title: The challenges of understanding cancer of unknown primary.
authors: Kari
authors: K
authors: Hemminki
authors: Matias
authors: M
authors: Riihimäki
authors: Kristina
authors: K
authors: Sundquist
authors: Akseli
authors: A
authors: Hemminki
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary*; D005260:Female; D006801:Humans; D008297:Male; D009362:Neoplasm Metastasis; D009382:Neoplasms, Unknown Primary / Q000401:mortality*