Disease-free survival and prognostic significance of metastatic lymph node ratio in T1-T2 N positive breast cancer patients. A population registry-based study in a European country.
BACKGROUND
The ratio of positive lymph nodes between the total number of harvested lymph nodes (metastatic lymph node ratio, MLNR) has been proposed as an alternative to the total number of lymph nodes alone in predicting outcomes for patients with breast cancer. Because there can be differences between European and non-European populations, the authors present the first study analyzing MLNR influence over disease-free survival (DFS) by using a population-based cancer registry in a European country.


METHODS
Data from 441 patients with T1-2 N1-3 breast cancer included in the Castellon Cancer Registry (Comunidad Valenciana, Spain) were used. Cumulative DFS was determined using the Kaplan-Meier method, with univariate comparisons between groups through the log-rank test. The Cox proportional hazards model was used for multivariate analysis.


RESULTS
At univariate analysis, factors influencing the 10-year DFS rate were tumor size, conservative or nonconservative surgery, histologic grade, histologic type, radiotherapy, tamoxifen, estrogen and progesterone receptor status, p53 status, total number of positive lymph nodes, and MLNR. At multivariate analysis, tumor size, MLNR, and progesterone receptor status were revealed to be independent prognostic factors; the metastatic lymph node ratio was the most notably independent factor (hazard ratio 1.02, 5.21, and 0.61, respectively).


CONCLUSIONS
MLNR is a stronger prognostic factor for recurrence than the total number of positive lymph nodes in T1-T2 N1-3 breast cancer.
Martinez-Ramos
David
D
Department of General and Digestive Surgery, Castellon General Hospital, Avda Benicassim s/n. 12004, Castellon, Spain. davidmartinez@comcas.es
Escrig-Sos
Javier
J
Alcalde-Sanchez
Miguel
M
Torrella-Ramos
Ana
A
Salvador-Sanchis
Jose Luis
JL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000473:pathology*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012042:Registries; D013030:Spain / Q000453:epidemiology; D015996:Survival Rate