Why do illnesses recur?

Why do illnesses recur?

There is always a risk for people who have survived cancer that the disease will recur and that is frightening. Furthermore, when compared to healthy people, they have a much larger risk of developing tumours in other parts of the body. I know a man who had colon, thyroid, kidney and basal cell skin cancer and he’s still alive to this day. There are many such cases, so why does this happen? We can partly explain this with a body’s predisposition to developing tumours and specific environmental or biological factors. In any event, statistics show, for example, that cancer-afflicted babies who have been successfully treated are much more likely to get another oncological disease later in their lives, than healthy children. The same can be said of adults.

Initial treatment didn’t destroy all cancer cells

This is one of the most common explanations why patients experience a recurrence. The goal of therapy in oncology is to eradicate all cancer cells. However, this isn’t always possible and we have an even smaller chance of being certain that it has. That means that theoretically even if we destroy 99.99% of the cancer cells, the remaining 0.01% are enough to, under the correct circumstances (another illness, a low immune system, severe emotional stress, etc.), once again become active and create new clones of themselves.

During an operation, the surgeon attempts to remove the entire tumour. These days the incisions are always examined to see if any cancer cells have remained. This is done by a pathologist who examines the tissue under a microscope either next to the surgical theatre or in a laboratory. If tumour cells aren’t found in the incisions, then the surgery is considered complete and the surgeon closes the incision. However, there’s always the possibility that cancer cells remained in a part of the tissue that wasn’t examined. On the other hand, if cancer cells are found, the operation is expanded, within reason, to further areas until cancer cells are no longer found. The success of the operation is also limited by the fact that some cancer cells may have already migrated to other tissues. I’ll go into more detail about the role of surgery in the complex treatment of tumours in a later blogpost.

Even by administering radiation to the tumour or its location after an operation, we can’t guarantee that all of the cancer cells have been completely destroyed. It turns out that different tumour cells also react differently to radiation. Moreover, this is also influenced by other factors including blood flow to the tissues of the tumour, their oxygenation and if the cells are actively dividing or if they’re in the so-called dormancy phase. The fact that radiation can’t eradicate 100% of cancer cells is demonstrated by the recurrence of the disease in places that have been directly irradiated. However, administering radiation to the scars, the places where the tumours originally existed or the regional lymph nodes can significantly reduce the likelihood of a later recurrence of the tumour in its initial location.

Chemotherapy is most effective against cells that are actively dividing. Normal, healthy cells have a resting phase between every division. For cancer cells this phase can be slightly shorter. Therefore, chemotherapy is administered according to specific intervals of time in the hope that as many cells as possible can be destroyed while they’re in the process of dividing. For example, cells that were in the so-called resting phase during the first course of chemotherapy may be in the process of dividing when the second course is administered and therefore destroyed. In this way, we destroy more and more new cancer cells with each new course of chemotherapy. However, chemotherapy is toxic to humans and can’t be administered indefinitely, which is why it’s possible for some cells to avoid this trap and remain alive. Unfortunately, we can’t guarantee that chemotherapy will destroy all cancer cells. We have to trust that the immune system will be better equipped to tackle this enemy army. Therefore, one of the biggest challenges we face in treating cancer is not to completely weaken the immune system during chemotherapy, so it can be capable of fighting the disease afterward.

I’ve noticed that patients often think that targeted therapy is a kind of treatment that only affects a specific target, usually the tumour itself, but not healthy cells. However, this is not the case. The majority of targeted therapy drugs affect specific receptors or proteins on the surface of cells either blocking their ability to divide or destroying them. Because tumours are heterogeneous and consist of different cells, we can achieve a considerable reduction in the size of a tumour mass using such methods, but we still can’t guarantee that the disease won’t return. Essentially, we should constantly change the drugs we use for treatment to destroy as many cells as possible. This can be achieved in many cases by prescribing a variety of different drugs, but it turns out that this approach doesn’t always work.


Tumours become resistant to drugs

Surgery is the only treatment method, which doesn’t face the problem of resistance. Unfortunately, sooner or later resistance becomes apparent in many different drugs used to treat cancer. This is largely attributed to the tumour’s genetic instability and the creation of more new, yet slightly different clones. The new mutations in the cancer cell can also be the reason why previous drug therapies are no longer as effective as they were in the beginning. Resistance to all kinds of therapies has been observed including chemotherapy, hormone therapy, targeted drug therapy and immune therapy (checkpoint inhibitors). Thankfully, we have access to a wide variety of drugs, so changing specific drugs often helps. However, sometimes tumours are simultaneously resistant to a number of different drugs. This is referred to as multiple drug resistance and this makes our goal much more complicated. It has also been observed that cancer cells have the ability to expel unwanted guests (drugs) from their territory and then the drugs can longer reach their target.

An internal or external shock

The interaction between the tumour and the body’s micro- and macro environment is very complicated and is still not completely understood. There are many questions which still remain unanswered. However, it’s in these sophisticated relationships that the disease’s uniqueness is hidden.

It could be a slight exaggeration, but I tend to believe that cancer is in some ways a psychosomatic illness. This isn’t just my own personal observation, because I’ve also read about many other such cases. Case in point, over two thirds of patients have had a severe shock or trauma within two years of being diagnosed with cancer and these can include the loss of a loved one or a job, divorce, deep disappointment, prolonged distress, environmental changes, another acute illness, a severe offense, an inability to forgive or failure in one or many spheres of life. Large or small shocks are a part of everyday life. The only question is how we deal with them. The same can be said of the recurrence of the disease. Everything appears to be fine, the tumour is in its early stages and adequate therapy has been administered, so nothing bad should happen. Then suddenly – a shock or trauma and the disease returns. I usually tell patients and students that all of our heads are as big as they are and that all centres – breathing, heartbeat, metabolism and the centres which control our emotions – are closely connected to one another. For this reason I recommend that my patients seriously consider these factors and, if necessary, find help, so they don’t end up digging their own graves by dwelling on their sorrow and anguish. There’s a reason why we say that bright, optimistic people fare better with their illnesses and live longer and better lives than pessimists.


Our immune systems are so complex, multifunctional and in constant interaction with so many of our body’s processes and external stimuli that the very notion of improving our immune systems sounds impossible. Many patients often ask me how they can improve their immune systems, especially after finishing courses of therapy, when a patient thinks that something has to be done to prevent a recurrence of the disease. People usually think that this is something simple – I’ll take some pills and the problem will be solved. In reality, everything is much more complicated and we can’t always correctly interpret laboratory results to properly assess the true condition of the immune system. In such cases, I usually recommend an immunologist, who will first evaluate the immune system and only then prescribe any supplements or medications. However, people often become the victims of advertisements. If the bottle or box indicates that it will strengthen immunity or even prevent cancer, people are willing to buy it at any price. I don’t discount the possibility of a placebo effect, which is largely dependent on how much a patient truly believes that the given medication will help. This is why I’ve become quite tolerant of this scenario. I just make sure that these supposed immune system improving medications aren’t used too often. After all, supplements contain biologically and chemically active substances. Therefore I recommend that no more than three different active substances, which should be changed every once in a while, are used at once.


Doctors often use this word to denote the state when a person has finished treatment, appears to be healthy and is expected to be healthy for years to come. But no doctor can claim, hand on heart, that the disease will not return. It’s possible that cancer cells still remain in your body in very small amounts, which can’t be detected and which, for the time being, don’t cause any complaints or symptoms. It’s possible that these cells are dormant, meaning that they aren’t actively dividing and don’t currently pose a threat to the body. That is until something occurs that could awaken them from their slumber. It has been observed that in the majority of cases, tumours recur within the first 2 years after an operation. After that, the risk of a recurrence becomes less likely with each passing year. Five-year survival rates are only a surrogate indicator, because they only indicate that a patient is still alive. However, the majority of patients want to live long and healthy lives and not just 5 or 10 years. Unfortunately, the disease has a tendency to return even much later – after 15, 20 or even 30 years. Sometimes it’s difficult to reconcile oneself with the idea that the disease might return, which is why we must do everything within reason to ensure that we don’t provoke it with our behaviour. For example, we can definitely help ourselves by making sure that we adopt a healthy lifestyle and that we find a way to calm or at least balance our psycho-emotional state. In Latvia, the Dzīvības koks (Tree of Life) support group offers a number of ways to prevent you from remaining alone in the dark, such as summer camps, group activities and other opportunities.

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