494 Low plasma fibrinogen levels are associated with poor prognosis in cutaneous angiosarcoma of the head and neck

Abstract

Angiosarcomas are malignant vascular tumors that account for 2% of all soft-tissue sarcomas. Due to the rarity of angiosarcomas, the prognostic factors are seldom reported. Here, we investigated plasma fibrinogen levels as a prognostic factor for angiosarcoma of the head and neck (ASHN). This retrospective study reviewed a cohort of patients histologically diagnosed with ASHN at Nagoya University Hospital between April 2006 and July 2019. The 22 patients with ASHN included in the present study. The cutoff value of plasma fibrinogen levels was determined to be 257 mg/dL. The Kaplan–Meier curve showed the OS rate to be significantly higher in the high plasma fibrinogen group than in the low plasma fibrinogen group (p=0.0027). The univariable model showed that patients with low plasma fibrinogen levels had a significantly poor OS [hazard ratio 6.78, 95% confidence interval 1.63 to 28.2, p-value of 0.008503]. Recently, high plasma fibrinogen levels were reported to predict poor prognosis in several malignancies. Unexpectedly, the present study suggests that low plasma fibrinogen levels predict poor prognosis. ASHN is an extremely hemorrhagic tumor. From repeated microbleeds and blood coagulation in ASHN lesions, plasma fibrinogen is considered to be consumed and to decrease in patients with ASHN. Therefore, we speculate that the reduced plasma fibrinogen levels might reflect tumor burden indirectly. In conclusion, the present study suggests that pre-treatment plasma fibrinogen levels are a useful prognostic factor for ASHN that may reflect tumor burden.