D., a forty-five-year-old teacher, feels a lump in her breast. She has surgery to remove the mass, and the pathology shows a lymphoma. D. is surprised and asks, “Do I have breast cancer?” The answer is no, she has lymphoma of the breast, not breast cancer.
Her staging workup, treatment options, and prognosis will follow the principles established for lymphoma, not those for breast cancer. She will not have to undergo more surgery to test the lymph nodes in the armpit for cancer in a procedure termed axillary lymph node dissection; she will not need a bone scan to check for metastatic cancer affecting the bones.
These might have been done had D. been diagnosed with breast cancer.
Instead, she will undergo CT scans of the chest, abdomen, and pelvis, lymphoma-directed blood work, a bone marrow biopsy, and possibly a PET scan to stage the lymphoma fully and plan for its treatment.
I bring D. case up to illustrate that many kinds of cancer can arise from the same location in the body. The type of cancer that develops depends on the specific cell type affected by the cancer process.
Because every organ and gland in our body is made up of a variety of cell types, several kinds of cancer can occur in any region. For most sites in the body, one type of cell is usually affected, resulting in the common types of cancer that are most often talked about. For example, breast cancer arises from the cells of the breast glands and is more specifically described in a pathology report as “breast carcinoma.” When less commonly affected cells are struck by cancer, then one of the rarer cancers occurs, such as a lymphoma or sarcoma of the breast. These principles will become clearer later.
Although there are hundreds of distinct types of cancer, I group them here into four main categories for ease of understanding:
1. Carcinomas
2. Hematologic malignancies (blood and lymph cancers)
3. Sarcomas
4. Brain tumors
I encourage you to read about each type of cancer even though you may be interested in just one kind. The more you know about cancers and their properties, the better you will understand the specific cancer(s) you may encounter.
