A cough that lasts longer than three weeks or sudden weight loss without changes in diet can signal early-stage cancer, according to medical oncologist Bradley Scott Colton.
Early cancer symptoms often mimic common health problems, but they tend to worsen over time rather than resolve.
Bradley Scott Colton (USA) and internist Jay Luthar (USA) outlined these red flags. Tumors in the airways disrupt normal lung function, causing altered breathing patterns or persistent coughing, Luthar explained.
“Patients may experience shortness of breath when climbing stairs, even though they previously had no trouble with the activity,”
Luthar told Vietnam.vn.
Alongside lung cancer, a chronic cough can stem from asthma, respiratory infections, or chronic lung conditions. When linked to malignancy, it may accompany chest pain, hoarseness, fatigue, recurrent respiratory infections, coughing up blood, or unexplained weight loss.
Luthar advised seeing a physician if a cough persists past three weeks, changes significantly in character, or triggers breathlessness during simple tasks. Weight loss tied to cancer often pairs with fatigue, weakness, or feeling full faster than usual, according to Luthar.
Changes in bowel habits serve as another warning sign for colorectal cancer. A growing tumor can obstruct the colon or irritate the mucosal lining, leading to sudden constipation, diarrhea, or narrow, ribbon-like stools lasting for weeks.
Patients dealing with bowel changes may also experience abdominal pain or rectal bleeding. Colton recommended seeking medical evaluation if these symptoms persist for two to three weeks.
“If you have bloody stools, severe abdominal pain, or unexplained weight loss, you should consult a doctor immediately,”
Colton told Vietnam.vn. He also urged everyone to participate in recommended screenings, including colonoscopies.
Cancer-related fatigue differs fundamentally from ordinary tiredness and fails to improve with rest. Colton said that tumors consume substantial energy while releasing inflammatory proteins or causing internal bleeding that results in severe anemia.
Medical providers stress that symptoms like chronic coughing, bowel habit shifts, and rapid weight loss do not automatically confirm a cancer diagnosis. Benign conditions frequently share these clinical presentations, making clinical diagnostics essential.
