PET CT vs. Mediastinoscopy - 1261048

A mediastinoscopy is usually done at the beginning of surgery. Knowing for sure what's happening with nodes in the mediastinum is important enough to check with mediastinoscopy. A pet scan might pick up infection/inflammation. Here are a few blogs on the subject, http://cancergrace.org/lung/tag/mediastinoscopy/ (search terms on grace, "surgery mediastinoscopy"
Janine

That's a controversial question: essentially, it's whether a mediastinoscopy should be done in a "clinically/radiographically negative" mediastinum. Surgeons have different views, but I think more expert thoracic surgeons favor a mediastinoscopy in this situation for all but the lowest risk cancers, such as a very small (<1-2 cm) nodule that is located peripherally, near the outer portion of the lungs.

overall, while some would consider this unnecessary, it's definitely NOT gratuitous, and many very well trained thoracic surgeons would strongly err on the side of favoring a mediastinoscopy even if the imaging doesn't show findings suggestive of lymph node involvement, because a sizable minority (I believe around 15%) of patients will actually have lymph node involvement despite a negative CT or PET/CT.

Good luck.

-Dr. West

Mediastinoscopy is considered the gold standard test, because you know for sure whether the sampled lymph nodes are involved with cancer or not by looking at the tissue under the microscope. PET/CT has both a false positive rate (node lights up due to nonspecific inflammation) and also a false negative rate (a cancerous node that doesn't light up).

It is usually a good idea to surgically stage the mediastinum, since these results may influence post-surgery decisions to give chemotherapy or radiation.

Hope this helps.