As with many areas of medical science, the fields relating to the research and treatment of cancers are full of highly specialized terminology. Some words are used interchangeably—and seemingly arbitrarily—while others are used one way in common practice despite having very different meanings in formal practice. Oncology and hematology are often both used in discussions and literature about lymphoma, but many do not know the difference, or the proper places to use one or the other. Understanding oncology, hematology and lymphoma will make it easier to understand much of the written material on the subject.
Oncology
As a very broad field of medical study, oncology refers to the investigation of distinctive malignancies or cancers. These cancers result from genetic mutation or cellular trauma causing some cells to grow much more quickly than usual, and in a destructive manner.
For the purposes of this article, the distinctive feature of oncology as a field of study is that it treats cancers in any area of the body. These can include cancer of the mouth, throat, brain, breast, prostate, colon, lung, ovaries, or the blood. It is the last area—the blood—that links oncology and hematology, as we shall see.
Hematology
Hematology is the high-level study of the blood and the blood-forming organs, including diseases of the blood. Some of the diseases or sub-specialities studied by hematologists include the following:
So, to simply things, oncologists study cancer, which may involve the blood, and hematologists study the blood, which may be the site of cancer. Lymphoma is what happens when these two fields overlap.
Lymphoma
Along with leukemia, lymphoma is a cancer of the blood. Where leukemia attacks white blood cells, lymphoma targets the lymphocytes, elements of the body's lymphatic system. Lymphoma can, therefore, be approached and treated by either a hematologist or an oncologist, or more commonly, both. Often a hematologist will run blood tests to determine whether a cancer diagnosis in called for, at which point an oncologist will prescribe and commence treatment. As treatment progresses, both may need to remain involved in patient monitoring.
Conclusion
Oncology, hematology and lymphoma are all terms that refer to a specific thing, but the meaning of the first two terms may overlap in circumstances dealing with the third term, lymphoma. One doctor may study brain tumors and another clotting disorders. In this case, their areas of study do not overlap, but both could legitimately study lymphoma from two different areas without a conflict in definition.