Citations

Tumor cell proliferation rate determined by either Ki-67 index or mitotic count (MC) has shown to be a prognostic factor for gastrointestinal neuroendocrine tumors in general, and after its incorporation in the 2010 World Health Organization tumor grading system, it has become essentially mandatory in pathology reports for all gastrointestinal neuroendocrine tumors, regardless of tumor location. Nevertheless, clinical significance for the Ki-67 index or MC has not been well demonstrated in small intestinal neuroendocrine tumor (SINET), especially those without distant metastasis, the majority of which have very low proliferation rates. We assessed the clinical behavior of 130 SINETs in relation to stage, Ki-67 index, MC, and other pathologic features. Most SINETs (86%) were grade 1 and 14% were grade 2. There were no grade 3 tumors or poorly differentiated neuroendocrine carcinomas. On multivariate analysis, age, Ki-67 index >5%, MC >10/50 high-power field, stage IV, and liver metastases were associated with increased risk of death in all patients. When both stage and grade were considered, Ki-67 index >5% was associated with a nearly 4-fold increased risk of death in stage IV cases (n=60). In contrast, Ki-67 index did not show prognostic value for patients with stages I to III disease (n=70), although MC >1/50 high-power field was significantly associated with death on multivariable analysis. Our study confirms that liver metastasis and increased tumor cell proliferation rate are independent prognostic factors for SINETs, but shows that most SINETs have a very low proliferation rate, which limits its value for predicting tumor behavior. By combining staging and grading information, we demonstrate different roles and cutoff values of Ki-67 index and MC in SINET with different stages.

Abstract Purpose: Cyclin-dependent kinase (CDK) 4/6 drives cell proliferation in estrogen receptor–positive (ER+) breast cancer. This single-arm phase II neoadjuvant trial (NeoPalAna) assessed the antiproliferative activity of the CDK4/6 inhibitor palbociclib in primary breast cancer as a prelude to adjuvant studies. Experimental Design: Eligible patients with clinical stage II/III ER+/HER2− breast cancer received anastrozole 1 mg daily for 4 weeks (cycle 0; with goserelin if premenopausal), followed by adding palbociclib (125 mg daily on days 1–21) on cycle 1 day 1 (C1D1) for four 28-day cycles unless C1D15 Ki67 > 10%, in which case patients went off study due to inadequate response. Anastrozole was continued until surgery, which occurred 3 to 5 weeks after palbociclib exposure. Later patients received additional 10 to 12 days of palbociclib (Cycle 5) immediately before surgery. Serial biopsies at baseline, C1D1, C1D15, and surgery were analyzed for Ki67, gene expression, and mutation profiles. The primary endpoint was complete cell cycle arrest (CCCA: central Ki67 ≤ 2.7%). Results: Fifty patients enrolled. The CCCA rate was significantly higher after adding palbociclib to anastrozole (C1D15 87% vs. C1D1 26%, P < 0.001). Palbociclib enhanced cell-cycle control over anastrozole monotherapy regardless of luminal subtype (A vs. B) and PIK3CA status with activity observed across a broad range of clinicopathologic and mutation profiles. Ki67 recovery at surgery following palbociclib washout was suppressed by cycle 5 palbociclib. Resistance was associated with nonluminal subtypes and persistent E2F-target gene expression. Conclusions: Palbociclib is an active antiproliferative agent for early-stage breast cancer resistant to anastrozole; however, prolonged administration may be necessary to maintain its effect. Clin Cancer Res; 23(15); 4055–65. ©2017 AACR.

Purpose Everolimus improved median progression-free survival by 6.4 months in patients with advanced pancreatic neuroendocrine tumors (NET) compared with placebo in the RADIANT-3 study. Here, we present the final overall survival (OS) data and data on the impact of biomarkers on OS from the RADIANT-3 study. Methods Patients with advanced, progressive, low- or intermediate-grade pancreatic NET were randomly assigned to everolimus 10 mg/day (n = 207) or placebo (n = 203). Crossover from placebo to open-label everolimus was allowed on disease progression. Ongoing patients were unblinded after final progression-free survival analysis and could transition to open-label everolimus at the investigator’s discretion (extension phase). OS analysis was performed using a stratified log-rank test in the intent-to-treat population. The baseline levels of chromogranin A, neuron-specific enolase, and multiple soluble angiogenic biomarkers were determined and their impact on OS was explored. Results Of 410 patients who were enrolled between July 2007 and March 2014, 225 received open-label everolimus, including 172 patients (85%) randomly assigned initially to the placebo arm. Median OS was 44.0 months (95% CI, 35.6 to 51.8 months) for those randomly assigned to everolimus and 37.7 months (95% CI, 29.1 to 45.8 months) for those randomly assigned to placebo (hazard ratio, 0.94; 95% CI, 0.73 to 1.20; P = .30). Elevated baseline chromogranin A, neuron-specific enolase, placental growth factor, and soluble vascular endothelial growth factor receptor 1 levels were poor prognostic factors for OS. The most common adverse events included stomatitis, rash, and diarrhea. Conclusion Everolimus was associated with a median OS of 44 months in patients with advanced, progressive pancreatic NET, the longest OS reported in a phase III study for this population. Everolimus was associated with a survival benefit of 6.3 months, although this finding was not statistically significant. Crossover of patients likely confounded the OS results.