What is the first sign of rectal cancer?

The most common first sign is bleeding while passing stools — often bright red or mixed in with the stool. Other early signs include a persistent change in bowel habit, tenesmus (the feeling of incomplete emptying), pencil-thin stools, or unexplained anaemia. Because these symptoms also occur with piles and fissures, many patients are treated for benign conditions for months before rectal cancer is diagnosed — which is why persistent bleeding deserves a colonoscopy, not just a haemorrhoid cream.

Is rectal bleeding always cancer?

No — most rectal bleeding is caused by piles (haemorrhoids), anal fissures, or other benign conditions, especially in younger people. But rectal cancer cannot be ruled out without a proper examination, often including colonoscopy. The combination of bleeding with a change in bowel habit, weight loss, anaemia, or tenesmus is particularly concerning. Anyone with rectal bleeding that does not settle with simple treatment, or recurs, should have a colonoscopy.

Is rectal cancer curable?

Yes — rectal cancer is highly curable when caught early. Stage I disease has 5-year survival rates above 90%. Even locally advanced rectal cancer can often be cured with a combination of neoadjuvant chemoradiotherapy followed by surgery. Modern sphincter-preserving and robotic surgical techniques mean most patients today avoid a permanent stoma. Advanced disease is managed with chemotherapy, targeted therapy and immunotherapy where appropriate.

Who is at higher risk of rectal cancer?

Adults over 50, those with a family history of colorectal cancer or adenomatous polyps, individuals with Lynch syndrome or familial adenomatous polyposis, people with long-standing inflammatory bowel disease, smokers and heavy drinkers, and those with obesity, type 2 diabetes or low-fibre diets are at elevated risk. Rectal cancer is also rising in adults under 50, so age alone is no longer a reliable filter.

How can rectal cancer be prevented?

Rectal cancer is one of the most preventable cancers. Screening colonoscopy from age 50 (or earlier with a family history) can detect and remove pre-cancerous polyps before they ever become cancer. Lifestyle changes that help include eating a high-fibre diet rich in fruits, vegetables and whole grains, limiting red and processed meats, maintaining a healthy weight, staying physically active, stopping smoking and limiting alcohol.

Rectal Cancer — Symptoms, Types & Causes

Name: Rectal Cancer — Types, Symptoms & When to See a Specialist
Creator: Dr. Paila Gowri Naidu
Published: 2026-05-01

Written by Dr. Paila Gowri Naidu · Surgical Oncologist · MBBS, MS (General Surgery), M.Ch (Surgical Oncology), FMAS
Medically reviewed by Dr. Kirti Ranjan Mohanty · Radiation Oncologist · MBBS, MD (Radiation Oncology)
Last medically reviewed: May 2026

Understanding the Condition

What is Rectal Cancer?

Rectal cancer occurs when cells in the rectum — the last 15 centimetres of the large bowel that connects the colon to the anus — begin to grow uncontrollably and form a tumour. Most rectal cancers start as a small, harmless-looking growth (polyp) on the rectal lining and slowly turn cancerous over years. This long pre-cancerous window is precisely what makes rectal cancer one of the most preventable and detectable cancers when screening is used.

Rectal cancer is rising in incidence across India, with a particularly worrying trend in younger adults under 50 — many of whom are diagnosed late because their symptoms are dismissed as piles or routine indigestion. Diets low in fibre, high in processed foods and red meat, rising rates of obesity and diabetes, and decreasing physical activity are all contributing. The good news is that rectal cancer found early is one of the most curable cancers, and screening colonoscopy in those over 50 (or earlier with a family history) can detect and remove pre-cancerous polyps before they ever become cancer.

Types of Rectal Cancer

The Main Types of Rectal Cancer

Rectal cancers are classified by the cell type they arise from. The overwhelming majority are adenocarcinomas, with several rare subtypes that behave differently.

95% of cases

Rectal Adenocarcinoma

By far the most common type, accounting for over 95% of rectal cancers. It begins in the glandular cells of the rectal lining, almost always developing from a pre-existing polyp. Treatment usually combines surgery with neoadjuvant chemoradiotherapy for locally advanced disease.

Aggressive variant

Mucinous & Signet-Ring Cell Adenocarcinoma

Aggressive variants of rectal adenocarcinoma that tend to occur in younger patients and have a slightly worse prognosis. Treatment principles remain the same but require closer multidisciplinary attention.

Rare · slow-growing

Rectal Neuroendocrine Tumours (Carcinoid)

Rare, usually slow-growing tumours of the rectum that often present as small polyps. Many small rectal NETs can be cured with endoscopic resection alone.

Rare · targeted therapy

Gastrointestinal Stromal Tumour (Rectal GIST)

A rare type of rectal tumour arising from specialised cells in the rectal wall. Treated very differently from adenocarcinoma — usually with targeted therapy (imatinib) combined with surgery.

Rare · chemo-led

Rectal Lymphoma

A rare cancer that develops in the immune cells of the rectum. Requires medical oncology-led treatment with chemotherapy rather than surgery as the primary approach.

For detailed information on diagnosis, sphincter-preserving and robotic surgery, neoadjuvant chemoradiation and modern systemic therapy options, see our dedicated page on rectal cancer treatment in Hyderabad.

Signs & Symptoms

Common Signs & Symptoms of Rectal Cancer

Rectal cancer often produces symptoms that are easy to dismiss as piles, fissures or routine bowel issues. Watch for any of the following — especially if they last more than 3 weeks:

Bleeding while passing stools — bright red or dark blood in the stool, or blood mixed with the stool (not just on toilet paper).
A persistent change in bowel habit — new constipation, diarrhoea, or alternating between the two.
Tenesmus — a feeling of incomplete emptying after passing stools.
Pencil-thin stools — or a noticeable change in stool shape.
Unexplained iron-deficiency anaemia — often the first lab finding in older men or postmenopausal women.
Persistent pain or discomfort — in the lower abdomen or rectum.
Unexplained weight loss — loss of appetite, or persistent tiredness.
Mucus discharge from the rectum.

Any of these symptoms lasting more than 3 weeks deserves a colonoscopy — not just treatment for presumed piles.

Regional Context

Rectal Cancer in Telangana & Andhra Pradesh

Rectal cancer is rising steadily across Telangana and Andhra Pradesh, and a worrying share of new diagnoses are now in adults under 50 — many of whom were treated for piles or fissures for months before the cancer was recognised. Three regional drivers stand out: shifting diets (more refined carbohydrates, processed and packaged foods, red meat; less fibre and traditional millet-based grains), rapidly rising obesity and type 2 diabetes, and a deep-rooted social discomfort about discussing bowel symptoms, which causes people to delay seeing a doctor.

Anyone with rectal bleeding, a persistent change in bowel habit, or new pencil-thin stools should have a colonoscopy — irrespective of age — rather than continued treatment for presumed piles.

Causes & Risk Factors

Common Causes & Risk Factors

Rectal cancer typically develops slowly over years, often from a polyp. The main risk factors are:

Age above 50 — although incidence is rising in younger adults.
Family history — of colorectal cancer or adenomatous polyps.
Inherited syndromes — Lynch syndrome and familial adenomatous polyposis (FAP).
Personal history of polyps or IBD — colorectal polyps or inflammatory bowel disease (ulcerative colitis, Crohn's disease).
Diets high in red and processed meat — low in fibre.
Obesity and physical inactivity.
Type 2 diabetes.
Smoking and heavy alcohol use.
Previous radiation therapy — to the abdomen or pelvis.

When to Act

When to See a Rectal Cancer Specialist

Any of the following should prompt a colonoscopy and specialist review, regardless of age:

Rectal bleeding — that persists, recurs, or is mixed with the stool.
A new change in bowel habit — lasting more than 3 weeks.
Tenesmus — the feeling of needing to pass stool even after you just have.
Pencil-thin stools — or noticeably narrower stools.
Unexplained iron-deficiency anaemia — especially in men or postmenopausal women.
A family history of colorectal cancer or polyps — screening from age 40 or earlier may be appropriate.
Continued bleeding despite treatment for piles.

A short specialist consultation and the right diagnostic test — imaging, endoscopy, biopsy, or blood test as appropriate — is usually enough to confirm or rule out cancer. Early action is always easier than catching up later.

Expert Care at CION

Specialist Rectal Cancer Care at CION Cancer Clinics

Our NABH-accredited centres across Hyderabad deliver evidence-based rectal cancer care — from colonoscopy and MRI staging through to laparoscopic and robotic-assisted sphincter-preserving surgery, total mesorectal excision (TME), neoadjuvant chemoradiotherapy, modern systemic therapy and stoma care — guided by NCCN and ESMO protocols and reviewed for every patient by a multidisciplinary tumour board.

For a detailed walk-through of rectal cancer diagnosis, treatment options, costs, and our specialist team, see our dedicated page on rectal cancer treatment in Hyderabad.

Disclaimer: This page is intended for general informational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified oncologist for guidance specific to your medical condition. Content on this page is periodically reviewed and updated by CION's medical team in accordance with current clinical guidelines.

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