The major theme of this supplement, which is sponsored by Macmillan Cancer Support and coedited by Macmillan's joint chief medical officer Professor Jane Maher, is the supportive and palliative care needs of a growing but poorly served population: people who are living with incurable but treatable cancer. We have brought together a collection of first-in-print papers and reprints from BMJ Supportive and Palliative Care to help the medical community understand this group better. This is currently an underexplored area of oncology, so there is limited research available. Therefore, while some of the papers relate directly to this type of cancer, others offer transferable insights from related areas of the supportive and palliative care field.

Understanding the numbers, needs and experiences of people with incurable but treatable cancer is an enduring problem. For example, existing data suggests around a third of men diagnosed with metastatic prostate cancer1 and a seventh of women diagnosed with distant breast metastases will survive at least 5 years.2 Since first recurrence in these common disease sites is often detected through blood tests or imaging—currently not routinely recorded by cancer registries—rather than biopsy, these survival rates may be underestimates. Overall, there is a lack of high-quality, long-term data on survival and quality of life, for those diagnosed with advanced disease. We also know that people with particular types of cancer, including lower-grade lymphomas, myeloma and ovarian cancer, are at a high risk of multiple recurrences, but we do not fully understand who will be affected or how.

We believe that the number of people living with advanced cancer is growing, survival is increasing and for many people their needs will be similar to those with other long-term conditions. We urgently need to understand the supportive and palliative care needs of this group better.

One of the …