How fast can lung cancer grow in my 50-year old brother?

Question

Hello doctor,

I am asking about my brother, who is 50 years old and has been a heavy smoker for nearly 25 years (about 25 cigarettes a day). About seven months ago, he had a CT scan for something unrelated, and they found a small 6 mm nodule in his right lung. The radiologist said it was likely benign and recommended a follow-up scan in six months.

He had the follow-up scan last week, and the nodule has grown to 14 mm. They are now talking about doing a PET scan and possibly a biopsy. We are terrified. The pulmonologist mentioned terms like “suspicious features” and “irregular margins,” and we do not fully understand what that means.

My main question is: how fast can lung cancer grow in a 50-year-old smoker? The growth from 6 mm to 14 mm in seven months seems very alarming to us. Is this rate of growth typical for lung cancer, or could it still be something else?

His LDH levels came back slightly elevated at 280 U/L. He also has COPD and is on Tiotropium. Can COPD make lung nodules grow faster?

We need to understand what we are dealing with before the biopsy appointment next week.

Please advise.

Thank you.

Answer 1

Hello,

Welcome to icliniq.com.

Thank you so much for sharing your concern with me.

I can understand how frightening this situation feels, especially after seeing that change in the scan.

An increase from 6 mm to 14 mm over seven months is something we do take seriously. This kind of growth can be seen in lung cancer, which is why your pulmonologist is being cautious. When they mention irregular or suspicious margins, they mean that the edges of the nodule are not smooth and well-defined, which sometimes raises concern compared to more benign-looking nodules.

At the same time, this does not automatically mean it is cancer. There are a few non-cancerous conditions, including certain infections or inflammatory nodules, that can also increase in size. But given your brother’s long smoking history, we have to evaluate it carefully and not assume it is harmless.

Regarding growth rate, lung cancers can behave very differently. Some grow slowly, while others can increase in size over months. What you are describing is not unusually rapid, but it is significant enough that further testing is definitely needed.

COPD (chronic obstructive pulmonary disease) itself does not make a nodule grow faster, but it is often seen in people with long-term smoking exposure, which increases the overall risk. The mildly raised LDH (lactate dehydrogenase) does not point specifically toward cancer and is not something we rely on for this decision.

At this point, the plan advised to you is the correct one. A PET (positron emission tomography) scan helps us understand how active the nodule is, and the biopsy will give a clear answer. I have seen similar situations where early diagnosis allowed timely treatment, so taking the next steps without delay is important.

I hope this explanation helps, and if you have any further questions, please feel free to ask at any time.

Thank you.