Overcome the Challenges of Cancer Care. M. D. Rosenberg
can help us find cancer before a patient has symptoms.
There are lots of types of screening tests for various types of cancer, depending on a person’s age and risk factors. Some tests, such as mammograms (breast cancer screening), are recommended by almost everyone. Others, such as PSA tests (prostate cancer screening), are controversial.
How do you know whether a screening test is recommended? The US Preventive Services Task Force (USPSTF) is a group of experts that gives grades to screening tests. Grade A means they recommend its use for the general public. Grade D means the task force recommends against using a particular test. Here are some common screening tests:
1 Breast cancer screenings with mammograms, age 50 to 74: Grade B
2 Colon cancer screenings with colonoscopies, age 50 to 75: Grade A
3 Prostate cancer screenings with PSA: Recently changed from Grade D to Grade C
4 Lung cancer screenings with CT scans, age 55 to 80: Grade B
5 Skin cancer screenings with regular skin exams: Grade I—unable to make a recommendation
Screening recommendations are constantly evolving as new information becomes available—as we saw with prostate cancer screenings. Unfortunately, some screening programs are effective but have not been widely adopted (like lung cancer screening) for a variety of reasons. This may be due to a lack of knowledge or resources. For many types of cancers, such as lymphoma, we don’t have good screening tests. For other cancers, even if we find them early, we don’t have good treatments (like pancreatic cancer). This is frustrating for patients, families, and doctors. Doctors are moving toward more screening and prevention to improve outcomes for patients.
To look at the screening tests available for all sorts of diseases, check out the USPSTF website, listed in the resources at the end of this book.
Cancer or an Infection?
Making Sense of a Symptom
Let’s go over a common clinical scenario. Bob notices a swollen gland in his neck. He notices slight discomfort with swallowing. He can see inside his mouth in the mirror, and his throat looks slightly red. But he figures he just has a virus and it will go away after a week or two. He has some soup and fluids and rests. His symptoms don’t go away, and he goes to the doctor. The doctor checks his neck and is slightly concerned. The doctor writes a prescription for antibiotics, thinking this is bacteria, not a virus, causing the swelling. The gland shrinks down after two weeks. Bob is back to his old self.
Sarah, who works with Bob, also notices a swollen gland in her neck. She has some pain in the area, and she figures it could be a virus. She gives it a week to get better, but it doesn’t. The swollen gland just gets bigger. She goes to the same doctor as Bob. The doctor figures there’s a strong possibility she caught the same bug, given that she works with Bob. She also has a red throat and some pain in the gland area. She is given the same antibiotics as Bob, but after three weeks, her swollen glands have only gotten bigger.
The doctor orders a biopsy. This involves taking a piece of tissue with a needle and looking at it under a microscope. The biopsy shows she has cancer. Sarah is frustrated, as she wasted one week at home and three to four weeks on antibiotics before the diagnosis of cancer.
It’s understandable why Sarah would be mad or distraught. But as you can see, it can be hard to distinguish between these two ailments based on symptoms.
Why the Glands Are Swollen
Have you ever had a sore throat with swollen glands?
Those swollen glands are called lymph nodes. Lymph nodes are home to the immune system, and they reside all over your body. There are hundreds of them in the neck alone!
When a person is exposed to a virus or bacteria (an invading microbe), the immune system takes that infection to a lymph node. In the lymph node, the white blood cells (immune cells) present the invader to the rest of the immune system. The immune system will then be able to recognize the invader throughout the rest of the body.
Priming of the immune system (exposing it to the bacteria) leads to swelling of the lymph nodes. This is because the immune cells are growing and getting ready to spread throughout the body to hunt down the bacterial invaders. In response to an infection, lymph nodes often seem red, are painful, and may even be hot to the touch.
So what does this have to do with cancer? As we know, cancer cells find organs in which they can grow and flourish. Like the liver or lungs, a lymph node is just another organ where cancer can grow. The organ is like soil for a seed—only this organ is spread all over your body. Many cancers will communicate with the immune cells of the lymph nodes, allowing the cancer cells to take over.
As cancer cells take over the lymph node, the gland swells just like when you’re sick from a bacterial infection. But there’s one key difference: Cancer cells want to avoid the immune system, so they disguise themselves (see chapter 2). Even though cancer grows and fills up a lymph node, the immune system doesn’t recognize it’s there. There is no immune reaction. It’s like the cops don’t recognize the bad guys!
Cancer often presents with swollen glands, but the lymph nodes are often less painful than they’d be with an infection (sometimes they’re even painless!). Still, the similar symptoms can make it difficult to distinguish between cancer and an infection.
Red Flags: Symptoms that Call for a Closer Look
If a patient presents with a painless swollen gland or a painless mass, this is often a red flag for doctors. A red-flag symptom is of particular concern to doctors; it’s a symptom that’s more worrisome than the average symptom we see in clinic.
Red-flag symptoms may include headaches that wake someone up at night, unexplained night sweats or weight loss, and painless swollen masses, among others.
Notice how many of these red-flag symptoms are nonspecific. They might not even signal a cancer diagnosis; they could be caused by something else. A red-flag symptom is only one piece of a puzzle. Having one of these symptoms does not mean a person has cancer.
What red flags do offer is a key but subtle way to figure out whether a patient has something like Bob (an infection) or Sarah (a cancer). This method isn’t perfect. Some patients have both a cancer and an infection. In fact, some cancers make getting an infection more likely. Again, this is why diagnosing cancer is so hard (and why doctors go to school for so long).
Starting the Workup
Once a patient shows up with a red-flag symptom, doctors pursue a diagnostic workup.
A red flag prompts a doctor to do a more thorough investigation. This includes taking a comprehensive medical history and performing a physical exam. Doctors will often order some basic blood work. These tests look at whether the patient’s blood carries enough oxygen (based on the number of red blood cells), is able to fight infections (based on the number of white blood cells, which are the immune cells), and clots correctly (based on the number of platelets).
If doctors suspect a certain type of cancer, they may order a test for tumor markers. Tumor markers are proteins that leak out into the blood from tumors. We can then measure the levels of these proteins in the blood.
Most cancer markers are nonspecific. Therefore, they aren’t good for screening a population (people) for cancer (see the earlier section on cancer screenings); the markers may be elevated even when there is no cancer. But doctors may use tumor markers to narrow down the possible types of cancer if they suspect a certain cancer in a patient.
Getting a Biopsy
We all have normal lumps and bumps in our bodies. These are found everywhere and are a normal part of existence. So how do we tell if something is a normal bump or cancer?
If