Cancer Biology: Class 12 Project File

Title Page

 Topic: Cancer Biology

 Submitted By: [Your Name]
 Class: 12
 Submitted To: [Teacher's Name]
 School Name: [School Name]
 Date: [Date]

Table of Contents

1. Introduction to Cancer
2. Types of Cancer
3. Causes of Cancer
4. Symptoms of Cancer
5. Diagnosis and Detection
6. Stages of Cancer
7. Treatment Methods
8. Prevention of Cancer
9. Case Study
10. Conclusion
11. References

1. Introduction to Cancer

Cancer is a group of diseases characterized by uncontrolled growth and spread of abnormal

cells. If the spread is not controlled, it can result in death. Cancer can affect any part of the
body and is one of the leading causes of mortality worldwide.

Key Features:

 Abnormal cell growth

 Potential to invade other tissues
 Formation of tumors (benign or malignant)

Definition of Cancer

Cancer is a collective term for diseases characterized by:

 Uncontrolled Growth: Cancer cells grow and divide abnormally without the usual
checks and balances.
  Spread of Abnormal Cells: These cells can invade nearby tissues and spread to other
parts of the body.

Key Features:

1. Abnormal Cell Growth: Cancer cells ignore normal growth signals and multiply
unchecked.
2. Potential to Invade Other Tissues: Cancer can infiltrate surrounding healthy tissues,
disrupting their function.
3. Tumor Formation: Cancer can lead to the formation of masses called tumors, which
may be benign (non-cancerous) or malignant (cancerous and capable of spreading).

2. Types of Cancer

Cancers are categorized based on the origin of the abnormal cells:

1. Carcinomas: Affect epithelial cells (e.g., lung, breast).

 Origin: Epithelial cells (the cells that cover the surface of organs and tissues).

 Examples: Lung cancer, breast cancer.

Most common type of cancer in humans.

2. Sarcomas: Originate in connective tissues (e.g., bone, muscle).

 Origin: Connective or supportive tissues, such as bones, muscles, cartilage, or fat.

 Examples: Osteosarcoma (bone cancer), liposarcoma (fat tissue cancer).

3. Leukemias: Affect blood-forming tissues (e.g., bone marrow).

 Origin: Blood-forming tissues, including bone marrow.

 Nature: Unlike most cancers, leukemias do not form solid tumors but affect blood
and bone marrow.

 Example: Acute myeloid leukemia (AML).

4. Lymphomas: Begin in lymphatic system.

 Origin: Cells of the lymphatic system, which is part of the immune system.
 Examples: Hodgkin lymphoma, Non-Hodgkin lymphoma.
 Nature: Characterized by abnormal growth of lymphocytes (a type of white blood
cell).

5. Gliomas: Found in the brain and spinal cord.

  Origin: Glial cells in the brain and spinal cord.
 Examples: Astrocytoma, glioblastoma.
 Nature: Found in the central nervous system.

3. Causes of Cancer

Cancer mainly results from genetic mutations that alter the normal regulation of cell growth
and division. These mutations may be due to a combination of the following factors:

1. Environmental Factors:
= External agents that contribute to mutations include:
# Radiation exposure : Ultraviolet rays from the sun or ionizing radiation.
# Carcinogenic chemicals : Substances like asbestos or chemicals in tobacco smoke.

2. Lifestyle Factors:
= Choices and habits that increase cancer risk:
# Tobacco use : Primary cause of lung and other cancers.
# Poor diet : Diets that are high in fat and low in fiber may contribute to some
cancers.
# Lack of physical activity : Linked to a higher risk of cancer.

3. Genetic Predisposition:
= Inherited factors that make one more susceptible:
# Family history : Cancer can be inherited.
# Inherited gene mutations : Faulty genes passed down from parents (such as BRCA1
and BRCA2 for breast cancer).

4. Biological Factors:
= Infections or other internal causes:
# Viral infections : Certain viruses, such as Human Papillomavirus (HPV) and Hepatitis B,
are known to trigger cancer in specific tissues.

4. Symptoms of Cancer

This section enumerates common warning signs that may point to cancer. Each symptom
represents a potential disruption in the body due to abnormal cell growth. Here's a
breakdown:
•Unexplained weight loss : Sudden and significant weight loss without changes in diet or
physical activity is often an early sign of many types of cancer, particularly in the digestive or
endocrine system.

•Persistent fatigue : Feeling continually tired, even after ample rest, can be a consequence of
cancer cells that use much of the body's energy or substances emitted by cancer that affect the
body's metabolism.

•Pain or lump in specific areas :

• Pain: Can occur when tumors push against nerves or other parts of the body.
 • Lump: A physical mass or swelling in tissues, often the first noticeable sign in cancers
like breast or testicular cancer.

•Changes in skin appearance :

• Darkening, yellowing, or redness of the skin.
• Unusual sores that do not heal.
• Moles or spots that change in size, shape, or color (a potential sign of skin cancer).

• Prolonged cough or difficulty breathing : Other common symptoms of lung and throat
cancer include chronic coughing or shortness of breath.

These symptoms can have multiple causes and are not cancer specific. However, persistent
occurrences are a cause for visit to the doctor so as to diagnose the right one at the right time.

1. Diagnosis and Detection

Early diagnosis heightens the chances of curing. Some of the
major diagnostic techniques are:

 Imaging Techniques: These diagnose by creating pictures of

the internal body to look for abnormalities:

X-rays: Useful for detecting dense masses or abnormalities in bones and organs.

CT scans: Provide detailed cross-sectional images for identifying tumors.

MRI (Magnetic Resonance Imaging): Uses magnetic fields to produce highly

detailed images of soft tissues.

 Biopsies: Examination of tissue samples.

 This involves taking a small tissue sample from the suspected area.

 The sample is analyzed under a microscope to confirm the presence of cancer

cells.

 Blood Tests:  Tumor markers are substances released by cancer cells that can be
detected in the blood.

 Examples include PSA (Prostate-Specific Antigen) for prostate cancer and CA-125
for ovarian cancer.

 Genetic Tests:  These identify specific mutations in genes that might indicate a
higher risk of developing certain types of cancer.

 They are particularly useful for individuals with a family history of cancer.
 Each method plays a vital role in pinpointing the location, type, and
stage of cancer, significantly improving treatment outcomes.

6. Stages of Cancer

The classification of cancer into stages helps describe the severity and spread of the
disease. Each stage provides crucial information for treatment planning and prognosis.
Here's what the stages represent:
1.Stage 0: Localized, precancerous stage
• Cancer cells are present but confined to the original site.
• No invasion into nearby tissues.
• Often referred to as carcinoma in situ (e.g., localized cervical cancer).

2. Stage I: The tumour is small, which is confined to its primary location.

• The small tumour has not disseminated to the lymph node and other parts of the
body.
• Chances of treatment are greater when the cancer is early stages

3. Stage II: The tumor size increases while it may have possibly reached the nearby
area
• The tumor has increased in size or has extended to regional lymph nodes.
• More advanced than Stage I, but still limited spread.

4. Stage III: Local spread is significant

• Cancer is spread thoroughly in the area that is originally present, it is typically to
the next lymph node or tissue.
• This type of cancer will require extreme treatment like surgery and chemotherapy.

5.Stage IV: The cancer spreads to distant organs

: The cancer has spread into distant organs, such as the lung, liver or brain.
Advanced or terminal, treatment focused on prolonging life and symptom
management.
This staging system is important for understanding the progression of cancer and
tailoring individualized treatment strategies.

7. Treatment Methods

This section describes the main ways of treating cancer. The treatment approach is
selected according to the type, location, and stage of the cancer. Here's what each
entails:

1. Surgery: • It is the removal of tumors by physical means.

• Usually applied in localized cancers where the tumor can be totally removed.
 2. Radiation Therapy: • High-energy rays are used to kill or reduce the size of cancer
cells.

• Directed at specific regions, causing less damage to the surrounding healthy tissues.

3. Chemotherapy: • Uses aggressive drugs that kill rapidly dividing cancerous cells.

• Administered in cancers that have spread or cannot be surgically removed.

4. Immunotherapy: • Involves enhancing or altering the body's immune system to

fight cancer.

• Checkpoint inhibitors and CAR T-cell therapy are examples.

5. Targeted Therapy: • Targets specific genes, proteins, or cellular mechanisms that

promote cancer growth.

• Generally less toxic to the normal cells than chemotherapy.

6. Hormonal Therapy: • Involves inhibiting or reducing the hormones which feed

some types of cancer, such as breast and prostate cancer.

• Commonly employed in hormone-sensitive cancers.

Each therapy can be used alone or together, according to the requirements of an

individual patient and nature of cancer.

1. Prevention of Cancer
The prevention section emphasizes steps to reduce the risk of
developing cancer. Here's a detailed explanation:

1. Lifestyle Changes:
Avoid tobacco: Smoking is the main cause of cancers like lung, mouth, and throat cancer.
Quitting tobacco reduces the risk of cancer by a lot.
Eat a balanced diet : A diet rich in fruits, vegetables, and whole grains, and low in processed
and red meats can reduce the risk of cancer.
Regular exercise: Physical activity maintains a healthy weight and general well-being, which
prevents cancers like breast and colon cancer.

2.Vaccination:
HPV vaccine: The Human Papillomavirus is a leading cause of cervical and other cancers,
and the vaccine helps protect against it.
Hepatitis B vaccine: This vaccine prevents Hepatitis B virus infection, which is a risk factor
for liver cancer.

3.Regular Screenings:
Mammograms: They help to detect breast cancer early when it is more easily treated.
Colonoscopies : Identifies precancerous or cancerous changes in the colon and rectum.
these measures focus on reducing exposure to known risk factors, boosting immunity against
cancer-causing infections, and identifying cancer early for better outcomes.
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9. Case Study

Case: Lung Cancer in Smokers

•\tBackground: • The patient is a 55-year-old male who has a history of 30 years of smoking.
• Smoking is the biggest risk factor for lung cancer because it brings in carcinogens into the
lungs after years.

•\tSymptoms: • These are the classic symptoms for late-stage lung cancer: a cough that
persists, chest pain, and weight loss.
• These occur when the tumor outgrows the regular functioning of the lungs.

• Diagnosis: • A chest X-ray showed a mass in the lung, which is a common initial diagnostic
tool for lung issues.
• A biopsy (removal of tissue for microscopic examination) confirmed the mass as Stage III
lung carcinoma, indicating significant local spread.

• Treatment: The patient underwent a combination of surgery, chemotherapy, and radiation

therapy:
Surgery: Removed as much of the tumor as possible.
Chemotherapy and Radiation: Targeted residual cancer cells and reduced tumor size.
Outcome: • The size of the tumor significantly reduced, so it was a positive response to
treatment.
• The patient needs follow-ups to monitor recurrence or complication.
This case emphasizes early detection of the disease, the significance of smoking as a cause of
lung cancer, and the effectiveness of combined treatments in managing advanced stages of
the disease.
_______________________________________

10. Conclusion

It has concluded briefly stating the multiple dimensions of cancer and that medical science
has advanced it to better diagnosis and cure.

Finally, it puts emphasis on creating awareness and preventive measures in order to reduce
the burden of this disease all over the world.

Key Points:

Complexity of Cancer:
Cancer is not a single disease, but a group of diseases, which have different causes,
behaviors, and treatments. Hence, there is a great demand for diversified approaches to its
management.

Medical Advancements

Advancements in technology and research have improved early detection, treatment

effectiveness, and survival rates.

Prevention and Awareness

Educating the masses about risk factors, preventive measures (healthy lifestyle choices and
vaccinations), and the importance of early detection is critical to combating the global burden
of cancer.

This conclusion puts together the overall theme of the document by restating the importance
of having a holistic approach to the war against cancer through science, awareness, and
preventive measures.

11. References

1. [Book/Website Name, Author, Year]

2. "Understanding Cancer Biology," [Author Name], [Year].
3. [Journal/Research Article Name, Author, Year].