Why Is Cancer Often Detected in the Middle or Late Stages? What Can We Do Beyond Routine Checkups?

You may wonder –

Many people have routine physical examinations every year, and their medical reports all look fine, but why do some people still get diagnosed with cancer suddenly, and often it’s already in the middle or late stages when detected?

Is there a way for us, as ordinary people, to prevent cancer or to detect and treat it before it progresses to the middle or late stages?

Today, let’s discuss this topic.

Cancer cells are “immortal”

Cancer (also known as tumors) originates from the body’s own tissue cells, which grow uncontrollably and can metastasize to other parts of the body.

Normal human cells have a finite lifespan, they are only allowed to grow when needed, and when the cells age or are damaged, they receive a “signal” to die. This “life and death regulation” is controlled by special gene fragments carried by the cells.

The signals within cancer cells have changed, allowing them to grow indefinitely.

Table 1: Normal Cells vs. Cancer Cells

Figure 1: The Life of Normal Cells and Cancer Cells (National Cancer Institute)

Why do some people still get diagnosed with cancer late despite having annual physical examinations?

Tumors have few symptoms in the early to middle stages. Consider when humans are infected with pneumonia, they exhibit symptoms such as coughing, sputum, fever, chest pain, and fatigue. These symptoms are a result of the immune system detecting the pathogens and mounting an immune response. It can be understood that these pathogens are easily identified by the immune system.

On the other hand, cancer cells can conceal themselves or release certain “signals”, causing the human immune system to turn a blind eye to them, growing, spreading, and eventually metastasizing without detection.

The tumors we can detect early include breast cancer, thyroid cancer, and gastrointestinal tumors because some grow on the body surface and are easy to find, while others can be discovered by endoscopy.

The reasons why some tumors are difficult to detect in time with routine examinations include:

For further reading 👉: Only 2 out of 100 tests are accurate?! Correct cancer screening is important!

What else can we do besides routine physical examinations?

Therefore, the methods we currently have to effectively screen and reduce the overall mortality rate of tumors are:

Methods that can reduce the mortality rate of specific populations include:

These measures together can essentially allow one-third of cancer patients to be cured after early detection
.

Figure 2: 10-year survival rates of cancer patients detected at early and late stages (National Cancer Center, Japan)

What are the causes of cancer,

and can it be prevented?

In addition to the difficulty in detection, the reason why humans still find it hard to fully conquer cancer is also due to its difficulty in prevention. The root of prevention lies in eliminating harmful factors and the links in disease production. For example, the prevention of the original COVID-19 strain is effectively suppressed by a combination of measures such as staying at home, social distancing, safety protection, and vaccines.

However, the causes of tumors are complex. Essentially, a tumor is a mistake in the genetic material (genes) of a human cell’s stored information (mutation), thus possessing the characteristics of “Table 1” and thereby harming human health.

In summary, the causes of this process can be divided into two categories: one is innate, and the other is acquired later in life.

Innate gene mutations come from parents and often lead to a higher incidence of hereditary tumors, accounting for about 10-20% of all tumors
.

Acquired mutations are related to factors such as smoking, radiation, viral infections, air/chemical pollution, obesity, hormones, chronic inflammation, and lack of exercise.

Furthermore, tumors are most likely to occur in individuals over the age of 65, as the body’s functions decline, the cumulative errors in genetic material increase, and the body’s “error correction” ability decreases, which is also one of the significant reasons for the high incidence of tumors. This is the origin of the saying that “there were not so many cancers in the past because people did not live as long as they do now”.

More complex still: the occurrence of tumors is essentially a result of the accumulation of the above multiple factors, and avoiding one or a few factors does not completely prevent the occurrence of tumors. Consider, what are the chances that we can avoid all of the above reasons?

Therefore, based on current data, about 40% of tumors can be prevented: the figure below shows that as long as you do not smoke, maintain a healthy weight, eat healthily, do not drink alcohol, exercise regularly, and get vaccinated against hepatitis B and HPV (women), you can significantly reduce the associated lung, colorectal, breast, liver, cervical, and prostate cancers.

Figure 3: Cancer risk factors (American Association for Cancer Research)

For tumors that cannot be effectively screened and prevented,

how should they be managed?

Apart from a few areas of the human body (such as hair, nails, lens, eardrum, and teeth) that do not develop tumors, other parts can, resulting in a wide variety of symptoms and signs, if these symptoms persist without improvement or disappearance, it’s time to consult your doctor for a check-up:

Finally, wishing everyone good health, enjoy your meals, and stay strong~