Short summary

This study aims to elucidate the current use of FDG-PET/CT in patients with cancer of unknown primary tumor (CUP). This will be assessed in a retrospective study involving all patients who received the patho-anatomical CUP diagnosis at the Odense University Hospital (OUH) during the period 2014 to 2017. We hypothesize that 

a) time to final diagnosis was shorter in CUP patients who underwent FDG-PET/CT than in CUP patients who did not; 

b) DR is < 25% before or without the use of FDG-PET/CT and > 35% with FDG-PET/CT independent of the actual time point at which FDG-PET/CT was applied in the work-up process

Rationale

Cancer of unknown primary tumor (CUP) is generally defined as a category of histologically proven metastases, but with an unknown primary tumor at the time of diagnosis by conventional diagnostic methods. CUP accounts for 3-5% of all cancer malignancies, placing it among the top 10 cancers in terms of incidence and mortality among men and women. The prevalence of CUP (defined as "unknown and ill-defined cancers") in Denmark in 2010 to 2014 was 1035 patients which accounts for 2.4% (men) and 3.1% (women) of all cancer diagnoses in this period.

Results of a recent systematic review and meta-analysis from our department comprising 20 studies (with 1942 patients) extracted among 2953 potential articles suggested that the early use of FDG-PET/CT in CUP patients may improve the primary tumor detection rate (DR)

Description of the cohort

Patients are identified as potential CUP patients based on registrations made by the Department of Pathology at Odense University Hospital during the period 2014 to mid-2017. Mostly adults, both men and women.

Data and biological material

Pathology

Collaborating researchers and departments

Department of Oncology, Odense University Hospital

• Christina Junker Nyborg, MD
• Charlotte Kristiansen, MD

Department of Pathology, Odense University Hospital

• Clinical Associate Professor Karen Ege Olsen, MD

Department of Nuclear Medicine, Odense University Hospital

• Professor, Head of Research Unit., Poul F. Høilund-Carlsen, MD, DMSc
• Associate Professor Oke Gerke, Biostatistician, MSc, PhD
• Sara Wallenius, MD