The present invention features methods, devices, and kits for detecting a level of one or more biomarkers in a patient having cancer or determining the responsiveness of a patient having cancer to a treatment, such as treatment with a secretory phospholipase A 2 (sPLA 2 ) hydrolysable, cisplatin-containing liposome. The invention further includes methods of treating a patient having cancer by administering, e.g., the liposome.