Early Referral to Orthopedic Surgeon Prevents Skeletal Related Events: A Comparison of Patients with Cancer of Known and Unknown Primary Origin at Initial Presentation in a Musculoskeletal Department

Purpose: To identify optimal orthopedic surgical intervention by comparing cases of bone metastasis in cancer of known and unknown primary origin at initial presentation. Methods: Twenty-two patients with bone metastasis who were referred to us between 2011 and 2014 were retrospectively assigned to two groups based on their initial presentation: the known primary origin (known) group and the unknown primary origin (unknown) group (n = 11 each). Data analyzed included local therapy, orthopedic surgeon involvement, response and complications at the metastatic site, and individual outcomes. Results: In the known group, all 11 patients underwent radiotherapy (RT) as the initial treatment and 4 underwent secondary surgery (wide resection in 2 patients and palliative surgery in the remaining 2). In the unknown group, in which the orthopedic surgeon was involved early in local therapy for bone metastasis, 6 underwent RT and 5 underwent orthopedic surgery as the initial treatment (wide resection in 3 patients and palliative spinal surgery in the remaining 2), with 2 patients requiring secondary RT. There were significantly more cases of progressive disease (PD) in the known group (p = 0.004). The complication rate was 18.2% in the known group and 0% in the unknown group. Conclusion: All patients in the unknown group, who received early involvement from the orthopedic surgeon, showed better local control. Therefore, as soon as skeletal metastatic lesions are identified, orthopedic surgeons have an important role to play in defining the treatment strategy.