# Characteristics, Outcomes, and Risk Factors in Primary and Secondary Angiosarcoma: A Retrospective Cohort Study

## TL;DR

This study examines primary and secondary angiosarcomas, finding that secondary cases are more common and identifies risk factors affecting survival rates.

## Contribution

The study provides insights into the prevalence and risk factors of primary and secondary angiosarcomas using a single-center cohort.

## Key findings

- Secondary angiosarcomas are more common, especially after breast cancer radiotherapy.
- Nicotine use and prior carcinoma history affect 1-year survival rates.
- Diabetes mellitus may influence 5-year survival but requires further study.

## Abstract

Angiosarcomas (ASs) are a heterogeneous subtype of soft tissue sarcomas. They can be subdivided into primary and secondary AS, with secondary AS being predominant, particularly those following radiotherapy. The aim of this study was first to analyze our patient cohort on a descriptive level and then to identify possible risk factors with regard to one and 5-year survival using logistic regression.

The study was designed as a retrospective, single-center cohort study. All patients with histologically confirmed AS over 18 years of age were included in the study. Binary logistic regression was used for univariate analysis screening of continuous or dichotomous variables, respectively. For multivariate analysis, binary multivariate logistic regression was performed to assess independent associations between chosen variables and AS.

A total of 39 patients were included in this study. 14 (35.9%) had primary and 25 (64%) had secondary AS. Women were more frequently affected (76.9%) than men (23.1%). The 1-year survival rate was 87.2%, and the 5-year survival rate was 51.3%. In the logistic regression analyses, nicotine consumption and a history of carcinoma were identified as significant factors influencing the 1-year survival rate. For the 5-year survival rate, only breast cancer was found to be a significant influencing factor in the univariate analysis. Based on univariate logistic regression, all variables with a p value of < 0.1 were chosen to be included into multivariate analysis. The multivariate analysis showed diabetes mellitus (p=0.067) with an association to influence the 5-year survival rate.

We were able to show that the proportion of secondary ASs is predominant. These occur after radiation treatment of the breast. Diabetes mellitus may be associated with reduced 5-year survival, although this finding did not reach statistical significance and requires further investigation. Due to its small sample size, this study should be regarded more as hypothesis-generating.