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"When should a primary care physician refer a patient to an oncologist?"

ZocdocAnswersWhen should a primary care physician refer a patient to an oncologist?


An 8mm, irregular in shape, nodule is detected on the left lung by CT scan in a patient with a history of bladder cancer.


Lung nodules are commonly detected on CT scans that are performed for a wide variety of reasons, other than looking for cancer. However, once a nodule is detected, the dilemma is deciding what exactly is the risk that this nodule represents cancer and what to do about it. That is why you should discuss your concern with your doctor. The first thing the doctor needs to do is estimate this risk. In your case, the prior history of bladder cancer (which can sometimes metastasize to the lungs) is concerning. Additionally, nodules with an irregular shape are more likely to be cancerous, as are nodules larger than about 8 mm (your nodule being right at that border for size). All in all, this means at the very least that you are not "low risk" for this nodule being cancerous, and further evaluation is probably needed. There are several strategies that can be used in this setting. One is to perform serial CT scans to see if the nodule grows larger (if it grows, it is more likely to be cancerous, and biopsy is required). Another option is to perform a special type of CT scan, called a PET scan, which is more sensitive for picking up cancer. These are all tests that your primary care doctor can manage, but given your history of cancer, I think it would also be very reasonable to contact the oncologist who previously managed your bladder cancer and get their input!

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