Do Leukemia and Lymphoma Show Up in Plain X-rays?

Doctors examining x-ray
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Neither leukemia nor lymphoma is diagnosed by imaging. Initial diagnosis typically requires biopsy and a number of laboratory tests that are performed on the blood and tissue samples. Imaging tests for leukemia, in particular, may not be as helpful as in other types of cancer that form tumors.

That said, even in leukemia, and often in lymphoma, plain x-ray images can offer clues that, taken together with other bits of information, may be part of the workup that ultimately leads to a biopsy and a diagnosis.

With respect to lymphoma, the patterns of lymph node involvement, which may be revealed even by chest x-rays, can be very important initially to help narrow down the possibilities. Not all swollen lymph nodes in the chest are lymphoma. Other cancers, infection, and nonmalignant diseases like sarcoidosis may be to blame. Sometimes swollen lymph nodes are in easily accessible locations for biopsy, such as the neck; however, in other cases—in Hodgkin lymphoma, for instance—the only cancerous lymph nodes might be located deep within the chest.

X-ray Images in Leukemia - Bones and Nodes

X-rays, or plain films, are not used to diagnose leukemia. However, a chest x-ray might be done to check for a lung infection or for some other reason, and the x-ray might also show swollen lymph nodes and other areas of disease. Some forms of leukemia may spread to the lymph nodes as the disease progresses. Leukemia can also produce changes in the appearance of bones in affected adults and children.

Osteopenia refers to bones that do not appear as dense—not as brightly white in images—as normal, but are not to the extent seen in osteoporosis. Osteopenia is a frequent finding in myeloma, leukemia, lymphoma, and many other disorders.

In addition, radiologists, or doctors who interpret radiographic imaging, look at the patterns of disease involvement, or lesions, in the bone.

Leukemia and many non-cancerous diseases that interfere with bone metabolism, such as hyperparathyroidism and osteoporosis, may have a symmetrical distribution in the skeleton. In contrast, a haphazard, asymmetric appearance of bone lesions may suggest a different cause, such as Paget’s disease of the bone or metastatic spread of some other kind of cancer.

X-ray Images in Hodgkin Lymphoma - Enlarged Nodes in the Chest

The two main types of lymphoma are Hodgkin lymphoma, or HL, and non-Hodgkin lymphoma or NHL. Again, as with leukemia, the lymphoma is not diagnosed by x-ray.

However, chest x-rays might be ordered for a variety of other reasons, and some 40 to 65 percent of people with HL have cancer involvement within the chest, or thorax, at the time of diagnosis; of these, more than 90 percent have what’s known as mediastinal lymph node involvement. Mediastinal lymph nodes are lymph nodes located in the mediastinum. The mediastinum is an area in the central part of the chest in between the two lungs.

HL most often involves the lymph nodes in an area of the mediastinum called the superior mediastinum—that is, specific groups of lymph nodes with names like prevascular, paratracheal, and aortopulmonary lymph nodes.

On plain x-rays, lymph node enlargement within the mediastinum can appear as either a one-sided abnormality or an abnormality on both sides of the mid-line of the chest. With a Hodgkin’s-type pattern of lymph node involvement, when multiple involved lymph nodes may be seen together, this can look like elongated connection of lobes. When the cancerous lymph node or mass does not have a clearly defined border, this can indicate invasion or extension into adjacent lung tissue.

NHL may also produce lymph node enlargement in the chest, but NHL is actually a group of different lymphomas that can start virtually anywhere—NHL does not necessarily spread from node group to node group in ordered fashion, as is more typical of HL.

Lymph Nodes on CT Scans

The appearance of involved lymph nodes on a CT scans can vary—from well defined and discrete to a more matted-together appearance. Sometimes your doctor can easily see discrete lymph nodes; other times, multiple lymph nodes may appear all together, as part of one big mass. Typical chest masses in HL show up on CT as a gray shade similar to other soft-tissues (but not fat, which is dark gray-black; and not bone, which is white) and the mass may look bumpy or have irregular contours. Although enlarged lymph nodes typically look gray, some calcification is possible, which shows up more white like bone; however, this is much more common following treatment, especially following radiation therapy.

PET and PET/CT Scans

PET scanning uses radioactive glucose that is taken up generally by many, but not all, different kinds of lymphoma cell types. The uptake of this radioactive substance can create a map of sorts, showing areas of cancer involvement in the body. PET is generally more sensitive in detecting lymphoma than CT. For instance, PET may reveal disease in normal-sized lymph nodes and help to evaluate disease that is outside of the lymph nodes, but not evident on CT. PET is often combined with CT to allow comparison of areas of higher radioactivity on the PET scan with the more detailed appearance of that area on the CT. Compared with conventional imaging, the use of PET/CT initially can influence staging and lead to a different treatment in a substantial number of cases.

Sources:

Hare SS, Souza CA, Bain G, et al. The radiological spectrum of pulmonary lymphoproliferative disease. Br J Radiol. 2012;85(1015):848-864.

Juanpere S, Cañete N, Ortuño P, Martínez S, Sanchez G, Bernado L. A diagnostic approach to the mediastinal masses. Insights Imaging. 2013;4(1):29-52.

Mehrian P, Ebrahimzadeh SA. Differentiation between sarcoidosis and Hodgkin’s lymphoma based on mediastinal lymph node involvement pattern: Evaluation using spiral CT scan. Pol J Radiol. 2013;78(3):15-20.

Tomiyama N, et al. Anterior mediastinal tumors: diagnostic accuracy of CT and MRI. Eur J Radiol. 2009;69:280–288.

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