Effectiveness of two Palliative Radiotherapy Regimens (20 Gy in five fractions versus 8 Gy in one fraction) for Thoracic Spine Bone metastases. Experience of Saudi Arabia

Background: In spite of wider use of 8 Gy in one fraction palliative radiotherapy regimen for bone metastases in the Western world, data is scantly in the Middle East. We aimed to compare a single dose of 8 Gy vs. 20 Gy in 5 fractions for thoracic spine metastases.
Materials and methods: Forty patients with metastatic breast, prostate and lung cancers were randomized to receive a single dose of 8 Gy (n =20) vs. 20 Gy in 5 fractions (n =20) for thoracic spine metastases. Relief of pain and intensity was assessed prospectively via a pain questionnaire prior to treatment and every 4 weeks thereafter, using a 4-point scale (none, mild, moderate, severe), along with need for types of analgesic drugs and doses taken.
Results: Complete pain relief was achieved in 9 patients (45%) treated with one fraction of 8 Gy and in 11 patients (55%) who received 20 Gy in 5 fractions (P=0.61). Similarly, no difference between the two treatment regimens according to duration of pain relief (medians of 9 and 9.5 months, respectively) P = 0.42. No difference in nausea and vomiting (N&V) was seen (5 patients in 20 Gy in 5 fractions vs.7 patients in 8 Gy in one fraction), However, N&V was significantly prolonged in patients who received 8 Gy in one fractions (15 days vs. 7 days in 20 Gy in 5 fractions) P =0.03.
Conclusions: No difference in pain relief and duration was noticed between two palliative radiotherapy regimens (8 Gy in one fraction vs. 20 Gy in 5 fractions) for painful thoracic spine metastases, however, nausea and emesis was prolonged with single fraction of 8 Gy, which warrants further larger trials of 8 Gy in single fractions in painful thoracic spine metastases.