title: Breast cancer following curative chemotherapy for non-Hodgkin's lymphoma and the effect of drug resistance proteins to the final outcome. A retrospective study.
abstract: OBJECTIVE
  To investigate the overall survival (OS) of patients developing breast cancer (BC) after curative chemotherapy for non-Hodgkin's lymphoma (NHL) and to evaluate the possible effect on the patients' outcome of the expression of drug resistance-related proteins (P-glycoprotein-Pgp, multidrug resistance-associated protein-MRP, and multidrug resistance-related vault lung resistance protein-LRP) in BC issue.
  
  
  METHODS
  
  
  
  METHODS
  25 female patients (median age 60 years, range 37-70) who developed BC after chemotherapy for high/intermediate grade B-cell NHL, treated with CHOP and achieving complete remission (CR). This group was further subdivided in subgroups A and B, according to the time interval between NHL and BC development (</=24 and > 24 months, respectively). A matched-pair group of de novo BC patients formed the control group. BC tissue was immuno-histochemically stained for Pgp, MRP and LRP.
  
  
  RESULTS
  The median interval between NHL diagnosis and BC development was 26 months (range 9-49). In both groups 14 patients had tumor grade II; 16 were negative for steroid receptors; 17 overexpressed c-erbB-2; 14 were stage IIIA/B, and 11 stage IV. CMF or CNF (mitoxantrone instead of doxorubicin) were given for BC. Early progression was noticed in all study group patients for which second-line chemotherapy was instituted. There was a better response for stage IV patients in the control versus the study group (p=0.07). More prolonged OS was demonstrate for patients with stage III in the control group (median 51 months) and in subgroup B (median 47 months) than in subgroup A (median 16 months; p=0.00012), as well as for patients with advanced disease (p=0.0045). Development of BC < 24 months after NHL resulted in reduced OS (p=0.017). No difference was noticed in the expression of drug resistance proteins between the study and control group or between subgroups A and B.
  
  
  CONCLUSIONS
  BC developing shortly after a CR to NHL is an aggressive disease variant with minimal potential for response to conventional chemotherapy. Analysis of Pgp, MRP and LRP failed to demonstrate significant difference between the study and control group, although indications exist that drug resistance mechanisms might be part of the aggressive disease phenotype, contributing to the poor outcome.
authors.affiliation: Departments of Pathophysiology-Medical Oncology Unit, "Laikon" University General Hospital, Athens University School of Medicine, Athens, Greece.
authors.forename: N
authors.initials: N
authors.lastname: Tsavaris
authors.forename: C
authors.initials: C
authors.lastname: Kosmas
authors.forename: N
authors.initials: N
authors.lastname: Kavantzas
authors.forename: A
authors.initials: A
authors.lastname: Lazaris
authors.forename: E
authors.initials: E
authors.lastname: Skopelitis
authors.forename: A
authors.initials: A
authors.lastname: Dimitrakopoulos
authors.forename: M P
authors.initials: MP
authors.lastname: Siakantaris
authors.forename: E
authors.initials: E
authors.lastname: Papalambros
authors.forename: N
authors.initials: N
authors.lastname: Diamantis
authors.forename: E
authors.initials: E
authors.lastname: Patsouris
authors.forename: G A
authors.initials: GA
authors.lastname: Pangalis