Colorectal Cancer

Chemotherapy

Purpose

Kills rapidly growing cancer cells throughout the body.

Common drugs

5-FU, Capecitabine, Oxaliplatin

Used for

Stage II–IV or post-surgery to prevent recurrence

Targeted Therapy

Purpose

Blocks growth-promoting molecules

Common drugs

Bevacizumab, Cetuximab

Used for

Advanced or metastatic cancers with specific mutations

Immunotherapy

Purpose

Activates immune system to fight cancer

Common drugs

Pembrolizumab, Nivolumab

Used for

MSI-H or dMMR colorectal cancers

External Beam Radiation Therapy (EBRT)

How it works

Aims radiation at the tumor from outside the body

Treatment duration

Usually 5 days/week for 5–6 weeks

Intraoperative Radiation Therapy (IORT)

How it works

One-time dose of radiation during surgery

Treatment duration

Single session

Polypectomy and Local Excision

What it does

Removal of polyps or early-stage tumors through a colonoscope

Used for

Very early colorectal cancers

Recovery

Few days to 1 week

Colectomy (Partial or Total)

What it is

Removal of part or all of the colon

Used for

Localized colon cancers

Recovery

4-6 weeks

Proctectomy

What it is

Surgical removal of the rectum

Used for

Rectal cancer

Recovery

4–8 weeks

Colostomy/Ileostomy

What it is

Creates an opening for waste removal

Used for

Advanced cases or after rectal surgery

Recovery

Ongoing care and adjustment

Combination Therapy

Goal

Shrink or control widespread cancer

What it is

Multiple chemo drugs or chemo + targeted/immunotherapy

Used for

Stage IV or recurrent cases

Palliative Care

Goal

Relieve symptoms like blockage or bleeding

Used For

Late-stage or non-curative settings

Most common colorectal cancer

type from glandular cells of colon or rectum.

Early-stage

mainly treated with surgical resection of tumor.

Adjuvant chemotherapy (FOLFOX, CAPEOX)

used in stage II high-risk and stage III to reduce recurrence.

Advanced stages

may receive systemic chemotherapy plus targeted therapies (anti-EGFR such as cetuximab, panitumumab) per RAS mutation status.

Immunotherapy (nivolumab, pembrolizumab)

used for microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR) tumors.

Treatment tailored to molecular profiling

for best outcomes.

Rare lymphoid malignancies

arising within colorectal tissues.

Chemotherapy regimens

like CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) are standard.

Anti-CD20 antibody

rituximab immunotherapy is often combined for B-cell lymphomas.

Surgery

considered in obstruction, perforation, or localized bulky disease cases.

Radiation therapy

may be applied selectively.

Prognosis depends on lymphoma

subtype, stage, and therapy response.

• Also called intramucosal carcinoma or carcinoma in situ.
• Cancer cells are confined to the innermost layer of the lining of the colon or rectum (mucosa).
• Non-invasive at this stage.
• Highly treatable with surgery; excellent prognosis.

• Cancer has grown into the submucosa (layer beneath the mucosa) or muscularis propria (muscle layer) of the colon or rectum.
• No spread to nearby lymph nodes or distant sites.
• Tumor size up to T2, node status N0, metastasis M0.
• Treatment is mainly focused on the surgical removal of the tumor.

• Tumor has penetrated through the muscularis propria into outer layers, but no spread to lymph nodes or distant organs.
• Tumor size classified as T3 or T4a.
• No regional lymph node metastasis, no distant metastasis (N0 M0).
• Requires surgery, with possible chemotherapy afterward depending on risk factors.

• Any size tumor (any T), with spread to 1-3 or more regional lymph nodes (N1 or N2).
• No distant metastasis (M0).
• Multimodal treatment, including surgery and chemotherapy, is standard.

• Cancer of any tumor size or regional lymph node status has spread to distant organs (M1).
• Common metastatic sites include liver, lungs, and peritoneum.
• Advanced stage: generally not curable; treatment focuses on systemic therapies to control disease and symptoms.