Misdiagnosis of superior sulcus tumours: a scoping review.

Background: Superior sulcus tumours (SSTs) are a rare but serious non-small cell lung cancer that requires aggressive multi-modal intervention. Existing literature suggests patient outcomes are adversely affected by diagnosis delay, often from misdiagnosis as a musculoskeletal condition. As such, the aims of this review were to identify the key clinical features of SSTs documented in the literature and differentiate them from commonly misdiagnosed musculoskeletal pathologies. Methods: In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for scoping reviews (PRISMA-ScR), a systematic search of electronic databases was conducted for studies of SST patients with descriptions of their signs and symptoms. These findings along with information on any length of diagnostic delay or misdiagnosis were extracted for analysis. Results: The final review included a sample of 1,328 patients across 31 studies. A total of 111 patients had a misdiagnosis resulting in diagnostic delay. The most common presentation across all SSTs was shoulder pain (60.0%), followed by a history of smoking (27.0%), and arm pain (25.6%). Diagnostic delay was most frequently due to radiographic error by primary contact physicians. For patients who received a misdiagnosis, the most common clinical findings were signs and symptoms of upper limb neuropathy (55.7%), shoulder pain (53.2%) and chest pain (27.9%). Within this subgroup, SSTs were most frequently misdiagnosed as cervical spine radiculopathy, cervical spine osteoarthritis, or glenohumeral osteoarthritis. Additionally, within the misdiagnosis subgroup, key features of SSTs such as Horner's syndrome and history of smoking were less prevalent compared to the larger group. Conclusions: Explicit testing and differentiation between shoulder and cervical spine pathology are required when examining patients with atraumatic shoulder and/or arm pain to rule out SSTs. Specifically, targeted testing for cervical spine radiculopathy and glenohumeral osteoarthritis can help guide appropriate imaging in the initial stages of assessment. When requested, apical lung imaging should be scrutinized to prevent physicians from missing radiographic signs of SSTs that may lead to diagnostic delay.