About rare prostate cancers
Although prostate cancer is a common cancer in men, there are different types of prostate cancer, and some of these are rare. Because they are rare, we don’t know as much about them. If you are diagnosed with one of the cancers mentioned here, speak to your doctor or nurse about what that means and what treatments are suitable for you.
Like most things in our body, the prostate is made up of different types of cells (see image below). The type of cancer that develops depends on the cell it starts in.
The most common type of prostate cancer starts in some of the cells that line the prostate, called glandular epithelial (gland) cells. There are two types of gland cells – basal cells and luminal cells (see image). Prostate cancer can develop in either of these cells.
When we talk about common prostate cancer here, we mean this type of prostate cancer. You may hear it called adenocarcinoma or acinar adenocarcinoma or see this written in your biopsy results (your 'pathology' report).
Some men have more than one type of prostate cancer. For example, they may have some common prostate cancer as well as a rare cancer.
Some of the rare cancers may be more aggressive than common prostate cancer. This means they may grow faster and are more likely to spread outside the prostate.
Some of the tests used to diagnose prostate cancer may not be as good at picking up rare prostate cancers. For example, some rare prostate cancers – such as small cell prostate cancer – don’t cause your PSA level to rise, so they’re not always picked up by a PSA test. Because of this, some rare cancers may not be diagnosed until after they have spread outside of the prostate.
These different types of prostate cancer look different under a microscope, so may be picked up after having a biopsy to check for prostate cancer, or surgery called transurethral resection of the prostate (TURP) to treat an enlarged prostate. Rare cancers aren't always given a Gleason score after a biopsy. This is because they can behave differently from common prostate cancer and can’t be measured in the same way.
Because rare cancer can be aggressive and spread outside the prostate, you will probably have more tests, such as a CT scan, an MRI scan or a bone scan, to check if it has spread.