Mucocutaneous angiosarcoma (MC-AS) versus non-MC-AS: Clinicopathologic features and treatment outcomes in 44 patients (pts).

Abstract

10091 Background: Although the entity of MC-AS is well recognized, non MC-AS is less well reported and differences between the two are not well studied. We aimed to compare the clinical presentation and treatment outcomes of pts with MC-AS vs non MC-AS seen in our centre. Methods: Single centre retrospective study. Forty-four consecutive AS pts with complete medical records were identified from our sarcoma database. MC-AS is defined as AS arising from skin or superficial mucous membranes. Results: Median age of all pts was 69 yrs (range, 17-97 yrs), 59% were males, 2 pts had radiation-associated AS (both MC-AS); median follow-up was 8.9 mths. Thirty-four pts (77%) were classified as having MC-AS. Among the MC-AS subgroup, 88% of cases originated from the head and neck region; in the non MC-AS subgroup, 40% vs 20% vs 40% of cases originated from thoracic, abdominal organs and breast respectively. Compared with non MC-AS, median age of MC-AS pts was significantly higher (73 vs 42 yrs) (p<0.001) and more MC-AS pts were males (68% vs 30%) (p=0.064). Non MC-AS pts had significantly higher rates of metastatic disease at presentation (60% vs 15%) (p=0.008). Of 17 pts who underwent surgery as part of primary local control with known surgical margins, only 12% achieved microscopic negative margins, with no significant difference between the 2 groups. Sixteen patients with measurable disease received first line chemotherapy, 75% paclitaxel, achieved an overall response rate of 38% which did not differ significantly between the 2 groups. Median overall survival (OS) for the entire cohort was 10 mths, 9.5 mths vs 11.3 mths in pts with non MC-AS vs MC-AS respectively (p=0.894). Conclusions: Angiosarcoma is a rare disease with distinct clinical subsets and poor overall prognosis. Despite having a higher rate of metastatic disease at presentation, non MC-AS was not associated with a worse OS than MC-AS. This could be explained in part by the significantly older age at presentation of MC-AS potentially limiting use of aggressive multi-modality therapy in this pt population. These results also highlight the limitations of standard clinical staging tools in stratifying pts for survival within the MC-AS subgroup of pts.