How big is a centimeter?

A centimeter is a unit of length equivalent to 1/100th of a meter or about 0.393700787401575 inches. So how can an object half the size of a penny, smaller than an M&M or about 40% of an inch have such a dramatic impact on your life?

If it is a rock in your shoe, a zit on your cheek the day of a big date or a malignant tumor in your breast, the impact can be phenomenal and life-altering.

One of my ED MD friends sent me the National Comprehensive Cancer Network/American Cancer Society Breast Cancer Treatment Guidelines. Thanks Joe! Unfortunately for the oncologist I am going to see tomorrow, I am reading it. I am not; however, able to understand all of it. I am just a nurse practitioner and I don't have my complete pathology report in front of me. I also don't have the information related to the hormone receptivity of my tumor. That wasn't done yet. What I do know is that my tumor was grade 3, 0.9 cm with clean margins and my lymph nodes were negative. This makes my cancer a Stage I.

The documents contain multiple decision trees for treatment of the various stages of breast cancer. According to the treatment guidelines, if the tumor is less that 1 cm but has bad features (BAD tumor!) then chemotherapy is possibly indicated. If the tumor is greater than 1 cm regardless of features, chemotherapy is indicated. I guess there is some gray zone here. What is a bad feature? Is my oncologists definition of a bad feature the same as some other oncologist's?

So let's go back to considering the size of 1 cm...see above photo. What is the difference between 0.9 cm (the size of my tumor) and 1 cm. The obvious answer is 0.1 cm or 1 mm. How big is one millimeter? A millimeter is 1/1000th of a meter or 39.37×10−3  inch. The short answer is not very big! So then, how big of a difference is there in a tumor that is 0.9 cm vs. 1 cm? Again, not very much.

The medical head of mine understands that clinical treatment guidelines are based on sound evidence. Years of clinical research lead the greatest oncological minds to develop the treatment guidelines that recommend chemotherapy for tumors greater than 1 cm. I suspect that when these guidelines were developed, there was even some overlap involved. Perhaps it was determined scientifically that no chemo was needed for tumors less than 1.25 cm but to be "on the safe side" the parameter was set at 1 cm. I understand all of those things. HOWEVER, the part of my head that knows I have cancer can't help but wonder what difference 0.1 cm makes in determining treatment that could have an effect on your lifelong health and well-being.

So then, how big is 0.1 cm? It depends. It depends on which part of my brain is thinking. If it is the medical part, like the oncologist, it is not a significant difference. If it is the emotional part of my brain, the patient part that has cancer, it is an enourmous difference.