Routine bone scintigraphy in primary staging of soft tissue sarcoma; Is it worthwhile?

Abstract

The incidence of bone metastases in soft tissue sarcoma (STS) patients seems to be low but has not been studied separately. In this study, the authors aimed to determine the value of routine radionuclide bone scanning in preoperative staging of STS patients. Preoperative bone scans were evaluated retrospectively in 109 consecutive patients (median age, 44 years; range, 1-86) with intermediate or high grade STS. Scans were scored in 3 categories: 1, metastases very likely; 2, equivocal; and 3, normal or benign lesions. Category 1 scans were found in 8 of 109 patients (7%); in all 8 patients, bone metastases were confirmed. Six of these eight patients reported pain, and all had additional lung, bone marrow, or lymph node metastases. The highest rate (17%) was found in the rhabdomyosarcoma subgroup (n = 18). Category 2 (equivocal) scans were present in 12 of 109 patients (11%), in all of which bone metastases were excluded through additional investigations. Category 3 (normal) scans were found in 81%. Bone metastases were at least as frequent as lung metastases (4%) and were the single site of systemic disease in 4%. The rate of bone metastases was 55% in patients with bone pain versus 2% in patients without pain. Bone metastases in primary STS patients are rare (7%) yet in this study at least as frequent as lung metastases. The low rate in asymptomatic patients versus the high rate in symptomatic patients supports the use of bone scanning in symptomatic patients only. The yield of routine bone scanning is low.