Introduction: Degenerative changes of the spine are common in obese cancer patients and are frequently confusing during
the interpretation of bone scan of those patients. Aim: To investigate the influence of body weight on the frequency of degenerative spine disease in a cohort of cancer patients using technetium-99m methylene diphosphonate (Tc-99m MDP) bone scan. Methods: A prospective study of 100 cancer patients with or without back pain referred for bone scanning. Their mean age was 58.5±10.2 years and 46% were males. Tc-99m MDP bone scan was done followed by spinal magnetic
resonance imaging (MRI) examination. Patients were divided into two groups according to the body mass index (BMI) into
group 1 including 60 overweight and obese (BMI ≥ 25) patients and group 2 including 40 non-obese (BMI < 25) patients
serving as a control group. Any spot of enhanced radiotracer uptake at any part of the vertebrae was considered abnormal
and correlated with MRI findings. Results: A total of 168 vertebral lesions were detected by bone scan (150 in group 1 and 18 in group 2) with significant difference between both groups and between different grades of obesity in group 1. All lesions were accurately localized and proved to be of degenerative nature by MRI. The percentage of patients with back pain in group 1 was significantly higher than in group 2 (65% vs. 35%, respectively). Conclusion: Bone scintigraphy is a good technique to detect degenerative spinal disease in obese cancer patients.