Can pathologic complete response (pCR) be used as a surrogate marker of survival after neoadjuvant therapy for breast cancer?

Breast cancer is heterogeneous in clinical, morphological, immunohistochemical and biological features, as reflected by several different prognostic subgroups. Neoadjuvant approaches are currently used for the "in vivo" efficacy assessment of treatments. Pathological complete response (pCR) has been reported as a reliable predictive factor of survival in that setting. However, pCR remains a subject of controversy in terms of definition and its evaluation methods. In addition, its predictive value for patient outcome in various breast cancer biological subtypes has been under debate. In this review, we will present the existing definitions of pCR, the impact of its evaluation methods on its rate and the assessment of its predictive value for patient outcome in the molecular subtypes of breast cancer (luminal A and B, Triple Negative and HER2-positive).

Is it important to adapt neoadjuvant chemotherapy to the visible clinical response? An open randomized phase II study comparing response-guided and standard treatments in HER2-negative operable breast cancer.

BACKGROUND: Neoadjuvant treatment provides a unique opportunity to evaluate individual tumor sensitivity. This study evaluated whether a response-guided strategy could improve clinical outcome compared with a standard treatment. METHODS: Overall, 264 previously untreated stage II-III operable breast cancer patients were randomized to receive either standard treatment (arm A, n = 131), consisting of fluorouracil, epirubicin, and cyclophosphamide (FEC100: 500, 100, and 500 mg/m(2), respectively, for 3 cycles) followed by docetaxel (100 mg/m(2) for 3 cycles), or adapted treatment (arm B, n = 133), beginning with 2 cycles of FEC100 and switching to docetaxel if tumor size decreased by <30% after 2 cycles or <50% after 4 cycles of FEC100 (ultrasound assessments according to World Health Organization criteria). Otherwise, FEC100 was given for six cycles before surgery. Intent-to-treat analysis was performed. RESULTS: Similar results were observed for clinical response (objective response was 54% vs 56%, p = .18), breast conservation surgery (BCS; 67% vs 68%, p = .97), and pathological complete response rate (Chevallier classification: 14% vs 11%, p = .68; Statloff classification: 16% vs 13%, p = .82) between arms A and B. Similar toxicities were observed, even with unbalanced numbers of FEC100 and docetaxel courses. CONCLUSION: Adapted and standard treatments had similar results in terms of tumor response, BCS rate, and tolerability. Further survival outcome data are expected.

Prognostic factors in operable breast cancer treated with neoadjuvant chemotherapy: towards a quantification of residual disease.

OBJECTIVE: Neoadjuvant chemotherapy (NACT) allows for a more frequent use of breast-conservative surgery; it is also an in vivo model of individual tumor sensitivity which permits to determine new prognostic factors to personalize the therapeutic approach. METHODS: Between 2000 and 2012, 318 patients with primary invasive breast cancer were treated with a median of 6 cycles of NACT; they received either an anthracycline-based FEC 100 protocol (31.1%), or anthracyclines + taxanes (53.5%), with trastuzumab if indicated (15.4%). RESULTS: After a median follow-up of 44.2 months, the pathological complete response rate according to the classification of Chevallier et al. [Am J Clin Oncol 1993;16:223-228] was 19.3%, and overall (OS) and disease-free survival (DFS) at 10 years were 60.2 and 69.6%, respectively. Univariate analyses demonstrated that the Residual Disease in Breast and Nodes (RDBN) index was the most significant prognostic factor for OS (p = 0.0082) and DFS (p = 0.0022), and multivariate analyses mainly revealed that the residual tumor size, residual involved node number and post-chemotherapy Scarff-Bloom-Richardson (SBR) grading were the most significant prognostic factors. CONCLUSIONS: In a cohort of patients who were all homogeneously treated with some of the most common drugs for breast cancer, we demonstrate that NACT may provide additional prognostic factors and confirm the RDBN index. As this index allows for the prediction of survival with different breast cancer subtypes, we suggest that it should be calculated routinely to help clinicians to select patients who need adjuvant treatments.

[Poor prognostic value of weight change during chemotherapy in non-metastatic breast cancer patients: causes, mechanisms involved and preventive strategies]. / Valeur péjorative des variations de poids en cours de chimiothérapie dans le cancer du sein non métastatique : causes, mécanismes impliqués et stratégies préventives.

Numerous studies have demonstrated that a significant change in weight during chemotherapy treatment was a factor of poor prognosis in early breast cancer women. However, the causes and mechanisms involved in this phenomenon are not fully known. This review summarizes current knowledge about the causes of energy imbalance during chemotherapy treatment and the mechanisms that have been proposed as responsible for the increased risk of relapse and death in this population. Current preventive strategies focus on physical activity programs but also on the use of metformin during and after chemotherapy.