Prognostic significance of factors affecting disease free interval and overall survival for Stage II breast cancer in Greece. A multivariate cohort study.
BACKGROUND
Univariate analysis evaluates the impact of a prognostic factor on survival rates, either disease free (DFI) or overall (OS). Since many of the factors are interrelated, it is difficult to predict the prognosis of an individual patient. Multivariate analysis is therefore required in order to allow factors act together thus ending in the best possible combined predicting result.


METHODS
A step-up procedure (Cox's Proportional Hazards Regression model) was used to include various prognostic parameters, relating to patients themselves, to the pathology of their tumours and to the treatment schedule followed. Two hundred and sixty-nine Stage II breast cancer Greek patients, treated from 1981 until 1991 and with a median 12-year of follow-up are studied.


RESULTS
Five factors were found to be significant for patients DFI. In order of relevant importance, these were the number of infiltrated nodes, tumour size, postoperative radiotherapy, adjuvant chemotherapy and patients age. Regarding patients OS, tumour size, number of positive nodes, patients' age at entry and ER/PR status were the most important ones.


CONCLUSIONS
Our long-term (12-year), single institution, single area results, suggest that, the prognostic factors for patients DFI and OS are the same with those of series from Europe and USA. Additionally, they remain unchanged after long-term follow-up, compared to a previously reported short-term national-wide study from this country.
Breast Unit, Department of Surgery, University of Patras Medical School, Patras University Hospital, Rion-Patras, Greece.
G
G
Vorgias
D
D
Koukouras
V
V
Paleogianni
E
E
Tzoracoeleftherakis
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality* / Q000473:pathology; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006115:Greece / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011379:Prognosis; D015996:Survival Rate