There are 80,000 new cases of primary brain tumors diagnosed every year in the United States. About 26,000 of these cases are of the malignant variety – and John McCain unfortunately joined their ranks last week. In cancer, fate is defined by cell type, and the adage is of particular relevance here.
Cancer is akin to a mutiny arising within the body, formed of regular every day cells that have forgotten the purpose they were born with. In the case of brain tumors, the mutinous cell frequently happens to not be the brain cell, but rather the lowly astrocyte that normally forms a matrix of support for brain cells. Tumors made up of astrocytes are called astrocytomas. Classification schemes for brain tumors in the era of molecular subtypes has grown enormously complex, but a helpful framework is provided by the appearance of these tumors under a microscope. Grade 1 tumors are indolent, with little invasive capacity, while Grade 4 tumors are highly invasive, marked under the microscope as dense, sheets of cells that can even be seen to grow their own blood supply. Senator McCain has a grade 4 astrocytoma, otherwise known a a glioblastoma (GBM) – the worst kind. Social media from all sides of the political spectrum lit up with well wishes – with most casting the disease as something to be defeated.
John McCain is an American hero & one of the bravest fighters I've ever known. Cancer doesn't know what it's up against. Give it hell, John.
— Barack Obama (@BarackObama) July 20, 2017
Others within the medical community took a different take.
GBM sucks & will defeat McCain. "Get Well Soon" is misguided to point of being insensitive.This is where 'thoughts and prayers' makes sense.
— Mehreen (@GrrlMD) July 20, 2017
Mehreen is right. GBM is a deadly disease, the 5-year survival rate for patients with GBMs is <3%. The majority of GBM patients live less than a year. Yet, the medical community of neurosurgeons and oncologists that treat these tumors go to battle with these tumors. Why?
I asked a very busy neurosurgeon this same question. I asked him what he told patients. He told me that he never mentions the word cure. There is no cure. The goal is to manage the disease and buy more time.
Median survival for GBM is measured in weeks, not years. Do nothing, and expect 14 weeks; combining surgery, radiation therapy, and chemotherapy may give you 45 weeks.
What we describe is median survival, of course, and as Stephen J Gould eloquently put in his diatribe against statistics in cancer – the median is hardly the message. The oncologist you want is the one who doesn’t tell you about median survival when breaking the news to you of your cancer – she implicitly understands each GBM has a different path. Here are three such paths.