Tuesday, September 2, 2014
Metastatic thoracic disease
81 year old female had a right axillary lymphadenectomy following a diagnosis of stage 3 right axillary melanoma of unknown primary. 1 out of the 16 was confirmed metastatic melanoma by melana immunostain on 2/8/08. Patient had Pet/CT scan wholebody imaging was done on 8/16/08. Impression: Development of metastatic thoracic disease with a large carinal node 2.3 cm demonstrating avid abnormal FDG uptake with a maximum SUV values of 48. There is also development of 2 left hilar lymph nodes which were difficult to measure given the adjacent vascularity however both demonstrate avid abnormal FDG uptake with maximum intensity units of approximately 17 and 27. There is also development of 2 left lower lobe pulmonary nodules measuring 1 and 1.4 cm. These also demonstrate avid abnormal FDG uptake with maximum SUV values of 15 and 20 respectively. No soft tissue nodules or other evidence of abnormal FDG uptake. Normal tracer excretion is seen. Can you please tell me in laymans terms what exactly this diagnosis means and possible surgery/treatment options. I am not a dr. and do not understand this at all.
PET scans demonstrate elevated metabolism (burning energy) by looking at the uptake of labeled sugar (FDG). Elevated energy use is typical of cancer, as well as infection or injury, so it can point out areas suspicious for cancer spread, although it does not prove cancer. When a PET scan is performed in combination with a CT scan, the suspicious areas on PET can be compared to the CT to accurately define the anatomic location that is suspicious. In the situation that you describe, avid FDG uptake (areas suspicious for cancer by PET scan) is correlated with the masses found on CT scan that include:
-carinal node (a lymph node in the center of the chest where the trachea divides into the two main bronchi)
-left hilar nodes (lymph nodes at the "root" or central attachment of the left lung)
-left lower lobe pulmonary nodules (in the left lower part of the lung)
In summary, the findings are highly suspicious for spread (metastasis) of the melanoma. Rarely, metastases (cancer that has spread) can be removed surgically. This might be the case when there are very few nodules that can all be completely removed. In the situation you describe, I suspect that surgery will not be an option due to the number of spots and their location. More likely, if treatment is planned, a systemic therapy such as chemotherapy would be offered. Of course, the patient should meet with an expert, such as an oncologist (cancer specialist), who can carefully review her medical history and studies, and then discuss management options.
Michael F Reed, MD
Assistant Professor of Surgery
College of Medicine
University of Cincinnati