SURVIVAL IMPACT OF SKELETAL METASTASIS ON BONE SCINTIGRAPHY IN PATIENTS WITH GERM CELL TUMOURS

Objective: Our aim was to determine the frequency of skeletal metastasis in germ cell tumours (GCT) at baseline and relapse on conventional technetium-99m methylene diphosphonate (Tc-99m MDP) whole body bone scan (bone scan) and to evaluate the effect of bone metastases on survival. Materials and Methods: Electronic medical records of histologically proven GCT over 64 months were retrospectively analysed. Basic demographic and histologic information were correlated with the presence of osseous and visceral metastases. 5-year disease-free survival (DFS) and overall survival (OS) were calculated in presence, the absence of bone metastases at baseline and at relapse. Results: A total of 130 gonadal and extragonadal GCT patients underwent Tc-99m MDP bone scans; four with insuf cient data were excluded from the study. 47% were females and 53% were males with the age range of 1 month – 72 years. 105 (83%) were under 18 years of age. Osseous metastasis was detected in 12 (9.5%). Two (17%) had solitary and 10 (83%) had multifocal skeletal metastases. Clinically, 83% had localised bone pain. Osseous metastases were more frequently associated with mixed GCT and yolk sac tumour. 50% of mediastinal GCT developed bone metastases. 42% died within 4–18 months. There was a statistically signi cant impact of visceral metastases on DFS and OS. OS at 5 years in patients without bone metastases, with bone metastases at baseline and bone metastases at relapse, was 77%, 38% and 75%, respectively. 5-year DFS for the same cohort groups was 63%, 38% and 20%, respectively. Conclusion: Osseous involvement was found in 9.5% of GCT patients undergoing diagnostic Tc-99m MDP bone scan. Baseline skeletal evaluation for metastases should be done, particularly in the case of bone pains or known systemic metastases. Although skeletal relapses are rare, they have a grim outcome. Key words: Bone scintigraphy, germ cell tumours, skeletal metastases