Our study provides more precise data on the incidence of endocrine dysfunctions among patients receiving ICI regimens. Patients on combination therapy are at increased risk of thyroid dysfunction and hypophysitis.

Purpose: BRCA1/2-mutated and some sporadic triple-negative breast cancers (TNBC) have DNA repair defects and are sensitive to DNA-damaging therapeutics. Recently, three independent DNA-based measures of genomic instability were developed on the basis of loss of heterozygosity (LOH), telomeric allelic imbalance (TAI), and large-scale state transitions (LST).Experimental Design: We assessed a combined homologous recombination deficiency (HRD) score, an unweighted sum of LOH, TAI, and LST scores, in three neoadjuvant TNBC trials of platinum-containing therapy. We then tested the association of HR deficiency, defined as HRD score !42 or BRCA1/2 mutation, with response to platinum-based therapy.

Triple negative breast cancer (TNBC) is a heterogeneous and clinically aggressive disease for which there is no targeted therapy1-3. BET bromodomain inhibitors, which have shown efficacy in several models of cancer4-6, have not been evaluated in TNBC. These inhibitors displace BET bromodomain proteins such as BRD4 from chromatin by competing with their acetyllysine recognition modules, leading to inhibition of oncogenic transcriptional programs7-9. Here we report the preferential sensitivity of TNBCs to BET bromodomain inhibition in vitro and in vivo, establishing a rationale for clinical investigation and further motivation to understand mechanisms of resistance. In paired cell lines selected for acquired resistance to BET inhibition from previously sensitive TNBCs, we failed to identify gatekeeper mutations, new driver events or drug pump activation. BET-resistant TNBC cells remain dependent on wild-type BRD4, which supports transcription and cell proliferation in a bromodomain-independent manner. Proteomic studies of resistant TNBC identify strong association with MED1 and hyper-phosphorylation of BRD4 attributable to decreased activity of PP2A, identified here as a principal BRD4 serine phosphatase. Together, these studies provide a rationale for BET inhibition in TNBC and present mechanism-based combination strategies to anticipate clinical drug resistance.

BACKGROUND No single standard treatment exists for patients with small, node-negative, human epidermal growth factor receptor type 2 (HER2)–positive breast cancers, because most of these patients have been ineligible for the pivotal trials of adjuvant trastuzumab. METHODS We performed an uncontrolled, single-group, multicenter, investigator-initiated study of adjuvant paclitaxel and trastuzumab in 406 patients with tumors measuring up to 3 cm in greatest dimension. Patients received weekly treatment with paclitaxel and trastuzumab for 12 weeks, followed by 9 months of trastuzumab monotherapy. The primary end point was survival free from invasive disease. RESULTS The median follow-up period was 4.0 years. The 3-year rate of survival free from invasive disease was 98.7% (95% confidence interval [CI], 97.6 to 99.8). Among the 12 relapses seen, 2 were due to distant metastatic breast cancer. Excluding contra-lateral HER2-negative breast cancers and nonbreast cancers, 7 disease-specific events were noted. A total of 13 patients (3.2%; 95% CI, 1.7 to 5.4) reported at least one episode of grade 3 neuropathy, and 2 had symptomatic congestive heart failure (0.5%; 95% CI, 0.1 to 1.8), both of whom had normalization of the left ventricular ejection fraction after discontinuation of trastuzumab. A total of 13 patients had significant asymptomatic declines in ejection fraction (3.2%; 95% CI, 1.7 to 5.4), as defined by the study, but 11 of these patients were able to resume trastuzumab therapy after a brief interruption. CONCLUSIONS Among women with predominantly stage I HER2-positive breast cancer, treatment with adjuvant paclitaxel plus trastuzumab was associated with a risk of early recurrence of about 2%; 6% of patients withdrew from the study because of protocol-specified adverse events. (Funded by Genentech; ClinicalTrials.gov number, NCT00542451.)

Purpose Dual human epidermal growth factor receptor 2 (HER2) targeting can increase pathologic complete response rates (pCRs) to neoadjuvant therapy and improve progression-free survival in metastatic disease. CALGB 40601 examined the impact of dual HER2 blockade consisting of trastuzumab and lapatinib added to paclitaxel, considering tumor and microenvironment molecular features. Patients and Methods Patients with stage II to III HER2-positive breast cancer underwent tumor biopsy followed by random assignment to paclitaxel plus trastuzumab alone (TH) or with the addition of lapatinib (THL) for 16 weeks before surgery. An investigational arm of paclitaxel plus lapatinib (TL) was closed early. The primary end point was pCR in the breast; correlative end points focused on molecular features identified by gene expression–based assays. Results Among 305 randomly assigned patients (THL, n = 118; TH, n = 120; TL, n = 67), the pCR rate was 56% (95% CI, 47% to 65%) with THL and 46% (95% CI, 37% to 55%) with TH (P = .13), with no effect of dual therapy in the hormone receptor–positive subset but a significant increase in pCR with dual therapy in those with hormone receptor–negative disease (P = .01). The tumors were molecularly heterogeneous by gene expression analysis using mRNA sequencing (mRNAseq). pCR rates significantly differed by intrinsic subtype (HER2 enriched, 70%; luminal A, 34%; luminal B, 36%; P < .001). In multivariable analysis treatment arm, intrinsic subtype, HER2 amplicon gene expression, p53 mutation signature, and immune cell signatures were independently associated with pCR. Post-treatment residual disease was largely luminal A (69%). Conclusion pCR to dual HER2-targeted therapy was not significantly higher than single HER2 targeting. Tissue analysis demonstrated a high degree of intertumoral heterogeneity with respect to both tumor genomics and tumor microenvironment that significantly affected pCR rates. These factors should be considered when interpreting and designing trials in HER2-positive disease.

The hallmark of human cancer is heterogeneity, reflecting the complexity and variability of the vast array of somatic mutations acquired during oncogenesis. An ability to dissect this heterogeneity, to identify subgroups that represent common mechanisms of disease, will be critical to understanding the complexities of genetic alterations and to provide a framework to develop rational therapeutic strategies. Here, we describe a classification scheme for human breast cancer making use of patterns of pathway activity to build on previous subtype characterizations using intrinsic gene expression signatures, to provide a functional interpretation of the gene expression data that can be linked to therapeutic options. We show that the identified subgroups provide a robust mechanism for classifying independent samples, identifying tumors that share patterns of pathway activity and exhibit similar clinical and biological properties, including distinct patterns of chromosomal alterations that were not evident in the heterogeneous total population of tumors. We propose that this classification scheme provides a basis for understanding the complex mechanisms of oncogenesis that give rise to these tumors and to identify rational opportunities for combination therapies.

Background Olaparib is an oral poly(ADP-ribose) polymerase inhibitor and cediranib is an oral anti-angiogenic with activity against VEGFR-1, 2, and 3. Both agents have antitumor activity in women with recurrent ovarian cancer, and the combination of these agents was active and had manageable toxicities in a Phase 1 trial. We asked whether the combination of cediranib and olaparib could improve progression-free survival compared to olaparib monotherapy in women with recurrent platinum-sensitive ovarian cancer. Methods We conducted a randomized, open-label, phase 2 study to evaluate the activity of olaparib monotherapy compared with combination cediranib and olaparib in women with ovarian cancer with measurable platinum-sensitive, relapsed, high-grade serous or endometrioid disease or those with deleterious germline BRCA1/2 mutations (gBRCAm). Patients were randomized using permuted blocks within stratum defined by gBRCA status and prior anti-angiogenic therapy to receive olaparib capsules 400mg twice daily or the combination at the recommended phase 2 dose of cediranib 30mg daily and olaparib capsules 200mg twice daily. The primary endpoint was progression-free survival (PFS) analyzed under intention to treat. The trial is registered with ClinicalTrials.gov, NCT01116648. The Phase 2 portion of the trial reported here is no longer accruing patients. Findings Forty-six of 90 randomized patients received olaparib alone, and 44 received cediranib/olaparib. Median PFS was significantly longer with cediranib/olaparib (17.7 vs. 9.0 mos, HR 0.42; p = 0.005). Grade 3 and 4 adverse events were more common with cediranib/olaparib, including fatigue (12 vs. 5), diarrhea (10 vs. 0), and hypertension (18 vs. 0). Subset analysis within stratum defined by BRCA1/2 status demonstrated activity of cediranib/olaparib in both gBRCAm and gBRCAwt/u (wild-type/unknown) patients. Significant improvement in PFS occurred in gBRCAwt/u women receiving cediranib/olaparib (16.5 vs. 5.7 mos, p = 0.008) with a smaller trend towards increased PFS in gBRCAm patients (19.4 vs. 16.5 mos, p = 0.16). Interpretation The combination of cediranib and olaparib significantly extended PFS by 8.7 months compared to olaparib alone in recurrent platinum-sensitive ovarian cancer. The activity observed with this oral combinaton in both gBRCAmt and gBRCAwt/u patients is encouraging and should be further explored as a potential alternative to cytotoxic chemotherapy. Given the side effect profile, such explorations should include assessments on quality of life and patient-reported outcomes to understand the effects of an ongoing oral regimen to that of intermittent chemotherapy.

http://www.bios.unc.edu/~fwright/SAFE.