The present invention is directed to methods of diagnosing, prognosing, and managing treatment of cancer in a subject. These methods involve selecting a subject having cancer and obtaining, from the selected subject a population of either exomeres having a diameter less than 50 nm, small exosomes having a diameter of 60-80 nm, or large exosomes having a diameter of 90-120 nm, The exomeres, small exosomes, or large exosomes are recovered from the sample, and the exomeres, small exosomes, or large exosomes or portions thereof are contacted with one or more reagents suitable to detect: (1) higher or lower levels, relative to a standard for subjects not having cancer, or the presence or absence, of one or more proteins contained in said exomeres, small exosomes, or large exosomes, (2) higher or lower levels, relative to a standard for subjects not having cancer, or the presence or absence, of one or more N-giyeans contained In said exomeres, small exosomes, or large exosomes, (3) higher or lower levels, relative to a standard for subjects not having cancer, or the presence or absence, of one or more lipids contained in said exomeres, small exosomes, or large exosomes, (4) the presence or absence of one or more genetic mutations in nucleic acid molecules associated with cancer and contained in said exomeres, small exosomes, or large exosomes, or (5) combinations thereof. Cancer is then diagnosed, prognosed, or treatment Is modified based on this information.L'invention concerne des procédés de diagnostic, de pronostic et de gestion du traitement du cancer chez un sujet. Ces procédés impliquent la sélection d'un sujet atteint d'un cancer et l'obtention, à partir du sujet sélectionné, d'une population d'exomères possédant un diamètre inférieur à 50 nm, de petits exosomes possédant un diamètre de 60 à 80 nm, ou de grands exosomes possédant un diamètre de 90 à 120 nm. Les exomères, les petits exosomes ou les grands exosomes sont récupérés à partir de l'échantillon, et les ex
