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

Abstract

Background Cancer of unknown primary (CUP) is a late-stage malignancy with poor prognosis, but we know little about what diagnostic tests and procedures people with CUP receive prior to diagnosis. The purpose of this study was to determine how health service utilisation prior to diagnosis for people with cancer-registry notified CUP differs from those notified with metastatic cancer of known primary. Methods We identified people with a cancer registry notification of CUP (n = 327) from the 45 and Up Study, a prospective cohort of 266,724 people �45 years in New South Wales, Australia, matched with up to three controls with a diagnosis of metastatic cancer of known primary (n = 977). Baseline questionnaire data were linked to population health data to identify all health service use, diagnostic tests, and procedures in the month of diagnosis and 3 months prior. We used conditional logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Results After adjusting for age and educational attainment, people with a cancer-registry notified CUP diagnosis were more likely to be an aged care resident (OR = 2.78, 95%CI 1.37-5.63), have an emergency department visit (OR = 1.65, 95%CI 1.23-2.21), serum tumor marker tests (OR = 1.51, 95%CI 1.12-2.04), or a cytology test without immunohistochemistry (OR = 2.01, 95%CI 1.47-2.76), and less likely to have a histopathology test without immunohistochemistry (OR = 0.43, 95%CI 0.31-0.59). Neither general practitioner, specialist, allied health practitioner or nurse consultations, hospitalisations, nor imaging procedures were associated with a CUP diagnosis.

Cancer-of-Unknown-Primary-Origin: A SEER–Medicare Study of Patterns of Care and Outcomes among Elderly Patients in Clinical Practice

“…While studying CUP using cancer registry-based [ 24 , 25 ] as well as linked cancer registry and claims data [ 17 , 26 , 27 ] provides important insights into the clinical features and care of these patients, challenges remain due to the lack of thorough clinical details and ability to delineate a clinically validated CUP population in cancer registries. CUP-specific, clinically tailored, and detailed databases would help promote further understanding of the disease.…”

“…Few studies are available that provide a detailed analysis of diagnostic work-up of CUP in population-based cancer registries (i.e., registry-notified CUP) [ 17 ] and, consequently, very little is known about contemporary real-world patterns of diagnostic work-up, treatment, and outcomes outside clinical trials. Among elderly patients (≥66 years of age) with registry-notified CUP from the US Surveillance, Epidemiology, and End Results (SEER)–Medicare (SEERM)-linked database, the specific aims of this study were to: (1) describe the demographic and clinical characteristics; (2) examine the use of diagnostic work-up; and (3) assess treatments and outcomes.…”

Healthcare Costs Before and After Diagnosis of Cancer of Unknown Primary Versus Ovarian Cancer in Australia

“…Anti-cancer therapies matched to the site of origin are the best therapeutic option for these patients; hence, a comprehensive diagnostic work-up is critically important. Many CUP patients do not receive a complete standard workup, often due to deteriorating health, lack of availability of diagnostic modalities or expert opinion [ 4 ]. Conversely, there may also be a risk of over-investigation, leading to a prolonged diagnostic odyssey.…”

Patient Characteristics Associated with Definitive Diagnosis of Metastatic Pancreatic Cancer in Those Initially Diagnosed with Cancer of Unknown Primary

“…However, older patients with comorbidities may be unable to complete the diagnostic workup necessary to make a de nitive diagnosis [14]. Unfavorable characteristics for de nitive diagnosis of CUP to a speci ed primary site including older age, epithelial/unspeci ed histology, and higher comorbid burden of disease correspond with current scienti c literature on CUP patterns of care, namely population-based studies focusing on patient characteristics and healthcare utilization [3,[15][16], adherence and diagnostic guidelines [10], and risk factors and clinical management [17][18].…”