Vascular Growth in Lymphomas: Angiogenesis and Alternative Ways

SIMPLE SUMMARY: Angiogenesis is the main mechanism for the formation of new blood vessels in tumors. Recent studies also described alternative non-angiogenic ways that play an important role in tumoral resistance to anti-angiogenic therapies. Lymphoma cells can induce the formation of new blood vessels via both angiogenic and non-angiogenic mechanisms. Despite the numerous discoveries regarding lymphomas’ pathogenesis, less is known about these processes and their role in tumoral initiation and progression. This review discusses the current knowledge on vessel formation in lymphomas, highlighting the potential implications for prognosis and treatment. ABSTRACT: The formation of new blood vessels is a critical process for tumor growth and may be achieved through different mechanisms. Angiogenesis represents the first described and most studied mode of vessel formation, but tumors may also use alternative ways to secure blood supply and eventually acquire resistance to anti-angiogenic treatments. These non-angiogenic mechanisms have been described more recently, including intussusceptive microvascular growth (IMG), vascular co-option, and vasculogenic mimicry. Like solid tumors, angiogenic and non-angiogenic pathways in lymphomas play a fundamental role in tumor growth and progression. In view of the relevant prognostic and therapeutic implications, a comprehensive understanding of these mechanisms is of paramount importance for improving the efficacy of treatment in patients with lymphoma. In this review, we summarize the current knowledge on angiogenic and non-angiogenic mechanisms involved in the formation of new blood vessels in Hodgkin’s and non-Hodgkin’s lymphomas.