Dr. Nguyen Minh Duc, a lecturer at Pham Ngoc Thach University of Medicine (Ho Chi Minh City), recently reported that he examined a 63-year-old female patient who had been experiencing persistent headaches and dizziness. Initially, the patient believed she was only suffering from vestibular disorder, so she was complacent and mentally prepared to “live with the condition.”

However, as her symptoms became increasingly frequent and severe, she eventually decided to seek medical attention. MRI results revealed multiple metastatic lesions of adenocarcinoma. A subsequent chest CT scan detected a large tumor at the base of the left lung, confirming advanced-stage lung cancer that had metastasized to multiple organs, including the brain. The prognosis was extremely poor.

According to Dr. Duc, when reviewing the patient’s medical history, she stated that she had never smoked, maintained a healthy lifestyle, and did not work in a toxic environment. However, her husband and son were heavy smokers, often smoking inside the house and even in enclosed rooms.

Diagnosed with end-stage lung cancer with brain metastasis, the woman broke down in tears upon learning that the “culprit” came from her own family.
Image: MRI showing metastatic lesions (Photo provided by the doctor).

The patient shared that her husband had passed away and that she currently lives with her son, who continues to smoke a pack of cigarettes a day. Having been exposed to cigarette smoke for many years, she no longer felt discomfort. However, she was unaware that secondhand smoke was in fact the primary cause of her lung cancer.

Dr. Duc said that when it was explained to her that both active and passive smoking can lead to lung cancer, the patient burst into tears, deeply worried about the health of her son and grandchildren.

Tobacco accounts for up to 80% of lung cancer cases

According to Dr. Duc, this is not a rare case. He has treated many women who developed lung cancer after long-term exposure to cigarette smoke from their fathers, husbands, or children.

The majority of lung cancer cases are caused by inhalation of tobacco smoke. Global statistics indicate that approximately 80% of lung cancer cases are linked to cigarette smoke. Toxic substances in tobacco smoke can remain in the lungs for extended periods, gradually altering cellular structures and eventually leading to cancer.

Notably, not only active smokers are at risk, but passive smokers—those who unintentionally inhale cigarette smoke—also face a high risk, sometimes even higher than that of direct smokers.

“Secondhand smoke contains more than 7,000 chemicals, including at least 70 known carcinogens such as benzene, formaldehyde, and arsenic. It not only causes lung cancer but also increases the risk of stroke, cardiovascular disease, nasopharyngeal cancer, and bladder cancer, while posing serious health threats to women and children within the household,” Dr. Duc warned.

In addition to tobacco, other risk factors for lung cancer include exposure to radiation (radon), asbestos, arsenic, nickel, chromium, as well as air pollution, dust, and family history of cancer.

According to oncology experts, early-stage lung cancer often presents no typical symptoms, making it difficult to detect or easily mistaken for common respiratory illnesses. When clear symptoms such as persistent cough, coughing up blood, shortness of breath, or chest pain appear, the disease is often already at an advanced stage, significantly complicating treatment.

Alongside proactive prevention by eliminating risk factors, screening and early detection of lung cancer remain top priorities to maximize treatment effectiveness.

Cancer screening involves detecting the disease before symptoms appear, allowing cancer to be identified at an early stage and improving treatment outcomes. Once obvious symptoms develop, the cancer may have already spread, reducing the chances of successful treatment.