Background: We aim to characterize the workup received by and identify any delays to diagnosis or treatment in patients referred to a tertiary cancer centre with the diagnosis of squamous cell carcinoma in neck node(s) and no identifiable primary (SCCNIP).
Methods: Over 1 year, 68 patients were initially referred to the Head and Neck clinic with a label of "primary unknown". After extensive workup, 29 of the 68 patients were found to have pathologically confirmed SCCNIP. For these 29 patients, imaging tests, biopsies, examinations and times to treatment were reviewed and compared to 145 patients referred for known primaries.
Results: In 21/29 (72%) patients, ultrasound was ordered prior to biopsy or referral. After referral, the first imaging test used was CT neck in 28 patients and PET/CT in 1 patient. Median time from referral to primary identification (n = 23) or workup completion (n = 6) were 16 (range: 0-48) and 36 (17-82) days respectively. Median time from referral to treatment was 55 (27-90; n = 26) days and was longer than those referred for known primaries (48 days; 20-162; p < 0.001). Across all patients, median time between first diagnostic imaging test and pathologic diagnosis were 20.5 and -8.0 days (p < 0.0001) in patients receiving ultrasound and CT, respectively.
Conclusions: In our cohort, delays to management were linked to community use of ultrasound and scheduling of both CT and PET/CT after thorough head and neck examination in patients with SCCNIP.
Keywords: Diagnostic workup; Diagnostics; Head and neck; Neck node; Squamous cell carcinoma; Treatment delay; Unknown primary.