Khaldoun Almhanna

A phase II study of RO4929097 in metastatic colorectal cancer

BACKGROUND The Notch signalling pathway is activated in a variety of malignancies and has been implicated in colorectal cancer progression. One of the first steps in the Notch pathway activation is mediated by γ-secretase, a proteolytic enzyme which produces an activated intracellular Notch (ICN). RO4929097 is a selective inhibitor of γ-secretase. We tested the activity of RO4929097 in patients with metastatic, refractory colorectal cancer. PATIENTS AND METHODS Patients with metastatic colorectal cancer who had received at least two prior lines of systemic chemotherapy were enrolled on the study. Patients were treated with RO4929097 at its recommended phase II dose of 20mg daily, 3 days on and 4 days off continuously. Cycle length was 28 days. Imaging was performed every two cycles. Archival tissue specimens were stained immunohistochemically for components of the notch pathway: Notch1, ICN and the downstream target HES1. RESULTS Thirty-seven patients were enrolled of whom 33 were evaluable for toxicity and response. Immunohistochemical analysis of archival tissues demonstrated positive staining for the notch receptor as well as intracellular notch and the downstream gene HES1 in the majority of patients. Nevertheless, no objective radiographic responses were observed in this group and only six patients had stable disease as their best response. Median PFS was 1.8 months and median overall survival (OS) was 6.0 months. CONCLUSION In this study of RO4929097 in patients with refractory metastatic colorectal cancer, no radiographic responses were seen and time to progression was short, which suggests that RO4929097 at the study dose and schedule has minimal single agent activity in this malignancy.

Radiation Therapy and Esophageal Cancer

BACKGROUND Squamous cell carcinoma and adenocarcinoma account for more than 90% of all esophageal cancer cases. Although the incidence of squamous cell carcinoma has declined, the incidence of adenocarcinoma has risen due to increases in obesity and gastroesophageal reflux disease. METHODS The authors examine the role of radiation therapy alone (external beam and brachytherapy) for the management of esophageal cancer or combined with other modalities. The impact on staging and appropriate stratification of patients referred for curative vs palliative intent with modalities is reviewed. The authors also explore the role of emerging radiation technologies. RESULTS Current data show that neoadjuvant chemoradiotherapy followed by surgical resection is the accepted standard of care, with 3-year overall survival rates ranging from 30% to 60%. The benefit of adjuvant radiation therapy is limited to patients with node-positive cancer. The survival benefit of surgical resection after chemoradiotherapy remains controversial. External beam radiation therapy alone results in few long-term survivors and is considered palliative at best. Radiation dose-escalation has failed to improve local control or survival. Brachytherapy can provide better long-term palliation of dysphagia than metal stent placement. Although three-dimensional conformal treatment planning is the accepted standard, the roles of IMRT and proton therapy are evolving and potentially reduce adverse events due to better sparing of normal tissue. CONCLUSIONS Future directions will evaluate the benefit of induction chemotherapy followed by chemoradiotherapy, the role of surgery in locally advanced disease, and the identification of responders prior to treatment based on microarray analysis.

Capecitabine vs continuous infusion 5-FU in neoadjuvant treatment of rectal cancer. A retrospective review

BackgroundStandard therapy for locally advanced rectal cancer (LARC) is concurrent neo-adjuvant chemo-radiation using infusional 5-fluorouracil (CIV-5-FU). Capecitabine (CAP) offers a convenient oral replacement for CIV-5-FU. There is no randomized trial comparing infusional 5-FU to capecitabine. We retrospectively compared the safety and efficacy of CAP-based regimens with well-established CIV-5-FU-based regimens in LARC.Materials and methodsWe collected published data on 542 patients treated on either CIV-5-FU (197) or CAP (345) with concurrent radiation (external radiation treatment, XRT) for LARC. This included Phase I or II studies published or available from Pubmed. Safety was assessed by determining proportion of patients who experienced grade III/IV adverse effects. Efficacy was assessed by determining pathological complete response (pCR). Chi-square tests were used to compare the two regimens. A P value less than 0.05 was considered statistically significant. Statistical tests were further corrected for multiplicity using the method of Benjamini and Yekutieli (Ann Stat, 29(4):1165–1188, 2001).ResultspCR was significantly higher in patients getting CAP vs CIV-5-FU (25 vs 13%; P = 0.008,.Padj = 0.034). Both regimens were generally well tolerated. There was no grade IV toxicity reported. Grade III hand foot syndrome was more common in the CAP group, and grade III diarrhea was more common in the CIV group.ConclusionsCAP when compared to CIV seems to have superior efficacy with reasonable toxicities. It is reasonable to treat LARC with CAP + XRT.

Comparative outcomes for three-dimensional conformal versus intensity-modulated radiation therapy for esophageal cancer

Emerging data suggests a benefit for using intensity modulated radiation therapy (IMRT) for the management of esophageal cancer. We retrospectively reviewed patients treated at our institution who received definitive or preoperative chemoradiation with either IMRT or 3D conformal radiation therapy (3DCRT) between October 2000 and January 2012. Kaplan Meier analysis and the Cox proportional hazard model were used to evaluate survival outcomes. We evaluated a total of 232 patients (138 IMRT, 94 3DCRT) who received a median dose of 50.4 Gy (range, 44-64.8) to gross disease. Median follow up for all patients, IMRT patients alone, and 3DCRT patients alone was 18.5 (range, 2.5-124.2), 16.5 (range, 3-59), and 25.9 months (range, 2.5-124.2), respectively. We observed no significant difference based on radiation technique (3DCRT vs. IMRT) with respect to median overall survival (OS) (median 29 vs. 32 months; P = 0.74) or median relapse free survival (median 20 vs. 25 months; P = 0.66). On multivariable analysis (MVA), surgical resection resulted in improved OS (HR 0.444; P < 0.0001). Superior OS was also associated on MVA with stage I/II disease (HR 0.523; P = 0.010) and tumor length ≤5 cm (HR 0.567; P = 0.006). IMRT was also associated on univariate analysis with a significant decrease in acute weight loss (mean 6% + 4.3% vs 9% + 7.4%, P = 0.012) and on MVA with a decrease in objective grade ≥3 toxicity, defined as any hospitalization, feeding tube, or >20% weight loss (OR 0.51; P = 0.050). Our data suggest that while IMRT-based chemoradiation for esophageal cancer does not impact survival there was significantly less toxicity. In the IMRT group there was significant decrease in weight loss and grade ≥3 toxicity compared to 3DCRT.

Stability of endoscopic ultrasound-guided fiducial marker placement for esophageal cancer target delineation and image-guided radiation therapy

PURPOSE Fiducial markers have been integrated into the management of multiple malignancies to guide more precise delivery of radiation therapy (RT). Fiducials placed at the margins of esophageal tumors are potentially useful to facilitate both RT target delineation and image-guided RT (IGRT). In this study, we report on the stability of endoscopic ultrasound (EUS)-guided fiducial placement for esophageal cancers and utilization for radiation treatment planning and IGRT. METHODS An institutional review board-approved database was queried for patients treated for esophageal cancer with chemoradiotherapy (CRT). Patients included in the analysis had a diagnosis of esophageal cancer, were referred for treatment with CRT, and had fiducials placed under EUS guidance. Images acquired at time of radiation treatment planning, daily IGRT imaging, post-treatment restaging, and surveillance scans were analyzed to determine the stability of implanted markers. RESULTS We identified 60 patients who underwent EUS-guided fiducial marker placement near the margins of their esophageal tumors in preparation for RT treatment planning. A total of 105 fiducial markers were placed. At time of CT simulation, 99 markers were visualized. Fifty-seven patients had post-treatment imaging available for review. Of the 100 implanted fiducials in these 57 patients, 94 (94%) were visible at time of RT simulation. Eighty-eight (88%) fiducials were still present post-treatment imaging at a median of 107 days (range, 33-471 days) after implantation. CONCLUSIONS EUS-guided fiducial marker placement for esophageal cancer aids in target delineation for radiation planning and daily IGRT. Fiducial stability is reproducible and facilitates conformal treatment with image-guided RT techniques.

Increased survival associated with surgery and radiation therapy in metastatic gastric cancer: a Surveillance, Epidemiology, and End Results database analysis.

Patients with metastatic gastric cancer have poor survival. The purpose of this study was to compare outcomes of metastatic gastric cancer patients stratified by surgery and radiation therapy.

Multimodality approach for locally advanced esophageal cancer.

Carcinoma of the esophagus is an aggressive and lethal malignancy with an increasing incidence worldwide. Incidence rates vary internationally, with the highest rates found in Southern and Eastern Africa and Eastern Asia, and the lowest in Western and Middle Africa and Central America. Patients with locally advanced disease face a poor prognosis, with 5-year survival rates ranging from 15%-34%. Recent clinical trials have evaluated different strategies for management of locoregional cancer; however, because of stage migration and changes in disease epidemiology, applying these trials to clinical practice has become a daunting task. We searched Medline and conference abstracts for randomized studies published in the last 3 decades. We restricted our search to articles published in English. Neoadjuvant chemoradiotherapy followed by surgical resection is an accepted standard of care in the United States. Esophagectomy remains an essential component of treatment and can lead to improved overall survival, especially when performed at high volume institutions. The role of adjuvant chemotherapy following curative resection is still unclear. External beam radiation therapy alone is considered palliative and is typically reserved for patients with a poor performance status.

Current status of novel agents in advanced gastroesophageal adenocarcinoma.

Gastroesophageal (GE) adenocarcinomas are highly lethal malignancies and despite multiple chemotherapy options, 5-year survival rates remain dismal. Chemotherapy is the mainstay of treatment but patients are often limited by toxicity and poor performance status. Because of molecular heterogeneity, it is essential to classify tumors based on the underlying oncogenic pathways and develop targeted therapies that act on individual tumors. Trastuzumab, a human epidermal growth factor receptor type 2 (HER2) monoclonal antibody, was the first such agent shown to improve response rate, progression free survival (PFS), and overall survival (OS) when added to cisplatin based chemotherapy in patients with HER2 over-expressing GE junction (GEJ) and gastric adenocarcinomas. However, HER2 over expressing GE tumors are in the minority and the need for additional targeted agents is urgent. Though many agents are in development, incorporating targeted therapy in the treatment of GE cancers comes with a unique set of challenges. In this review, we outline oncogenic pathways relevant to GE adenocarcinomas, including HER2, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), hepatocyte growth factor (HGF), and c-Met, and discuss recent trials with agents targeting these pathways.

Outcomes of Therasphere Radioembolization for Colorectal Metastases

INTRODUCTION The liver is the most common site for colorectal cancer (CRC) metastases. Radioembolization with yttrium-90 (Y90) represents an alternative approach in the management of unresectable hepatic colorectal metastases. The objective of this study was to evaluate outcomes after treatment with Y90. MATERIALS AND METHODS A retrospective review of patients undergoing Y90 glass microsphere treatment for metastatic CRC from 2009 to 2013 was conducted. Multivariable analysis (MVA) of factors related to overall survival (OS) was performed using the Cox proportional hazard and OS estimates were calculated using the Kaplan-Meier method. RESULTS We identified 68 patients. Median and 2-year OS were 11.6 months and 34%. For patients with ≤ 25% hepatic burden of disease (HBD) and 1 chemotherapy regimen, 2-year OS was 63%. Median and 2-year OS for patients with ≤ 25% versus > 25% HBD were 19.6 months and 42% versus 3.4 months and 0% (P < .0001). Univariate analysis revealed that higher HBD, ≥ 3 lines of chemotherapy received, and higher carcinoembryonic antigen (CEA) were found to be significant predictors of worse OS. MVA revealed age, > 25% HBD, ≥ 3 lines of chemotherapy, and higher CEA were independently prognostic for increased mortality, and resected status of the primary tumor was associated with decreased mortality. The presence of extrahepatic metastases was not prognostic. Toxicities were mild and only 5 patients experienced Grade 3/4 biochemical toxicity. CONCLUSION Yttrium-90 was associated with acceptable OS with minimal morbidity in this series. Minimal exposure to chemotherapy and low HBD were found to be associated with better OS, however, even patients with chemotherapy-refractory disease received a benefit from treatment.

Targeting the Human Epidermal Growth Factor Receptor 2 in Esophageal Cancer

The importance of human epidermal growth factor-2 (HER2) in terms of prognosis and aggressiveness of growth has long been known in breast cancer, and interruption of its growth cascade by agents such as trastuzumab and lapatinib has markedly improved outcomes for these patients with HER2 overexpression. HER2 overexpression also occurs in many other tumor types, including esophageal cancer. In this disease, a different scoring system for determining overexpression is used. Limited data exist concerning the biological and therapeutic implications of HER2 overexpression in esophageal cancer. One trial, the so-called ToGA trial, included patients with advanced gastric and gastroesophageal junction (GEJ) tumors that overexpressed HER2. Patients who received trastuzumab plus cisplatin-based chemotherapy had more responses and longer progression-free and overall survival than those who received the chemotherapy alone. Enthusiasm concerning these results must be tempered by the facts that only 25% of the study group had GEJ tumors and, of these, only 33% had HER2 overexpression. Thus, the role of trastuzumab in the management of HER2-overexpressing esophageal cancers remains to be determined. In addition to presenting data on the HER2 cascade, the authors review clinical trials performed to date and also present the validated standard scoring system for HER2 overexpression in esophageal cancer.