The paradox of triple negative breast cancer: novel approaches to treatment

Breast cancer that lacks expression of estrogen/progesterone receptors and overexpression of the human epidermal growth factor receptor2 (HER2), i.e. triple-negative breast cancer (TNBC), is not amenable to current targeted therapies and carries a poor prognosis. This review discusses the natural history of TNBC and published literature in the relevant treatment landscape, with a focus on newer therapies. Compared with other subtypes of breast cancer, TN tumors have higher response rates to neoadjuvant chemotherapy; however, this advantage is not clearly translated into the metastatic setting and has not improved these patients' overall survival. Numerous cytotoxic and targeted strategies have demonstrated efficacy or are under investigation. Strategies showing promise in this difficult-to-treat group of patients include cytotoxic therapy with platinum-containing agents, ixabepilone, and novel targeted approaches such as poly(ADP-ribose) polymerase inhibitors.

Management options in triple-negative breast cancer

Notorious for its poor prognosis and aggressive nature, triple-negative breast cancer (TNBC) is a heterogeneous disease entity. The nature of its biological specificity, which is similar to basal-like cancers, tumors arising in BRCA1 mutation carriers, and claudin-low cancers, is currently being explored in hopes of finding the targets for novel biologics and chemotherapeutic agents. In this review, we aim to give a broad overview of the disease's nomenclature and epidemiology, as well as the basic mechanisms of emerging targeted therapies and their performance in clinical trials to date.

The interaction of body mass index and race in predicting biochemical failure after radical prostatectomy

STUDY TYPE

Therapy (case series).

LEVEL OF EVIDENCE

4

OBJECTIVE

To examine the interaction of body mass index (BMI) and race in predicting biochemical failure (BCF) after radical prostatectomy (RP). The relative contribution of BMI and race to BCF after RP has not been well characterized.

PATIENTS AND METHODS

From 1988 to 2008, 969 white and black men underwent RP and BMI data were available. In all, 168 (17.3%) were black and 801 (82.7%) were white men. BCF was defined as a post-surgery PSA level≥0.2 ng/mL on ≥2 measurements. Cox regression methods were used to model the relationship between race, BMI and BCF.

RESULTS

The 969 men had a mean age of 59.8±7.2 years. There was no significant difference in BMI between black and white men (P=0.32). The 5-year disease-free survival for black obese men was the lowest at 48%, compared with non-obese black (73%), obese white (82%) and non-obese white men (83%, P<0.001). BMI did not have a significant impact on BCF. In a multivariate analysis, black race remained an independent predictor of BCF [hazard ratio (HR)=1.76, P=0.01]. BMI does not affect the risk of BCF in black men differently than white men (P value for interaction 0.93).

CONCLUSIONS

Black race is an independent predictor of biochemical failure after adjusting for pathological factors. The impact of BMI on BCF did not vary among different races. These findings suggest that elevated BMI does not affect the BCF rates of black men more than in other races, and that other factors may influence the racial variability in disease-free survival and BCF risk.

Triple-negative breast cancer--current status and future directions

Triple-negative breast cancer (TNBC) is defined by a lack of expression of both estrogen and progesterone receptor as well as human epidermal growth factor receptor 2. It is characterized by distinct molecular, histological and clinical features including a particularly unfavorable prognosis despite increased sensitivity to standard cytotoxic chemotherapy regimens. TNBC is highly though not completely concordant with various definitions of basal-like breast cancer (BLBC) defined by high-throughput gene expression analyses. The lack in complete concordance may in part be explained by both BLBC and TNBC comprising entities that in themselves are heterogeneous. Numerous efforts are currently being undertaken to improve prognosis for patients with TNBC. They comprise both optimization of choice and scheduling of common cytotoxic agents (i.e. addition of platinum salts or dose intensification strategies) and introduction of novel agents (i.e. poly-ADP-ribose-polymerase-1 inhibitors, agents targeting the epidermal growth factor receptor, multityrosine kinase inhibitors or antiangiogenic agents).