**3. Lymphoma**

Lymphoma is a broad term used to describe a variety of neoplasms due to proliferation of lymphoid cells. Traditionally, lymphoid neoplasms that presented with bone marrow and blood involvement were referred to by the term *leukaemia* and those that presented with a mass would be called a *lymphoma*. However, it is now appreciated that any *lymphoma* can present with or evolve in to a leukaemic picture and occasionally, *leukaemia* can present with a mass lesion.
