107 The incidence of angiosarcoma, a rare and aggressive vascular cancer, has been on the rise in the US, doubling between 2001 and 2019. A recent investigation has shed light on this trend, highlighting the challenges posed by the disease’s complexities and its link to prior cancer treatments. The findings were published in the journal Oncology. Angiosarcoma can manifest in any part of the body, but most cases occur in the skin, subcutaneous tissues, or breast. The study, which reviewed nearly 20,000 cases diagnosed between 2001 and 2020, revealed that secondary angiosarcomas, particularly in women previously treated for breast cancer, significantly contribute to the increasing numbers. The disease often develops as a consequence of radiotherapy or chronic conditions such as lymphoedema. Researchers observed a consistent annual increase of 1.6% in the adjusted incidence rate, which stood at 3.3 cases per million person years in 2019. The rise in secondary angiosarcoma cases among women was especially pronounced, with chest wall, breast, and upper extremity cancers seeing the largest growth. In contrast, primary angiosarcoma cases have remained relatively stable. The study underscores a concerning disparity in the disease’s presentation. Women are far more likely than men to develop secondary angiosarcoma in specific regions, such as the breast and chest wall. These findings align with the known risks associated with radiotherapy for breast cancer, which remains a crucial treatment option but carries potential long-term consequences. While cutaneous and breast angiosarcomas are more commonly diagnosed, visceral angiosarcomas, affecting internal organs like the liver, heart, and bones, are also increasing. Although these cases represent a smaller proportion, their growth rate mirrors that of cutaneous forms, raising questions about potential underlying causes, including evolving cancer treatment protocols. The study’s authors emphasise the need for vigilance and early detection, particularly among high-risk individuals. For patients with a history of cancer, awareness of angiosarcoma’s symptoms – ranging from persistent swelling to unusual skin changes – can be crucial for timely diagnosis and improved outcomes. Advances in molecular biology have begun to unravel the genetic underpinnings of angiosarcoma, offering hope for targeted therapies. Yet, the disease’s rarity poses challenges for large-scale clinical trials, which are essential for developing effective treatments. To address this, researchers advocate for subtype-specific trials that consider the disease’s molecular and anatomical diversity. The findings also highlight the importance of balanced decision-making in cancer treatment. With the increasing recognition of secondary cancer risks, clinicians are exploring ways to refine radiotherapy protocols, potentially reducing exposure for older patients or those with low-risk disease profiles. As angiosarcoma cases continue to rise, the need for heightened awareness among clinicians and patients is clear. Early detection, coupled with evolving treatment strategies, may offer a pathway to better outcomes for those affected by this rare but devastating disease.