Enlarged lymph nodes on CT in the pelvis can be present because of infections, inflammatory conditions, cancer, or even medications. Enlarged lymph nodes in the pelvis are those which are abnormally shaped or larger than typical. Unfortunately, distinguishing those lymph nodes that are from benign conditions and cancer may not be possible without biopsy.
Multiple markedly enlarged lymph nodes in the pelvis that are greater than say 2 centimeters and matted raise concern for something like lymphoma. Lymphoma is a blood cancer and can be limited to the nodes or involve structures outside the lymph nodes. Lymphoma staging often involves imaging the body with CT or PET scan.
Spread of cancer to the lymph nodes in the pelvis is another cause of enlarged lymph nodes. Many types of cancer produce enlarged lymph nodes in the pelvis on CT but some of the more common ones are prostate cancer, gynecological cancer, and cancers of the extremities. Often there will be a history of cancer or associated findings.
Enlarged lymph nodes in the pelvis on CT can be seen with systemic infections like HIV/AIDS which can cause lymphadenopathy in the body. Autoimmune conditions like lupus or arthritis like rheumatoid can cause lymphadenopathy. Infections like Syphilis, flu, fungus can cause more generalized lymph node enlargement.More systemic conditions will result in more generalized enlarged lymph nodes not isolated to the pelvis.
Enlarged lymph nodes in the pelvis are common when there are infections or inflammatory conditions of the legs and feet. Ulcers or infections of the skin result in enlarged lymph nodes on CT. These infections will often be apparent to the clinical doctor.
Enlarged lymph nodes in the pelvis on CT can therefore have many causes. When lymph nodes are markedly enlarged and matted, than lymphoma becomes the main consideration. Enlarged lymph nodes can also occur because of spread of cancer, infections, inflammatory conditions or more generalized illnesses. It is often not possible to tell the cause of the lymph node enlargement without a biopsy. Other imaging tests and clinical history can help in some cases.