When the Distinctions of Cancer Blur

Pictured: George Plitas

Surgical oncologist and scientist George Plitas

We start with a tumor. How it is found varies: The patient felt it, the physician felt it, a scan picked it up, or maybe it was found accidentally while looking for something else. At this point it has no name, it’s just a tumor, which is a term used for a mass of tissue that is not normal.

How does a tumor get a name? It first needs to make its way to a pathologist’s microscope. It can be a piece of the tumor from a biopsy or sometimes the whole thing, removed by a surgeon. The pathologist then begins the naming process. At first it’s a general description of size, color, and consistency, and then the examination becomes progressively more detailed and specific.

The cells and the pattern they make are carefully detailed. Sarcomas, for example, are often composed of cells that are long and thin, classically described as spindle shaped. Clustering together, these cells form sinuous whorls that appear as if they were created from the brush of Edvard Munch. A tumor at this stage of classification may graduate to be called cancer, based on numerous characteristics such as how abnormal the cells are or if they invade adjacent structures such as nerves, lymph channels, or blood vessels.

At this point, the tumor generally is given a name. Sarcoma, carcinoma, and lymphoma are among the most common, but there are numerous others with multiple subclassifications. To achieve a level of even greater certainty, the pathologist tries to determine the normal tissue from which this tumor originated. Sarcomas for instance can come from muscle, bone, nerve, and even fat. Breast carcinoma for the most part originates from the glands of the breast, and it can be further localized to either the ducts or the lobules that together make up the functional unit of a breast gland.

Improving the Accuracy of the Diagnosis

Apart from the gross, or general, description (the size, color, and consistency) and the microscopic appearance, an added level of accuracy is obtained by using special stains to determine what proteins the tumor cells are making. Why such detail? It has broad implications for prognosis and treatment. The detailed pathologic description of a tumor allows one to use databases to estimate, with ever-greater accuracy, the probability of recurrence, metastasis, and survival.

The naming process for a tumor is critical for dictating patient care.
Surgical oncologist and scientist George Plitas

Work by investigators from Memorial Sloan Kettering and elsewhere has revealed genetic alterations that are specific to individual subtypes of cancer; many of these alterations can be targeted both experimentally and clinically. These findings are the basis of numerous promising clinical trials that are available only to patients whose tumor has been classified and given a specific name. The naming process is therefore critical for dictating patient care.

Back to top

The Challenges of Metaplastic Tumors

As a breast surgeon at Memorial Sloan Kettering, I see patients with breast carcinoma and breast sarcoma, but upon occasion the line gets blurred. There is a category of breast tumors with characteristics of both sarcoma and carcinoma. These are described as metaplastic, meaning that one form is turning into another.

Some are more carcinoma like and others are more sarcoma like. For instance, they may have the characteristic waves of long spindly cells seen in sarcoma but a special stain will indicate that they originated from a breast duct, typical of a carcinoma.

How we treat a sarcoma is very different from how we treat a carcinoma. Sarcoma rarely makes its way to the lymph nodes but carcinoma frequently will, and so further surgery is performed to examine the lymph nodes in the armpit of patients with breast carcinoma.

The chemotherapeutic regimens are also very different. Entry into clinical trials for either sarcoma or carcinoma is not available to patients with these confused tumors. Patients and their doctors are left unsettled, as there is no answer for the most basic of questions: What is it?

Our lack of understanding is not without consequences, since these tumors recur with an unacceptable frequency after they are removed.

Back to top

Assigning an Accurate Name

Giving an accurate name to these metaplastic tumors will involve defining their biology. To do this, a number of cutting-edge techniques can be used to systematically reveal the tumor’s exact genetic and metabolic abnormalities. Although figuring out which side of the fence these tumors sit on will have important implications for the people who have them, it also gives us an incredible opportunity to learn something about cancer.

As mentioned above, metaplasia implies a state of flux or plasticity. If these tumors are becoming sarcomas, then we have a window of opportunity to learn about that process. Are all sarcomas born sarcomas, or were they something else beforehand? Can we turn them back? Can understanding the process of this metamorphosis reveal weaknesses that can be targeted?

James Baldwin, writer, civil rights activist, and victim of cancer, said, “Know from whence you came. If you know whence you came, there are absolutely no limitations to where you can go.” While he certainly was not referring to metaplastic breast tumors, his words hopefully still apply. Understanding the dynamic processes of change within these tumors will undoubtedly yield more than just a name.

Back to top

George Plitas is a surgical oncologist who specializes in the treatment of patients with breast tumors. His current work in the laboratory is focused on ways in which the immune system can be activated to specifically target cancer. This piece was adapted from an article that originally appeared in Sarcoma Update, a newsletter published by the Kristen Ann Carr Fund.


Commenting is disabled for this blog post.

I have triple-negative metaplastic breast cancer. Did chemo, double mastectomy and then radiations. My question is they told me that's it, now we watch. Isn't there some kind of follow-up testing that could or should be done?

Dear Chris, there aren’t any specific follow up recommendations for metaplastic breast cancer versus other histologic subtypes. We recommend that you follow up with your oncologist for specific follow-up tests he or she thinks may be necessary for your particular circumstances. Thank you for reaching out to us.

I have had a sarcoma as well as a metaplastic breast tumor. Treated by Dr. Singer at Sloan Kettering. For sarcoma.
Both spindle cells...always thought they could be related but told not so. .
DOING fine 7 years, and four years out from treatments.

Dear Carol, we are glad to hear you are doing well. Thanks for sharing your experience on our blog!

Can reactive tissue from a previous lumpectomy and radiation be confused with metaplastic breast cancer based on a stereotactic biopsy showing spindle and squamous cells.

Dear Gerry, we forwarded your inquiry to Dr. Plitas and he responded:

“Radiation can induce many histologic changes in tissues that can often be confusing to interpret on the limited material from a biopsy. The timing of the biopsy following radiation contributes greatly as the initial effects of radiation on tissue may take a while to normalize. In such situations it may be necessary to get a better sampling of tissue with an excision to better discriminate between radiation changes and a neoplastic process.”

Thank you for reaching out to us.

Dr. Alexandra Heerdt performed a mastectomy and lumpectomy on my mother at Sloan Kettering 2 weeks ago, and needs to schedule treatment for post-op treatment of spindle cell metaplastic carcinoma. Dr. Vasan was to be her oncologist, but she'd prefer the Bergen location. Are there any specific protocols that are followed for this type of cancer? Do all your locations follow the same regimen for treatment?

Dear Jill, we recommend that your mother call one of her MSK doctors to find out if the treatments she needs are available at MSK Bergen. Thank you for your comment, and best wishes to both of you.