Cancer Overview: Types, Causes, and Treatments
Know about cancer, what it is, types, causes, symptoms, treatment options, diagnosis and tips for caregivers and more.
Written by Dr. M L Ezhilarasan
Reviewed by Dr. Rohinipriyanka Pondugula MBBS
Last updated on 29th Aug, 2025
Introduction
Cancer is a word that can bring fear and uncertainty, but understanding it better can help you feel more in control. Whether you or a loved one is affected, knowing the basics—types, causes, and treatment options can make a big difference.
This article will guide you through what cancer is, how it develops, and the ways it can be managed or treated.
What Is Cancer?
Cancer is a disease where some of the body’s cells grow uncontrollably and spread to other parts of the body. Normally, cells grow, divide, and die in an orderly way. But in cancer, this process breaks down cells keep multiplying when they shouldn’t, forming lumps called tumours (in most cases).
Not all tumours are cancerous. Benign tumours do not spread and are usually harmless, while malignant tumours are cancerous and can invade nearby tissues or travel to other parts of the body (metastasis).
Consult an Oncologist for Personalised Advice
Common Types of Cancer
There are more than 100 types of cancer, but some of the most common ones include:
1. Breast Cancer – Affects breast tissue, mostly in women but can also occur in men.
2. Lung Cancer – Often linked to smoking but can also occur in non-smokers.
3. Prostate Cancer – Affects the prostate gland in men.
4. Colorectal Cancer – Affects the colon or rectum.
5. Skin Cancer – Includes melanoma, basal cell carcinoma, and squamous cell carcinoma.
6. Leukaemia – A blood cancer affecting white blood cells.
7. Lymphoma – Affects the lymphatic system (Hodgkin’s and non-Hodgkin’s lymphoma).
Each type behaves differently, so treatments vary based on where the cancer starts and how it progresses.
What Causes Cancer?
Cancer develops due to changes (mutations) in DNA that control cell growth. These mutations can be inherited or caused by external factors, including:
1. Lifestyle Factors
- Tobacco Use – Smoking or chewing tobacco is linked to lung, mouth, throat, and bladder cancers.
- Poor Diet – High consumption of processed foods, red meat, and low fibre intake may increase risk.
- Lack of Exercise – Physical inactivity is linked to higher cancer risks.
- Alcohol – Excessive drinking increases the risk of liver, breast, and oesophageal cancers.
2. Environmental Factors
- Radiation – UV rays from the sun or tanning beds can cause skin cancer.
- Chemical Exposure – Asbestos, benzene, and certain pesticides are linked to cancer.
- Air Pollution – Long-term exposure may increase lung cancer risk.
3. Infections
Some viruses and bacteria increase cancer risk, such as:
- HPV (Human Papillomavirus) – Linked to cervical and throat cancers.
- Hepatitis B & C – Can lead to liver cancer.
- H. Pylori – A stomach bacterium that may cause stomach cancer.
4. Genetic Factors
- Some people inherit gene mutations (like BRCA1 and BRCA2) that increase their risk of breast, ovarian, and other cancers.
Common Symptoms of Cancer
Symptoms vary depending on the type and stage of cancer, but some general warning signs include:
- Unexplained weight loss
- Persistent fatigue
- Lumps or swelling
- Changes in bowel or bladder habits
- Unusual bleeding or discharge
- Persistent cough or hoarseness
- Difficulty swallowing
- Skin changes (new moles, sores that don’t heal)
Note: These symptoms can also be caused by non-cancerous conditions, but if they persist, it’s best to see a doctor.
How Is Cancer Diagnosed?
If cancer is suspected, doctors may recommend:
- Imaging Tests (X-rays, CT scans, MRIs) – To locate tumours.
- Biopsy – Removing a small tissue sample to check for cancer cells.
- Blood Tests – Some cancers release markers detectable in blood.
- Endoscopy – A thin tube with a camera examines internal organs.
Early detection improves treatment success, so regular screenings (like mammograms, Pap tests, and colonoscopies) are crucial for at-risk individuals.
Cancer Treatment Options
Treatment depends on the type, stage, and overall health of the patient. Common options include:
1. Surgery
Removes the tumour and nearby affected tissue. Often used for solid tumours.
2. Chemotherapy
Uses strong drugs to kill cancer cells or stop their growth. Can have side effects like hair loss and fatigue.
3. Radiation Therapy
High-energy rays target and destroy cancer cells. Often used alongside surgery or chemo.
4. Immunotherapy
Boosts the immune system to fight cancer. Works well for some advanced cancers.
5. Targeted Therapy
Drugs attack specific cancer cell weaknesses without harming normal cells.
6. Hormone Therapy
Blocks hormones that fuel certain cancers (like breast and prostate cancer).
7. Stem Cell Transplant
Replaces damaged bone marrow with healthy stem cells (used in leukaemia and lymphoma).
Living with Cancer: Tips for Patients & Caregivers
A cancer diagnosis can be overwhelming, but these steps can help manage the journey:
For Patients:
- Follow Treatment Plans – Stick to doctor-recommended therapies.
- Eat a Balanced Diet – Focus on fruits, vegetables, lean proteins, and whole grains.
- Stay Active – Light exercise (as permitted) can boost energy and mood.
- Manage Stress – Meditation, yoga, or counselling can help.
- Join Support Groups – Connecting with others facing similar challenges can be comforting.
For Caregivers:
- Educate Yourself – Learn about the type of cancer and treatment side effects.
- Offer Emotional Support – Listen and be patient.
- Help with Daily Tasks – Assist with meals, medications, or doctor visits.
- Take Care of Yourself – Caregivers need rest and support too.
Can Cancer Be Prevented?
While not all cancers are preventable, you can lower your risk by:
- Avoiding tobacco and excessive alcohol
- Eating a healthy diet rich in fruits and vegetables
- Staying physically active
- Protecting skin from excessive sun exposure
- Getting vaccinated (e.g., HPV, Hepatitis B)
- Regular screenings for early detection
When to See a Doctor?
If you notice persistent symptoms or have a family history of cancer, consult a doctor. Early detection saves lives.
Final Thoughts
Cancer is a complex disease, but advances in medicine have improved survival rates significantly. Staying informed, getting regular check-ups, and adopting a healthy lifestyle can make a big difference. If you or someone you know is affected, remember—you’re not alone, and support is available.
Consult an Oncologist for Personalised Advice
Consult an Oncologist for Personalised Advice
Dr. Rupam Manna
Radiation Specialist Oncologist
4 Years • MBBS MD(RADIO THERAPY)
Barasat
Diab-Eat-Ease, Barasat
Dr Gowshikk Rajkumar
Oncologist
10 Years • MBBS, DMRT, DNB in Radiation oncology
Bengaluru
Apollo Clinic, JP nagar, Bengaluru
Dr Sunita Samleti
Oncologist
18 Years • M.D. (Pathology)- TN Medical College, Mumbai University, Mumbai, Mar 2005 M.B.B.S. Grant Medical College, Mumbai University, Mumbai, Oct 1999
Chinagadila
Apollo Hospitals Health City Unit, Chinagadila
Dr.sanchayan Mandal
Oncologist
17 Years • MBBS, DrNB( MEDICAL ONCOLOGY), DNB (RADIOTHERAPY),ECMO. PDCR. ASCO
Kolkata
Dr. Sanchayan Mandal Oncology Clinic, Kolkata
Dr. Sanchayan Mandal
Oncologist
17 Years • MBBS, DNB Raditherapy, DrNB Medical Oncology
East Midnapore
VIVEKANANDA SEBA SADAN, East Midnapore
Consult an Oncologist for Personalised Advice
Dr. Rupam Manna
Radiation Specialist Oncologist
4 Years • MBBS MD(RADIO THERAPY)
Barasat
Diab-Eat-Ease, Barasat
Dr Gowshikk Rajkumar
Oncologist
10 Years • MBBS, DMRT, DNB in Radiation oncology
Bengaluru
Apollo Clinic, JP nagar, Bengaluru
Dr Sunita Samleti
Oncologist
18 Years • M.D. (Pathology)- TN Medical College, Mumbai University, Mumbai, Mar 2005 M.B.B.S. Grant Medical College, Mumbai University, Mumbai, Oct 1999
Chinagadila
Apollo Hospitals Health City Unit, Chinagadila
Dr.sanchayan Mandal
Oncologist
17 Years • MBBS, DrNB( MEDICAL ONCOLOGY), DNB (RADIOTHERAPY),ECMO. PDCR. ASCO
Kolkata
Dr. Sanchayan Mandal Oncology Clinic, Kolkata
Dr. Sanchayan Mandal
Oncologist
17 Years • MBBS, DNB Raditherapy, DrNB Medical Oncology
East Midnapore
VIVEKANANDA SEBA SADAN, East Midnapore
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