survival rates for IIa patients

I saw your response to a question regarding survival statistics and your reply was stage IIa and IIb patients only have a five year survival rate of 65% approx.  All of the information I have reviewed ACS, NCI, etc... put statistics for IIa 5 year survival over 80%.  Is there a reason for the lower number you used or are the other statistics inflated.  I know statistics vary and every patient's case is unique but I am curious and concerned because my wife, although told by our oncologist that she was stage I, is probably a stage IIa patient.  Tumor was 3.5 cm when removed with no positive lymph nodes or evidence of spread to bones or soft tissue.  Are your numbers based on your facility?  Thanks for your assistance.

[CCF-RN,MSN-rf]

Dear Manson:  It's all a matter of what source you read.  These are not numbers from our facility.  Rather, they are numbers from books.  For example, the 65% you read was from "Everyone's Guide to Cancer Therapy 3rd ed.," edited by Dollinger, Rosenbaum and Cable, published by Somerville, 1997 (the most recent edition).  In this book, stage llA and llB are combined in the discussion.  However, The "American Joint Committee on Cancer 5th ed.," published by Lippincott, 1998 gives different numbers and describes them in terms of observed and relative survival rates.  I will include the entire description:

Staging is done by the TNM staging system.  T stands for tumor, N for nodes, and M for metastasis.  Here's how it works:

T1 - tumor 2cm or less in greatest dimension
T2 - tumor more than 2cm but less than 5cm in greatest dimension
T3 - tumor more than 5cm at greatest dimension
T4 - tumor of any size attached to the chest wall or skin

N0 - no regional lymph node metastasis
N1 - metastasis to movable lymph nodes in the armpit on the
     breast cancer side
N2 - metastasis to the lymph nodes in the armpit on the breast
     cancer side that are attached to each other or attached to
     other structures
N3 - metastasis to the mammary lymph nodes on the same side as
     the breast cancer

M0 - no distant metastasis
M1 - distant metastais (includes supraclavicular lymph nodes)

Stage I    - T1     N0     M0
Stage IIA  - T0     N1     M0
           - T1     N1     M0
           - T2     N0     M0
Stage IIB  - T2     N1     M0
           - T3     N0     M0
Stage IIIA - T0     N2     M0
           - T1     N2     M0
           - T2     N2     M0
           - T3     N1     M0
           - T3     N2     M0
Stage IIIB - T4     any N  M0
           - any T  N3     M0
Stage IV   - any T  any N  M1

5 year survival based on stage (AJCC Staging Manual, 1998)

Stage I    - 87-98%
Stage IIA  - 78-88%
Stage IIB  - 68-76%
Stage IIIA - 51-56%
Stage IIIB - 42-49%
Stage IV   - 13-16%

Please keep in mind that in order to have 5 year survival data, the numbers must be at least 6 years old assuming the data were all collected the same year.  Also, take into account the year of publication and the data are even older.  In the last 10 years, many new treatments have been developed that have likely improved survival - but we won't know that statistically for a few more years.  New information is constantly being published that will have other statistical figures.  Physicians must read these articles critically in order to interpret the data correctly and incorporate the information correctly into their practice.  In other words, statistics provide a guideline only.  They help to guide treatment decisions.  They are NOT meant to be applied to individuals.