In ovarian carcinoma, elevated serum concentrations of the aminoterminal propeptide of type-III procollagen are related to the clinical stage of the disease and to the presence of ascites, which contains very high concentrations of the propeptide. In a follow-up of patients with advanced disease, favorable clinical course was associated with normalizing propeptide values, whereas in progressing disease the values increased several weeks before clinical progression. In stable disease the concentrations were constantly above the reference range. Laminin and type-IV-collagen-related serum antigens were mostly within the reference range.