1. A method of treating a solid tumor cancer, comprising administering to a patient in need thereof a therapeutically effective amount of a phospholipid nonradioactive compound selected fromwhere X represents a) a non-radioactive isotope of iodine, or b) H n represents an integer of 12-30 and Y is selected from the group consisting of N+H3, HN+(R)2, N+H2N and R+(R)3Where R is an alkyl or arylalkyl substituent andwhere X represents a) a non-radioactive isotope of iodine, or b) H n represents an integer of 12-30 and Y is selected from the group consisting of H, OH, COOH, COOR and OR, and Z is selected from the group consisting of N+H3, HN+(R)2, N+H2N and R+(R)3Where R is an alkyl or arylalkyl substituent or a pharmaceutically acceptable salt thereof.2. The method of claim 1 wherein the phospholipid nonradioactive compound is selected from the group consisting of 18- (p-iodophenyl) oktadetsilfosfoholina, 1-O- [18- (p-iodophenyl) octadecyl] -1,3-propanediol-3- phosphocholine and where the non-radioactive iodine is the isotope.3. The method of claim 1 wherein the phospholipid nonradioactive compound has the formula:where I is a non-radioactive isotope of iodine, or a pharmaceutically acceptable salt thereof.4. The method of claim 1, wherein said solid tumor cancer is selected from the group consisting of lung cancer, breast cancer, glioma, squamous cell carcinoma, prostate cancer, melanoma, renal cancer, colorectal cancer, ovarian cancer, pancreatic cancer, gastric cancer and sarcoma.5. Combined pharmaceutical agent comprising a phospholipid radioactive compound selected fromwhere X is a radioactive isotope of iodine, n represents an integer of 12-30 and Y is selected from the group consisting of N+H3, HN+(R)2, N+H2N and R+(R)3Where R is an alkyl or arylalkyl substituent orwhere X is a radioactive isotope of iodine n represents an integer of 12-30 and Y is selected from the group consisting of H, OH, COOH, COOR and OR, and Z is selected from the group consisting of N+H3,
