Too small too accurately characterize is a term that radiologists use for liver spots that are less then a centimeter or smaller. The term means that we can’t say for sure what the spot is because it’s too small. These are common everyday type findings that many people have on CT. Majority of the time they are benign and nothing too worry about. This is especially true if you are healthy and don’t have cancer or liver disease.
Most of the time, darker spots in the liver under a centimeter are cysts. By darker, I mean that it looks darker then the liver, kind of like a cyst would look like. With larger cysts, it’s possible to measure the density and determine the spot is filled with fluid. For tiny dark spots, it’s tough because the density can’t be measured as accurately.
For most people, these dark liver spots are benign. These may be of more concern in patients who have a history of cancer. Since spread of cancer can look like dark spots, this becomes a possibility. In practice, it is more common to discover metastasis or spread of cancer that are larger then a tiny little spot and look worrisome. Even in cancer patients, these tiny dark spots can be benign. The ones that are metastasis are often not fluid density and may have irregular borders or complex appearance. They don’t usually look like a simple cyst.
In cases where it is not clear what a tiny dark spot is, an MRI of the abdomen may help. Additionally a short term 3 month follow up will be helpful. Cancer will grow over 3 months in many cases, while cysts grow very slowly or do not change much. Tiny little dark spots in the liver can be liver tumors as well, but this is uncommon in my experience.
How about bright tiny spots in the liver? By bright, I mean brighter then the liver. Again, these will most likely be benign, especially if your healthy. In healthy patients without cancer or liver disease, these will be benign tumors that can be left alone like hemangioma. They can be followed over time to make sure they don’t grow or change in any way. This can be done every 6 months to a year.
If you have cancer then a metastasis or spread of cancer is a possibility for a bright spot in the liver. In many cases, there is more then one tiny bright spot, and they are of differing sizes. There may also be spread elsewhere in the body. In cases that are not clear, an abdominal MRI can be done or a short term 3 month follow up. Cancer will grow while benign tumors will not or grow slowly.
Tiny bright spots in patients with liver disease like cirrhosis also becomes more concerning. Patients with cirrhosis are at greater risk of liver cancer. Liver cancer can present as a tiny sub centimeter bright spot. This is not a very common presentation in my experience. A closer look at the bright liver spot can be obtained with an abdominal MR. liver cancer classically will be bright early during scanning with intravenous contrast, and then become dark later.
Therefore, tiny spots in the liver that are too small to accurately characterize are often benign. The interpreting radiologist can’t say for sure what they are. In some cases, a more aggressive approach is taken for them. This is especially true for patients with cancer of liver disease. Further workup can include abdominal MR, short term follow up or PET scan. Your doctor will determine the best approach based on your particular circumstances.