Health service utilisation and investigations before diagnosis of cancer of unknown primary (CUP): A population-based nested case–control study in Australian Government Department of Veterans’ Affairs clients

Comorbid chronic diseases and cancer diagnosis: disease-specific effects and underlying mechanisms

“…Efforts to prevent emergency presentations are justified because such diagnoses are associated with worse clinical outcomes and patient experience 14,37,38 . The majority of evidence suggests that patients affected by chronic conditions have a higher risk of diagnosis of cancer as an emergency 31,37,[39][40][41][42][43][44][45][46][47][48][49][50] (Figure 1). An English study on emergency diagnosis of any cancer reported a 1.3 risk ratio for patients with Charlson comorbidity score of 1 versus 0 49 .…”

Diagnostic and health service pathways to diagnosis of cancer-registry notified cancer of unknown primary site (CUP)

“…As the NSW Cancer Registry only provides the month and year of cancer diagnosis, we ascertained all health services in the entire month of diagnosis. We focused on the month of diagnosis and the three months prior to diagnosis based on our previous work showing that health service utilisation increased around this time [8], and clinical advice that this was the most relevant time period for diagnostic investigation. We confirmed that these observations held true for our cohort (data not shown).…”

“…While a diagnosis of CUP ideally should be limited to people with a histological confirmation of metastatic cancer, in whom thorough testing has failed to identify the site of the primary tumor, people registered with a diagnosis of CUP in population-based cancer registries are heterogeneous, with many people receiving a diagnosis based on clinical examination only. [4,5,[8][9][10][11] Thus, it is difficult to compare population-based studies of registry-notified CUP to cases series of "true CUP" cases, who have received exhaustive investigations.…”

“…Studies of how people diagnosed with CUP interact with the health system prior to their definitive diagnosis, and what investigations they receive, are limited. [8,12] Although there are no Australian CUP clinical practice guidelines, the US National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO) CUP-specific guidelines support the judicious use of diagnostic investigations, in keeping with a patient's prognosis and treatment options. [13,14] Yet, the diagnostic pathway of patients with a cancer-registry notified CUP diagnosis is highly variable, [8,15,16] which may reflect heterogeneity in clinical presentation and patient characteristics.…”

“…Previous studies suggest that the diagnostic pathway for people with CUP differs compared to people diagnosed with other cancers, including late-stage cancers of known primary site. [8] CUP appears more likely to be diagnosed following an emergency department visit compared with all other cancers, and diagnosis may involve less specialist input and fewer invasive diagnostic procedures, including histopathological diagnosis of cancer. [8,15] In this prospective Australian cohort study, we sought to compare the pathway to diagnosis for people diagnosed with a cancer-registry CUP diagnosis, compared with people diagnosed with metastatic cancer of known primary site.…”