diagnosis

What are tumor markers?

What are tumor markers?

They are proteins that are shed by cancer cells in greater numbers than normal cells. These would be desirable as screening tests because blood tests can measure their circulating levels.

 

None of them have proven their benefit in saving lives due to early diagnosis. Their value lies in measuring response to treatment in advanced cancers, once the cancer has been diagnosed and treated.

What is Grade and Differentiation?

Additional tests you will see on the Pathology report:

Grade: describes the activity of the nucleus. A normal cell has normal activity of the nucleus. A cancer cell nucleus looks different. A grade 1 nucleus is less in disarray than a Grade 3 nucleus. The higher the grade, the worse the cell behaves.

Differentiation: is a measurement of how closely the cancer cell resembles the parent cell or the cell of origin.

What is Cancer Staging?

Cancer Staging:

The next step is to stage the disease. The classical way of staging the disease depends on T (tumor size) N (number of lymph nodes involved with cancer) and M (presence of distant disease). This TNM classification provides the basis of the staging system. The bigger the T, the greater the number of involved lymph nodes, the presence of metastatic disease increases the stage from the lowest (and best) of 1 to the highest (worst) of 4.

How are you diagnosed?


Mr X is at least 15 kg/ 32 lbs overweight. He has been trying to lose weight for many years, but has had a tough time. He doesn’t have time to exercise, and has periodically tried diets without much success. About 6 months ago however the weight started coming off and he was quite pleased. He was feeling full faster, but didn’t pay much attention to it.  He thought he had finally got control of his big apetite. At his next physical, his primary doctor found a 40 lb weight loss since his weight one year ago. She was surprised, given his many previous years of lack of  success in this department. She was concerned and started doing some investigation. He was diagnosed with stomach cancer.
Ms Y has had  chronic cough for many years. She is a long time smoker, started as a teenager, sneaking them in after school, growing into a pack a day habit. She is used to waking up in the morning and trying to hack up the phlegm every day. In the last few weeks she has noticed that she is bringing up some blood with it. Just a tea spoon or so, but that is new, and she is alarmed by it. She reports it to her primary doctor and has a chest X ray. She is diagnosed with lung cancer.
Mrs C has had bowel problems on and off. She has chronic constipation, and has had to take laxatives on a regular basis. Her doctor has been recommending a colonoscopy since she turned 50, but she has resisted it. She has heard bad things about the test and doesn’t want to do it. Lately, however, she has increasing difficulty in going to the toilet. She finally agrees to a colonoscopy and is diagnosed with colon cancer.
Ms B is very good about her annual mammograms, particularly since her neighbor was diagnosed 10 years ago. She also examines her breasts the first day of every month. This year, they found a small shadow in her right breast, and called her back for more magnified views. They did a biopsy and found an early stage Breast Cancer.
These are some of the many different ways that cancer is diagnosed. Sometimes it does not cause symptoms and is only diagnosed at an early stage by Screening tests. These are tests that are recommended in the general population, even without any symptoms. They have been proven to be effective in detecting small cancers when they are in a curable stage. They have an impact on life expectancy.
Currently, the only tests that have had population wide benefits have been
mammograms to detect early stage Breast Cancer
Pap smears to detect Cervical Cancer
Colonoscopy/ stool testing for Colon Cancer
A PSA blood test to detect Prostate Cancer is used commonly in the United States, but has not been proven to have life saving benefits. Many leading Prostate Cancer experts do not use it on themselves, as it is unclear whether it is essential to treat early, asymptomatic Prostate Cancer. The treatment causes many side effects, and if the disease is slow growing, can be deferred. This is a topic for ongoing discussion, and will be addressed in the future.
Similarly, screening tests for ovarian cancer have also been unsuccessful in picking up early disease. CA 125 is a useful test to follow the course of the cancer after it has been diagnosed, but is not useful to detect it early.
Recently, a study was published which showed benefit of screening lung CT scans with low dose radiation to detect early cancers in high risk patients, mainly smokers. Risks and benefits of this are currently being weighed.
So, apart from these cancers which are detected by screening tests, people are mainly diagnosed when they present to the doctor with an unexplained pain, weight loss, bleeding, bowel or bladder changes, cough, shortness of breath, etc.
The doctor then starts an investigation ,which results in blood work/ CAT scans and finally a biopsy. That begins a journey into the cancer world