Abstract P4-02-05: A novel 64Cu-liposomal PET agent (MM-DX-929) predicts response to liposomal chemotherapeutics in preclinical breast cancer models

Background: Liposomal anthracyclines (such as pegylated liposomal doxorubicin (PLD) or HER2-targeted liposomal doxorubicin (MM-302)) are being used and/or evaluated for the clinical management of breast cancer, but responses vary from patient to patient. It is hypothesized that variability in the deposition of liposomal therapeutics within tumors leads to differences in drug exposure, thereby directly influencing tumor response. We have developed MM-DX-929, a novel 64Cu-liposomal PET imaging agent, as a clinically-implementable tool to investigate whether image-based quantification of liposome deposition in tumors can predict treatment response to liposomal chemotherapeutics, including PLD, MM-302 and/or liposomal irinotecan (MM-398).

Objectives: Our primary objective is to demonstrate that the extent of tumor uptake of MM-DX-929 is predictive of tumor response to MM-302 in preclinical breast cancer xenograft models. A secondary objective is to enable clinical translation of MM-DX-929 to enable incorporation into existing therapeutic trials.

Methods: Mice bearing BT474-M3 mammary and subcutaneous tumors were injected intravenously with MM-DX-929 prior to dosing with MM-302. PET/CT imaging was performed at 16h post MM-DX-929 injection, and tumor uptake was determined. Response to treatment was quantified as tumor volume changes measured over a 2-month period by MRI.

Results: Tumor deposition of MM-DX-929 administration correlated well with treatment response to MM-302 (Spearman correlation coefficient of −0.891 and a p-value of 0.0004). MM-DX-929 accumulation in tumors prior to the start of the MM-302 treatment successfully predicted improved tumor growth inhibition following MM-302 treatment.

Conclusion: These findings support trials of MM-DX-929 as a predictive imaging agent to select patients who are most likely to respond to liposomal therapies. The clinical development of MM-DX-929 for identification of breast cancer patients likely to respond to liposomal therapeutics is currently being pursued.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-02-05.

MAPPED study design: a 6 month randomised controlled study to evaluate the effect of dutasteride on prostate cancer volume using magnetic resonance imaging

OBJECTIVE

To evaluate the percentage change in volume of prostate cancer, as assessed by T2-weighted MRI, following exposure to dutasteride (Avodart) 0.5mg daily for six months.

PATIENTS AND METHODS

MRI in Primary Prostate cancer after Exposure to Dutasteride (MAPPED) is a double-blind, placebo-controlled trial, supported by GlaxoSmithKline (GSK). Men with prostate cancer suitable for active surveillance (low-intermediate risk prostate cancer on biopsy), and a visible lesion on T2-weighted MRI of at least 0.2 cc, were eligible for consideration. Forty-two men were randomised to 6 months of daily dutasteride 0.5mg or placebo. Multi-parametric MRI (mpMRI) scans were performed at baseline, 3 and 6 months. The percentage changes in cancer volume over time will be compared between the dutasteride and placebo groups. Planned analyses will examine the association between tumour volume and characteristics (perfusion and contrast washout) as seen on mpMRI, HistoScan ultrasound and biopsy histopathology in both groups.

DISCUSSION

MAPPED is the first randomised controlled trial to use mpMRI to look at the effect of dutasteride on the volume of prostate cancer. If dutasteride is shown to reduce the volume of prostate cancer, it might be considered as an adjunct for men on active surveillance. Analysis of the placebo arm will allow us to comment on the short-term natural variability of the MR appearance in men who are not receiving any treatment.

CONCLUSION

MAPPED will evaluate the short-term effect of dutasteride on prostate cancer volume, as assessed by mpMRI, in men undergoing active surveillance for low or intermediate risk prostate cancer. The study completed recruitment in January 2012.

Oncolytic measles virus strains have significant antitumor activity against glioma stem cells

Glioblastoma (GBM) is the most common primary brain tumor in adults and has a dismal prognosis despite multimodality treatment. Given the resistance of glioma stem cells (GSC) to chemotherapy and radiation therapy, their eradication could prevent tumor recurrence. We sought to evaluate the antitumor activity of measles virus (MV) derivatives against GSC. We generated neurosphere cultures from patient-derived primary tumor GBM xenografts, and we characterized them for the GSC markers CD133, SOX2, Nestin, ATF5 and OLIG2. Using the MV-strains MV-GFP, MV-CEA and MV-NIS we demonstrated infection, viral replication and significant cytopathic effect in vitro against GSC lines. In tumorigenicity experiments, GBM44 GSC were infected with MV in vitro and subsequently implanted into the right caudate nucleus of nude mice: significant prolongation of survival in mice implanted with infected GSC was observed, compared with mock-infected controls (P=0.0483). In therapy experiments in GBM6 and GBM12 GSC xenograft models, there was significant prolongation of survival in MV-GFP-treated animals compared with inactivated virus-treated controls (GBM6 P=0.0021, GBM12 P=0.0416). Abundant syncytia and viral replication was demonstrated in tumors of MV-treated mice. Measles virus derivatives have significant antitumor activity against glioma-derived stem cells in vitro and in vivo.

Retrospective analysis of treatment tolerability in elderly oncological patients receiving cytotoxic therapy in a community setting

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Background: Cancer is highly prevalent in those above the age of 65 years. Elderly oncological patients are under-represented in clinical trials and there is a lack of clinical data to guide treatment decisions in this group of patients. We evaluated the cytotoxic treatment tolerability in this group of patients in a community hospital. Methods: Cytotoxic chemotherapies and tyrosine kinase inhibitors administered in Gold Coast Hospital to patients above 65 years of age between March 2010 and March 2011 were included. Data including number of comorbidities, concurrent medicines, ECOG status and treatment drug dose adjustment were obtained. The outcomes of treatment including treatment completion, early termination and its reason, toxicities and hospital admissions during treatment were also collected. Results: A total of 206 patients were identified. Majority had an ECOG score of 0 to 1 (89%) and number of co-morbidities between 0 and 3 (96%). Eighty percent of patients had initial or subsequent treatment dose reduction. Despite this, 53% of patients (n=109) did not complete the planned treatment; 68% had disease progression but 31% was due to treatment intolerance. There was a high number of reported grade 3 and 4 toxicities (n=84) and hospitalisations during treatment (n=154). Conclusions: There is a high rate of dose reduction and noncompletion of cytotoxic treatments even in a relatively healthy elderly population. We propose further prospective study incorporating in-depth geriatric assessment to evaluate elderly patients suitability for cytotoxic treatments. [Table: see text]

Prostatic cancer surveillance following whole-gland high-intensity focused ultrasound: comparison of MRI and prostate-specific antigen for detection of residual or recurrent disease

OBJECTIVE

This retrospective study compares dynamic contrast-enhanced (DCE) MRI with the serial prostate-specific antigen (PSA) measurement for detection of residual disease following whole-gland high-intensity focused ultrasound (HIFU) therapy of prostate cancer.

METHODS

Patients in whom post-HIFU DCE-MRI was followed within 3 months by ultrasound-guided transrectal biopsy were selected from a local database. 26 patients met the study inclusion criteria. Serial PSA levels following HIFU and post-HIFU follow-up MRI were retrieved for each patient. Three radiologists unaware of other investigative results independently assessed post-HIFU MRI studies for the presence of cancer, scoring on a four-point scale (1, no disease; 2, probably no disease; 3, probably residual disease; and 4, residual disease). Sensitivity, specificity and receiver operating characteristic (ROC) analysis were performed for each reader, post-HIFU PSA nadir and pre-biopsy PSA level thresholds of >0.2 and >0.5 ng ml(-1).

RESULTS

The sensitivity of DCE-MRI for detection of residual disease for the three readers ranged between 73% and 87%, and the specificity between 73% and 82%. There was good agreement between readers (κ = 0.69-0.77). The sensitivity and specificity of PSA thresholds was 60-87% and 73-100%, respectively. The area under the ROC curve was greatest for pre-biopsy PSA (0.95).

CONCLUSION

DCE-MRI performed following whole-gland HIFU has similar sensitivity and specificity and ROC performance to serial PSA measurements for detection of residual or recurrent disease.

Comparative analysis of Shwachman-Diamond syndrome to other inherited bone marrow failure syndromes and genotype-phenotype correlation

Our knowledge of the phenotypes of inherited bone marrow failure syndromes (IBMFSs) derives from case reports or case series in which only one IBMFS was studied. However, the substantial phenotypic overlap necessitates comparative analysis between the IBMFSs. Shwachman-Diamond syndrome (SDS) is an IBMFS that the appreciation of what comprises its clinical phenotype is still evolving. In this analysis we used data on 125 patients from the Canadian Inherited Marrow Failure Study (CIMFS), which is a prospective multicenter population-based study. Thirty-four cases of SDS patients were analyzed and compared to other patients with the four most common IBMFSs on the CIMFS: Diamond Blackfan anemia, Fanconi anemia (FA), Kostmann/severe congenital neutropenia and dyskeratosis congenita (DC). The diagnosis of SDS, FA and DC was often delayed relative to symptoms onset; indicating a major need for improving tools to establish a rapid diagnosis. We identified multiple phenotypic differences between SDS and other IBMFSs, including several novel differences. SBDS biallelic mutations were less frequent than in previous reports (81%). Importantly, compared to patients with biallelic mutations, patients with wild type SBDS had more severe hematological disease but milder pancreatic disease. In conclusion, comprehensive study of the IBMFSs can provide useful comparative data between the disorders. SBDS-negative SDS patients may have more severe hematological failure and milder pancreatic disease.

Genetic analysis of inherited bone marrow failure syndromes from one prospective, comprehensive and population-based cohort and identification of novel mutations

INTRODUCTION

Inherited bone marrow failure syndromes (IBMFSs) often have substantial phenotypic overlap, thus genotyping is often critical for establishing a diagnosis.

OBJECTIVES AND METHODS

To determine the genetic characteristics and mutation profiles of IBMFSs, a comprehensive population-based study that prospectively enrols all typical and atypical cases without bias is required. The Canadian Inherited Marrow Failure Study is such a study, and was used to extract clinical and genetic information for patients enrolled up to May 2010.

RESULTS

Among the 259 primary patients with IBMFS enrolled in the study, the most prevalent categories were Diamond-Blackfan anaemia (44 patients), Fanconi anaemia (39) and Shwachman-Diamond syndrome (35). The estimated incidence of the primary IBMFSs was 64.5 per 10(6) births, with Fanconi anaemia having the highest incidence (11.4 cases per 10(6) births). A large number of patients (70) had haematological and non-haematological features that did not fulfil the diagnostic criteria of any specific IBMFS category. Disease-causing mutations were identified in 53.5% of the 142 patients tested, and in 16 different genes. Ten novel mutations in SBDS, RPL5, FANCA, FANCG, MPL and G6PT were identified. The most common mutations were nonsense (31 alleles) and splice site (28). Genetic heterogeneity of most IBMFSs was evident; however, the most commonly mutated gene was SBDS, followed by FANCA and RPS19.

CONCLUSION

From this the largest published comprehensive cohort of IBMFSs, it can be concluded that recent advances have led to successful genotyping of about half of the patients. Establishing a genetic diagnosis is still challenging and there is a critical need to develop novel diagnostic tools.

Selective salpingography and recanalisation of blocked fallopian tubes

Fallopian tubal disease is a common cause of subfertility. Reproductive surgery or assisted reproduction techniques such as in vitro fertilization (IVF) have been the main treatment options for patients with tubal disease in Ireland, although access to these treatments remains limited. We describe a case of pregnancy following selective salpingography and fallopian tube recanalisation.