Skip to content
Prof. Dr. Mustafa Özdoğan · Medical Oncologist

Why Is There No Certainty in Cancer Treatment?

Why Is There No Certainty in Cancer Treatment?
In this article

The Truth Within Uncertainty: Why Are There No “Definite” Answers on the Cancer Journey?

The silent question most often echoing through oncology clinics is: “Doctor, will I definitely recover?” Medicine’s response in probabilities rather than “Yes” or “No” is not a failure of communication, but biological honesty. This article provides a comprehensive discussion of the scientific foundations of uncertainty in oncology.

 Genetic and Epigenetic Heterogeneity: “Chaos Within the Tumor”

Cancer is not a homogeneous mass consisting of a single cell type. Intratumoral Heterogeneity is the name given to a situation in which even cells within the same tumor may have different genetic characteristics.

  • Spatial Variation: Cells on the right side of a tumor may be sensitive to a drug, while those on the left may be resistant.
  • Temporal Variation: While the dominant cell population dies when treatment begins, cells in the minority that are resistant to the drug may multiply over time and change the course of the disease.

This biological diversity is the most fundamental barrier to predicting a “definite outcome.”

 Individual Biology and the “Microenvironment” Effect

Not only the tumor, but also the “soil” in which it lives—the human body—is variable. Cancer cell behavior is closely tied to the patient’s Tumor Microenvironment.

  • Immune Response: Even if two patients’ tumors are genetically identical, one patient’s immune system may recognize the tumor better while the other’s may be suppressed.
  • Metabolism and Age: Liver function and coexisting conditions such as diabetes or hypertension directly affect how quickly chemotherapy drugs are broken down in the body and how effective they are.

 Statistical Probabilities vs. Individual Fate

Oncology literature speaks in statistical concepts such as “Median Survival” and “P-value” . But statistics apply to large groups, not to a single individual.

When a doctor says “70% success,” it means: “This treatment was successful in 70 of 100 people with characteristics similar to yours.” However, no biological method has yet been discovered to know in advance whether a patient belongs to that group of 70 or the remaining group of 30.

“Statistics are medicine’s compass, but every patient navigates their own sea alone.”

 Biological Evolution and Treatment Resistance

Cancer cells are dynamic structures programmed to survive. Just as bacteria develop resistance to antibiotics, cancer cells evolve under treatment-related Selection Pressure .

Clinical Reality: Even after a “Complete Response” (complete disappearance of the tumor), dormant cells may remain at a level too small for imaging to detect (micrometastatic). It is impossible to know exactly when these cells will awaken.

 The Limits of Imaging Technologies

Advanced methods such as PET-CT, MRI and CT are excellent tools, but they too have a “resolution limit.” Clusters of cells smaller than 3-5 millimeters may generally be invisible on these devices. “Clear imaging” means “no tumor of detectable size,” rather than “no cancer cells in the body.” This small distinction is the technical barrier to speaking with certainty.

 Balancing Clinical Benefit and Quality of Life

Success in cancer is more than “tumor shrinkage.” Sometimes a treatment shrinks the tumor while worsening the patient’s general condition; at other times, the tumor remains the same size (stable disease) while the patient enjoys good quality of life for years. Variation in these parameters from person to person makes it difficult to establish a “standard definition of recovery.”

 Managing Uncertainty: The Ethics of Honesty

In modern medicine, a physician’s role is to provide “realistic guidance” rather than false hope. False certainty:

  1. Causes patients to make misguided plans for the future.
  2. Undermines physician–patient trust by creating disappointment.
  3. Increases the patient’s psychological devastation if recurrence occurs.

Frequently Asked Questions

Why can’t my doctor say “You will recover one hundred percent”?
Because cancer and human biology are not static. Each cell’s response to a drug and each body’s defense mechanisms differ. Scientific honesty requires choosing the most likely path in light of the available data rather than giving an absolute guarantee.
Does a “clear” PET-CT result mean the cancer is completely gone?
Imaging devices have a resolution limit (generally 3-5 mm). A “clear” report means there is no tumor large enough for the device to detect, but it cannot rule out the presence of individual cells at a microscopic level. This is why follow-up is vital.
Why does a treatment that works well at first lose its effect months later?
This is called “acquired resistance.” Cancer cells may evolve under treatment pressure and develop new mutations that disable the drug’s mechanism. In this situation, oncologists move to different treatment options known as “second-line” therapy.
Are the “survival times” in statistics a definite timetable for me?
No. Statistical data (such as median survival) reflect the average of thousands of patients. An individual patient may fall far below or far above this average. Statistics provide only a general roadmap; they do not determine individual fate.

Conclusion and Assessment

Uncertainty in cancer treatment arises from the complexity of life , rather than the inadequacy of science. There is no certainty because every person is unique, every tumor is distinct and every treatment process is a living story.

But uncertainty does not mean helplessness. Where there is uncertainty, there is close monitoring, personalized strategies and constantly updated treatment plans. Moving forward with determined steps rather than definite promises is the safest path in oncology.


References 

  • Hanahan D, Weinberg RA. (2011). Hallmarks of Cancer: The Next Generation. Cell. (Foundational work on the biological complexity of cancer).
  • Fisher B. (1980). Laboratory and clinical research in surgery. Cancer Research. (Biological determinism vs. probabilities).
  • National Comprehensive Cancer Network (NCCN) Guidelines. (2025). Patient and Professional Perspectives on Uncertainty.
  • Sledge GW Jr. (2016). Curing Cancer: Reality or Myth? Journal of Clinical Oncology.
  • Ioannidis JPA. (2005). Why most published research findings are false. PLoS Medicine. (Critical study on interpreting medical data).
  • Mayo Clinic. Understanding Cancer Prognosis: Statistics vs. Reality.
DROZDOGAN AI

Explore this article together

Ask about the article and read answers alongside published sources from our site.

DROZDOGAN AI

Drozdogan Assistant

Why Is There No Certainty in Cancer Treatment?

Ask about the article and read answers alongside published sources from our site.

Conversation and privacy information

Drozdogan Assistant answers this conversation. Authorized site administrators may review it for quality. Do not share personal information.

Replies use OpenAI infrastructure. Questions and replies are processed by that service; conversation records are stored on our site. Do not share identifying, contact or personal health information.

0 / 1000

For information only; no personal diagnosis or treatment advice.

Related articles

Explore other articles on this topic.

Stay informed

Receive new articles and scientific updates by email.

Google Analytics runs on public pages independently of this window and may use analytics cookies. Your choice here controls external services only.

Cookie policy