Human Kallikrein 6 (hK6): A New Potential Serum Biomarker for Diagnosis and Prognosis of Ovarian Carcinoma

Purpose: The discovery of new ovarian cancer biomarkers that are suitable for early disease diagnosis and prognosis may ultimately lead to improved patient management and outcomes. Patients and Methods: We measured, by immunoassay, human kallikrein 6 (hK6) concentration in serum of 97 apparently healthy women, 141 women with benign abdominal diseases, and 146 women with histologically proven primary ovarian carcinoma. We then calculated the diagnostic sensitivity and specificity of this test and examined the association of serum hK6 concentration with various clinicopathologic variables and patient survival. Results: Serum hK6 concentration between normal and benign disease patients was not different (mean, 2.9 and 3.1 μg/L, respectively). However, hK6 in presurgical serum of ovarian cancer patients was highly elevated (mean, 6.8 μg/L; P < .001). Serum hK6 decreased after surgery (to a mean of 3.9 μg/L) in 68% of patients. The diagnostic sensitivity of serum hK6 at 90% and 95% specificity is 52% and 47%, ...