Importance of metabolic changes induced by chemotherapy on prognosis of early-stage breast cancer patients: a review of potential mechanisms.

Weight variation has been reported as a side effect of chemotherapy treatment in early breast cancer patients and has been identified as a factor of poor prognosis. Causes of weight variation during chemotherapy and mechanisms involved in the poor prognosis have been little studied. Here is reviewed the current knowledge about the main causes and mechanisms involved in body weight change. Special emphasis is placed on factors associated with weight variation which could potentially be involved in the risk of relapse in breast cancer survivors. In recent decades, some studies have investigated the causes of weight variation by studying energy balance of breast cancer patients during chemotherapy. Weight gain or loss may be the consequence of energy imbalance through different factors linked with chemotherapy, such as poor treatment tolerance, decreased muscle mass and function, or hormonal alterations. This results in body composition modifications in favour of fat gain and/or lean body mass loss. Increased adipose tissue, especially in the abdominal region, could induce metabolic disturbances such as insulin resistance, through various pathways involving adipokines. These molecules have growth properties and could therefore play a role in cancer relapse. Understanding such mechanisms is key to developing preventive strategies for improving the prognosis of early-stage breast cancer patients.

Prognostic value of initial tumor parameters after metastatic relapse.

Classical prognostic factors of breast cancer are correlated to disease-free survival and overall survival (OS); their precise role is less known on metastatic disease. A total of 511 breast cancer patients without initial metastasis were treated. OS was divided in time to distant recurrence and metastatic survival (MS). Age, Scarff-Bloom-Richardson (SBR) grade, hormone receptor, axillary node involvement, and Nottingham prognostic index predicted MS in univariate analysis. Multivariate analysis retained age, SBR grade, and axillary lymph node involvement as significant independent prognostic factors. Interactions are still present between initial parameters and MS. The clinician has to take into account for treatment choice.

Late lines of treatment benefit survival in metastatic breast cancer in current practice?

Metastatic breast cancer is mostly incurable. Progressively overall survival (OS) has improved but few authors have studied treatment globally versus for each line and demonstrated the interest of chemotherapy (CT) after the third line. We selected recent patients treated during the "taxane/anti-aromatase era" for each line given. 529 received CT and 383 hormonotherapy. OS was assessed; from the date of first metastasis and from Day 1 of each CT line. Median OS was 34.1 months; 226 patients received >3 lines of CT with a steady median OS for late lines, 11.4 months per line (range 10.4-12.6). Clinical benefit after the third line of CT was obtained for 29.2-36.6% of patients. CT lasted 11.7 months "on"versus 20.6 months "off" CT. These results may support the use of more than 3 CT lines; each line can contribute to a longer survival.