Correlation of SPARC, ER, PR, and HER2 tumor with progression-free survival from a phase II neoadjuvant trial of gemcitabine, epirubicin, and nab-paclitaxel

618

Background: Neoadjuvant combinations of gemcitabine (G), anthracyclines and taxanes have demonstrated substantial activity with pCR rates of 20–25%. Secreted protein acidic rich in cysteine (SPARC) is an albumin binding protein that mediates intratumoral accumulation of nab-paclitaxel (nab-P) via a SPARC-albumin binding activity and is a poor prognostic factor for survival. This study was designed to evaluate the feasibility and safety of a biweekly schedule of neoadjuvant nab paclitaxel (nab-P) with G and epirubicin (E) with SPARC tumor assessments performed in consenting patients (pts). Methods: Eligibility: Clinical T1c-T4d and/or N0–3, M0 breast cancer (T1N0M0 excluded), normal LVEF. ER/PR/HER-2 obtained for all pts. Treatment: neoadjuvant G 2,000 mg/m2, E 50 mg/m2, and nab-P 175 mg/m2 q14 days x 6 cycles followed by surgery. Post operative therapy: G 2,000 mg/m2 and nab-P 220 mg/m2 q14 days x 4 cycles. Myeloid growth factors were mandated with all cycles. Two different antibody reagents were used to probe for SPARC expression of tumoral SPARC and stromal SPARC; level 3 immunohistochemical (IHC) SPARC staining was considered positive. Results: 123 pts enrolled. Pathologic responses are available for 112 pts with 11 unevaluable. 82 pts consented to SPARC tumor testing. Median age 51 (29–72). Median tumor size 4.5 cm. 42% ER-/PR -. 55% clinical T3/T4 and 66% node positive. Pathologic complete responses (pCR) were noted in 22 pts (18%) with PRs in 84 pts (68%), and 6 SD (5%). SPARC IHC staining was available in 77 tumor samples; SPARC positivity was noted in 89% of evaluated tumors achieving pCR. Triple negative, ER negative or PR negative tumors were associated with worse PFS. SPARC + tumors showed a trend to improved PFS that was strongly associated with tumoral SPARC but not stromal SPARC. Conclusions: Dose dense neoadjuvant G, E, and nab-P is active and well tolerated with a favorable pCR rate of 20%. ER neg, PR neg, and triple negative tumors were associated with worse PFS. Despite literature reports of SPARC positivity associated with poor prognosis, SPARC+ tumors in this study showed a high concordance with tumor response and a trend to improved PFS with tumoral SPARC.

[Table: see text]

Characterization of triple-negative breast cancer utilizing microarray-based gene-expression profiling

e22014

Background: Triple-negative breast cancer (TNBC) is characterized by lack of expression of estrogen receptor (ER), progesterone receptor (PR) and HER-2. This makes it one of the most challenging subgroups for clinical decision-making. Methods: We analyzed gene-expression profiles of 200 node-negative breast cancer patients utilizing the Affymetrix HG-U133A array. After performing an unsupervised hierarchical cluster analysis using 2579 genes selected for variable expression within our dataset, we constructed metagenes for five dominant cluster (basal-like, luminal, proliferation, T-cell, B-cell). The interrelation of the median expression of these metagenes between TNBC and those cancer specimens expressing at least one of those receptors was analysed with the Wilcoxon-Mann-Whitney test. An intrinsic gene list was used to define basal-like breast cancer (BLBC). Sensitivity and specificity of TNBC to correctly classify BLBC was calculated. Metastasis-free survival (MFS) at 5 years was calculated according to Kaplan Meier. Results: Of the 200 node-negative breast cancer patients, 33 (16.5%) were triple-negative and 20 (10%) basal-like. Sensitivity of TNBC to correctly predict BLBC was 100%, specificity was 93.1%. TNBC showed an overexpression of the basal-like metagene (P=7.905e-13), an inverse relation with the luminal metagene (p=1.151e-12) and had higher proliferation and higher expression of T-cell (P=6.316e-5) and B-cell (P=3.551e-6) metagene. A higher expression of the B-cell metagene was associated with longer MFS in both TNBC (P=0.048) and BLBC (P=0.041). Conclusions: Characterization of TNBC reveals marked differences in gene-expression. Overexpression of mRNA transcripts related to the humoral immune system might serve as a protective factor in this particular subgroup.

No significant financial relationships to disclose.

Preliminary progression free survival and SPARC tumor correlatives from a phase II neoadjuvant trial of gemcitabine, epirubicin, and nab paclitaxel

Abstract #5116

Background: Neoadjuvant combinations of gemcitabine (G), anthracyclines and taxanes have demonstrated significant activity with pCR rates of 20-25% albeit with significant myelosuppression. Secreted protein acidic rich in cysteine (SPARC) is an albumin binding protein that mediates intratumoral accumulation of nab-paclitaxel (nab-P) via a SPARC-albumin specific binding activity. This study was designed to evaluate a biweekly schedule of neoadjuvant nab paclitaxel (nab-P) with gemcitabine and epirubicin (E). SPARC tumor assessments were performed in consenting patients (pts) with subsequent pathologic and survival correlatives.
 Methods: Eligibility: Clinical T1c-T4d and/or N0-3, M0 breast cancer (T1N0M0 excluded), ECOG PS 0-2, normal LVEF. ER/PR/HER2 obtained for all pts. Treatment: 6 cycles neoadjuvant G 2000 mg/m2, E 50 mg/m2, and nab-P 175 mg/m2 q14 days followed by surgery. Post operative therapy: 4 cycles G 2000 mg/m2 and nab-P 220 mg/m2 q14 days. Myeloid growth factors were mandated with all cycles. 2 antibody reagents were used to probe for SPARC expressions. For this study, level 3 immunohistochemical (IHC) SPARC staining was considered positive. Results: 123 pts have enrolled with pathologic responses available for 106. 82 pts consented to SPARC testing. Median age 51 (29-72). Median tumor size 4.5 cm. Histology: 81% ductal, 10% lobular, 9% other. 42% ER and PR negative. 55% clinical T3/T4 and 66% lymph node positive at presentation. G3/4 toxicity present in >5% of pts: neutropenia 16% (febrile neutropenia 1 pt), thrombocytopenia 9% with arthralgias 11%, fatigue 10%, and infection 7%. 20 pts did not complete study treatment for the following reasons: disease progression 7, toxicity 3, pt/MD request 5, and other 5. pCR was noted in 23 pts (22%) with PRs in 76 pts (71%), and 6 SD. SPARC IHC staining was available for 76 tumors. SPARC level 3 IHC staining was noted in 65 tumors (86%); 65% were associated with a PR or pCR. Median PFS was 23 months and overall survival at 24 months is 77%. Pts who relapsed ≤16 months from diagnosis were more likely to be triple negative (p = 0.04), or ER negative (p = 0.001), or PR negative (p = 0.0006). Conclusions: Neoadjuvant dose dense GEA is active and better tolerated than other gemcitabine/anthracycline/taxane combinations. The pCR rate of 22% compares favorably with other comparable neoadjuvant regimens albeit with minimal toxicity. Pts with early relapse defined as ≤16 months from diagnosis were more likely to demonstrate a triple negative phenotype or demonstrate estrogen or progesterone receptor negativity. SPARC tumor correlatives with progression free and overall survival are on ongoing and will be presented.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5116.

Correlation of contrast-enhanced MR images with the histopathology of minimally invasive thermal and cryoablation cancer treatments in normal dog prostates

Magnetic Resonance Imaging (MRI) is a promising tool for visualizing the delivery of minimally invasive cancer treatments such as high intensity ultrasound (HUS) and cryoablation. We use an acute dog prostate model to correlate lesion histopathology with contrast-enhanced (CE) T1 weighted MR images, to aid the radiologists in real time interpretation of in vivo lesion boundaries and pre-existing lesions. Following thermal or cryo treatments, prostate glands are removed, sliced, stained with the vital dye triphenyl tetrazolium chloride, photographed, fixed and processed in oversized blocks for routine microscopy. Slides are scanned by Trestle Corporation at .32 microns/pixel resolution, the various lesions traced using annotation software, and digital images compared to CE MR images. Histologically, HUS results in discrete lesions characterized by a "heat-fixed" zone, in which glands subjected to the highest temperatures are minimally altered, surrounded by a rim or "transition zone" composed of severely fragmented, necrotic glands, interstitial edema and vascular congestion. The "heat-fixed" zone is non-enhancing on CE MRI while the "transition zone" appears as a bright, enhancing rim. Likewise, the CE MR images for cryo lesions appear similar to thermally induced lesions, yet the histopathology is significantly different. Glands subjected to prolonged freezing appear totally disrupted, coagulated and hemorrhagic, while less intensely frozen glands along the lesion edge are partially fragmented and contain apoptotic cells. In conclusion, thermal and cryo-induced lesions, as well as certain pre-existing lesions (cystic hyperplasia - non-enhancing, chronic prostatitis - enhancing) have particular MRI profiles, useful for treatment and diagnostic purposes.

Operationalizing the concept of resilience in child neglect: case study research

BACKGROUND

There is a considerable amount of interest in resilience as a concept for child care and protection practice. This paper describes an exploratory project that drew on a set of case studies to explore the extent to which the concept of resilience can be operationalized for use with neglected children in the context of statutory social work.

METHOD

The study was carried out within a local authority in Scotland and focused on the value of the concept as an aid to assessment and planning. The study built on a published workbook that provides a structure for the assessment of potential areas of resilience and gives detailed suggestions for intervention in six domains of a child's life. Eight neglected children aged between five and 11 were recruited. Six training days on the concept were held. Questionnaires were used to gather information about the theoretical frameworks already being used. At the end of the study, semi-structured interviews were carried out with the social workers about the value of the concept. Assessment reports completed before and after the training were analysed.

RESULTS

Findings indicated that participants were familiar with the concept of resilience and that the training helped enhance their understanding of the concept. Training assisted with the provision of a more structured approach to assessment and planning. Respondents reported that the approach enhanced their knowledge of the child and they were able to identify areas for development in the six domains.

CONCLUSION

The study indicated that the concept of resilience can be operationalized for use with neglected children. Further, the case studies raised the issue of the extent to which the need for a secure base underpins other domains. The domain of positive values was also highlighted as an important area for further exploration.

Mapping of the prostate in endorectal coil-based MRI/MRSI and CT: A deformable registration and validation study

The endorectal coil is being increasingly used in magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) to obtain anatomic and metabolic images of the prostate with high signal-to-noise ratio (SNR). In practice, however, the use of endorectal probe inevitably distorts the prostate and other soft tissue organs, making the analysis and the use of the acquired image data in treatment planning difficult. The purpose of this work is to develop a deformable image registration algorithm to map the MRI/MRSI information obtained using an endorectal probe onto CT images and to verify the accuracy of the registration by phantom and patient studies. A mapping procedure involved using a thin plate spline (TPS) transformation was implemented to establish voxel-to-voxel correspondence between a reference image and a floating image with deformation. An elastic phantom with a number of implanted fiducial markers was designed for the validation of the quality of the registration. Radiographic images of the phantom were obtained before and after a series of intentionally introduced distortions. After mapping the distorted phantom to the original one, the displacements of the implanted markers were measured with respect to their ideal positions and the mean error was calculated. In patient studies, CT images of three prostate patients were acquired, followed by 3 Tesla (3 T) MR images with a rigid endorectal coil. Registration quality was estimated by the centroid position displacement and image coincidence index (CI). Phantom and patient studies show that TPS-based registration has achieved significantly higher accuracy than the previously reported method based on a rigid-body transformation and scaling. The technique should be useful to map the MR spectroscopic dataset acquired with ER probe onto the treatment planning CT dataset to guide radiotherapy planning.