10 Cancer Warning Signs Every Indian Should Know — Never Ignore These

In my years as a surgical oncologist in Coimbatore, one pattern repeats itself painfully often: a patient sits across from me with a cancer that could have been cured — if only they had come two years earlier.

The tragedy is that many of these patients noticed something wrong but waited. They assumed it would pass. They were afraid of what the answer might be. Or they simply did not know that what they were feeling was a warning sign.

This article is my attempt to change that.

Warning Sign 1: A Lump You Can Feel

Any new, unexplained lump — in the breast, neck, armpit, groin, or anywhere on the body — that does not disappear within 2–3 weeks must be investigated. Not all lumps are cancer. The vast majority are benign. But you cannot know without examination and appropriate investigation (ultrasound, biopsy).

Do not wait and watch a lump for months. If it is growing, hard, fixed to underlying tissue, or accompanied by skin changes — see a doctor urgently.

Warning Sign 2: Unexplained Weight Loss

Losing more than 5 kg in a few months without trying — without changing your diet or exercise — is a red flag. Many cancers cause weight loss, particularly cancers of the stomach, esophagus, pancreas, and lung. It happens because cancer cells consume nutrients and because cancers produce substances that suppress appetite and alter metabolism.

Warning Sign 3: Persistent Cough or Blood in Sputum

A cough lasting more than 3 weeks — particularly in a smoker or ex-smoker — needs investigation with a chest X-ray at minimum. Coughing up blood (haemoptysis), even in tiny amounts, should be investigated urgently. It does not always mean cancer — but it must be evaluated. Lung cancer, endobronchial tumours, and laryngeal cancers can all cause these symptoms.

Warning Sign 4: Difficulty Swallowing

Progressive difficulty swallowing — particularly with solid food that seems to get stuck — is one of the hallmarks of esophageal cancer or stomach cancer. It often starts subtly and patients adapt unconsciously by switching to softer foods. By the time swallowing is severely impaired, the cancer may be at an advanced stage. Any new or worsening swallowing difficulty in an adult over 40 must be investigated with an endoscopy.

Warning Sign 5: Blood in Stool, Urine, or Unusual Bleeding

• Blood in stool — even once — must not be dismissed as "just piles." Colorectal cancer and rectal cancer bleed. Colonoscopy is essential.
• Blood in urine (haematuria) — even without pain — can indicate kidney, bladder, or ureteral cancer.
• Post-menopausal vaginal bleeding — any bleeding after menopause must be investigated for endometrial or cervical cancer.
• Abnormal nipple discharge — particularly blood-stained — needs breast evaluation.

Warning Sign 6: A Sore or Ulcer That Does Not Heal

Any ulcer in the mouth, tongue, lip, or skin that does not heal within 3 weeks should be seen by a doctor. Oral cancer — driven by tobacco, gutka, and paan use — is extremely common in India. Early oral cancer has cure rates above 80%. Advanced oral cancer has cure rates below 30%. The difference is whether patients acted on a non-healing ulcer.

Warning Sign 7: Unexplained Fatigue

Extreme, persistent tiredness that does not improve with rest — particularly when combined with other symptoms — can be a sign of many cancers including leukaemia, lymphoma, and gastrointestinal cancers. On its own, fatigue has many benign causes. But fatigue that is new, severe, and persisting for weeks alongside other symptoms warrants investigation with blood tests and examination.

Warning Sign 8: Changes in Bowel Habits

A persistent change in bowel habits — diarrhoea, constipation, or alternating between the two — lasting more than 4 weeks without a clear cause should prompt investigation with colonoscopy. Colorectal cancer commonly alters bowel habits. A feeling that the bowel does not empty completely (tenesmus) is another important symptom to mention to your doctor.

Warning Sign 9: Persistent Hoarseness or Voice Change

A hoarse voice lasting more than 3 weeks — in a smoker, ex-smoker, or anyone — needs examination of the vocal cords with a laryngoscope. Laryngeal (voice box) cancer and thyroid cancer can both affect the voice. Hoarseness can also occur with lung cancers that press on the nerve supplying the vocal cord (recurrent laryngeal nerve palsy) — often indicating an advanced or centrally located tumour.

Warning Sign 10: A New or Changing Skin Lesion or Mole

Any mole or skin lesion that is growing, changing colour, developing irregular borders, bleeding, or itching must be evaluated by a doctor. Skin cancer — including melanoma — is highly curable when caught early and surgically removed. The ABCDE rule for moles to watch:

• A — Asymmetry: One half unlike the other
• B — Border: Irregular, ragged, or blurred edges
• C — Colour: Multiple shades or uneven distribution
• D — Diameter: Larger than 6 mm (the size of a pencil eraser)
• E — Evolving: Any change in size, shape, colour, or symptoms

What Should You Do If You Notice Any of These Signs?

Do not search the internet for 3 hours and catastrophise. And do not ignore it hoping it will go away. Do one simple thing: see a doctor.

Most of the time, these symptoms will have a benign explanation. But if they do not — if a cancer is found — catching it at that appointment rather than 6 months later could mean the difference between a cure and a much harder battle.