. In conclusion, gemcitabine plus paclitaxel was found to be tolerable and effective in patients with advanced STSs.
