Persistently elevated hCG in a patient with no clear evidence of pregnancy.

Background: We describe a case of a female patient with a complex medical history, including squamous cell carcinoma of the tongue, and persistent elevation in serum hCG and no confirmed intrauterine or extrauterine pregnancy.

Methods: The clinical chemistry laboratory was called upon to help clarify the situation and reach a diagnosis.

Results: Multiple potential sources of elevated hCG were considered and excluded.

Conclusions: This case shows a rare example of paraneoplastic hCG expression and highlights the role of the clinical chemistry laboratory in resolving diagnostic dilemmas and interpreting laboratory results in patients with multiple medical comorbidities.