Outcomes of a Phase II Study of Intraperitoneal Paclitaxel plus Systemic Capecitabine and Oxaliplatin (XELOX) for Gastric Cancer with Peritoneal Metastases.

BACKGROUND: Adding intraperitoneal paclitaxel (IP-PTX) to paclitaxel/5-fluoropyrimidine has shown promising results in patients with gastric cancer peritoneal metastases (GCPM) but has not been studied with standard-of-care platinum/fluoropyrimidine combinations. Our goal to was evaluate IP-PTX with capecitabine/oxaliplatin (XELOX) in GCPM. METHODS: Forty-four patients with GCPM received IP PTX (40 mg/m2, Days 1, 8), oral capecitabine (1000 mg/m2 twice daily, Days 1-14) and intravenous oxaliplatin (100 mg/m2, Day 1) in 21-day cycles. Patients with synchronous GCPM underwent conversion surgery if they had good response after chemotherapy, conversion to negative cytology, no extraperitoneal metastasis, and no peritoneal disease during surgery. The primary endpoint was overall survival and secondary endpoints were progression-free survival and safety. Outcomes from the trial were compared against a matched cohort of 39 GCPM patients who received systemic chemotherapy (SC) comprising platinum/fluoropyrimidine. RESULTS: The median OS for the IP and SC groups was 14.6 and 10.6 months (hazard ratio [HR] 0.44; 95% confidence interval [CI], 0.26-0.74; p = 0.002). The median PFS for the IP and SC group was 9.5 and 4.4 months respectively (HR 0.39; 95% CI 0.25-0.66; p < 0.001). Patients in the SC group were younger (IP vs. SC, 61 vs. 56 years, p = 0.021) and had better performance status (ECOG 0, IP vs. SC, 47.7% vs. 76.9%, p = 0.007) compared with the IP cohort. In IP group, conversion surgery was performed in 36.1% (13/36) of patients, with a median OS of 24.2 (95% CI 13.1-35.3) months and 1-year OS of 84.6%. CONCLUSIONS: IP PTX with XELOX is a promising treatment option for GCPM patients. In patients with good response, conversion surgery was feasible with favourable outcomes.

Phase II study of trifluridine/tipiracil in metastatic breast cancers with or without prior exposure to fluoropyrimidines.

BACKGROUND: Fluoropyrimidines are commonly used in the treatment of metastatic breast cancer (MBC), and trifluridine/tipiracil (FTD/TPI) has shown activity in patients with colorectal and gastric cancers despite prior exposure to fluoropyrimidines. We investigate the role of FTD/TPI in patients with MBC with or without prior fluoropyridines in a single-arm phase II study. METHODS: Patients with MBC were enroled first into a run-in dose confirmation phase, followed by two parallel cohorts including patients with (Cohort A) and without (Cohort B) prior exposure to fluoropyrimidines, where they were treated with FTD/TPI. Primary objectives for each cohort included determination of progression-free survival (PFS), and secondary objectives included determination of objective response rates (ORR), safety, and tolerability. RESULTS: Seventy-four patients (42 Cohort A, 32 Cohort B) were enroled, all of whom were evaluable for toxicity and survival, with 72 evaluable for response. Median PFS was 5.7 months (95% confidence interval 3.8-8.3) and 9.4 months (95% CI 5.5-14.0) respectively in Cohorts A and B. Responses were observed regardless of prior exposure to fluoropyrimidines, with ORR of 19.5% (95% CI 8.8-34.9) and 16.1% (95% CI 5.5-33.7) in Cohorts A and B, and 6-month clinical benefit rates of 56.1% (95% CI 39.7-71.5) and 61.3% (95% CI 42.2-78.2) respectively. The safety profile was consistent with known toxicities of FTD/TPI, including neutropenia, fatigue, nausea, and anorexia, mitigated with dose modifications. CONCLUSION: FTD/TPI showed promising antitumour activity with manageable toxicity and is a clinically valid option in patients with MBC.

Serial Tumor Molecular Profiling of Newly Diagnosed HER2-Negative Breast Cancers During Chemotherapy in Combination with Angiogenesis Inhibitors.

BACKGROUND: Breast cancers are heterogeneous with variable clinical courses and treatment responses. OBJECTIVE: We sought to evaluate dynamic changes in the molecular landscape of HER2-negative tumors treated with chemotherapy and anti-angiogenic agents. PATIENTS AND METHODS: Newly diagnosed HER2-negative breast cancer patients received low-dose sunitinib or bevacizumab prior to four 2-weekly cycles of dose-dense doxorubicin and cyclophosphamide. Tumor biopsies were obtained at baseline, after 2 weeks and after 8 weeks of chemotherapy. Next-generation sequencing was performed to assess for single nucleotide variants (SNVs) and copy number alterations (CNAs) of 440 cancer-related genes (ACTOnco®). Observed genomic changes were correlated with the Miller-Payne histological response to treatment. RESULTS: Thirty-four patients received sunitinib and 18 received bevacizumab. In total, 77% were hormone receptor positive (HER2-/HR+) and 23% were triple negative breast cancers (TNBC). New therapy-induced mutations were infrequent, occurring only in 13%, and appeared early after a single cycle of treatment. Seventy-two percent developed changes in the variant allele frequency (VAF) of pathogenic SNVs; the majority (51%) of these changes occurred early at 2 weeks and were sustained for 8 weeks. Changes in VAF of SNVs were most commonly seen in the PI3K/mTOR/AKT pathway; 13% developed changes in pathogenic mutations, which potentially confer sensitivity to PIK3CA inhibitors. Tumors with poor Miller-Payne response to treatment were less likely to experience changes in VAF of SNVs compared with those with good response (50% [7/14] vs 15% [4/24] had no changes observed at any timepoint, p = 0.029). CONCLUSIONS: Serial molecular profiling identifies early therapy-induced genomic alterations, which may guide future selection of targeted therapies in breast cancer patients who progress after standard chemotherapy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02790580 (first posted June 6, 2016).

Phase Ib/II Dose Expansion Study of Lenvatinib Combined with Letrozole in Postmenopausal Women with Hormone Receptor-Positive Breast Cancer.

PURPOSE: RET is an estrogen response gene with preclinical studies demonstrating cross-talk between the RET and estrogen receptor (ER) pathways. We investigate the role of lenvatinib, a multikinase inhibitor with potent activity against RET, in patients with metastatic breast cancer. PATIENTS AND METHODS: Patients with advanced ER+/HER2- breast cancer were treated with lenvatinib plus letrozole in a phase Ib/II trial. Primary objectives included safety and recommended phase II dose (RP2D) determination in phase Ib, and objective response rates (ORR) in phase II dose expansion. RESULTS: Sixteen patients were recruited in dose finding, where deescalating doses of lenvatinib from 20 to 14 mg were investigated. Lenvatinib 14 mg plus letrozole 2.5 mg daily was determined as RP2D. Thirty-one patients with 5 median lines of prior therapy in the metastatic setting (range, 0-11) were recruited in dose expansion. In this cohort, ORR was 23.3% [95% confidence interval (CI) 9.9%-42.3%], with median duration of response (DoR) of 6.9 months [interquartile range (IQR) 5.9 to 13.1]. Clinical benefit rate ≥6 months (CBR) was 50.0% (95% CI, 31.3%-68.7%). Similar efficacy was observed in the subgroup of 25 patients who progressed on prior CDK4/6 inhibitor therapy [ORR 20.0% (95% CI, 6.8%-40.7%), median DoR 6.9 months (IQR 5.9-13.1), and CBR 52.0% (95% CI, 31.3%-72.2%)]. Pharmacodynamic studies showed target modulation, with paired tumor biopsies indicating downregulation of RET/pERK and improved vascular normalization index. CONCLUSIONS: Lenvatinib plus letrozole had manageable toxicity, with target engagement and preliminary antitumor activity observed, supporting further assessment in randomized studies.

Making sense of adjuvant chemotherapy in colorectal cancer.

Surgical resection is the only curative treatment for locoregional colon cancer. The goal of adjuvant chemotherapy is to eradicate micro-metastatic disease and improve survival. This has been most clearly demonstrated in stage III (node-positive) disease, whereas benefit of adjuvant chemotherapy in stage II disease remains controversial. In stage III colon cancer, 6 months of adjuvant chemotherapy with oxaliplatin-based chemotherapy have been accepted as the standard for the last 15 years. The recent IDEA collaboration has challenged this in 2018; while overall was a negative non-inferiority study, pre-planned subset analyses do support that for patients with low-risk stage III disease, 3 months of XELOX (capecitabine and oxaliplatin combination) is non-inferior to 6 months. In stage II colon cancer, where the potential benefit of adjuvant chemotherapy is small, the emergence of biomarkers has helped in decision-making. Tumors with deficient mismatch repair protein (dMMR) do not benefit from 5-fluorouracil-based chemotherapy. For patients with high clinicopathological risk stage II disease with proficient mismatch repair proteins and good performance status, six months of adjuvant chemotherapy is still recommended. In the management of rectal cancers, where the risk of local recurrence is higher, chemoradiation (CRT) is often included as neoadjuvant or adjuvant therapy in the management of stage II and III rectal cancer. The benefit of adjuvant chemotherapy in rectal cancer has been extrapolated from adjuvant colon cancer studies with updated results from adjuvant rectal cancer studies demonstrating similar benefits. This review summarizes the current landscape of adjuvant therapy for patients with resected stage II and III colorectal cancer.

Clinical genetic testing outcome with multi-gene panel in Asian patients with multiple primary cancers.

BACKGROUND: Developing multiple cancers is an indicator of underlying hereditary cancer predisposition, but there is a paucity of data regarding the clinical genetic testing outcomes of these patients. METHODS: We compared cancer index patients with ≥2 primary malignancies versus 1 primary cancer who underwent clinical evaluation and testing with multi-gene panels comprising up to 49 genes from 1998-2016. RESULTS: Among 1191 cancer index patients, 80.6%, 17.2%, and 2.2% respectively had 1, 2, and ≥3 primary malignancies. For patients with 2 primary cancers (n=205), the most common cancer pairs were bilateral breast (37.5%), breast-ovary (11.7%), endometrium-ovary (9.2%), colon-endometrium (3.9%) and colon-colon (3.4%). 42.3% patients underwent gene testing including 110/231 (47.6%) with multiple malignancies. Pathogenic variants were found more frequently in younger patients, in those with a family history of cancer related to the suspected syndrome, and a trend towards significance in those with multiple primary cancers (35.5% vs. 25.6%, p = 0.09). In patients with multiple cancers, pathogenic variants were most commonly identified in BRCA1 (38.5%), BRCA2 (17.9%), and the mismatch repair genes (20.5%), while 23.1% of pathogenic mutations were in other moderate- to high-penetrance cancer predisposition genes including APC, ATM, MUTYH, PALB2, RAD50 and TP53. CONCLUSION: Patients with multiple cancers were more likely to carry pathogenic mutations than those with single cancer. About three-quarters of deleterious mutations in patients with multiple primary cancers were in BRCA1/2 and the mismatch repair genes, but multi-gene panel testing facilitated the detection of mutations in another 6 genes and is warranted in this high-risk population.