Cancer – Overview, Symptoms, and Types

Cancer is a common disease caused by changes in DNA. Cancer begins when the cells divide without control and spread into nearby tissues. Most of the cancer-causing DNA changes happen on the portions of DNA called genes.

Cancer Symptoms

The signs and symptoms of cancer could vary based on the cancer type. But here are the common symptoms related to cancer:

• Lump felt below the skin
• Unintended weight loss or gain
• Changes in existing moles
• Skin may change in the yellow or red colour, or darkening of the skin might occur
• Sores that do not heal
• Fatigue
• Changes in bowel habits
• Continuous coughing or trouble breathing
• Regular discomfort after eating
• Continuous muscle or joint pain
• Bleeding or bruising due to an unknown cause
• Unexplained continuous fevers or night sweats
• Changes in bladder habits
• Hardness in swallowing
• Hoarseness
• Continuous indigestion

Cancer Types

Cancer is classified into two types. They are:

1) Solid tumour cancers

It can occur in any part, even in common places, including the breast, colon, prostate, and lung.

2) Hematologic (blood) cancers

Hematologic cancer is also called blood cancer. Lymphoma, multiple myeloma, and leukaemia are types of blood cancer. They usually start in the cells of the immune system or in blood-forming tissue, like bone marrow.

The causes and risk factors for cancer might vary based on the cancer type and the cancer patient.

Various types of cancer are given below:

1) Bladder cancer

When the bladder cells start to grow abnormally, bladder cancer starts building a tumour in the bladder. This cancer, which mostly affects older adults, is diagnosed earlier when it is a treatable condition. Bladder cancer’s general symptom is the blood in the urine. Surgery, biological therapy, and chemotherapy are the main treatments.

2) Breast cancer

Breast cancer starts with the growth of cells in the breast tissue. This cancer occurs in women generally and rarely in men. A pain in the breast, a lump in the breast, a lump in the armpit, blood coming from the nipple, or changes in the shape or texture of the breast, nipple, or skin over the breast are the symptoms of breast cancer. Its treatment depends on the stage of cancer. Treatment includes chemotherapy, hormone therapy, radiation, and surgery in a combined multimodality type.

3) Colorectal cancer

Colon cancer grows from polyps (growths) in the inner lining of your colon. The symptoms of this cancer vary depending on the size and location of the cancer. Colorectal cancer symptoms include changes in stool consistency, changes in bowel habits, abdominal discomfort, and blood in the stool.

Its treatment also depends on the size, location, and distance at which the cancer has spread. Surgery, radiation therapy, and chemotherapy, are the major treatments for colorectal cancer. If this cancer is left untreated, it might spread to other areas of your body.

4) Kidney cancer

Kidney cancer is a cancer that initiates in the bean-shaped organ kidney.

Renal cell carcinoma (RCC):

The renal cell carcinoma type of cancer develops in the cells that line your kidney’s tubules. This cancer usually affects adults and accounts for 85% of all kidney cancers. Renal cell carcinoma might build up as a single tumour in one kidney, but it could affect both kidneys. 

Transitional cell cancer:

Transitional cell carcinoma starts in the renal pelvis. The renal pelvis is the area in which your ureter joins the main part of your kidney. Transitional cell carcinoma could happen in your ureters or bladder. Transitional cell cancer is the reason for 6% to 7% of all kidney cancers.

Renal sarcoma:

This is the very least common form of kidney cancer, but it accounts for nearly 1% of kidney cancer cases. Renal sarcoma starts in the kidney’s connective tissues and, if not treated, can affect the nearby organs and bones.

Wilms tumour:

Wilms tumour is a type of kidney cancer that, in general, affects children. This cancer accounts for nearly 5% of kidney cancers. Blood in the urine, pain in the side or back, lumps in the back or side, ankles and legs, Swelling, high BP, anaemia, fatigue, and loss of appetite are the main symptoms of kidney cancer.

Surgery (like partial nephrectomy and radical nephrectomy), ablation (cryoablation and radiofrequency ablation), radiation therapy, targeted drug therapy, immunotherapy, and chemotherapy are the main treatments for kidney cancer.

5) Non-Small Cell Lung Cancer (NSCLC)

Except for small-cell lung cancer (SCLC), all other types of epithelial lung cancer are non-small-cell lung cancer (NSCLC). Squamous cell carcinoma, adenocarcinoma, and large cell carcinoma are the common types of NSCLC, which can happen in uncommon histological variants. This lung cancer type affects smokers and non-smokers. Non-small cell lung cancer is usually similar to squamous cell carcinoma and adenocarcinoma in its behaviour. The symptoms include a continuous cough, coughing up blood, shortness of breath, and weight loss. Surgery, chemotherapy, and radiation are the common treatments for non-small cell lung cancer (NSCLC).

6) Non-Hodgkin Lymphoma

Non-Hodgkin lymphoma is the growth of malignant (cancer) cells in the lymph system, which is a part of the immune system. The lymph system, in general, helps protect the body from infections and diseases. Cancer starts in the lymphatic system when the body generates many abnormal lymphocytes, which are a type of white blood cell. Swollen lymph nodes, fever, night sweats, weight loss, stomach ache, chest pain, and loss of appetite are the Non-Hodgkin lymphoma symptoms. Immunotherapy, chemotherapy, targeted therapy, stem-cell transplant, radiation therapy, or medication are the symptoms of non-Hodgkin lymphoma.

7) Melanoma

Melanoma is a skin cancer type that starts in the melanocytes. Melanocytes are cells that generate the pigment melanin, which gives skin its colour.  To put it simply, melanoma happens when the pigment-generating cells that provide colour to the skin turn cancerous. 

An uncommon growth or a change in the already-formed mole might be the symptom of melanoma, which could occur anywhere on the body. Surgery, radiation, medication, or chemotherapy are the most common treatments for melanoma.

8) Oral and Oropharyngeal Cancer

Oral cancer (mouth cancer) is the general form of head and neck cancer, which starts in any region of the mouth, like the tongue. Mostly, this cancer affects people aged 60 and older. Oral cancer generally affects your lips and tongue, especially the mouth roof and mouth floor. Oropharyngeal cancer is a cancer that starts and affects the oropharynx. A region of the throat (pharynx) just behind the mouth is the oropharynx.

Tobacco use, human papillomavirus (HPV) infection, heavy alcohol use, and genetic factors are the risk factors for oral cancer. A sore that does not heal, a lump, or a white or red patch on the mouth’s inside are the symptoms of oral cancer. Surgery, radiation therapy, and sometimes chemotherapy are the treatments for oral cancer.

9) Pancreatic Cancer

Pancreatic cancer is a cancer type that develops in the pancreatic tissues. Smoking and health history are the risk factors for pancreatic cancer. Jaundice, pain, and weight loss are the symptoms of pancreatic cancer. It’s difficult to diagnose pancreatic cancer. It usually starts in the organ that lies behind the stomach’s lower part (the pancreas).

Pancreatic secretion helps with digestion and the regulation of sugar metabolism. This cancer is often diagnosed late, grows rapidly, and has a poor prognosis.

No symptoms will be found in the early stages of pancreatic cancer. But its later stages show symptoms, but these could not be specific, like lack of appetite and weight loss. Surgery in the pancreas, radiation, and chemotherapy are the treatments for this type of cancer.

10) Prostate cancer

Prostate cancer is cancer that happens in the prostate in males. A man’s prostate functions to generate the seminal fluid that nourishes and transports sperm. Symptoms of prostate cancer might include hardness with urination, but there are no symptoms in some cases.

A few types of prostate cancer grow very slowly. In a few cases, proper monitoring is recommended. Radiation, hormone therapy, surgery, chemotherapy, or other treatments are needed for this type of cancer.

11) Thyroid Cancer

Thyroid cancer refers to the growth of cancerous cells in the thyroid gland tissues. There are various types of thyroid cancer. Age, gender, and exposure to radiation are risk factors for thyroid cancer. A combination of genetic and environmental factors could be the cause of thyroid cancer. While some people don’t get symptoms, others might see a lump in the neck. Surgery, radioactive iodine, radiation, hormone therapy, chemotherapy, and targeted therapies are the treatments for thyroid cancer.

12) Uterine Cancer

Uterine cancer is divided into two types, namely endometrial cancer (more common) and uterine sarcoma (rare). Uterine cancer mostly starts in the cell layers that build the lining (endometrium) of the uterus. The risk factors for uterine cancer are being overweight, having periods at an early age, and delaying menopause. Vaginal bleeding after menopause and bleeding between periods are the symptoms of this cancer type. For women with uterine cancer, surgery is the main treatment. Advanced cases might require therapy, chemotherapy, or radiation.

Cancer Causes

Genetic mutation is the main cause of cancer. Several forces can cause gene mutations. Factors like smoking, cancer-causing chemicals (carcinogens), viruses, obesity, hormones, radiation, chronic inflammation, and a lack of exercise are the causes of genetic mutation.

It might also be caused by a combination of factors, like genetics and a person’s environment. Cancer might start when the cells either reject or do not get the signal to end the growth or die. Instead, these cells continue to multiply and grow into visible tumours. Similar to the other organs in the human body, tumours also require nutrients and a regular blood supply to exist. As they become bigger, they generate the signals for angiogenesis, which is the progress of new blood vessels.

Cancer Treatment

Cancer treatment includes the following methods:

1) Surgery

A surgery or operation involved in cancer treatment includes cutting out tissues with cancer cells by professional doctors.

2) Radiation therapy

Radiation therapy is a method that uses high-energy rays (similar to X-rays) to remove cancer cells.

3) Chemotherapy

The cancerous cells will either shrink or be killed through the special medicines in this method.

4) Hormone therapy

Hormone therapy involves techniques that stop cancer cells from getting the hormones they need for their growth.

5) Immunotherapy

Immunotherapy helps your body’s immune system fight against cancer cells or regulate the side effects of other cancer treatments.

6) Stem cell transplant

It is otherwise called a bone-marrow transplant. It helps to replace the lost bone marrow cells because of the high doses of radiation therapy or chemotherapy. This stem cell transplant is mostly used for treating blood cancers, which begin in the lymph nodes.

Cancer Diagnosis

The diagnostic procedures for cancer might involve some diagnostic methods like imaging, laboratory tests, etc. The different cancer diagnosis methods include:

• Diagnostic imaging
• Lab tests
• Endoscopic exams
• Genetic tests
• Tumour biopsies
• Surgery

Clinical chemistry involves some chemical methods to note down the levels of chemical components in body fluids and tissues. Blood and urine are the most commonly used specimens in clinical chemistry.

Some of the more common laboratory tests are given below:

• Complete blood count (CBC)
• Blood tests
• Urinalysis
• Tumour markers

When do I see a doctor?

If you see any of the continuous signs or symptoms of cancer that are visible to you, then consult your doctor and make an appointment. If you don’t see any signs or symptoms of cancer but you worry about the risk of cancer, then discuss it with your doctor to seek advice. You could also inquire about which cancer screening tests and procedures are suitable for you.

Cancer Prevention

The factors that cause cancer are the key points to be considered in one’s lifestyle to reduce their cancer risk. Here are some of the preventive measures that could help reduce your cancer risk:

• Avoid smoking, which could affect you and even others. Also, avoid the secondhand smoke.
• Do not chew or consume tobacco.
• Restrict eating processed meats.
• Eat a healthy diet, which mainly concentrates on plant-based foods, healthy fats, and lean proteins.
• Quit drinking alcohol or drink in moderation.
• Maintain a correct body weight and BMI.
• Do moderate physical activity for 150 to 300 minutes per week regularly.
• Be away from the sun by avoiding direct sun exposure by wearing a hat, broad-spectrum sunscreen, and sunglasses. However, note that optimal vitamin D synthesis through sun exposure (avoid longer-term sun exposure) between 10 a.m. and 1 p.m. is necessary.
• Do not tan beds. Indoor tanning equipment (e.g., beds and lamps) generates ultraviolet (UV) radiation, which might stimulate the skin to generate a pigment called melanin. Melanin absorbs UV radiation and causes the skin to darken.
• Vaccinate against viral infections that could result in cancer, like hepatitis B and HPV. 
• Consult your doctor regularly so they can diagnose the type of cancer if you find any symptoms. This might help you find out about any possible cancers very soon.

Conclusion

Cancer is a common disease that might occur suddenly because of genetic variations. There are many types of cancer that could occur in different parts of the body. Some cancers show visible symptoms, while others have developed symptoms lately.

Several treatments, like surgery, chemotherapy, radiation therapy, etc., help treat cancer. However, one could follow medicines along with the proper treatment if cancer is diagnosed. To prevent cancer, you could regularly include cancer-reducing foods in your diet. 

FAQs