Dr. Nandish Kumar Jeevangi, Sr. Consultant, Medical Oncology, HCG Cancer Center – Gulbarga

In the current scenario, Lung cancer is shedding its smoker’s disease label, as more number
of non-smokers are being diagnosed, challenging the traditional assumptions about the
disease’s causes and forcing a rethink among the medical professionals and the public alike.
A silent transformation
Lung cancer is increasingly affecting non-smokers, with one in five cases globally occurring
among the non-smokers. The trend is particularly striking among the younger adults and
women, highlighting the growing impact of environmental, lifestyle and genetic factors on
cancer risk.
The question is no longer limited to “Do you smoke?” but rather, “What are you exposed to
every day?”
Breathing in Danger: Air Pollution’s role
In cities across the world, simply stepping outside has become a health risk. Urban air is
thick with microscopic pollutants – PM2.5 particles, vehicle emissions, industrial smoke, and
construction dust, all of which can lodge deep inside the lungs. Over time, these particles
cause chronic inflammation and DNA damage, laying the groundwork for cancerous growth.
Studies show that long-term exposure to polluted air can carry nearly the same risk as light
smoking. The irony is stark: even those who consciously avoid cigarettes may unknowingly
inhale the equivalent of several a day just by breathing polluted air.
The hidden hazards within homes
While outdoor pollution grabs headlines, indoor air can often be worse. Poorly ventilated
kitchens, especially those using biomass fuels or cooking on high flames, release toxic fumes
and fine particles that accumulate over years. Radon gas, a naturally occurring radioactive
gas that seeps through floors and walls, is another invisible culprit linked to lung cancer in
non-smokers. Even small lifestyle choices, like burning incense sticks, candles, or using
aerosol-based cleaning products, can introduce carcinogens into enclosed spaces. We tend
to view our homes as safe havens, but for many, prolonged indoor exposure becomes a
slow and silent health hazard.
Genetic links and Molecular Triggers
Not all cases stem from the environment. Researchers have found specific gene mutations –
such as EGFR, ALK, and ROS1 – that are more common among non-smokers, particularly
women. These mutations cause cells in the lungs to multiply uncontrollably, leading to
cancer even without external triggers. This discovery has revolutionized treatment
approaches. Patients with these mutations often respond better to targeted therapies –
precision medicines designed to attack only cancerous cells – offering improved outcomes
and fewer side effects compared to traditional chemotherapy.
Occupational and Lifestyle Exposures

Workplace environments can also contribute to the rising trend. Prolonged exposure to
asbestos, diesel exhaust, arsenic, or other industrial chemicals significantly raises lung
cancer risk. Even low levels of second-hand smoke – inhaled passively over years in homes or
offices – remain harmful. Modern lifestyles add their own layer of risk. Sedentary habits,
processed diets, and chronic respiratory infections can weaken lung health, making the body
more vulnerable to environmental damage.
Breaking the Stigma
One of the biggest hurdles for non-smoking patients is stigma. The moment someone hears
“lung cancer,” the assumption often follows that the person must have smoked. This
misplaced judgment not only affects patients emotionally but can also delay diagnosis, as
many non-smokers dismiss persistent coughs or breathlessness, believing cancer couldn’t
happen to them. The narrative must change: lung cancer is not a smoker’s disease anymore

• it’s a societal disease shaped by the world we live in.
  Recognising early warning signs
  Lung cancer detected early can often be treated successfully, yet non-smokers rarely see
  themselves at risk. Common symptoms like a long-standing cough, chest pain, fatigue,
  hoarseness, or unexplained weight loss are frequently mistaken for minor infections.
  Regular health checks and low-dose CT scans for people with high environmental exposure
  or family history can help detect lung changes before they become life-threatening.
  Awareness and vigilance are the first lines of defence.
  Prevention starts with Awareness
  Addressing this rise requires collective action. Cleaner urban planning, strict air quality
  regulations, and better home ventilation can all make a measurable difference. On an
  individual level, ensuring proper airflow while cooking, reducing use of synthetic sprays,
  maintaining indoor plants, and wearing protective masks in polluted areas are simple but
  effective steps. Good lung health also depends on lifestyle choices – staying active, eating
  antioxidant-rich foods, and avoiding prolonged exposure to smoke or fumes.
  A Reality we can’t Ignore
  The rise in lung cancer among non-smokers is a stark reflection of how modern life is
  reshaping disease patterns. It’s not about fear, but awareness – understanding that invisible
  risks exist even without cigarettes.
  By recognizing these triggers early and acting consciously, we can begin to reclaim control
  over what we inhale, how we live, and ultimately, how we protect one of our most vital
  organs – our lungs.