Colorectal Cancer

Colorectal Cancer refers to cancer that starts in the colon or rectum, both parts of the large intestine, which is the final section of your digestive system.

Colon cancer starts in the colon (large bowel).

Rectal cancer starts in the rectum (the last few inches before the anus).

Together, they’re often grouped as “colorectal cancer” because they share many features.

Risk Factors

Colorectal cancer usually develops slowly over years. It often starts from noncancerous polyps that form on the inner wall of the colon or rectum. 

Some risk factors include:

Age

Most cases are in people over 50

Family history

Having close relatives with colorectal cancer increases risk

Personal history

If you've had polyps or colorectal cancer before

Genetics

Inherited syndromes like Lynch syndrome and FAP (familial adenomatous polyposis)

Inflammatory bowel diseases

Like Crohn's disease or ulcerative colitis

Diet

High consumption of red or processed meats

Lifestyle factors

Smoking, heavy alcohol use, lack of exercise, obesity

Symptoms

Gallbladder cancer often doesn’t cause symptoms in its early stages. When symptoms do appear, they may include:

Changes in bowel habits

(diarrhea, constipation, narrowing of stool)

Blood in the stool

Fatigue

Abdominal discomfort

Unexplained weight loss

Stages of Colorectal Cancer

The stage refers to how much the cancer has grown and spread:

Stage 0

Carcinoma in situ: Cancer is in the innermost lining only

Stage I

Cancer has grown into the next layer of tissue but hasn’t spread outside the colon/rectum

Stage II

Cancer has grown through the wall of the colon/rectum but hasn’t reached nearby lymph nodes

Stage III

Cancer has spread to nearby lymph nodes but not to other parts of the body

Stage IV

Cancer has spread (metastasized) to distant organs like the liver, lungs, or brain

Treatment Options

Treatment depends on the stage:

Surgery

Early stages: Remove the tumor and surrounding tissue. Sometimes remove part of the colon (colectomy).

Chemotherapy

Drugs that kill cancer cells, often used after surgery to kill leftover cells.

Radiation therapy

Mainly used for rectal cancer (before or after surgery).

Targeted therapy

Drugs that attack specific cancer cell features (like EGFR or VEGF inhibitors).

Immunotherapy

Helps your immune system recognize and fight cancer cells — usually used in advanced or genetic cases (like MSI-H cancers).

Survival Rates and Prognosis

Survival rates are often discussed in “5-year relative survival” terms:

Localized (stage I)

~91%

Regional (stage II or III)

~72%

Distant (stage IV)

~15%

(These are averages; survival can vary a lot depending on specific factors.)
Key point: Early detection massively boosts survival chances.

Genetics and Colorectal Cancer

Some people inherit mutations that make them much more likely to get colorectal cancer

  • Lynch Syndrome: High lifetime risk (up to 80%)
  • FAP (Familial Adenomatous Polyposis): Hundreds to thousands of polyps develop in the teen years — almost guaranteed cancer without treatment.

Genetic testing is recommended if family history is strong or if cancer appears very young (before 50).

Prevention and Screening

Best ways to reduce risk:

  • Colonoscopy starting at age 45 (sometimes earlier if at high risk)
  • Remove polyps before they turn into cancer
  • Eat a healthy diet (lots of fruits, veggies, fiber)
  • Exercise regularly
  • Quit smoking and limit alcohol
  • Maintain a healthy weight

Other screening options: stool tests, sigmoidoscopy, CT colonography

Colon and Rectal Diseases

Piles

Hemorrhoids (also called piles) are swollen veins in the lower part of your rectum or anus, similar to varicose veins. They can develop inside the rectum (internal hemorrhoids) or under the skin around the anus (external hemorrhoids).

Causes

  • Straining during bowel movements
  • Sitting for long periods, especially on the toilet
  • Chronic constipation or diarrhea
  • Low-fiber diet
  • Pregnancy (pressure from the uterus)
  • Aging (tissues get weaker)
  • Heavy lifting regularly

Symptoms

  • Pain or discomfort
  • Itching or irritation
  • Swelling around the anus
  • Bleeding during bowel movements (bright red blood)
  • A lump near your anus, which might be sensitive or painful

Treatment options

  • Home care: high-fiber diet, staying hydrated, warm sitz baths, over-the-counter creams
  • Medical procedures: rubber band ligation, sclerotherapy, infrared coagulation, or surgical removal in severe cases

Anal Fistula

An anal fistula is an abnormal tunnel that forms between the inside of the anus or rectum and the skin around the anus. It’s often the result of an infection in an anal gland that leads to an abscess (a collection of pus), and when the abscess drains, a fistula can develop.

Causes

Often from anal abscesses, but also linked to conditions like Crohn’s disease, tuberculosis, cancer, or trauma.

Symptoms

  • Pain and swelling around the anus
  • Discharge of pus or blood
  • Skin irritation
  • Sometimes fever if an infection is present

Diagnosis

Usually by physical examination, sometimes imaging like MRI or endoanal ultrasound is needed.

Treatment options

  • Surgery is almost always needed to cure a fistula.
    Options include fistulotomy (opening the fistula tract), seton placement (a thread placed to allow drainage and healing), or more complex surgeries like LIFT procedure or advancement flaps.
  • Antibiotics might help with infections but don't usually cure a fistula alone.

Anal Fissure

An anal fissure is a small tear or cut in the thin, moist tissue (mucosa) lining the anus. It can cause pain and bleeding during and after bowel movements.

Causes

  • Passing large or hard stools
  • Chronic constipation or diarrhoea
  • Straining during bowel movements
  • Childbirth
  • Sometimes unknown (idiopathic)

Symptoms

  • Sharp pain during bowel movements
  • Bright red blood on toilet paper or in the toilet
  • Visible tear or crack near the anus
  • Itching or irritation around the anus

Treatment options

  • Conservative: Increasing fiber and water intake, taking stool softeners, sitz baths (warm water soaks), applying topical anesthetics or vasodilators (like nitroglycerin ointment).
  • Medical: If it doesn’t heal, treatments like Botox injections or surgery (lateral internal sphincterotomy) may be needed to relax the muscle and promote healing.

Most acute fissures (new ones) heal with simple measures, but chronic fissures (lasting over 6 weeks) might need more intensive treatment.

Pilonidal sinus

A pilonidal sinus is a small tunnel or tract that forms under the skin, usually near the top of the buttocks where they separate (the natal cleft). It often contains hair, debris, and skin. If it gets infected, it can become a painful abscess (collection of pus) and cause swelling, redness, and drainage.

Causes

It’s usually thought to be due to loose hairs penetrating the skin and causing an inflammatory reaction. Sitting a lot, friction, and excessive hair make it more likely.

Symptoms

  • Pain, swelling, redness
  • Discharge of pus or blood
  • Sometimes a foul smell

Prevention

  • Good hygiene
  • Hair removal (sometimes shaving or laser hair removal)
  • Avoiding prolonged sitting

Treatment options

  • If infected: Antibiotics and often surgical drainage
  • Chronic cases: Surgery to remove the sinus tract and prevent future infections.

The main goal is to remove the sinus tract and prevent it from coming back. Here are the common types of surgeries:

Incision and Drainage (I&D)
  • When used: If there is an active infection with an abscess.
  • What happens: A small cut is made to drain out pus.
  • Note: This is only temporary — the sinus usually needs full surgery later.
Excision and Healing by Secondary Intention
  • When used: For chronic or recurring pilonidal sinus.
  • What happens: The whole sinus and any tracts are cut out. The wound is left open to heal naturally from the inside out.
  • Pros: Lower risk of infection.
  • Cons: Healing can take weeks and requires daily dressing changes.
Excision and Primary Closure
  • What happens: After removing the sinus, the edges of the skin are stitched closed immediately.
  • Pros: Faster healing.
  • Cons: Higher risk of recurrence or wound infection if not properly cared for.
Flap Surgery (e.g., Limberg Flap, Karydakis Procedure)
  • When used: For complex or multiple sinuses.
  • What happens: After excision, nearby skin and tissue are moved ("flapped") to cover the area.
  • Pros: Lower chance of recurrence, better cosmetic results.
  • Cons: More complex surgery.

Aftercare is super important!

  • Keep the area clean and dry.
  • Sometimes hair removal is recommended after surgery.
  • Avoid sitting for long periods during recovery.