Hi Vi; first of all, kudo's to you for being a survivor and such an effective advocate for your husband in his time of need!
Your question about staging is a good one; I found an informative site from the American Cancer Society and have posted the link for you, followed by an excerpt that hopefully answers your question:
Staging
http://www.cancer.org/docroot/ETO/content/..._2X_Staging.asp
A Cancer’s Stage Does Not Change
"An important point some people have trouble understanding is that the formal "stage" of a cancer does not change over time, even if the cancer progresses. A cancer that comes back or spreads is still referred to by the stage it was given when it was first diagnosed.
For example, if a woman was first diagnosed with "stage II breast cance," but the cancer now has spread to the bones, the cancer is called "stage II breast cancer with recurrent disease in the bones" (if the cancer went away with treatment) or "stage II breast cancer with metastasis in the bones" (if the cancer never went away completely). This is not "stage IV breast cancer". A stage IV breast cancer refers to a cancer that has already spread to a distant part of the body when it is first diagnosed. A person keeps the same diagnosis stage, but more information is added to the diagnosis to explain the current disease status. (The treatment of a stage II cancer with metastasis and a stage IV cancer may be the same, however.)
This is important to understand because survival statistics and treatment by stage information on specific cancer types refer to the stage when the cancer was first diagnosed. The survival statistics related to stage II breast cancer that has recurred in the bones may not be the same as the survival statistics for stage IV breast cancer.
Sometimes, after a period of remission (cancer being undetectable) for certain cancers, if more treatment is planned, a doctor might restage the cancer. This will mean going through the same process that was done when the cancer was first diagnosed: exams, imaging tests, biopsies, and possibly surgery to restage the cancer. If the cancer is restaged, the new stage will be recorded with a lower case "r" before the restaged designation. This is not often done."
Hope this helps,
Lolly