Evaluation of bone scintigraphy and 18F-FDG PET/CT in bone metastases of lung cancer patients

Abstract

Objective

To compare the bone scintigraphy (BS) findings and PET/CT scintigraphy with FDG (FDG PET/CT) in the detection of bone metastases in lung cancer.

Material and methods

We studied 32 patients with lung cancer who underwent FDG PET/CT and BS in a period of 15.9 ± 18.6 days. The results of both techniques were compared with the histology, where available, radiological structural techniques and the clinical follow-up. In 30 patients, a definitive diagnosis was reached with the scintigraphic findings. No final diagnosis was obtained in 2 patients.

Results

BS was positive in 25/30 patients (83.3%) and negative in 5 patients. FDG PET/CT was positive in 21/30 patients (70%) and negative in 9. The BS and the FDG PET/CT were positive in 19/30 patients (63.3%) for the detection of bone metastases. In 6/19, both techniques showed the same number of bone lesions. In 10/19, FDG PET/CT showed a greater number of bone metastases than BS. In 3/19 patients, BS showed more lesions than FDG PET/CT and in 2/30 patients (6.6%), the BS was normal and the FDG PET/CT showed bone lesions which were confirmed as metastasis. In 6/30 patients (20%), the FDG PET/CT was negative and the BS was positive. BS and FDG PET/CT scan were normal in 3/30 patients (10%).

Conclusions

In patients with lung cancer, FDG PET/CT scan detected more metastatic bone lesions than BS. It also identified bone metastasis in negative BS. In our experience, when the BS was positive and the FDG PET/CT scan was negative, the lesions observed were mostly related with degenerative bone conditions and bone fractures. In the clinical practice, the FDG PET/CT and BS have a complementary role for the assessment of bone status in lung cancer patients.