About the disease
Cancer of unknown primary (CUP) is a cancer, whose primary site, where it started is unknown. In this case it can be present in several metastatic sites. Detailed tests need to be done in order to understand the origin of the cancer. It is important for further successful treatment. After the origin is identified, cancer is renamed after the organ it started to develop in. In some cases it is impossible to identify the origin of cancer. Nevertheless, even in this cases treatment can be successful. According to American Cancer Society, around 2% of all cancers are represented by CUP. Overall, over the past ten years, incidence of CUP decreased by 35%, which is good news. Mortality rate over this time also decreased almost by 42%.
Because of the fact that CUP can originate in any part of the body, it is difficult to tell its exact causes. It is believed that smoking, DNA mutations, poor nutrition, excessive ultraviolet radiation, obesity are responsible the most for development of CUP. Various researches show that it most often originates in stomach, colon, and ovaries. It can also start to develop on skin, which in this case is called melanoma.
Symptoms of unidentified cancer can be various as they depend on the organs, which they spread to. Nevertheless, there are several symptoms, which proved to be common for most patients with CUP, and if you have any of those, you need to contact your doctor.
- Swollen lymph nodes in different parts of the body
- Skin tumors, which are manifested as skin bumps
- Shortness of breath
- Pain in the abdomen
- Bone pain, if cancer spread to the bones
- Weight loss
- Loss of appetite
Diagnosis of CUP is in most cases complex, as doctors have to check each organ of the patient to identify the origin of cancerous growth.
- X-Ray is used to get images of all inner organs.
- CT scan and MRI produce more precise images, which can also identify cancer origin.
- Biopsy examines sample tissue of affected organs where doctors suspect the cancer to be the most.
- Bone marrow aspiration is used, if patient has severe bone pain.
- Blood test is used to examine blood cells.
- Surgery is used if cancer was found in one organ or in lymph nodes and it can be removed completely. Nevertheless, there is always a possibility that cancerous cells are also present in another organ.
- Radiation is used to slow the growth of cancer and stop it from spreading further. A patient may need to undergo either external or internal radiation to kill as many malignant cells as possible.
- Chemotherapy can be used in combination with surgery and radiation. It can also be used if those treatment methods can no longer be applied and in this case chemo is used to relieve the symptoms and prolong patient's life.
In general, in most cases doctors are able to identify the origin of unknown primary cancer and thus chances for recovery become higher. Even if the origin was not identified, but unknown primary still has not progressed very much, you have high survival chances.