Wei-Jen Shih MD, Presenter: Nothing to Disclose

George Lee Shih MD, MS, Abstract Co-Author: Co-founder, Vitesso, LLC

Primo P. Milan MD, Abstract Co-Author: Nothing to Disclose

We frequently observe cold areas in vertebrae on FDG PET studies especially after tumor irradiation. These findings are neither new and nor unexpected; however, they are not yet systemic evaluation and documented. To evaluate the causes of this finding and their significances, we are retrospectively reviwed FDG PET images in two-years period.

We reviewed the FDG PET images of 230 patients retrospectively. The locations of photon-deficient areas were divided into cervical, thoracic, lumbar, or sacral region. The cause of photon-deficient areas was divided into 2 categories: malignant and non-malignant. The malignant category included the following externally irradiated malignancies (n=37, patient mean age=72.27): non-small cell lung cancer, n=17; small cell lung cancer n=3; head and neck squamous cell carcinoma, n =11; rectal, n=3; Hodgkin, n=1; prostate, n=1). There were th four cases of non-malignancies (mean age=66): 2 compression fractures, one hemagioma, and one false positive due to lumbar scoliosis were the etiologies of the non-malignancies.

A total of 37 patients were included in this analysis of radiation-induced absent-reduced uptake in cervical vertebrae or cervical and upper thoracic vertebrae. All lung malignancies, the Hodgkin disease and the esophagus carcinoma induced cold areas in the thoracic or the cervial and thoracic vertebrae. All rectal carcinoma patients had cold areas in the lumbar-sacrol vertebrae. One prostate carcinoma caused absent activity in the lumbar-sacrol vertebrae. Hemagioma and compression fractures caused cold vertebrae in the lumbar vertebrae area. In one patient with lumbar scoliosis there was a false positive on sagittal sections. A total of 33 of 37 patients (89.19%) exhibited cold areas in the cervical and thoracic vertebrae.

The majority (nearly 90%) of absent uptake in vertebral bone marrow located in cervical or/and thoracic and upper thoracic vertebrae is caused by irradiation to treat the lung malignancies and head and neck squamous cell carcinoma.

The majority of photon deficient area in the bone marrow vertebrae is due to radiation therapy of lung malignacies and head and neck malignancies.

Shih, W, Shih, G, Milan, P, Photon Deficiency of the Vertebrae on F-18 FDG PET Imaging Study.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6012452.html