Adenoid cystic carcinoma (ACC) is a relatively rare but life-threatening cancer that occurs mainly in the glands that produce our saliva. However, even though it is more common in salivary glands, ACC can develop in many other organs, including the breast.
Salivary gland ACC is considered a difficult cancer to manage and to predict the outcome of the disease in any one patient. The main issues are the risks of late recurrences (more than 10 years after the initial diagnosis) and dissemination to other parts of the body (distant metastasis), including lung, bones and brain. Also, a major problem is the lack of drugs that have a significant impact on disease progression for patients with advanced disease. Patients diagnosed with breast ACC, on the other hand, have a better chance of remaining free of disease for longer periods or never experiencing relapse or dissemination. Scientists still don’t fully understand why ACC in the salivary glands and the breast have different behaviours.
Rare cancers, such as ACC, combine the challenges of being both a rare disease (limited scientific data and professional expertise) and cancer (complex tumour biology and resistance to conventional therapies). In many cases, patients with rare cancers have to deal with uncertainties from diagnosis to treatment. Being diagnosed with a rare cancer usually means that it is harder to find doctors who have expertise (often having to travel long distances to access treatment) and, due to the lack of scientific evidence, doctors disagree more often regarding the best treatment available. For physicians, rare cancers are more difficult to handle: there is less evidence to support clinical decisions and, in many cases, less personal experience.
SALMYB is a basic-science research project designed to expand our knowledge of this disease. ACC has an associated, recurrent molecular event, chromosomal translocation. This means that a piece of one chromosome, at a specific gene sequence, breaks off and attaches to another chromosome, at another specific gene sequence. In ACC the main genes involved with the translocation are MYB and NFIB. To date we do not understand the full implications of this translocation and the biological implications of the joining of these two genes, however, it is thought that the MYB gene may allow cells to maintain an undifferentiated status, more embryonic-like,which would allow tumours to form, grow and migrate to other sites in the body. Our investigation, studying the biological impacts of the translocation, contributes to the understanding of ACC development benefiting patients suffering from this rare form of cancer at different primary sites.
