Chemotherapy prolongs survival for isolated local or regional recurrence of breast cancer the CALOR trial (Chemotherapy as Adjuvant for Locally Recurrent breast cancer; IBCSG 27-02, NSABP B-37, BIG 1-02)

SUMMARY: Approximately 5% to 15% of all breast cancer patients present with local and/or regional recurrences. The role of adjuvant chemotherapy after resection of an isolated recurrence of breast cancer is unknown. To address this, in the CALOR trial, 162 patients with recurrent tumors underwent surgery and were then randomized to receive either four cycles of a multidrug chemotherapy regimen of investigator’s choice (n=85) or observation (n=77). The median age was 56 years. The treatment groups were well balanced and 68% and 58% of patients in the observation and treatment arms respectively received prior adjuvant chemotherapy. The median time to recurrence was 5 years in the treatment group and 6 years in the observation group. The primary end point was disease free survival (DFS). The 5-year DFS rate for the chemotherapy group and observation group was 69% vs 57% respectively. This translated into a relative risk reduction of 41% (hazard ratio [HR], 0.59; P = 0.045). The 5-year overall survival rate between the chemotherapy group and observation group was 88% vs 76% with a 59% reduction in the relative risk for death for patients treated with chemotherapy (HR, 0.41; P = 0.02). In patients with ER-negative tumors, the 5-year DFS was 67% in the treatment arm versus 35% in the control group (HR = 0.32; P = 0.007). This data supports the role of chemotherapy for patients with completely resected isolated locoregional recurrences of breast cancer. Aebi S, Gelber S, Láng I, et al. Presented at: CTRC-AACR San Antonio Breast Cancer Symposium, 2012. Abstract S3-2.

PERJETA® (Pertuzumab)

The FDA on June 8, 2012 approved PERJETA® injection for use in combination with HERCEPTIN® (Trastuzumab and docetaxel for the treatment of patients with HER2-positive metastatic breast cancer who have not received prior anti-HER2 therapy or chemotherapy for metastatic disease. PERJETA® is a product of Genentech, Inc.

AFINITOR® (Everolimus tablets)

The FDA on July 20, 2012 approved AFINITOR® for the treatment of postmenopausal women with advanced hormone receptor-positive, HER2-negative breast cancer in combination with exemestane, after failure of treatment with FEMARA® (Letrozole) or ARIMIDEX® (Anastrozole). AFINITOR® is a product of Novartis Pharmaceuticals Corporation.

Primary results from EMILIA, a phase III study of trastuzumab emtansine (T-DM1) versus capecitabine (X) and lapatinib (L) in HER2-positive locally advanced or metastatic breast cancer (MBC) previously treated with trastuzumab (T) and a taxane

SUMMARY:The HER or erbB family of receptors consist of HER 1,HER 2,HER 3 and HER 4. Overexpression of HER 2 in breast cancer has been associated with higher risk for relapse as well as overall survival. Trastuzumab is a humanized monoclonal antibody targeting HER 2. It binds to the extracellular domain of the receptor and blocks the downstream cell signaling pathways. Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate (ADC) comprised of the antibody trastuzumab and the chemotherapy agent DM1 linked together and inhibits HER2 signaling and destroys the HER2-positive tumor cells by delivering the chemotherapy agent DM1 directly inside the tumor cells. The EMILIA trial is a phase III study in which 978 patients with HER2-positive locally advanced or metastatic breast cancer who had previously received treatment with HERCEPTIN® (Trastuzumab) and a taxane chemotherapy, were enrolled. Patient received either trastuzumab emtansine (T-DM1) or XELODA® (Capecitabine) and TYKERB® (Lapatinib) doublet. The primary endpoints were Progression Free Survival (PFS), Overall Survival (OS) and safety. Patients receiving T-DM1 had an improved PFS compared to XELODA® and TYKERB® (9.6 months vs 6.4 months, HR=0.65, P <0.0001). A final OS analysis will be available at a later date. Blackwell KL, Miles D, Gianni L, et al. J Clin Oncol 30, 2012 (suppl; abstr LBA1)

Everolimus in Postmenopausal Hormone-Receptor–Positive Advanced Breast Cancer

SUMMARY: The mechanism of resistance to hormonal therapy in breast cancer is thought to be related to the activation of mTOR pathway, independent of ER (estrogen receptor) signalling pathway. To test this hypothesis, the authors in this study (BOLERO-2) decided to combine mTOR inhibition with estrogen deprivation. In a phase III trial, patients with ER positive, advanced breast cancer, who had recurred or progressed on prior therapy with nonsteroidal aromatase inhibitors (anastrozole or letrazole), were randomized in a 2:1 ratio to either receive everolimus (mTOR inhibitor) and exemestane (steroidal aromatase inhibitor) or exemestane and placebo. The primary end point of Progression Free Survival was significant with 10.6 months for mTOR inhibitor plus exemestane vs 4.1 months for exemestane plus placebo, according to central review (hazard ratio, 0.36; P<0.001). This new paradigm of adding everolimus to hormonal therapy should change the way we manage patients with advanced breast cancer, who are resistant to hormonal therapy alone. Baselga J, Campone M, Piccart M, et al. N Engl J Med 2012; 366:520-529

Risk Factors for Breast Cancer for Women Aged 40 to 49 Years

SUMMARY: There is presently no clear consensus regarding breast cancer screening for women in their 40’s. The risk/benefit ratio of screening mammography has not been properly defined in this age group. In this review, Nelson and colleagues identified the risk factors for breast cancer and concluded that there is a 2 fold increase in the risk for breast cancer in women 40-49 years of age, who have dense breast tissue and first degree relatives with breast cancer. This meta analysis has identified a subset of patients in their 40’s who would benefit from screening mammography. Nelson HD, Zakher B, Cantor A, et al. Ann Intern Med. 2012;156:635-648

Pertuzumab plus Trastuzumab plus Docetaxel for Metastatic Breast Cancer

SUMMARY: The CLEOPATRA trial is a phase III trial in which 808 HER positive metastatic breast cancer patients, for their first line treatment, were randomized to either HERCEPTIN® plus Docetaxel or the above two drug combination given along with PERJETA® (Pertuzumab). PERJETA® is a recombinant humanized monoclonal antibody that binds to the HER2 dimerization domain and prevents the dimerization of HER2 with other HER receptors ie. HER3, HER1 and HER4. The addition of PERJETA® to the combination of HERCEPTIN® and Docetaxel significantly prolonged progression-free survival compared to HERCEPTIN® plus Docetaxel alone (18.5 months vs 12.4 months, P<0.001). This benefit was seen without increase in cardiotoxicity. It appears that PERJETA® complements HERCEPTIN® in targeting HER-2 receptor. Baselga J, Cortés J, Kim S, et al. N Engl J Med 2012; 366:109-119

CLEOPATRA Trial in Breast Cancer

In this Phase III trial involving first line treatment of patients with HER-2 positive metastatic breast cancer,  the addition of Pertuzumab (an anti-HER-2 humanized monoclonal antibody that inhibits receptor dimerization) to a combination of Trastuzumab and Docetaxel significantly prolonged progression-free survival, without increase in cardiotoxicity when compared to Trastuzumab and Docetaxel alone. It appears that Pertuzumab complements Trastuzumab in targeting HER-2 receptor.

These findings from the CLEOPATRA trial have demonstrated that comprehensive  HER-2 blockade may result in improved outcomes for patients with breast cancer  over expressing HER-2.

The original article was published in the January 2012  issue of the NEJM.

Exemestane for Breast-Cancer Prevention in Postmenopausal Women

SUMMARY: Breast cancer is the second most common cause of death in the United States. Presently two Selective Estrogen Receptor Modulators (SERM’s), tamoxifen and raloxifene are approved by the FDA, for the primary prevention of breast cancer. Tamoxifen has been associated with increased risk of venous thromboembolism and endometrial cancers. Raloxifene can also be associated with venous thromboembolism but has not been associated with endometrial cancers. Exemestane is an irreversible, steroidal aromatase inactivator. This agent was evaluated in a randomized, placebo controlled, double blind study, to reduce the risk of invasive breast cancer in postmenopausal women, considered to be at moderately increased risk of developing breast cancer. Risk factors included age over 60 years, Gail five year risk score greater than 1.66% and prior atypical ductal/ lobular hyperplasia, LCIS, or DCIS with mastectomy. At a median follow up of 3 years, exemestane reduced the relative incidence of invasive breast cancers by 65% compared to placebo and this benefit was accomplished without serious toxicities and with minimal changes in quality of life. This is the first aromatase inhibitor/inactivator to demonstrate proven efficacy in breast cancer prevention, in a randomized clinical trial. N Engl J Med 2011; 364:2381-2391

Breast Cancer Prevention

Exemestane is an aromatase inactivator presently approved by the FDA for the treatment of breast cancer. This drug was studied in a large randomized clinical trial for the prevention of breast cancer. The results of this study were published in the June 23 issue of the NEJM. Exemestane reduced the relative incidence of invasive breast cancer by 65%, in postmenopausal women with moderate risk of developing breast cancer. The benefit with this drug was accomplished without any significant serious toxicities.

Breast Cancer is the second most common cause of cancer death in the United States. This new addition will be additional ammunition, in the fight against breast cancer