Why Do Cancer Treatments Fail?

Cancer treatments often fail, especially in the advanced stages.
This is seen as a major shortcoming of the medical system and may even lead to the emergence and propagation of conspiracy theories.
Below, we describe the major reasons for treatment failure in cancer patients.

1. Cancer's Complexity: Nature of the Beast

Cancer is much more than just some random cells that have stopped listening to the body.

By the time cancer becomes detectable, it has already made millions of copies and formed specialized units.

It can keep on multiplying without stop. It can create new blood vessels. It can reprogram the energy production system and direct all energy supplies towards itself. It can recruit normal body cells and use them to shield itself from body defenses. It can colonize newer body organs and dictate their functioning. It conquers the body forming a tumor micro-environment and by playing with hundreds of body's original signaling pathways.

To understand this you may compare it to the climax scene of science fiction movie "Robot" where the small but fierce robot units converted them into a big enough unit capable to face all dangers. Image below:

Cancer is not just few random cells, instead, it is like millions of cancer cells on a mission

2. Limitations of Cancer Treatments

Lack of targeted treatments and toxicity due to administration of non-targeted treatments

Chemotherapy and generalized radiation therapy cannot differentiate among normal tissue and cancer. Toxicity to normal tissues produces severe side effects and may even lead to discontinuation of treatments.

Even many biological treatments and many monoclonal antibodies could similarly be non-targeted and may produce severe side effects.

Poor treatment plan
Treatments may address just one or two dimensions of cancer and not give cancer a 3-D or a 4-D fight.
Patients or doctors may opt for only a single or few modes of therapy due to costs, personal preferences, and lack of comprehensive treatment planning.
Unfortunately, sometimes this may also be due to missing scientific guidelines and consensus.

3. Individual Patient Characteristics

Surgical in-operability of the tumor

Certain tumors have size, shape, and growth in such a manner that they cannot be safely and completely removed from the body. They may be approaching a major blood vessel or be adhered to major organs preventing their removal.

Coexisting diseases

Co-morbidities such as diabetes, obesity, heart disease, etc. when present along with in a cancer patient worsen the chances of success. The more the number and severity of such diseases, the poorer the chances of success are.

Inadequate symptom control

Depression, fatigue, pain, loss of physical strength due to cancer impact the motivation and if not successfully controlled can reduce the chances of treatment success.