Survival rates of patients with metastatic spinal cancer after scintigraphic detection of abnormal radioactive accumulation

Study Design. This retrospective study analyzes the timing of spinal metastases and the survivability of patients with cancer after the detection of spinal metastases. Objective. To evaluate the timing of spinal metastases in primary lesions and survivability of patients with metastatic spinal tumors. Summary of Background Data. Few studies have analyzed the influence of primary lesions on survival rates of patients with metastatic spinal tumors. Methods. This is a review of bone scintigraphy that was performed serially in patients with pulmonary cancer, breast cancer, prostatic cancer, cervical cancer, renal cancer, and gastric cancer from 1980 to 1991. To exclude false-positive cases, the spinal areas showing abnormal accumulation on bone scintigrams were further examined by other methods of diagnostic imaging. The timing of scintigraphic detection of spinal metastases and the survivability were studied in 425 patients with spinal metastases. The survivability after spinal accumulation was determined by the Kaplan-Meier survival curve. Results. The mean period, from the diagnosis of the primary lesion to the detection of abnormal accumulation in the spine, was shortest in pulmonary cancer (3.6 +/- 6.1 months), and it was longest in breast cancer (29.4 +/- 33.5 months). The 1-year survival rate was high in breast cancer (78%) and prostatic cancer (83%), and it was low in pulmonary cancer (22%) and gastric cancer (0%), respectively. The 6-month survival rate of gastric cancer was 15%. Conclusions. When managing metastic spinal tumors, it is essential to select therapeutic methods based on adequate consideration of the features of primary lesions and the expected prognosis.