Abstract P6-08-08: Age-Related differences in clinicopathologic features and survival amongst women with triple negative breast cancer: A population-based study

INTRODUCTION: Women with triple-negative breast cancers (TNBC) have a tendency to present at younger ages and with more advanced disease. We sought to comprehensively evaluate the characteristic features, surgical management, and survival outcomes of a large, population-based cohort of patients with TNBC according to age at diagnosis.

METHODS: We queried the Surveillance, Epidemiology, and End Results (SEER) database to identify women aged 18 years or older with a diagnosis of TNBC between 2010-2014. Clinicopathologic and treatment level variables were compared amongst TNBC patients according to age at the time of TNBC diagnosis. The Kaplan-Meier method and Cox PH Regression was then used to examine short-term breast cancer-specific survival (BCSS) outcomes.

RESULTS: Between 2010-2014, 214,138 women were diagnosed with breast cancer, of which 23,614 (11.13%) had TNBC. The median age at TNBC diagnosis was 57.7 years. Younger TNBC patients were more likely to be of African American (<40 years, 20.1% vs. ≥70 years, 15.5%; p<0.001) or Hispanic race (<40 years, 21.9% vs. ≥70 years, 7.0%; p<0.001), diagnosed with larger tumors (T2-T3; <40 years, 70.2%; 40-49 years, 61.7%; 50-59 years, 55%; 60-69 years, 48.1%; ≥70 years, 49.5%; p<0.001) and present with lymph node positive disease (<40 years, 36.7%; 40-49 years, 34.8%; 50-59 years, 32.5%; 60-69 years, 27.5%; ≥70 years, 27.9%; p<0.001). With respect to local therapy, younger women also had a greater tendency to undergo bilateral mastectomy (<40 years, 34.3%; 40-49 years, 23.1%; 50-59 years, 13.4%; 60-69 years, 8.4%; ≥70 years, 3.3%; p<0.001). The estimated one and four-year BCSS for the entire cohort was 94.4% and 79.7%, respectively, with the youngest women <40 years and older women ≥70 years demonstrating the poorest unadjusted BCSS at four years (<40 years, 76.95%; 40-49 years, 82.1%; 50-59 years 80.9%; 60-69 years 81.7%; ≥70 years, 78.6%; log rank p<0.001). In Cox PH analysis adjusting for race, stage, pathologic features, and local therapy, age greater than 70 years remained significantly associated with worse cancer-specific survival (HR1.60, 95% CI 1.39-1.84).

CONCLUSION: In the population studied, more than 40% of very young women with TNBC are of African American or Hispanic race. When compared to older ages, younger women with TNBC are more likely to receive bilateral mastectomy and have more advanced stage at presentation. Women at both age extremes (≥70 years and <40 years at diagnosis) demonstrate worse cancer-specific survival outcomes. In older women, this may be due to undertreatment, and in younger women, to delays in diagnosis and/or worse tumor biology. Further studies are needed to evaluate age-related discrepancies in local and systemic therapy and cancer-specific survival in TNBC.

Citation Format: Wong SM, Boileau J-F, Martel K, Ferrario C, Basik M. Age-Related differences in clinicopathologic features and survival amongst women with triple negative breast cancer: A population-based study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-08.

Abstract P3-15-02: Treat ER+ight Canadian prospective observational study in HR+ advanced breast cancer: 2nd interim analysis

Treat ER+ight is the 1st prospective observational study in Canadian postmenopausal women with HR+ HER2– advanced breast cancer currently receiving endocrine therapy (ET) alone or in combination with targeted therapy (TT) (NCT02753686).

Methods: This pre-planned interim analysis describes baseline characteristics, treatment sequence, monitoring patterns, patient-reported quality-of-life (QoL) and resource utilization of patients enrolled in ET and ET+TT cohorts within the 1st 3 months of therapy. At data cut-off (13Mar'17), 100 patients were enrolled from 24 sites since Mar'16.

Results:

Baseline Patient and Disease Characteristics ET (n=42)ET + TT (n=58)Median age, years (range)70 (37-88)63 (39-80)ECOG 0-1, (%)6072Median time since primary BC diagnosis, years (range)4.5 (0-37)5 (0-25)Median time with advanced BC diagnosis, years (range)1 (0-16)1 (0-7)Sites of metastases (%)  Bone only3829Visceral only3338Bone + visceral2924Last prior line of therapy included but not limited to (%)  Letrozole4131Anastrozole1219Tamoxifen1214Exemestane122Palbociclib+Fulvestrant07Line (L) of metastatic therapy (%)  1L19222L38433L4335

Enrollment therapy (%): everolimus+exemestane (35), fulvestrant (15), palbociclib + letrozole (15), tamoxifen (14), exemestane (7), palbociclib+fulvestrant (7), letrozole (4) and palbociclib+exemestane (1). Follow-up visits with physician after therapy initiation ET, ET+TT (%): week 2 (5, 47), month 1 (71, 67), month 3 (43, 31). Numerical differences were observed in EORTC QLQ C30 and BR23 global health status/QoL, functional and symptom scale scores between ET and ET+TT cohorts. Mean changes in transformed scores from baseline to month 3 were generally similar between cohorts however 'therapy side effects' symptom item worsened in ET+TT cohort (P = 0.031, Wilcoxon rank sum). Resource utilization in between scheduled visits during 1st 3 months of therapy was similar between cohorts for physician/radiology, hospitalizations and ER visits however patient calls to supportive care nurse was increased in ET+TT cohort (P = 0.008, Fisher's exact). Treatment discontinuation rate (20%) was similar between cohorts with progression as predominant reason for initiating next therapy. Chemotherapy (CT) was the most frequent subsequent therapy and represented 1st line metastatic CT for majority of patients.

Conclusions:

ET+TT patients were younger, had better ECOG, more visceral disease and 60% received everolimus+exemestane with <10% receiving prior CDK4/6 therapy. Half of patients in ET+TT cohort returned for a follow-up visit with oncologist within 2 weeks of therapy initiation (compared to minority in ET cohort) and called the supportive care nurse in between scheduled visits. Patient-reported QoL within 1st 3 months of therapy was generally similar between cohorts. Therapy-related AEs impacted the patient-reported experience in ET+TT cohort however AEs did not lead to therapy discontinuation in over 85% of cases. These results highlight the importance of: (1) proactive AE patient education/management upon ET+TT initiation and at subsequent follow-up visits, (2) week 2 visit and (3) additional nursing telephone support in between visits.

Citation Format: Dent S, Califaretti N, Doyle C, Ferrario C, Chouinard E, Kulkarni S, Roy J-A, Perri SR, Chia S. Treat ER+ight Canadian prospective observational study in HR+ advanced breast cancer: 2nd interim analysis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-15-02.

Abstract P2-02-02: Dynamics of ctDNA changes during neoadjuvant chemotherapy in triple-negative breast cancer patients

Background:

Liquid biopsies to monitor response to treatment are a minimally invasive and highly attractive method for clinical application. Detection of ctDNA in plasma is now highly sensitive thanks to the use of novel highly sensitive and specific techniques such as ddPCR. In the present study we set out to analyze the utility of using ctDNA to monitor response to treatment in patients receiving standard neoadjuvant chemotherapy in triple negative breast cancer.

Methods:

Serial blood was collected from triple negative breast cancer patients participating in the Q-CROC-03 clinical trial (NCT01276899). The trial recruited triple negative breast cancer patients undergoing standard neoadjuvant chemotherapy. Paired biopsies were collected prior and at the end of treatment and serial bloods collected throughout the study. Whole exome sequencing was performed on tissues collected and we identified mutated genes of interest. Cell free DNA (cfDNA) was extracted from 3 ml of plasma and 4-10 variants per patient were analyzed by ddPCR in serial plasma samples collected before and during treatment. Response was measured by evaluating residual cancer burden (RCB), and non-responders were RCBII-III, responders RCB0-I.

Results:

For the present analysis, we identified 60 variants in tumors from 12 patients (9 RCBII-III and 3 RCB0-I). Except for TP53, none of the genes were shared among the tumors. 20% of the variants were not detected in ctDNA at any time point and we did not find any correlation between cfDNA levels and tumor size or response to treatment. The average variant allele frequency (VAF) of all detected variants at baseline was higher in RCBII-III patients than in RCB0-I patients (7.0 vs 0.7 respectively). Interestingly, variants that were detected either only in the pre-chemo tumor or in the post-chemo tumor were frequently detected throughout neoadjuvant therapy, highlighting the ability of ctDNA to capture tumor heterogeneity. In almost all cases, we observed a dramatic decrease in ctDNA VAF after one cycle of chemotherapy, including 30% to non-detectable levels. By the 5th cycle of chemotherapy 97% of detected variants had decreased (average 95% decrease). This decrease in ctDNA VAF was independent of RCB score. In some RCBII-III cases, ctDNA VAF increased prior to surgery, reflecting residual tumor presence.

Conclusion:

ctDNA could be detected in plasma of all early TNBC patients undergoing neoadjuvant chemotherapy with the majority of variants detected in plasma collected at baseline prior to chemotherapy. Once treatment started, the abundance of ctDNA markedly decreased in plasma independently of tumor response. The effect of chemotherapy on levels of ctDNA needs further investigation.

Citation Format: Cavallone L, Adriana A-M, Aldamry M, Lafleur J, Cathy L, Alirezaie N, Bareke E, Majewski J, Ferrario C, Mihalciou C, Roy J-A, Markus E, Robidoux A, Pelmus M, Aleynikova O, Discepola F, Basik M. Dynamics of ctDNA changes during neoadjuvant chemotherapy in triple-negative breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-02.

Questioning the Utility of Pooling Samples in Microarray Experiments with Cell Lines

We describe a microarray experiment using the MCF-7 breast cancer cell line in two different experimental conditions for which the same number of independent pools as the number of individual samples was hybridized on Affymetrix GeneChips. Unexpectedly, when using individual samples, the number of probe sets found to be differentially expressed between treated and untreated cells was about three times greater than that found using pools. These findings indicate that pooling samples in microarray experiments where the biological variability is expected to be small might not be helpful and could even decrease one's ability to identify differentially expressed genes.

Regeneration in Stellate Echinoderms: Crinoidea, Asteroidea and Ophiuroidea

Reparative regeneration is defined as the replacement of lost adult body parts and is a phenomenon widespread yet highly variable among animals. This raises the question of which key cellular and molecular mechanisms have to be implemented in order to efficiently and correctly replace entire body parts in any animal. To address this question, different studies using an integrated cellular and functional genomic approach to study regeneration in stellate echinoderms (crinoids, asteroids and ophiuroids) had been carried out over the last few years. The phylum Echinodermata is recognized for the striking regeneration potential shown by the members of its different clades. Indeed, stellate echinoderms are considered among the most useful and tractable experimental models for carrying comprehensive studies focused on ecological, developmental and evolutionary aspects. Moreover, most of them are tractable in the laboratory and, thus, should allow us to understand the underlying mechanisms, cellular and molecular, which are involved. Here, a comprehensive analysis of the cellular/histological components of the regenerative process in crinoids, asteroids and ophiuroids is described and compared. However, though this knowledge provided us with some clear insights into the global distribution of cell types at different times, it did not explain us how the recruited cells are specified (and from which precursors) over time and where are they located in the animal. The precise answer to these queries needs the incorporation of molecular approaches, both descriptive and functional. Yet, the molecular studies in stellate echinoderms are still limited to characterization of some gene families and protein factors involved in arm regeneration but, at present, have not shed light on most of the basic mechanisms. In this context, further studies are needed specifically to understand the role of regulatory factors and their spatio-temporal deployment in the growing arms. A focus on developing functional tools over the next few years should be of fundamental importance.

Fundamental aspects of arm repair phase in two echinoderm models

Regeneration is a post-embryonic developmental process that ensures complete morphological and functional restoration of lost body parts. The repair phase is a key step for the effectiveness of the subsequent regenerative process: in vertebrates, efficient re-epithelialisation, rapid inflammatory/immune response and post-injury tissue remodelling are fundamental aspects for the success of this phase, their impairment leading to an inhibition or total prevention of regeneration. Among deuterostomes, echinoderms display a unique combination of striking regenerative abilities and diversity of useful experimental models, although still largely unexplored. Therefore, the brittle star Amphiura filiformis and the starfish Echinaster sepositus were here used to comparatively investigate the main repair phase events after injury as well as the presence and expression of immune system and extracellular matrix (i.e. collagen) molecules using both microscopy and molecular tools. Our results showed that emergency reaction and re-epithelialisation are similar in both echinoderm models, being faster and more effective than in mammals. Moreover, in comparison to the latter, both echinoderms showed delayed and less abundant collagen deposition at the wound site (absence of fibrosis). The gene expression patterns of molecules related to the immune response, such as Ese-fib-like (starfishes) and Afi-ficolin (brittle stars), were described for the first time during echinoderm regeneration providing promising starting points to investigate the immune system role in these regeneration models. Overall, the similarities in repair events and timing within the echinoderms and the differences with what has been reported in mammals suggest that effective repair processes in echinoderms play an important role for their subsequent ability to regenerate. Targeted molecular and functional analyses will shed light on the evolution of these abilities in the deuterostomian lineage.

Marine-derived collagen biomaterials from echinoderm connective tissues

The use of marine collagens is a hot topic in the field of tissue engineering. Echinoderms possess unique connective tissues (Mutable Collagenous Tissues, MCTs) which can represent an innovative source of collagen to develop collagen barrier-membranes for Guided Tissue Regeneration (GTR). In the present work we used MCTs from different echinoderm models (sea urchin, starfish and sea cucumber) to produce echinoderm-derived collagen membranes (EDCMs). Commercial membranes for GTR or soluble/reassembled (fibrillar) bovine collagen substrates were used as controls. The three EDCMs were similar among each other in terms of structure and mechanical performances and were much thinner and mechanically more resistant than the commercial membranes. Number of fibroblasts seeded on sea-urchin membranes were comparable to the bovine collagen substrates. Cell morphology on all EDCMs was similar to that of structurally comparable (reassembled) bovine collagen substrates. Overall, echinoderms, and sea urchins particularly, are alternative collagen sources to produce efficient GTR membranes. Sea urchins display a further advantage in terms of eco-sustainability by recycling tissues from food wastes.

The human gut microbiota and its interactive connections to diet

The microbiota of the gastrointestinal tract plays an important role in human health. In addition to their metabolic interactions with dietary constituents, gut bacteria may also be involved in more complex host interactions, such as modulation of the immune system. Furthermore, the composition of the gut microbiota may be important in reducing the risk of contracting particular gut infections. Changes in the microbiota during an individual's lifespan are accompanied by modifications in multiple health parameters, and such observations have prompted intense scientific efforts aiming to understand the complex interactions between the microbiota and its human host, as well as how this may be influenced by diet.

Skeletal regeneration in the brittle star Amphiura filiformis

Background

Brittle stars regenerate their whole arms post-amputation. Amphiura filiformis can now be used for molecular characterization of arm regeneration due to the availability of transcriptomic data. Previous work showed that specific developmental transcription factors known to take part in echinoderm skeletogenesis are expressed during adult arm regeneration in A. filiformis; however, the process of skeleton formation remained poorly understood. Here, we present the results of an in-depth microscopic analysis of skeletal morphogenesis during regeneration, using calcein staining, EdU labeling and in situ hybridization.

Results

To better compare different samples, we propose a staging system for the early A. filiformis arm regeneration stages based on morphological landmarks identifiable in living animals and supported by histological analysis. We show that the calcified spicules forming the endoskeleton first appear very early during regeneration in the dermal layer of regenerates. These spicules then mature into complex skeletal elements of the differentiated arm during late regeneration. The mesenchymal cells in the dermal area express the skeletal marker genes Afi-c-lectin, Afi-p58b and Afi-p19; however, EdU labeling shows that these dermal cells do not proliferate.

Conclusions

A. filiformis arms regenerate through a consistent set of developmental stages using a distalization-intercalation mode, despite variability in regeneration rate. Skeletal elements form in a mesenchymal cell layer that does not proliferate and thus must be supplied from a different source. Our work provides the basis for future cellular and molecular studies of skeleton regeneration in brittle stars.

Electronic supplementary material

The online version of this article (doi:10.1186/s12983-016-0149-x) contains supplementary material, which is available to authorized users.

Abstract OT1-03-15: The METRIC trial: A randomized international study of the antibody-drug conjugate glembatumumab vedotin (GV or CDX-011) in patients with metastatic gpNMB-overexpressing triple-negative breast cancer (TNBC)

Background

Glycoprotein NMB (gpNMB) is an internalizable transmembrane protein overexpressed in approximately 20% of breast cancer (BC), including approximately 40% of TNBC. gpNMB is a poor prognostic marker in BC (Rose CCR 2010) and preclinically has been implicated in tumor invasion, metastasis, and angiogenesis. GV is a novel antibody-drug conjugate targeting the potent cytotoxin monomethylauristatin E (MMAE) to gpNMB overexpressing cancer cells.

In a Phase I/II study and the Phase II "EMERGE" study, GV demonstrated promising activity with TNBC patients (pts) deriving the greatest benefit and exhibiting the highest degree of gpNMB overexpression. GV was well-tolerated with the most frequent treatment-related toxicities consisting of rash, neutropenia, and neuropathy. In subset analyses of the EMERGE trial, objective response rate (ORR) was 30% (7/23) for GV vs. 9% (1/11) for investigator's choice in tumors with gpNMB overexpression (>25% of tumor epithelium); 18% (5/28) vs. 0% (0/11) in TNBC; and 40% (4/10) vs. 0% (0/6) in gpNMB-overexpressing TNBC for GV and IC respectively, with apparent improvements in progression-free survival (PFS; hazard ratio (HR) = 0.11) and overall survival (OS; HR = 0.14).

Trial design

The METRIC Trial (NCT#01997333) is an international (USA, CA, Aus), two-arm phase II study. Pts are randomized 2:1 to GV (1.88 mg/kg IV q 21 days) or capecitabine, a current standard of care for this population (2,500 mg/m2 daily for d1-14, q21 days) until progression or intolerance. Crossover is not permitted.

Eligibility criteria

Key eligibility criteria include: >25% of tumor epithelium gpNMB+ by central immunohistochemistry (IHC) screening of archival tissue; estrogen receptor and progesterone receptor <10% and HER2 negative [0-1+ IHC, or ISH copy number <4.0/ratio <2.0] by local assessment; ECOG 0-1; taxane resistance; anthracycline exposure (if indicated); <2 chemotherapy regimens for advanced BC; measurable disease; no persistent Grade >2 toxicity.

Specific aims

The primary endpoint is PFS per independent, blinded central review committee according to RECIST 1.1. Secondary endpoints are ORR, duration of response, OS, safety, pharmacokinetics and pharmacodynamics. Exploratory endpoints are quality of life and/or cancer-related pain.

Statistical methods and target accrual

The trial has 85% power to detect a PFS HR of 0.64 with two sided α = 0.05. The hypothesized median PFS is 4.0 months for capecitabine and 6.25 months for GV. Target accrual is open for 300 pts.

Citation Format: Melisko M, Yardley DA, Blackwell K, Forero A, Ma C, Montero A, Daniel BR, Wright G, Fehrenbacher L, Chew H, Ferrario C, Nanda R, Seiler Jr M, Guthrie T, Vance K, Ouellette G, He Y, Bagley RG, Zhang J, Vahdat LT. The METRIC trial: A randomized international study of the antibody-drug conjugate glembatumumab vedotin (GV or CDX-011) in patients with metastatic gpNMB-overexpressing triple-negative breast cancer (TNBC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT1-03-15.

Re-growth, morphogenesis, and differentiation during starfish arm regeneration

The red starfish Echinaster sepositus is an excellent model for studying arm regeneration processes following traumatic amputation. The initial repair phase was described in a previous paper in terms of the early cicatrisation phenomena, and tissue and cell involvement. In this work, we attempt to provide a further comprehensive description of the later regenerative stages in this species. Here, we present the results of a detailed microscopic and submicroscopic investigation of the long regenerative phase, which can be subdivided into two subphases: early and advanced regenerative phases. The early regenerative phase (1-6 weeks p.a.) is characterized by tissue rearrangement, morphogenetic processes and initial differentiation events (mainly neurogenesis and skeletogenesis). The advanced regenerative phase (after 6 weeks p.a.) is characterized by further differentiation processes (early myogenesis), and obvious morphogenesis and re-growth of the regenerate. As in other starfish, the regenerative process in E. sepositus is relatively slow in comparison with that of crinoids and many ophiuroids, which is usually interpreted as resulting mainly from size-related aspects and of the more conspicuous involvement of morphallactic processes. Light and electron microscopy analyses suggest that some of the amputated structures, such as muscles, are not able to replace their missing parts by directly re-growing them from the remaining tissues, whereas others tissues, such as the skeleton and the radial nerve cord, appear to undergo direct re-growth. The overall process is in agreement with the distalization-intercalation model proposed by Agata and co-workers. Further experiments are needed to confirm this hypothesis.

Wound repair during arm regeneration in the red starfish Echinaster sepositus

Starfish can regenerate entire arms following their loss by both autotomic and traumatic amputation. Although the overall regenerative process has been studied several times in different asteroid species, there is still a considerable gap of knowledge as far as the detailed aspects of the repair phase at tissue and cellular level are concerned, particularly in post-traumatic regeneration. The present work is focused on the arm regeneration model in the Mediterranean red starfish Echinaster sepositus; to describe the early cellular mechanisms of arm regeneration following traumatic amputation, different microscopy techniques were employed. In E. sepositus, the repair phase was characterized by prompt wound healing by a syncytial network of phagocytes and re-epithelialisation followed by a localized subepidermal oedematous area formation. Scattered and apparently undifferentiated cells, intermixed with numerous phagocytes, were frequently found in the wound area during these first stages of regeneration and extensive dedifferentiation phenomena were seen at the level of the stump, particularly in the muscle bundles. A true localized blastema did not form. Our results confirm that regeneration in asteroids mainly relies on morphallactic processes, consisting in extensive rearrangement of the existing tissues which contribute to the new tissues through cell dedifferentiation, redifferentiation, and/or migration.

The trastuzumab and vinorelbine combination: an alternative to taxane-based chemotherapy for early-stage and locally advanced her2-positive breast cancer

BACKGROUND

Anthracyclines and taxanes have historically constituted the backbone of chemotherapy regimens for patients with breast cancer positive for the human epidermal growth factor receptor 2 (her2). For a subset of patients who categorically refuse alopecia, or for those with a contraindication to those drugs, there is an urgent need to define alternative regimens. Here, we report our institutional experience with trastuzumab and vinorelbine (tv), a combination with good clinical activity and a good side effect profile for patients with her2-positive breast cancer.

METHODS

In a retrospective analysis, outcomes data were extracted for patients receiving tv as their only chemotherapy in the non-metastatic setting at the Jewish General Hospital. For the most part, tv was administered weekly for 6 months, followed by trastuzumab for 6 months.

RESULTS

The analysis identified 46 patients (mean age: 64 years) who received tv between 2003 and 2012 (n = 36 adjuvant, n = 10 neoadjuvant). Of the patients in the adjuvant group, 81% had stage i disease. In the neoadjuvant group, 3 patients experienced a complete pathologic response. Only 1 patient experienced local recurrence after a short course (3 months) of adjuvant tv. Overall survival and breast cancer-specific survival were 94% and 98% respectively at a median 5 years of follow-up. Febrile neutropenia-induced sepsis resulted in the death of 1 patient with significant medical comorbidities; 2 other patients died of comorbidities unrelated to their cancer or treatment. Grades 3 or 4 adverse events included neutropenia (23%), febrile neutropenia (10%), fatigue (2%), and anemia (2%).

CONCLUSIONS

For patients with non-metastatic breast cancer refusing alopecia, or for patients who are not candidates for standard chemotherapy, tv is a reasonable alternative to standard adjuvant chemotherapy.

A real-life experience using panitumumab in chemo-refractory metastatic colorectal cancer patients: a retrospective analysis at the Jewish General Hospital, 2009-2012

BACKGROUND

Panitumumab is a fully human monoclonal antibody, directed against the epidermal growth factor receptor, that was shown to be effective in third-line metastatic colorectal cancer. We performed a retrospective analysis of patients with chemo-refractory non-KRAS-mutated metastatic colorectal cancer, who received panitumumab at the Jewish General Hospital in Montreal, Canada, between 2009 and 2012.

METHODS

This chart review included 44 patients (median age: 60 years; performance status: 0-3), of whom 50% had already received three lines of treatment. The primary endpoint was progression-free survival (pfs). Secondary endpoints were overall survival and safety. Tumour progression was determined by radiologic assessments performed once every 3 months per clinical guidelines or by clinical deterioration as determined by the clinician-investigator.

RESULTS

In our sample, median pfs was 21.86 ± 5.23 weeks (95% confidence interval: 12.9 to 36.9 weeks) and overall survival was 35.14 ± 7.75 weeks (95% confidence interval: 25.6 to 73.4 weeks) with a median of 5 cycles of panitumumab treatment. The most frequently reported toxicities with panitumumab were skin toxicity (16.2% grade 3) and hypomagnesemia (10.8% grade 3). No infusion reactions were reported.

CONCLUSIONS

Despite a small sample size from a single institution, our survival and efficacy data are encouraging and comparable to results obtained from the registration panitumumab trial. Our findings suggest that panitumumab can be effective and tolerable in a real-world setting.

Species-specific DNA probe and development of a quantitative PCR assay for the detection of Morganella morganii

AIMS

To develop a SYBR Green quantitative PCR assay (qPCR) for the specific detection of Morganella morganii, a fish pathogen responsible for the Histamine Fish Poisoning.

METHODS AND RESULTS

A new primer set, amplifying a 179-bp fragment of the 16S rRNA gene, was selected for specificity, and 14 M. morganii strains and 32 non-Morganella strains were evaluated. The melting temperature of 84°C was consistently specific for the amplicon. Two standard curves were constructed: the minimum detection sensitivity was 0·563 pg of pure DNA, corresponding to DNA extracted from nine cells of M. morganii. The qPCR assay was evaluated in experiments with seeded fish samples, and the regression coefficient values were calculated.

CONCLUSIONS

A highly specific and rapid assay was developed for the detection of M. morganii in tuna fish samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

This method represents the first study about the quantification of pathogenic M. morganii in fish products. This approach can be utilized to prevent the presence of this undesirable species in the food chain.