Molecular targeted therapies in advanced gastric cancer: does tumor histology matter?

It is increasingly recognized that gastric cancer is a heterogeneous disease which may be divided into subgroups based on histological, anatomical, epidemiological and molecular classifications. Distinct molecular drivers and tumor biology, and thus different treatment targets and predictive biomarkers, may be implicated in each subtype. However, there is little evidence in the literature regarding the correlation among these different classifications, and particularly the molecular aberrations present in each subtype. In this review, we approach advanced gastric cancer (AGC) by presenting aberrant molecular pathways and their potential therapeutic targets in gastric cancer according to histological and anatomical classification, dividing gastric cancer into proximal nondiffuse, distal nondiffuse and diffuse disease. Several pathways are involved predominantly, although not exclusively, in different subtypes. This may help to explain the disappointing results of many published AGC trials in which study populations were heterogeneous regardless of clinicopathological characteristics of the primary tumor. Histological and anatomical classification may provide insights into tumor biology and facilitate selection of an enriched patient population for targeted agents in future studies and in the clinic. However, some molecular pathways implicated in gastric cancer have not been studied in correlation with histological or anatomical subtypes. Further studies are necessary to confirm the suggestion that such classification may predict tumor biology and facilitate selection of an enriched patient population for targeted agents in future studies and in the clinic.

Abstract P4-13-04: Estrogen and Avoidance of Invasive Breast Cancer, Coronary Heart Disease and All-cause Mortality. Public Health Impact of Estrogen Guidelines for Women entering Menopause

BACKGROUND. Estrogen [E] for women entering menopause is not perceived beneficial for either iBrCa or CHD. However, data from RCTs suggest that use of Estrogen reduces: a. rates of invasive breast cancer [iBrCa], andb. atherogenesis, vessel pathology and in certain age groups, coronary heart disease [CHD].

OBJECTIVES: To estimate the population-level impact of Estrogen as part of hormone replacement therapy [HRT] for women entering menopause on rates of iBrCa, CHD and all cause mortality [AC- Mort] that could result from a change of Practice where Estrogen would be recommended for women entering menopause.

METHODOLOGY. Annualized rates of iBrCa, CHD and AC-Mort in women age 50–59, and annualized iBrCa rates for all participants and those without Past History of Benign Breast Disease [PHBBD] extracted from the results of the Women's Health Initiative trial [E] alone vs placebo [Refs 1,2], were applied to estimate the reduction in the Number of Avoided Events per 100,000 female population per annum [NAE].

The [NAE] over 10 years follow up was calculated as: NAE = (P − E) × 100,000 × 10 where P was the annualized rate among placebo participants and E was the annualized rate among Estrogen participants.

RESULTS. [Table 1]. Taking 100,000 exposed versus unexposed women age 50–59, and rate reduction due to [E] of −41% [HR=0.59], −20% [HR=0.80] and −27% [HR=0.73] for CHD, iBrCa and AC-Mort [Ref 1,2], respectively, there will be annual avoidance of −130 cases of CHD, −60 of iBrCa, and −130 of deaths from any cause. iBrCa annual avoidance for women any age, and those without PHBBD, were −80 and −150 events, respectively.

Is there a role for unstimulated thyroglobulin velocity in predicting recurrence in papillary thyroid carcinoma patients with detectable thyroglobulin after radioiodine ablation?

Background

In the follow-up of papillary thyroid cancer (PTC) patients treated with curative thyroidectomy and radioiodine ablation, raised thyroglobulin (Tg) predicts recurrence with reasonable sensitivity and specificity. However, a proportion of patients present with raised Tg level but no other clinical evidence of disease. Only limited data on Tg kinetics have been reported to date. Here we aim to evaluate the prognostic and predictive significance of nonstimulated serum Tg velocity (TgV).

Methods

Consecutive PTC patients treated with curative thyroidectomy and radioiodine ablation between 2003 and 2010 were analyzed. Patients with at least one detectable Tg measurement (>0.2 ng/mL) were included. TgV was defined as the annualized rate of Tg change. Logistic regression analyses were performed to evaluate the role of TgV in the prediction of disease recurrence. The optimal TgV cutoff was assigned by receiver–operating characteristic curve analysis. Overall survival of patients above versus below the TgV cutoff were determined by the Kaplan–Meier method and compared.

Results

Of a total of 501 patients, 87 had at least one Tg value >0.2 ng/mL; in these latter patients, 29 (33.3 %) developed recurrence. TgV was an independent predictor of the recurrence. TgV ≥0.3 ng/mL per year predicted recurrence with a sensitivity of 83.3 % and specificity of 94.4 %. Patients with TgV below the cutoff had a significantly better overall survival (p = 0.038).

Conclusions

TgV predicts recurrence with high sensitivity and specificity, and is a prognosticator of survival in postthyroidectomy and postablation PTC patients with raised Tg.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-012-2391-6) contains supplementary material, which is available to authorized users.

The use of single-agent sorafenib in the treatment of advanced hepatocellular carcinoma patients with underlying Child-Pugh B liver cirrhosis: a retrospective analysis of efficacy, safety, and survival benefits

BACKGROUND

This study explored the efficacy, tolerability, and survival benefits of using sorafenib in patients with Child-Pugh class B (CPB) cirrhosis.

METHODS

Patients with advanced hepatocellular carcinoma who were treated with sorafenib at Queen Mary Hospital, Hong Kong, China, were analyzed retrospectively. Treatment outcomes were analyzed according to their respective Child-Pugh status. Patients with CPB disease were further divided into CPB7 (those with a score of 7) and CPB8-9 (a score of 8 or 9) subgroups.

RESULTS

The baseline demographic parameters were comparable between 108 patients with Child-Pugh class A (CPA) disease and 64 CPB patients. Both clinical benefit rate (21.3% vs 32.4% vs 14.8%; P = .23) and progression-free survival (median: 3.2 months vs 3.2 months vs 2.3 months; P = .26) were similar among CPA, CPB7, and CPB8-9 groups, respectively. The overall survival was different among these groups (P = .002) and showed a trend toward worse outcome in CPB patients: the median was 6.1, 5.4, and 2.7 months among CPA, CPB7, and CPB8-9 patients, respectively. The commonest grade 3/4 adverse events were hand-foot syndrome (13.5%), diarrhea (9.9%), and rash (7.0%). Grade 3/4 leukopenia, thrombocytopenia, and anemia occurred in 2.9%, 5.3%, and 8.8% of the patients, respectively. Overall, the 3 groups of patients experienced similar incidence of most of these adverse events. Nonetheless, CPB patients experienced more anemia (P = .01), gastrointestinal bleeding (P = .02), and hepatic encephalopathy (P = .02).

CONCLUSIONS

CPA and CPB patients tolerated sorafenib similarly and derived similar clinical and progression-free survival benefit. Among CPB patients, most benefits were observed in patients with a score of 7. Nevertheless, CPB patients were more susceptible to developing cirrhotic complications, and thus more vigilant surveillance is needed.

Phase II study of bevacizumab and erlotinib in the treatment of advanced hepatocellular carcinoma patients with sorafenib-refractory disease

Background The combination of bevacizumab (B) and erlotinib (E) has shown promising clinical outcomes as the first-line treatment of advanced HCC patients. We aimed to evaluate the efficacy and safety of using combination of B + E in treating advanced HCC patients who had failed prior sorafenib treatment. Methods Eligible advanced HCC patients with documented radiological evidence of disease progression with sorafenib treatment were recruited. All patients received bevacizumab(B) at 10 mg/kg every 2 weeks with erlotinib(E) at 150 mg daily for a maximum of 6 cycles. Response assessments using both RECIST and modified RECIST criteria were performed after every 6 weeks. The primary endpoint was clinical benefit (CB) rate and a Simon two-stage design was employed. Results The trial was halted in the first stage according to the pre-set statistical criteria with 10 patients recruited. The median age was 47 years (range, 28–61) and all patients were in ECOG performance status 1. Eighty percent of patients were chronic hepatitis B carriers and all patients had Child A cirrhosis. Among these 10 patients, none of the enrolled patients achieved response or stable disease. The median time-to-progression was 1.81 months (95 % confidence interval [C.I.], 1.08–1.74 months) and overall survival was 4.37 months (95 % C.I., 1.08–11.66 months). Rash (70 %), diarrhea (50 %) and malaise (40 %) were the most commonly encountered toxicities. Conclusion The combination of B + E was well tolerated but had no activity in an unselected sorafenib-refractory advanced HCC population. Condensed abstract The combination of bevacizumab and erlotinib had no clinical activity in sorafenib-refractory HCC population.

Altered mTOR signaling and enhanced CYFIP2 expression levels in subjects with fragile X syndrome

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and autism. The protein (FMRP) encoded by the fragile X mental retardation gene (FMR1), is an RNA-binding protein linked to translational control. Recently, in the Fmr1 knockout mouse model of FXS, dysregulated translation initiation signaling was observed. To investigate whether an altered signaling was also a feature of subjects with FXS compared to typical developing controls, we isolated total RNA and translational control proteins from lymphocytes of subjects from both groups (38 FXS and 14 TD). Although we did not observe any difference in the expression level of messenger RNAs (mRNAs) for translational initiation control proteins isolated from participant with FXS, we found increased phosphorylation of the mammalian target of rapamycin (mTOR) substrate, p70 ribosomal subunit 6 kinase1 (S6K1) and of the mTOR regulator, the serine/threonine protein kinase (Akt), in their protein lysates. In addition, we observed increased phosphorylation of the cap binding protein eukaryotic initiation factor 4E (eIF4E) suggesting that protein synthesis is upregulated in FXS. Similar to the findings in lymphocytes, we observed increased phosphorylation of S6K1 in brain tissue from patients with FXS (n = 4) compared to normal age-matched controls (n = 4). Finally, we detected increased expression of the cytoplasmic FMR1-interacting protein 2 (CYFIP2), a known FMRP interactor. This data verify and extend previous findings using lymphocytes for studies of neuropsychiatric disorders and provide evidence that misregulation of mTOR signaling observed in the FXS mouse model also occurs in human FXS and may provide useful biomarkers for designing targeted treatments in FXS.

Targeted therapy in the management of advanced gastric cancer: are we making progress in the era of personalized medicine?

BACKGROUND

Gastric cancer is one of the leading causes of cancer death. With greater understanding of the molecular basis of carcinogenesis, targeted agents have led to a modest improvement in the outcome of advanced gastric cancer (AGC) patients.

METHODS AND RESULTS

We conducted an overview of the published evidence regarding the use of targeted therapy in AGC patients. Thus far, the human epidermal growth factor receptor (HER) pathway, angiogenic pathway, and phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin pathway have emerged as potential avenues for targeted therapy in AGC patients. The promising efficacy results of the Trastuzumab for Gastric Cancer trial led to the approved use of trastuzumab-based therapy as first-line treatment for patients with HER-2+ AGC. On the other hand, the Avastin® in Gastric Cancer trial evaluating bevacizumab in combination with chemotherapy did not meet its primary endpoint of a longer overall survival duration despite a significantly higher response rate and longer progression-free survival time in patients in the bevacizumab arm. Phase III data are awaited for other targeted agents, including cetuximab, panitumumab, lapatinib, and everolimus.

CONCLUSION

Recent progress in targeted therapy development for AGC has been modest. Further improvement in the outcome of AGC patients will depend on the identification of biomarkers in different patient populations to facilitate the understanding of gastric carcinogenesis, combining different targeted agents with chemotherapy, and unraveling new molecular targets for therapeutic intervention.

Colon cancer in a patient with underlying aplastic anemia: A clinical challenge

The association of gastrointestinal malignancy with aplastic anemia has rarely been reported in the literature. Although it is not clear whether there is any direct relationship between aplastic anemia and gastrointestinal cancers, a retrospective analysis did suggest the notion that patients with aplastic anemia might have a higher incidence of colorectal cancer. Here, we report the diagnostic and therapeutic challenges in managing a patient with aplastic anemia and advanced colorectal cancer. Early diagnosis is challenging due to overlapping symptomatology and clinical features, increased risk of diagnostic procedures, and confounding complications arising from aplastic anemia and its treatment. A high index of suspicion and multidisciplinary input are essential.

Understanding interprofessional communication: a content analysis of email communications between doctors and nurses

BACKGROUND

Clinical communication is recognized as a major source of errors in hospitals. The lack of documentation of communication, especially among verbal interactions, often creates hindrances and impedes improvement efforts. By providing smartphones to residents and encouraging nurses to communicate with residents by email shifted much of the communication to emails which permitted analysis of content.

OBJECTIVE

Description on the interprofessional email communication between doctors and nurses occurring on the general internal medicine wards at two academic hospitals.

DESIGN

A prospective analysis of email communications between doctors and nurses.

SETTING

34 out of the 67 residents who were on the general medicine clinical teaching units consented to allow analysis of their emails over a 6 month period.

MAIN MEASURES

Statistical tabulations were performed on the volume and frequency of communications as well the response time of messages. Two physicians coded the content of randomly selected emails for urgency, emotion, language, type of interaction, and subject content.

KEY RESULTS

A total of 13,717 emails were available for analysis. Among the emails from nurses, 39.1% were requests for a call back, 18.9% were requests for a response by email and the remaining 42.0% indicated no response was required from physicians. For the messages requesting a response by email, only 50% received an email response. Email responses had a median response time of 2.3 minutes. Content analysis revealed that messages were predominantly non-urgent. The two most frequent purposes for communications were to convey information (91%) and to request action by the physician (36%).

CONCLUSIONS

A smartphone-based email system facilitated the description and content analysis of a large amount of email communication between physicians and nurses. Our findings provide a picture of the communication between physicians, nurses and other healthcare professionals. This work may help inform the further development of information and communications technology that can improve clinical communication.

P5-21-01: A Renewable Tissue Resource of Phenotypically Stable Human Breast Cancer Xenografts for Preclinical Studies

Introduction Translational breast cancer research is hampered severely by difficulties in obtaining and studying primary human breast tissue, and by the lack of in vivo preclinical models that accurately reflect patient tumor biology. These limitations are due, in part, to the fact that traditional immunocompromised mouse models are not generally permissive for growth. We sought to circumvent some of these limitations by transplanting and growing human mammary tumors in the mammary fat pad of SCID/Beige immunocompromised mice in the absence of exogenous human fibroblasts.

Aims and Methods To establish a set of stable human breast cancer xenografts for preclinical studies. Human breast cancer biopsies were received, minced into small fragments and then transplanted directly into “cleared” fat pads of recipient SCID/Beige immunocompromised mice. Transplanted fat pads were checked weekly. After initial tumor was palpated and harvested, tumor fragments were transplanted into new SCID/Beige hosts for subsequent transplant generations. Serial immunohistochemical evaluations were performed to confirm human origin and biomarker status. Analytical flow cytometry for evaluating expression of proposed “cancer stem cell” markers, and gene and protein expression analysis were carried out on all stable lines.

Results and Conclusions Xenograft lines were established directly from breast cancer patient samples, without intervening culture in vitro, using the epithelium-free mammary fat pad as the transplantation site. Of the conditions tested, xenograft take rate was highest in the presence of a low-dose estradiol pellet without exogenous human fibroblasts. Thirty six stably transplantable xenograft lines representing 27 patients were established, using pre-treatment, mid-treatment, and/or post-treatment samples. Most patients yielding xenografts were “triple-negative” (ER-PR-HER2−) (n=21), we were able to establish lines from three ER-PR-HER2+ patients, one ER+PR+HER2−, one ER+PR-HER2−and one “triple-positive” (ER+PR+HER2+) patients. Serially passaged xenografts show phenotypic consistency with the tumor of origin at the histopathology level, and remarkable stability across multiple transplant generations at both the genomic, transcriptomic, and proteomic levels. Of 27 lines evaluated fully, thirteen xenografts showed metastasis to the mouse lung. These models thus serve as a renewable, quality-controlled tissue resource, and should prove useful for preclinical evaluation of experimental therapeutics.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-21-01.

P1-03-02: The Norton-Simon Hypothesis and Cancer Stem Cells: How Cancer Stem Cells May Explain the Effectiveness of Dose-Dense Chemotherapy

Background: Systemic therapies are effective initially in controlling and reversing tumor growth; however, residual cancers will invariably re-grow despite this initial response. We have published data from paired human breast cancer samples that standard therapy every three weeks kills dividing daughter cells but not tumor-initiating cells (TICs), so that samples obtained after therapy are enriched for CD44+/CD24−/low putative “tumor-initiating” or “cancer stem” cells, indicating that standard treatment regimens are missing the critical targets, TICs. Interestingly, we have recent data in human breast tumors that indicate that TICs may in fact be chemosensitive initially, with a decrease in TICs observed within two days of chemotherapy, but shortly thereafter, TICS are actually induced by chemotherapy.

Materials and Methods: To evaluate TICs response to chemotherapy, mice with human breast tumor xenograft lines BCM-2665a and BCM-2147 were treated with vehicle, 10-, or 33-mg/kg docetaxel, and then tumors were collected for TIC assays and molecular analysis at both 48 and 72h after treatment. Using Affymetrix gene expression microarrays and reverse phase protein array (RPPA) analysis with 119 different validated antibodies, we identified pathways involved in regulation of TICs. Results: According to flow cytometric analysis for TIC markers and mammosphere (MS) formation efficiency, BCM-2665 TICs were reduced by docetaxel treatment compared to vehicle-treated at 48h post 10 mg/kg docetaxel (4-fold decrease) and 48 and 72h post 33 mg/kg docetaxel compared to control (14- and 2-fold decrease, respectively). Although the BCM-2147 TICs did not significantly decrease at any time points or doses tested, they were clearly induced at 72h post-treatment compared to control. Additionally, BCM-2665 TICs were increased within 72h post 10 mg/kg docetaxel, indicating that these time points are ideal for defining the mechanisms responsible for induction of TICs. Ingenuity Pathway Analysis of Affymetrix microarray data for both BCM-2665 and BCM-2147 revealed induction of inflammatory pathways, suggesting leukocyte infiltration associated with induction of TICs. Furthermore, RPPA analysis confirmed gene expression changes from the microarray data, and implicated apoptosis and inflammatory pathways. Sixteen of 28 proteins significantly changed with activation of CSC are involved in development of leukocytes. Discussion: These findings are consistent with the Norton-Simon Hypothesis in that chemotherapy regimens given more frequently may in fact eliminate TICs, thereby explaining the proven increased effectiveness of dose-dense chemotherapy. Based on when TICs became chemoresistant, we are comparing dose-dense treatment (4 mg/kg docetaxel every 3 days) to a traditional single dose of 32 mg/kg, in an effort to eliminate the tumor cells that cause tumor recurrence. Furthermore, our analysis of gene expression at both the RNA and protein level implicated the immune cells as TICs inducers. Since our immunocompromised mice lack T- and B- cells but have active macrophages, macrophages are indicated as inducers of TICs. We are focusing our current efforts at identifying how immune cells activate TICs and thus enhance tumorigenesis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-03-02.

The outcomes and safety of single-agent sorafenib in the treatment of elderly patients with advanced hepatocellular carcinoma (HCC)

BACKGROUND

With the aging population, hepatocellular carcinoma (HCC) in the elderly represents a significant health burden. We aimed to evaluate and compare the efficacy and tolerability of single-agent sorafenib in treating elderly patients with advanced HCC versus the younger population.

METHODS

We retrospectively analyzed a consecutive cohort of advanced HCC patients with Child-Pugh A or B liver function and an Eastern Cooperative Oncology Group performance status score of 0-2 treated with sorafenib. The patients were categorized into older (age ≥70 years) and younger (age <70 years) groups. Treatment outcomes and related adverse events (AEs) were compared.

RESULTS

In total, 172 patients, 35 in the older (median age, 73 years) and 137 in the younger (median age, 55 years) group, were analyzed. The median progression-free survival time was similar in the older and younger groups (2.99 months versus 3.09 months; p = .275), as was the overall survival time (5.32 months versus 5.16 months; p = .310). Grade 3 or 4 AEs were observed in 68.6% of older and 62.7% of younger patients (p = .560), with neutropenia (11.4% versus 0.7%; p = .007), malaise (11.4% versus 2.2%; p = .033), and mucositis (5.7% versus 0.0%; p = .041) being more frequently reported in the elderly cohort.

CONCLUSIONS

The survival benefits and overall treatment-related AEs of sorafenib are comparable in elderly and younger advanced HCC patients. Nevertheless, more vigilant monitoring in the elderly is warranted because they are more susceptible to develop neutropenia, malaise, and mucositis.

The association of magnetic resonance imaging (MRI)-detected structural pathology of the knee with crepitus in a population-based cohort with knee pain: the MoDEKO study

Osteoarthritis (OA) is the most common arthropathy of the knee joint(1). Symptoms reported by patients and signs noted during physical examination guide clinicians in identifying subjects with knee OA(2-4). Pain is one of the most important symptoms reported by subjects with knee OA(2,3). Although very common, pain is a non-specific symptom, related to pathology in several structures within the knee joint, and includes synovitis(5), subchondral bone marrow lesions(6), and joint effusion(7). Further, pain is a subjective symptom that cannot be directly measured or assessed during physical examination. Crepitus or crepitation in association with arthritis is defined as a crackling or grinding sound on joint movement with a sensation in the joint. Crepitus may occur with or without pain and is a common finding during physical examination in subjects with knee OA(2-4,8,9). It is not known whether crepitus is related to pathology in various structures within the knee. The aim of our study was to determine the cross-sectional associations of structural pathologies within the knee with crepitus in a population-based cohort with knee pain, using magnetic resonance imaging (MRI). Subjects with knee pain were recruited as a random population sample, with crepitus assessed in each compartment of the knee using a validated and standardized approach during physical examination(10). MRI of the knee was performed to assess cartilage morphology, meniscal morphology, osteophytes, cruciate ligaments, and collateral ligaments. For both compartment-specific and whole-knee analyses, a multiple logistic regression analysis was performed to assess the associations of MRI-detected structural pathology with crepitus, adjusting for potential confounders. Variables were selected by backwards elimination within each compartment and in the overall knee models, and only statistically significant variables remained in the "selected" models; remaining variables in these models are adjusted for each other. An increased risk for compartment-specific crepitus was associated with osteophytes at the patellofemoral (PF) and lateral tibiofemoral (LTF) joints. Crepitus was associated with osteophytes and medial collateral ligament (MCL) pathology at the medial tibiofemoral (MTF) compartment, but cartilage damage was negatively associated with crepitus at this compartment. In the selected whole-knee model, only meniscal tears were associated with an increased risk for general crepitus. Thus, it seems that crepitus may be associated with pathology in several internal structures.