Had an mri of a lung nodule that is non calcified ... slow growing since 2001... 9mm... radiologist made diagnoses of it being benign . how can he make such a diagnoses without truly knowing isn't a ct pet scan better to show or even a biopsy?

None of the above: Kind of confusing story. We don't usually do an MRI of the lung to get that answer. Was it a ct scan? There are only three ways we can prove a nodule is benign, each with its pluses and minuses. One is a clear radiographic appearance (calcium or fat within the nodule), two is to demonstrate the absence of growth over sufficient time, and three is take it out.

D/w your MD: It looks like a benign tumor--over 11 years- it grows slowly and the size is only 9mm. If this were a cancer, the growth will be way more rapid than this is. A pet scan has some degree of false negativity when the size is < 10mm. A biopsy is invasive and it's not easy to do when the size is small. Would recommend surveillance only, & quit smoking .If you smoke. (btw, ct scan is better than mri).

See below: This may be an intrapulmonary lymph node and not a tumor at all. Radiologist probably made diagnosis based on the fact that it is very small and relatively stable over 11 years. Growth is very difficult to gauge with spots of that size. At any rate, it is too small for a meaningful pet or a biopsy. A ct is always better than a MRI for lung problems. Good luck!

Very slow growth: Perhaps the growth is so slow as to make malignancy unlikely. Discuss the specifics with your doctor. It is always better to compare same modalities (ct with ct). Ct is better than MRI for evaluating the lungs because of quicker scan time. Pet/ct can be nondiagnostic at this size. Biopsy has its own risks and is harder at this size.

Choices: 12 years with minimal change suggests benign may still calcify inflammatory- granulomas can change a bit also removal is always an option but we try to, weigh risk versus benefit. Ct is good for regular followup. Pet can be positive with some inflammation, but a negative would be encouraging.