Methods for detecting or diagnosing gynecological carcinomas in a patient are provided. One method involves assaying for the presence of lysophosphatidic acid in a plasma sample of the patient, is useful for detecting ovarian carcinoma, cervical carcinoma, endometrial carcinoma, and peritoneal carcinoma. In a preferred embodiment the method comprises: providing a blood specimen from the patient, obtaining a plasma sample for the blood specimen under conditions which minimize the release of lysophosphatidic acid from the platelets in the blood specimen into the plasma, extracting lipids from the plasma, and detecting the presence of lysophosphatidic acid in the lipid. Another method involves assaying for the presence of lysophosphatidyl inositol in a bodily fluid, preferably plasma, from the subject. Another method involves assaying for the presence of lysophosphatidic acid and lysophosphatidyl inositol with rising level in a bodily fluid from the subject. |