Parp inhibitors as maintenance treatment in platinum sensitive recurrent ovarian cancer: An updated meta-analysis of randomized clinical trials according to BRCA mutational status

ObjectiveThis meta-analysis investigated the effectiveness of PARP inhibitors (PARPis) as maintenance treatment in platinum sensitive recurrent ovarian cancer (ROC), stratifying results based on BRCA mutational status into five different categories: whole population, germ-line BRCA mutated patients, somatic BRCA mutated patients, HRD patients and wild type population.MethodsPubMed, Medline, Scopus, EMBASE and clinicaltrials.gov, as well as meeting proceedings were searched for eligible studies that described RCTs testing the efficacy of PARPis as maintenance treatment in platinum sensitive ROC. Data were extracted independently and analysed using RevMan statistical software version 5.3. Primary end-point was progression free survival (PFS).ResultsThe analysis confirmed the positive effect of PARPis in patients with platinum sensitive ROC in case of germinal or somatic BRCA mutations. Specifically, HR for PFS was 0.26, 95% CI 0.21–0.31, p < 0.00001 for the mutation of BRCA gene and 0.24, 95%, CI 0.12–0.48, p < 0.0001 for the somatic alteration. In addition, in the HRD population, studies that analysed the efficacy of PARPis  reported a PFS improvement with HR 0.34, 95% CI 0.26–0.43, p < 0.00001. Finally, our analysis confirms the role of these drugs in prolonging PFS in the whole population with HR 0.36, 95% CI 0.32–0.42, p < 0.00001, although to a lesser extent, with a significant improvement even in wild type cancers with HR 0.49, 95%, CI 0.41–0.59, p < 0.00001).ConclusionsPARPis are effective regardless of BRCA mutational status. Future investigations are necessary to explore the use of different PARPis as monotherapy, comparing them among each other in terms of efficacy and toxicity, and exploring their potential re-use.     

Survival outcomes of metastatic breast cancer patients by germline BRCA1/2 status in a large multicenter real-world database

The outcomes and best treatment strategies for germline BRCA1/2 mutation (gBRCAm) carriers with metastatic breast cancer (MBC) remain uncertain. We compared the overall survival and the first line progression free survival (PFS1) of patients with a gBRCAm identified at initiation of first-line treatment with those of BRCA wild-type (WT) and not-tested (NT) individuals in the ESME real-world database of MBC patients between 2008 and 2016 (NCT03275311). Among the 20 624 eligible patients, 325 had a gBRCAm, 1138 were WT and 19 161 NT. Compared with WT, gBRCAm carriers were younger, and had more aggressive diseases. At a median follow-up of 50.5 months, median OS was 30.6 (95%CI: 21.9-34.3), 35.8 (95%CI: 32.2-37.8) and 39.3 months (95% CI: 38.3-40.3) in the gBRCAm, WT and NT subgroups, respectively. Median PFS1 was 7.9 (95%CI: 6.6-9.3), 7.8 (95%CI: 7.3-8.5) and 9.7 months (95%CI, 9.5-10.0). In the multivariable analysis conducted in the whole cohort, gBRCAm status had however no independent prognostic impact on OS and PFS1. Though, in the triple-negative subgroup, gBRCAm patients had better OS and PFS1 (HR vs WT = 0.76; 95%CI: 0.60-0.97; P = .027 and 0.69; 95% CI: 0.55-0.86; P = .001, respectively). In contrast, in patients with HR+/HER2 negative cancers, PFS1 appeared significantly and OS non significantly lower for gBRCAm carriers (PFS1: HR vs WT = 1.23; 95%CI: 1.03-1.46; P = .024; OS:HR = 1.22, 95% CI: 0.97-1.52, P = .089). In conclusion, gBRCA1/2 status appears to have divergent survival effects in MBC according to IHC subtype.     

Factors influencing ovulation and the risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

The role of the lifetime number of ovulatory cycles has not been evaluated in the context of BRCA‐associated ovarian cancer. Thus, we conducted a matched case–control study to evaluate the relationship between the cumulative number of ovulatory cycles (and contributing components) and risk of developing ovarian cancer in BRCA mutation carriers (1,329 cases and 5,267 controls). Information regarding reproductive and hormonal factors was collected from a routinely administered questionnaire. Conditional logistic regression was used to evaluate all associations. We observed a 45% reduction in the risk of developing ovarian cancer among women in the lowest vs. highest quartile of ovulatory cycles (OR = 0.55; 95% CI 0.41–0.75, p = 0.0001). Breastfeeding for more than 12 months was associated with a 38% (95% CI 0.48–0.79) and 50% (95% CI 0.29–0.84) reduction in risk among BRCA1 and BRCA2 mutation carriers, respectively. For oral contraceptive use, maximum benefit was seen with five or more years of use among BRCA1 mutation carriers (OR = 0.50; 95% CI 0.40–0.63) and three or more years for BRCA2 mutation carriers (OR = 0.42; 95% CI 0.22–0.83). Increasing parity was associated with a significant inverse trend among BRCA1 (OR = 0.87; 95% CI 0.79–0.96; p‐trend = 0.005) but not BRCA2 mutation carriers (OR 0.98; 95% CI 0.81–1.19; p‐trend = 0.85). A later age at menopause was associated with an increased risk in women with a BRCA1 mutation (OR trend = 1.18; 95% CI 1.03–1.35; p = 0.02). These findings support an important role of breastfeeding and oral contraceptive use for the primary prevention of ovarian cancer among women carrying BRCA mutations.     

Reconsidering the mechanisms of action of PARP inhibitors based on clinical outcomes

PARP inhibitors (PARPis) were initially developed as DNA repair inhibitors that inhibit the catalytic activity of PARP1 and PARP2 and are expected to induce synthetic lethality in BRCA‐ or homologous recombination (HR)‐deficient tumors. However, the clinical indications for PARPis are not necessarily limited to BRCA mutations or HR deficiency; BRCA wild‐type and HR‐proficient cancers can also derive some benefit from PARPis. These facts are interpretable by an additional primary antitumor mechanism of PARPis named PARP trapping, resulting from the stabilization of PARP‐DNA complexes. Favorable response to platinum derivatives (cisplatin and carboplatin) in preceding treatment is used as a clinical biomarker for some PARPis, implying that sensitivity factors for platinum derivatives and PARPis are mainly common. Such common sensitivity factors include not only HR defects (HRD) but also additional factors. One of them is Schlafen 11 (SLFN11), a putative DNA/RNA helicase, that sensitizes cancer cells to a broad type of DNA‐damaging agents, including platinum and topoisomerase inhibitors. Mechanistically, SLFN11 induces a lethal replication block in response to replication stress (ie, DNA damage). As SLFN11 acts upon replication stress, trapping PARPis can activate SLFN11. Preclinical models show the importance of SLFN11 in PARPi sensitivity. However, the relevance of SLFN11 in PARPi response is less evident in clinical data compared with the significance of SLFN11 for platinum sensitivity. In this review, we consider the reasons for variable indications of PARPis resulting from clinical outcomes and review the mechanisms of action for PARPis as anticancer agents.     

Survival analysis of carboplatin added to an anthracycline/taxane-based neoadjuvant chemotherapy and HRD score as predictor of response—final results from GeparSixto

BackgroundIn the neoadjuvant GeparSixto study, adding carboplatin to taxane- and anthracycline-based chemotherapy improved pathological complete response (pCR) rates in patients with triple-negative breast cancer (TNBC). Here, we present survival data and the potential prognostic and predictive role of homologous recombination deficiency (HRD).Patients and methodsPatients were randomized to paclitaxel plus nonpegylated liposomal doxorubicin (Myocet®) (PM) or PM plus carboplatin (PMCb). The secondary study end points disease-free survival (DFS) and overall survival (OS) were analyzed. Median follow-up was 47.3 months. HRD was among the exploratory analyses in GeparSixto and was successfully measured in formalin-fixed, paraffin-embedded tumor samples of 193/315 (61.3%) participants with TNBC. Homologous recombination (HR) deficiency was defined as HRD score ≥42 and/or presence of tumor BRCA mutations (tmBRCA).ResultsA significantly better DFS (hazard ratio 0.56, 95% CI 0.34–0.93; P = 0.022) was observed in patients with TNBC when treated with PMCb. The improvement of OS with PMCb was not statistically significant. Additional carboplatin did not improve DFS or OS in patients with HER2-positive tumors. HR deficiency was detected in 136 (70.5%) of 193 triple-negative tumors, of which 82 (60.3%) showed high HRD score without tmBRCA. HR deficiency independently predicted pCR (ypT0 ypN0) [odds ratio (OR) 2.60, 95% CI 1.26–5.37, P = 0.008]. Adding carboplatin to PM significantly increased the pCR rate from 33.9% to 63.5% in HR deficient tumors (P = 0.001), but only marginally in HR nondeficient tumors (from 20.0% to 29.6%, P = 0.540; test for interaction P = 0.327). pCR rates with carboplatin were also higher (63.2%) than without carboplatin (31.7%; OR 3.69, 1.46–9.37, P = 0.005) in patients with high HRD score but no tmBRCA. DFS rates were improved with addition of carboplatin, both in HR nondeficient (hazard ratio 0.44, 0.17–1.17, P = 0.086) and HR deficient tumors (hazard ratio 0.49, 0.23–1.04, P = 0.059).ConclusionsThe addition of carboplatin to neoadjuvant PM improved DFS significantly in TNBC. Long-term survival analyses support the neoadjuvant use of carboplatin in TNBC. HR deficiency in TNBC and HRD score in non-tmBRCA TNBC are predictors of response. HRD does not predict for carboplatin benefit.     

Panitumumab plus trifluridine/tipiracil as anti-EGFR rechallenge therapy in patients with refractory RAS wild-type metastatic colorectal cancer: Overall survival and subgroup analysis of the randomized phase II VELO trial

The randomized phase II VELO trial showed that the addition of panitumumab to trifluridine/tipiracil significantly improves progression-free survival (PFS) as compared to trifluridine/tipiracil in third-line therapy in patients with refractory RAS wild-type (WT) metastatic colorectal cancer (mCRC). With longer follow-up, final overall survival results and posttreatment subgroup analysis are presented. Sixty-two patients with refractory RAS WT mCRC were randomly assigned to receive, as third-line therapy, trifluridine/tipiracil alone (arm A) or in combination with panitumumab (arm B). Primary endpoint was PFS; secondary endpoints included overall survival (OS) and overall response rate (ORR). Median OS was 13.1 months (95% CI 9.5-16.7) in arm A compared to 11.6 months (95% CI 6.3-17.0) in arm B (HR: 0.96, 95% CI 0.54-1.71, P = .9). To evaluate the impact of subsequent lines of treatment, subgroup analysis was performed for the 24/30 patients in arm A, that received fourth-line therapy after disease progression. Median PFS was 4.1 months (95% CI 1.44-6.83) for 17 patients treated with anti-EGFR rechallenge as compared to 3.0 months (95% CI 1.61-4.31) for seven patients that received other therapies (HR: 0.29, 95% CI 0.10-0.85, P = .024). Median OS from the start of fourth-line treatment was 13.6 months (95% CI 7.2-20), and 5.1 months (95% CI 1.8-8.3) for patients treated with anti-EGFR rechallenge vs other therapies, respectively (HR: 0.30, 95% CI 0.11-0.81, P = .019). Final results of the VELO trial support the role of anti-EGFR rechallenge in the continuum of care of patients with RAS/BRAF WT mCRC.     

Homologous recombination inquiry through ovarian malignancy investigations: JGOG3025 Study

The Cancer Genome Atlas (TCGA) network has clarified that ~50% of high-grade serous ovarian cancers show homologous recombination deficiency (HRD). However, the frequency of HRD in Japanese patients with ovarian cancer remains unclear. We aimed to identify the frequency of HR-associated gene mutations in Japanese patients with ovarian cancer. The JGOG3025 study is a multicenter collaborative prospective observational study involving 65 study sites throughout Japan. We recruited 996 patients who were clinically diagnosed with ovarian cancer before surgery from March 2017 to March 2019, and 701 patients were eligible according to the criteria. We used frozen tumor tissues to extract DNA and performed next-generation sequencing for 51 targeted genes (including 29 HR-associated genes) in 701 ovarian cancers (298 high-grade serous cases, 189 clear cell cases, 135 endometrioid cases, 12 mucinous cases, 3 low-grade serous cases, and 64 others). HRD was defined as positive when at least one HR-associated gene was mutated. The frequencies of HRD and tumor BRCA1/2 mutations were 45.2% (317/701) and 18.5% (130/701), respectively, in the full analysis set. Next, we performed multivariate Cox proportional hazards regression analysis for progression-free survival (PFS) and overall survival (OS). Advanced-stage ovarian cancer patients with HRD had adjusted hazard ratios of 0.72 (95% CI, 0.55–0.94) and 0.57 (95% CI, 0.38–0.86) for PFS and OS, respectively, compared with those without HRD (p = 0.016 and 0.007). Our study demonstrated that mutations in HR-associated genes were associated with prognosis. Further studies are needed to investigate the prognostic impact of each HR-associated gene in ovarian cancer.     

Impact of homologous recombination deficiency biomarkers on outcomes in patients with triple-negative breast cancer treated with adjuvant doxorubicin and cyclophosphamide (SWOG S9313)

BackgroundHomologous recombination deficiency (HRD)-causing alterations have been reported in triple-negative breast cancer (TNBC). We hypothesized that TNBCs with HRD alterations might be more sensitive to anthracycline plus cyclophosphamide-based chemotherapy and report on HRD status and BRCA1 promoter methylation (PM) as prognostic markers in TNBC patients treated with adjuvant doxorubicin (A) and cyclophosphamide (C) in SWOG9313.Patients and methodsIn total, 425 TNBC patients were identified from S9313. HRD score, tumor BRCA1/2 sequencing, and BRCA1 PM were carried out on DNA isolated from formalin-fixed paraffin-embedded tissue. Positive HRD status was defined as either a deleterious tumor BRCA1/2 (tBRCA) mutation or a pre-defined HRD score ≥42. Markers were tested for prognostic value on disease-free survival (DFS) and overall survival (OS) using Cox regression models adjusted for treatment assignment and nodal status.ResultsHRD status was determined in 89% (379/425) of cases. Of these, 67% were HRD positive (27% with tBRCA mutation, 40% tBRCA-negative but HRD score ≥42). HRD-positive status was associated with a better DFS [hazard ratio (HR) 0.72; 95% confidence interval (CI) 0.51–1.00; P = 0.049] and non-significant trend toward better OS (HR = 0.71; 95% CI 0.48–1.03; P = 0.073). High HRD score (≥42) in tBRCA-negative patients (n = 274) was also associated with better DFS (HR = 0.64; 95% CI 0.43–0.94; P = 0.023) and OS (HR = 0.65; 95% CI 0.42–1.00; P = 0.049). BRCA1 PM was evaluated successfully in 82% (348/425) and detected in 32% of cases. The DFS HR for BRCA1 PM was similar to that for HRD but did not reach statistical significance (HR = 0.79; 95% CI 0.54–1.17; P = 0.25).ConclusionsHRD positivity was observed in two-thirds of TNBC patients receiving adjuvant AC and was associated with better DFS. HRD status may identify TNBC patients who receive greater benefit from AC-based chemotherapy and should be evaluated further in prospective studies.Clinical Trials NumberInt0137 (The trial pre-dates Clinicaltrial.Gov website establishment)     

Dual targeted therapy with pyrotinib and trastuzumab for HER2-positive advanced colorectal cancer: A phase 2 trial

This trial was initiated to evaluate the efficacy and safety of pyrotinib in combination with trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive recurrent/metastatic colorectal cancer (CRC). In this single-arm, open-label, multicenter, phase 2 trial patients with HER2-positive recurrent/metastatic CRC were enrolled and received oral pyrotinib 400 mg once a day plus intravenous trastuzumab 8 mg/kg loading dose followed by 6 mg/kg once every 3 weeks. The primary endpoint was the objective response rate (ORR). Disease control rate (DCR), progression-free survival (PFS), duration of response, and safety were assessed as secondary endpoints. From December 2019 to October 2021, a total of 20 patients were enrolled and 18 of them were evaluable for response. All patients were B-rapidly accelerated fibrosarcoma (BRAF) wild type. Four patients achieved partial response, with an ORR of 22.2% (4/18, 95% confidence interval [CI] 6.4–47.6) and DCR of 61.1% (11/18, 95% CI 35.8–82.7), while the ORR and DCR were 33.3% (4/12, 95% CI 13.8–60.9) and 83.3% (10/12, 95% CI 51.6–97.9), respectively, in RAS wild-type patients. At the time of cut-off day, median follow-up was 10.7 months (range 3.8–13.8). The median PFS was 3.4 months (95% CI 1.8–4.3) in the overall population and 4.3 months (95% CI 3.2–8.5) in the RAS wild-type group. The most common adverse event of grade ≥3 was diarrhea (13/20, 65.0%). Pyrotinib combined with trastuzumab showed promising antitumor activity and a manageable safety profile in patients with RAS/BRAF wild-type HER2-positive advanced CRC.     

An open-label, single-arm, phase 2 trial of panitumumab plus FOLFIRI as second-line therapy in patients with metastatic colorectal cancer

Background

This prospective analysis evaluated the effect of tumor KRAS status on efficacy of second-line panitumumab plus folinic acid/5-fluorouracil/irinotecan (FOLFIRI).

Methods

This phase 2, open-label, single-arm study enrolled patients with unresectable, measurable metastatic colorectal cancer (mCRC) after failure of first-line treatment with oxaliplatin-based chemotherapy plus bevacizumab. Patients received panitumumab 6 mg/kg plus FOLFIRI every 2 weeks until disease progression or intolerability. Tumor assessments per Response Evaluation Criteria in Solid Tumors (RECIST) were performed by the investigators every 8 weeks from weeks 8-32 and every 12 weeks thereafter. KRAS status was determined by real-time polymerase chain reaction (PCR) on DNA extracted from fixed tumor sections. Efficacy endpoints included objective response rate, progression-free survival (PFS), and overall survival (OS). Safety endpoints included incidence of adverse events (AEs). Endpoints were evaluated by tumor KRAS status.

Results

Of 116 patients enrolled, 109 patients with known tumor KRAS status received treatment; 59% had wild-type KRAS, and 41% had mutant KRAS. Fifteen patients (23%) with wild-type KRAS and 7 patients (16%) with mutant KRAS had a complete or partial response to treatment. Median PFS was 26 weeks (95% CI, 19-33 weeks) and 19 weeks (95% CI, 12-25 weeks) in the wild-type KRAS and mutant KRAS strata, respectively. Median OS was 50 weeks (95% CI, 39-76 weeks) and 31 weeks (95% CI, 23-47 weeks) in wild-type KRAS and mutant KRAS strata, respectively. Skin-related toxicities (86% of all patients) and diarrhea (74%) were the most common AEs.

Conclusion

Panitumumab plus FOLFIRI numerically improved objective response rate, PFS, and OS in favor of patients with wild-type KRAS tumors. The safety profile was consistent with panitumumab plus FOLFIRI trials in similar patient populations.     

Selumetinib with and without erlotinib in KRAS mutant and KRAS wild-type advanced nonsmall-cell lung cancer

BackgroundKRAS mutations in NSCLC are associated with a lack of response to epidermal growth factor receptor inhibitors. Selumetinib (AZD6244; ARRY-142886) is an oral selective MEK kinase inhibitor of the Ras/Raf/MEK/ERK pathway.Patients and methodsAdvanced nonsmall-cell lung cancer (NSCLC) patients failing one to two prior regimens underwent KRAS profiling. KRAS wild-type patients were randomized to erlotinib (150 mg daily) or a combination of selumetinib (150 mg daily) with erlotinib (100 mg daily). KRAS mutant patients were randomized to selumetinib (75 mg b.i.d.) or the combination. The primary end points were progression-free survival (PFS) for the KRAS wild-type cohort and objective response rate (ORR) for the KRAS mutant cohort. Biomarker studies of ERK phosphorylation and immune subsets were carried out.ResultsFrom March 2010 to May 2013, 89 patients were screened; 41 KRAS mutant and 38 KRAS wild-type patients were enrolled. Median PFS in the KRAS wild-type arm was 2.4 months [95% confidence interval (CI) 1.3–3.7] for erlotinib alone and 2.1 months (95% CI 1.8–5.1) for the combination. The ORR in the KRAS mutant group was 0% (95% CI 0.0% to 33.6%) for selumetinib alone and 10% (95% CI 2.1% to 26.3%) for the combination. Combination therapy resulted in increased toxicities, requiring dose reductions (56%) and discontinuation (8%). Programmed cell death-1 expression on regulatory T cells (Tregs), Tim-3 on CD8+ T cells and Th17 levels were associated with PFS and overall survival in patients receiving selumetinib.ConclusionsThis study failed to show improvement in ORR or PFS with combination therapy of selumetinib and erlotinib over monotherapy in KRAS mutant and KRAS wild-type advanced NSCLC. The association of immune subsets and immune checkpoint receptor expression with selumetinib may warrant further studies.     

One-carbon metabolism biomarkers and risk of urothelial cell carcinoma in the European prospective investigation into cancer and nutrition

Published associations between dietary folate and bladder cancer risk are inconsistent. Biomarkers may provide more accurate measures of nutrient status. This nested case–control analysis within the European Prospective Investigation into Cancer and Nutrition (EPIC) investigated associations between pre-diagnostic serum folate, homocysteine, vitamins B6 and B12 and the risk of urothelial cell carcinomas of the bladder (UCC). A total of 824 patients with newly diagnosed UCC were matched with 824 cohort members. Serum folate, homocysteine, and vitamins B6 and B12 were measured. Odds ratios (OR) and 95% confidence intervals (CI) for total, aggressive, and non-aggressive UCC were estimated using conditional logistic regression with adjustment for smoking status, smoking duration and intensity, and other potential confounders. Additionally, statistical interaction with smoking status was assessed. A halving in serum folate concentrations was moderately associated with risk of UCC (OR: 1.18; 95% CI: 0.98–1.43), in particular aggressive UCC (OR: 1.34; 95% CI: 1.02–1.75; p-heterogeneity = 0.19). Compared to never smokers in the highest quartile of folate concentrations, this association seemed only apparent among current smokers in the lowest quartile of folate concentrations (OR: 6.26; 95% CI: 3.62–10.81, p-interaction = 0.07). Dietary folate was not associated with aggressive UCC (OR: 1.26; 95% CI: 0.81–1.95; p-heterogeneity = 0.14). No association was observed between serum homocysteine, vitamins B6 and B12 and risk of UCC. This study suggests that lower serum folate concentrations are associated with increased UCC risk, in particular aggressive UCC. Residual confounding by smoking cannot be ruled out and these findings require confirmation in future studies with multiple measurements.     

Bevacizumab plus chemotherapy continued beyond first progression in patients with metastatic colorectal cancer previously treated with bevacizumab plus chemotherapy: ML18147 study KRAS subgroup findings

BackgroundML18147 evaluated continued bevacizumab with second-line chemotherapy for patients with metastatic colorectal cancer (mCRC) progressing after the standard first-line bevacizumab-containing therapy.Patients and methodsEvaluating outcomes according to tumor Kirsten rat sarcoma virus oncogene (KRAS) status was an exploratory analysis. KRAS data were collected from local laboratories (using their established methods) and/or from a central laboratory (mutation-specific Scorpion amplification-refractory mutation system). No adjustment was made for multiplicity; analyses were not powered to detect statistically significant differences.ResultsOf 820 patients, 616 (75%) had unambiguous KRAS data; 316 (51%) had KRAS wild-type tumors and 300 (49%) had mutant KRAS tumors. The median progression-free survival (PFS) was 6.4 months for bevacizumab plus chemotherapy and 4.5 months for chemotherapy [P < 0.0001; HR = 0.61; 95% confidence interval (CI): 0.49–0.77] for wild-type KRAS and 5.5 and 4.1 months, respectively (P = 0.0027; HR = 0.70; 95% CI: 0.56–0.89) for mutant KRAS. The median overall survival (OS) was 15.4 and 11.1 months, respectively (P = 0.0052; HR = 0.69; 95% CI: 0.53–0.90) for wild-type KRAS and 10.4 versus 10.0 months, respectively (P = 0.4969; HR = 0.92; 95% CI: 0.71–1.18) for mutant KRAS. In both analyses, no treatment interaction by KRAS status was observed (PFS, P = 0.4436; OS, P = 0.1266).ConclusionsBevacizumab beyond first progression represents an option for patients with mCRC treated with bevacizumab plus standard first-line chemotherapy, independent of KRAS status.     

Japanese nationwide observational multicenter study of tumor BRCA1/2 variant testing in advanced ovarian cancer

The association between germline BRCA1 and BRCA2 pathogenic variants (mutations: gBRCAm) and ovarian cancer risk is well established. Germline testing alone cannot detect somatic BRCA1/2 pathogenic variants (sBRCAm), which is calculated based on the proportion of tumor BRCAm (tBRCAm) from tumor samples and gBRCAm. Homologous recombination deficiency (HRD) results mainly from genetic/epigenetic alterations in homologous recombination repair-related genes and can be evaluated by genomic instability status. In Japan, the prevalence of tBRCAm, sBRCAm, and HRD remains unclear. This multicenter, cross-sectional, observational study, CHaRacterIzing the croSs-secTional approach to invEstigate the prevaLence of tissue BRCA1/2 mutations in newLy diagnosEd advanced ovarian cancer patients (CHRISTELLE), evaluated the prevalence of tBRCAm, sBRCAm, and HRD in tumor specimens from newly diagnosed patients with ovarian cancer who underwent gBRCA testing. Of the 205 patients analyzed, 26.8% had a tBRCAm, including tBRCA1m (17.6%) and tBRCA2m (9.3%). The overall prevalence of tBRCAm, gBRCAm, sBRCAm, and HRD-positive status was 26.8%, 21.5%, 6.3%, and 60.0%, respectively. The calculated sBRCAm/tBRCAm ratio was 23.6% (13/55), and the prevalence of gBRCA variant of uncertain significance was 3.9%. These results suggest gBRCA testing alone cannot clearly identify the best course of treatment, highlighting the importance of sBRCA testing in Japan. The present results also suggest that testing for tBRCA and HRD should be encouraged in advanced ovarian cancer patients to drive precision medicine.     

Efficacy and safety of osimertinib in treating EGFR-mutated advanced NSCLC: A meta-analysis

Osimertinib is the only Food and Drug Administration-approved third-generation epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitor (TKI). A meta-analysis was performed to aggregate the mixed results of published clinical trials to assess the efficacy and safety of osimertinib. A systematic search of the PubMed, Web of Science, and Cochrane Library electronic databases was performed to identify eligible literature. The primary endpoints were overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and adverse events (AEs). A total of 3,086 advanced nonsmall cell lung cancer (NSCLC) patients from 11 studies have been identified. The aggregate efficacy parameters for treatment-naïve patients with EGFR-TKI-sensitizing mutations are as follows: ORR 79% (95% CI 75–84%), DCR 97% (95% CI 95–99%), 6-month PFS 83% (95% CI 80–87%), and 12-month PFS 64% (95% CI 59–69%). The aggregate efficacy parameters for advanced NSCLC harboring T790M mutations after earlier-generation EGFR-TKI therapy are as follows: ORR 58% (95% CI 46–71%), DCR 80% (95% CI 63–98%), 6-month PFS 63% (95% CI 58–69%), and 12-month PFS 32% (95% CI 17–47%). EGFR-TKI-naïve patients with EGFR-positive mutations tend to have longer median PFS than EGFR-TKI-pretreated counterparts (19.17 vs. 10.58 months). The most common AEs were diarrhea and rash, of which the pooled incidences were 44 and 42%, respectively. Generally, osimertinib is a favorable treatment option for previously treated T790M mutation-positive advanced NSCLC as well as a preferable therapy for untreated EGFR mutation-positive advanced NSCLC. Additionally, osimertinib is well tolerated by most patients.     

Which is false: Oxaliplatin or fluoropyrimidine? An analysis of patients with KRAS wild‐type metastatic colorectal cancer treated with first‐line epidermal growth factor receptor monoclonal antibody

This meta‐analysis was performed to determine whether the addition of monoclonal antibodies (mAbs) of epidermal growth factor receptor (EGFR) to oxaliplatin‐based chemotherapy treatment improves efficacy in KRAS wild‐type metastatic colorectal cancer (mCRC), and whether infusional 5‐fluorouracil (5‐FU) and oxaliplatin is a preferred combination for EGFR mAbs. Oxaliplatin (including treatment), EGFR mAbs, first‐line treatment, KRAS wild‐type, and mCRC were used as key words. The PRIME, OPUS, COIN, and NORDIC VII trials were identified by two independent authors. Time‐to‐event outcomes of overall survival (OS) and progression‐free survival (PFS) were analyzed using HRs (hazard ratios) with fixed effect, and response rate (RR) using odd ratios (OR) with fixed effect. A total of 1767 patients who were KRAS wild‐type were included in this meta‐analysis, with 866 patients in the mAbs and chemotherapy combination group and 901 patients in the chemotherapy alone group. The addition of mAbs to oxaliplatin‐based chemotherapy in patients with KRAS wild‐type mCRC as first‐line treatment resulted in significant improvements in PFS (HR = 0.88; 95% confidence interval (CI), 0.79–0.99; P = 0.03) and response rate (RR) (OR = 1.38; 95% CI, 1.14–1.66; P = 0.009) compared with chemotherapy alone, but the difference in OS was not significant (HR = 0.96; 95% CI, 0.85–1.08; P = 0.48). However, the differences in OS and PFS were not significant when mAbs were added to bolus 5‐FU or capecitabine‐based regimens compared with chemotherapy alone, whereas PFS improved with an infusional 5‐FU and oxaliplatin combination (P = 0.06; PFS, HR = 0.76; 95% CI, 0.65–0.86; P = 0.0002), and even OS was marginally significant, which was consistent with the subgroup analysis of cetuximab and panitumumab. EGFR mAbs combined with oxaliplatin and an infusional 5‐FU regimen was associated with significantly improved RR, PFS and OS as first‐line treatment in KRAS wild‐type mCRC.     

The European Medicines Agency Approval of Axitinib (Inlyta) for the Treatment of Advanced Renal Cell Carcinoma After Failure of Prior Treatment With Sunitinib or a Cytokine: Summary of the Scientific Assessment of the Committee for Medicinal Products for Human Use

Axitinib is a tyrosine kinase inhibitor of vascular endothelial growth factor receptor 1 (VEGFR‐1), VEGFR‐2, and VEGFR‐3. Based on the positive opinion from the European Medicines Agency (EMA), a marketing authorization valid throughout the European Union (EU) was issued for the treatment of advanced renal cell carcinoma (RCC) after failure of prior treatment with sunitinib or a cytokine. The demonstration of clinical benefit for axitinib was based on a phase III, randomized, open‐label, multicenter study of axitinib compared with sorafenib in patients with advanced RCC after failure of a prior systemic first‐line regimen containing one or more of the following agents: sunitinib, bevacizumab plus interferon‐α, temsirolimus, or cytokines. In the primary analysis, a 2‐month increase in median progression‐free survival (PFS) was observed for axitinib compared with sorafenib (hazard ratio [HR]: 0.665; 95% confidence interval [CI]: 0.544–0.812; p < .0001). In the subgroup of patients with a prior cytokine‐containing regimen, the increase in median PFS associated with axitinib was 5.4 months (updated analysis, HR: 0.519; 95% CI: 0.375–0.720; p < .0001). In the subgroup of patients with prior sunitinib treatment, the increase in median PFS was 1.4 months (updated analysis, HR: 0.736; 95% CI: 0.578–0.937; p = .0063). The analysis of overall survival showed no statistically significant survival benefit of axitinib over sorafenib in patients previously treated with cytokine‐containing regimens (HR: 0.813; 95% CI: 0.556–1.191) or sunitinib (HR: 0.997; 95% CI: 0.782–1.270). The most common treatment‐related adverse events associated with axitinib included diarrhea, hypertension, fatigue, nausea, decreased appetite, dysphonia, and palmar‐plantar erythrodysesthesia. Most of these events were mild or moderate in severity. This paper summarizes the scientific review of the application leading to approval in the EU. The detailed scientific assessment report and product information, including the summary of product characteristics, are available on the EMA website ( http://www.ema.europa.eu ).     

Relation of early tumor shrinkage (ETS) observed in first‐line treatment to efficacy parameters of subsequent treatment in FIRE‐3 (AIOKRK0306)

We explored the association of early tumor shrinkage (ETS) and non‐ETS with efficacy of first‐line and consecutive second‐line treatment in patients with KRAS wild‐type metastatic colorectal cancer treated in FIRE‐3. Assessment of tumor shrinkage was based on the sum of longest diameters of target lesions, evaluated after 6 weeks of treatment. Shrinkage was classified as ETS (shrinkage by ≥ 20%), mETS (shrinkage by 0 to <20%), mPD (minor progression >0 to <20%) and PD (progression ≥20%). Overall survival (OS) was 33.2 (95% CI 28.0–38.4) months in ETS patients, while non‐ETS was associated with less favorable outcome (mETS 24.0 (95% CI 21.2–26.9) months, mPD 19.0 (95% CI 13.0–25.0) months, PD 12.8 (95% CI 11.1–14.5) months). Differences in PFS of first‐line therapy were less pronounced. ETS subgroups defined in first‐line therapy also correlated with efficacy of second‐line therapy. Progression‐free survival in second‐line (PFS2nd) was 6.5 months (5.8–7.2) for ETS, and was 5.6 (95% CI 4.7–6.5) months for mETS, 4.9 (95% CI 3.7–6.1) months for mPD and 3.3 (95% CI 2.3–4.3) months for PD. PFS of first‐line and PFS2nd showed a linear correlation (Bravais–Pearson coefficient: 0.16, p = 0.006). While ETS is associated with the most favorable outcome, non‐ETS represents a heterogeneous subgroup with distinct characteristics of less favorable initial tumor response to treatment. This is the first analysis to demonstrate that early tumor response observed during first‐line FOLFIRI‐based therapy may also relate to efficacy of second‐line treatment. Early response parameters may serve as stratification factors in trials recruiting pretreated patients.     

Risk of metachronous breast cancer after BRCA mutation–associated ovarian cancer

BACKGROUND:

This study sought to estimate the risk of breast cancer (BC) after a diagnosis of ovarian cancer (OC) associated with mutation of the BRCA1/2 (breast cancer, early onset) genes (BRCA‐OC).

METHODS:

The Memorial Sloan‐Kettering Cancer Center and the University of Pennsylvania, clinical genetics databases were searched to identify women with BRCA‐OC who participated in genetic testing and follow‐up studies from 1995 to 2009. The primary objective was to determine the risk of developing BC after BRCA‐OC. Overall survival (OS) and BC‐free survival (BCFS) were determined by the Kaplan‐Meier method; patients were censored at the time of last follow‐up.

RESULTS:

A total of 164 patients had BRCA‐OC (115 with BRCA1; 49 with BRCA2). Of these 164 patients, 152 developed OC prior to BRCA testing (median time to testing, 2.4 years [0.01‐55 years]). Median follow‐up from OC for those not developing BC was 5.8 years (0.25‐55.6 years). There were 46 deaths, but none were due to BC. The 5‐ and 10‐year OS were 85% (95% confidence interval [CI] = 0.78, 0.90) and 68% (95% CI = 0.59, 0.76), respectively. There were 18 metachronous BC diagnoses. The 5‐ and 10‐year BCFS were 97% (95% CI = 0.92, 0.99) and 91% (95% CI = 0.82, 0.95), respectively. A subset of 64 women were tested either before or within 12 months of BRCA‐OC. In this pseudo‐incident subset, 5‐ and 10‐ year OS was 71% (95% CI = 0.53, 0.83) and 62% (95% CI = 0.44, 0.75), respectively, and 5‐ and 10‐year BCFS were 100% and 87% (95% CI = 0.56, 0.96), respectively.

CONCLUSIONS:

OS was dominated by OC deaths. Metachronous BC risk was lower than reported for unaffected BRCA mutation carriers. These results support nonsurgical management of BC risk in women with BRCA‐OC. Cancer 2013. © 2012 American Cancer Society.     

Recapitulating the clinical scenario of BRCA‐associated pancreatic cancer in pre‐clinical models

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies. BRCA‐associated PDAC comprises a clinically relevant subtype. A portion of these patients are highly susceptible to DNA damaging therapeutics, however, responses are heterogeneous and clinical resistance evolves. We have developed unique patient‐derived xenograft (PDX) models from metastatic lesions of germline BRCA‐mutated patients obtained at distinct time points; before treatment and at progression. Thus, closely mimicking clinical scenarios, to further investigate treatment naïve and resistant patients. DNA was isolated from six BRCA‐mutated PDXs and classified by whole‐genome sequencing to stable‐genome or homologous recombination deficient (HRD)‐genome. The sensitivity to DNA‐damaging agents was evaluated in vivo in three BRCA‐associated PDAC PDXs models: (1) HRD‐genome naïve to treatments; (2) stable‐genome naïve to treatment; (3) HRD‐genome resistant to treatment. Correlation between disease course at tissue acquisition and response to PARP inhibitor (PARPi)/platinum was demonstrated in PDXs in vivo. Only the HRD‐genome PDX, naïve to treatment, was sensitive to PARP inhibitor/cisplatin treatments. Our results demonstrate heterogeneous responses to DNA damaging agents/PARPi in BRCA‐associated PDX thus reflecting the wide clinical spectrum. An HRD‐genome PDX generated from a naïve to treatment biopsy was sensitive to platinum/PARPi whereas no benefit was observed in treating a HRD‐genome PDXs generated from a patient that had acquired resistance nor stable‐genome PDXs.