bluuebunny/crossref_metadata_2025 huggingface dataset:
Perioperative sunitinib dosing around extensive resections of imatinib-resistant metastatic gastrointestinal stromal tumors
Authors: Raut C. P. , Morgan J. A. , Quigley M. T. , George S. , Wagner A. J. , Demetri G. D. , Bertagnolli M. M.
Published: March 2020

10044

Background: Sunitinib malate (SU) is the primary therapy for metastatic gastrointestinal stromal tumor (GIST) resistant to imatinib mesylate (IM). Its inhibition of multiple receptor tyrosine kinases (TK) raised concerns that SU may impair healing after cytoreductive procedures more than IM. We reviewed our experience to compare the spectrum of postoperative complications after SU v. IM therapy. Methods: All patients (pts) with IM-resistant metastatic GISTs enrolled in phase II/III SU protocols at our institution were reviewed. The control group underwent cytoreduction on IM. Perioperative SU dosing and complications after surgery and after resumption of SU were recorded. Complications related to healing included wound/fascial dehiscence, anastomotic leak, and fistula. Complications not attributed to wound healing included hemorrhage, abscess, seroma, and ileus. Results: We treated 188 pts with IM-resistant metastatic GISTs with SU. Twenty-six pts on SU and 46 pts on IM underwent 28 and 53 operations for disease resection, respectively ( Table ). SU was stopped a median of 5 days (range 0–26) prior to surgery and resumed a median of 33 days (range 12–183) after surgery and 20 days (range 7- 178) after hospital discharge, generally during the first postoperative clinic visit. There were 17 complications after 14 (50%) of 28 procedures on SU and 23 complications after 20 (38%) of 53 procedures on IM (p=NS). Dehiscence, leaks, or fistulas, were identified after 2 (7%) procedures on SU and 4 (8%) procedures on IM (p=NS). These 2 pts with complications on SU stopped the drug 9 and 22 days prior to surgery. No wound healing complications were noted among the 18 pts who stopped SU less than 9 days before surgery. Conclusions: Wound healing complications were not more common after extensive resections on SU than on IM, despite SU's inhibition of a wider spectrum of TKs. Our current practice is to continue SU until 1–2 days prior to surgery and to resume SU at the first postoperative visit.

[Table: see text]

No significant financial relationships to disclose.
Pathological significance of deletions involving codons 557 and 558 of KIT gene in localized resected gastrointestinal stromal tumors (GIST) of intermediate and high risk: A study by the Spanish Group for Sarcoma Research (GEIS)
Authors: Romero I. , Poveda A. , Martin J. , Lopez-Pousa A. , Gomez C. , Safont M. , Andres R. , Guillem V. , Llombart-Bosch A. , Lopez-Guerrero J.
Published: March 2020

10051

Background: Approximately 60 to 85% of GISTs harbour activating mutations of the KIT or PDGFRA tyrosine kinase genes. Deletions affecting codons 557–558 of KIT are relevant to prognosis of resected GIST (Martin J, et al. J Clin Oncol. 2005, 23:6190). Methods: GIST of high or intermediate malignant risk according to Fletcher classification (Hum Pathol. 2002;33; 459) with a complete (R0) or microscopic residual (R1) resection were prospectively evaluated. Central pathology review was carried out. The mutational analysis of exons 9, 11, 13 and 17 of KIT and exons 12 and 18 of PDGFRA was undertaken from DNA extracted from paraffin-embedded tissue. The purpose of this study was to explore the correlation between deletion mutation involving 557–558 codons within KIT gene and known prognostic factors in GIST: mitotic count and size. Results: Of the 33 GIST, 19 were gastric, 13 of small bowell and one of other location. Median tumor size was 10.4 cm (1.9–22 cm), and median mitotic count was 2 (1–32). All cases showed an immunostaining with diffuse cytoplasmic pattern of c-kit (CD117). An 82% (27) presented either a KIT (23) or a PDGFRA (4) mutation. Eleven deletions affecting codons 557–558 of KIT were observed. KIT mutations were associated to spindle type histology and PDGFRA mutations to epithelioid histology. No statistical association between tumor size and KIT mutations, including patients with deletions 557–558, was found. Tumors carrying a deletion of codons 557–558 of KIT presented a different median of mitotic count (8 mit × 50 hpf) than the rest (2 mit × 50 hpf), this difference was statistically significant (p = 0,029) in the Mann-Whitney U test. Conclusions: Deletions affecting codons 557–558 of KIT define a group of cases with a high proliferative potential. The prognostic and predictive significance of these findings are waiting for a longer follow-up.

No significant financial relationships to disclose.
Loss of CXCR4 nuclear immunoreactivity in synovial sarcoma (SS) correlates with poor survival
Authors: Grisanti S. , Facchetti F. , Dei Tos A. P. , Rossi E. , Ardighieri L. , Ferrari V. D. , Amoroso V. , Bercich L. , Ippolito V. , Marini G.
Published: March 2020

10069

Background: The chemokine receptor CXCR4 has been found to be expressed in mesenchymal neoplasms including osteosarcoma, rhabdomyosarcoma, Ewing's sarcoma and SS. Gene products of the HER oncogenic family, such as EGFR and HER2, have been described to be overexpressed in SS and we previously demonstrated coexpression of CXCR4 and EGFR but not HER2 in SS patients. In this study we analysed CXCR4 expression in terms of subcellular localization and extended results to 15 SS patients. Methods: Fifteen SS patients were included in the study. In all cases morphological diagnoses were confirmed molecularly by FISH or RT-PCR specific for t(X;18). HER2 and EGFR expression were determined by immunohistochemistry (IHC) while HER2 gene status was assessed by FISH analysis. CXCR4 expression was determined with an anti-human CXCR4 monoclonal antibody (Clone 44716, R&D Systems, Minneapolis, USA) followed by incubation with the EnVision peroxidase kit (Dakocytomation, Glostrup, Denmark). CXCR4 nuclear vs cytoplasmic expression was correlated with outcome. Results: In all samples IHC analysis for HER2 was negative and no amplification was found by FISH. EGFR expression was observed in 13/15 patients. CXCR4 immunoreactivity was identified in 9/15 cases. CXCR4 and EGFR were coexpressed in 8/15 tumors. Follow-up ranged from 9 to 127 months. After a median follow-up of 39 months, 7 patients were dead of SS, 8 patients were alive (7 of them are disease-free and one has evident disease in the retroperitoneum). All alive and disease-free patients showed nuclear CXCR4 expression whereas 6/7 dead patients expressed cytoplasmic or membrane CXCR4 (p = 0.0008). Conclusions: Loss of nuclear CXCR4 expression is associated with fatal course and may represent a novel prognostic factor. CXCR4 is frequently coexpressed with EGFR but not with HER2. In contrast with previous reports HER2 seems not involved in the carcinogenesis of SS.

No significant financial relationships to disclose.
A gene expression signature of eventual brain metastases in patients with breast cancer
Authors: Tham Y. , Creighton C. , Gutierrez C. , Osborne C. K. , Brown P. , Chang J. C.
Published: March 2020

1019

Background: The incidence of brain metastases (BM) from breast cancer may be increasing, in part due to more effective systemic therapy. A metastatic signature of bone or lung metastases has been identified in mice but not for BM in human. We hypothesized that gene expression patterns of primary breast cancers may provide a specific metastatic signature for eventual BM. Methods: Core biopsies from primary breast cancers of 11 patients with BM and 12 patients who have other non-brain metastases were identified. Double- stranded cDNA was synthesized using an oligo-dT primer containing a T7 RNA polymerase promoter, followed by in vitro transcription with biotinylated ribonucleotides. The labeled cRNA was hybridized to Affymetrix U133-A chips. Results: Of the patients with BM, 55% were ER negative/HER-2 positive while 36% were ER positive/HER-2 negative. Of the patients with non brain metastases, 42% were ER negative/HER-2 positive and 50% were ER positive/HER-2 negative, with. A differential pattern of gene expression was seen in primary tumors of patients with BM when compared with those who had non-brain metastases. Many more genes were found elevated in patients with BM over what would be expected by chance (after correcting for multiple testing). Tumors that developed BM had expression of genes related to the neurological development pathways such as fetal Alzheimer antigen, MAD, neuropilin 1, and others. Several kinase pathways were involved such as protein kinase C and casein kinase substrate in neurons 2, and A kinase (PRKA) anchor protein 13. These genes will be validated in an independent set of patients with BM and non-brain metastases using real time PCR. Conclusions: The identification of genes that may predict for future development of brain metastases has many implications in terms of screening or prophylactic treatment. This would also help identify potential targets for the treatment of brain metastases.

No significant financial relationships to disclose.
A quality-adjusted time without symptoms or toxicity (Q-TWiST) analysis comparing lapatinib plus capecitabine compared to capecitabine for metastatic breast cancer (MBC)
Authors: Sherrill B. , Allshouse A. , Amonkar M. , Stein S.
Published: March 2020

1026

Background: Data for this analysis is from a Phase III randomized study that was stopped early by the IDMC since a planned interim analysis demonstrated the primary endpoint had been achieved i.e. longer time to disease progression for patients taking lapatinib plus capecitabine (L+C) versus capecitabine (C) alone. The study included women with refractory advanced or ErbB2+ MBC who had received prior therapy which included anthracyclines, taxanes and trastumuzab. The Q-TWiST method was used to compare the trade-off between toxicities and delayed progression. Methods: The area under overall survival curves for each treatment group was partitioned into three health states: toxicity (TOX), time without toxicity or disease progression (TWiST), and the period until death or end of follow-up following disease progression (REL). TOX is time spent with grade ¾ adverse events (AEs) during progression-free survival (PFS) time. TWiST is the remaining time prior to progression in which no serious AEs were experienced. The utility-weighted sum of the mean health state durations was derived and treatment comparisons of Q-TWiST were made at varying combinations of the utility weights using a threshold utility analysis. Results: The ITT population included 399 subjects ages 26–83 [L+C group N=198, C group N=201]. Overall median survival was 67 weeks based on data through 3APR2006. There was not a significant difference between groups in mean duration of serious AEs prior to progression. (L+C 1.7 weeks, C 1.5 weeks). Using utility weights of 0.5 for both TOX and REL, i.e. counting 2 days of TOX or REL as 1 day of TWiST, resulted in a 7-week difference in quality-adjusted survival favoring L+C (p = 0.0013). The Q-TWiST difference was significant across an entire matrix of possible utility weights. Results were robust in sensitivity analyses including all AEs. An observed-utility analysis based on EQ-5D scores is in progress. Conclusions: The longer time to disease progression with L+C versus C was achieved without increased time with serious AEs, resulting in more quality-adjusted survival for patients.

No significant financial relationships to disclose.
A report of cardiac events in a phase II clinical study using trastuzumab combined with pertuzumab in HER2-positive metastatic breast cancer (MBC)
Authors: Portera C. C. , Walshe J. M. , Denduluri N. , Berman A. W. , Vatas U. , Rosing D. R. , Chow C. K. , Swain S. M.
Published: March 2020

1028

Background: T and P are humanized recombinant monoclonal antibodies (MoAB) that target different epitopes of HER2 extracellular domain. P blocks HER2’s ability to heterodimerize with other HER/ErbB receptors. Methods: This Ph II trial evaluates the efficacy and safety of T with P in patients (pts) with HER2+ (FISH +) MBC who had progressive disease (PD) on T-based therapy. Eligible pts must have had = 3 T-based regimens, normal (nl) left ventricular ejection fraction (EF=55%) and without significant cardiac history. Pts received IV T (6mg/kg) and P (420 mg) every 3 weeks (wks). EKG plus echocardiogram (ECHO) or cardiac MRI and tumor response were assessed every 3 and 6 wks, respectively. Results: Eleven pts received 39 (1 to 13) cycles, 1 pt achieved a partial response (PR) and 3 pts had stable disease. A total of 68 ECHOs and 8 cardiac MRIs were performed. Left ventricular systolic dysfunction (LVSD) with nl EKG was seen in 5 pts; Grade (Gr) 1 (n = 2) (EF 50–55%), Gr 2 (n = 2) (EF 40–50%) and Gr 3 (n = 1) (EF20–40%). Gr 2–3 events were associated with global hypokinesis. Gr 3 event was associated with symptomatic CHF. All 5 pts had received 240mg/m2 cumulative dose of doxorubicin, 2 pts (Gr 2–3) received chest wall radiation, and 1 pt (Gr 1) had HTN. Two pts with Gr 1–2 LVSD had a history of reduced EF during prior T-based treatment, which reversed to nl upon stopping T. Reduced EF appeared within 1–2 cycles, which returned to nl in 3 pts within 1wk to 3 months (mo) post discontinuing T/P. One pt had persistent Gr 2 LVSD 3 mo after the initial event. The pt with Gr 3 LVSD had extensive chest wall disease and died of PD and possibly CHF 2 mo after treatment termination. Conclusions: We observed Gr 1–3 LVSD in patients with HER2+ MBC who received dual MoAB treatment directed at HER2, in which very strict cardiac surveillance guidelines were required. One of 11 pts achieved PR and 1 pt had symptomatic CHF thus far. It is unknown whether the other events would have become symptomatic if treatment had continued. Further evaluation of the efficacy of combination T with P is required to define the overall risk and benefit.

No significant financial relationships to disclose.
Breast cancer liver metastases (BCLM): What may be the role of surgery combined with chemotherapy?
Authors: Adam R. , Salmon R. , Elias D. , Rivoire M. , Cherqui D. , Jaeck D. , Gigot J. , Le Treut P. , Mantion G. , Belghiti J.
Published: March 2020

1039

Background: Despite recent treatment improvements, the prognosis of BCLM is still poor. Hepatic resection (HR) has been associated with better outcome in selected patients, but its place in multimodality treatment of BCLM remains controversial. This study aimed to examine the outcome of a large cohort of patients selected for HR of BCLM and to define prognostic factors of survival, in a way to better define the place of surgery. Methods: A standardized questionnaire reviewing the main diagnostic and treatment modalities of primary tumor, liver metastases, response to medical therapies, type of surgical procedures, postoperative outcome, and survival following surgery, was sent to all contributing centers. Results: 460 patients treated with liver resection for BCLM from 1980 to 2000, were collected from 31 hepatobiliary surgery centers. Mean age was 51.8 years. Primary tumor, mainly adenocarcinoma, was treated by resection combined with chemotherapy and/or radiotherapy in most cases. Diagnosis of BCLM was made after an average of 54 months from the treatment of the primary tumor. BCLM were unique in 56% and associated to limited extrahepatic disease in 18.5% of patients. After initial treatment by systemic therapy (70% of patients), HR achieved a R0 resection in 82% of patients and was combined to extrahepatic resection for distant metastases in 9% of patients. Postoperative mortality (= 2 months) was 0.2%. Median survival was 45.4 months after HR, with an overall survival of 41% and 22% at 5 and 10 years, respectively. Disease-free survival rates were 14% and 10%, respectively. Four predictive factors were independently associated to an unfavourable outcome: tumor progression on chemotherapy before surgery (p = 0.0006, RR = 2.9), disease-free interval < 12 months after treatment of the primary tumor (p = 0.0003, RR = 2.1), extrahepatic metastases (p = 0.0002, RR = 1.9) and R2 liver resection (p < 0.0001, RR = 3.0). Conclusions: Inclusion of HR in the multimodality treatment of BCLM is safe and associated with a hope of long term survival (22% at 10 years). Surgery should be discussed on a multidisciplinary basis, particularly when potentially radical, in patients well controlled by chemotherapy with a long disease-free interval, and in the absence of extrahepatic disease.

No significant financial relationships to disclose.
Identification of proteins promoting development of metastatic breast tumors
Authors: Seeley E. , Ellsworth R. E. , Ellsworth D. , Sanders M. , Hooke J. A. , Caprioli R. , Shriver C. D.
Published: March 2020

1041

Background: Primary breast tumors are constantly shedding tumor cells into the circulatory and lymphatic systems. Although detection of occult tumor cells is a risk factor for recurrence and progression, tumor cells remain detectable years after initial diagnosis in patients without clinical or histological detection of metastasis. Thus the question remains as to why some women with circulating tumor cells develop metastatic breast cancer while others do not. Methods: Negative lymph nodes from women with node negative (n=22) and node positive disease (n=36) were obtained from patients enrolled in the Clinical Breast Care Project. Negative lymph node status was confirmed by IHC analysis. Frozen tissues were sectioned and mounted on gold coated MALDI target plates for protein expression profiling. Hematoxylin and eosin (H&E) stained slides were prepared from serial sections for histological characterization. MALDI matrix was deposited as individual spots on the tissue sections in a histology directed manner to assay specific areas and tissue types of interest. Mass spectral data were then acquired from multiple sites across each tissue section. Results: 131 features were observed in negative nodes from patients without metastatic disease and 129 in negative nodes from patients with lymph node metastases. While the majority of features detected were similar between the two groups, 8.5% were differentially expressed. Two of the features which were expressed at significantly higher levels in nodes from patients with metastatic disease have been putatively identified as thymosin β4 and thymosin β10. Conclusions: Thymosin β4 and 10 have been associated with disease progression and metastatic capacity in a number of tumor types. The overexpression of these proteins in tumor-negative nodes from patients with metastatic disease in other regional nodes suggests lymph nodes do not play a passive role in metastasis, rather, expression of a specific subset of proteins creates an hospitable environment to facilitate colonization. These markers of metastasis may permit molecular discrimination of those patients with indolent disease from those at risk for metastasis and will thus allow for the design of customized treatment regimens to more effectively treat, or prevent, metastatic spread.

No significant financial relationships to disclose.
Alterations in calcium metabolism in patients on long-term bisphosphonate therapy for metastatic breast cancer (MBC): A potential therapeutic target?
Authors: Simmons C. , Dranitsaris G. , Clemons M. , Wong B. Y. , Veith R. , Cole D. E.
Published: March 2020

1044

Background: The effect of long-term potent BP use on calcium homeostasis in MBC pts is poorly understood. These effects and the need for calcium and Vitamin D supplementation may have significant implications for pt management in both the metastatic and adjuvant settings. Methods: We evaluated serum calcium (sCa), PTH, and 25(OH)D levels and their inter-relationships in 30 MBC pts after prolonged BP use for bone metastases (BM), compared with a control group (CG) of 1484 normal women without bone or mineral disease (JCEM 2003;88:185). The MBC pts were prescribed oral calcium (1g/d) and vitamin D (400IU/d) for 1 month prior to analysis. To determine whether MBC pts differed from CG with respect to the sCa-PTH correlation, logistic regression was performed with sCa, log-transformed PTH and an interaction term (Ca × lnPTH). Results: Mean age of the two groups did not differ [MBC group (58.5 ± 2.0 yr) vs. CG (55.2 ± 0.4 yr, p >.05)]. VitD-deficiency (25vitD < 40 nM) was equally prevalent in the two groups [MBC (23%) vs. CG (25%)]. sCa was significantly higher in MBC pts (2.473 ± 0.019 mM) compared to CG (2.377 ± 0.003, p <0.001). However, PTH was not decreased in MBC pts (4.60 ± 0.36 pM), compared to CG (4.56 ± 0.06, t-test, p=0.91). Logistic regression was highly significant (p<0.0001), as were coefficients for both explanatory variables (sCa, p <0.0001 and lnPTH, p = 0.009) and their interaction (p=0.011). Conclusion: In pts with BM and prolonged BP use there appears to be a shift in the calcium set-point such that PTH release is activated by higher levels of sCa than in controls. We are currently studying whether prophylaxis for relative vit D deficiency in this population can not only correct this shift but also improve pt symptoms

No significant financial relationships to disclose.
NCCTG phase II trial N0531of weekly nab-paclitaxel (nab-p) in combination with gemcitabine (gem) in patients with metastatic breast cancer (MBC)
Authors: Roy V. , LaPlant B. R. , Gross G. G. , Bane C. L. , Palmieri F. M. , Perez E. A.
Published: March 2020

1048

Background: Previous trials with p plus gem show significant antitumor activity in MBC. Nab-p has lower toxicity compared to p with similar therapeutic effects. This study assessed proportion of confirmed tumor responses and toxicity profile of this combination. Methods: Single stage phase II study enrolled patients (pts) with measurable MBC eligible for 1st line chemotherapy (chemo). Pts treated (tx) with nab-p 125 mg/m2 followed by gem 1,000 mg/m2 days 1 and 8 of 21 day cycle. Dose modifications allowed for both drugs. Primary endpoint was proportion of confirmed responses; complete response (CR), partial response (PR) by RESIST criteria on two consecutive evaluations at least 6 weeks apart. 41 evaluable pts required to test the null hypothesis that the confirmed response rate was at most 40% against the alternative of at least 60%. Results: 50 pts enrolled 11/05 to 5/06. Median age 56 (29–86). 40 pts (80%) visceral disease, 34 (68%) ER positive, 28 (56%) PR positive, 1 (2%) HER2 positive, 1 (2%) prior trastuzumab treatment (tx). 25 (50%) had prior adjuvant chemo, including 15 (30%) prior taxane. Median follow-up 7 mos (3–12). Median of 6 cycles of tx completed (1–15). 41 pts discontinued tx, due to progression (41%), pt refusal (27%), adverse events (17%), alternate tx (7%). Confirmed response rate 48% (95% CI: 34–63%): 4 CR, 20 PR. Median duration of response 6.6 mos (95% CI: 5.7, not reached), median progression-free survival (PFS) 7.9 mos (95% CI: 5.3–9.3). Rate of overall survival (OS) at 6 mos 91% (95% CI: 84–100%), 6 month PFS 58% (95% CI: 45–74%). Median OS not reached. 30 pts required dose delays on total of 52 cycles, mostly due to hematologic AEs. 9 pts (19%) had grade (gr) 4 adverse event (AE), 32 (67%) had maximum gr 3 AE. Most common gr 3/4 AEs: neutropenia (52%), fatigue (26%), anemia (14%), dyspnea (14%), thrombocytopenia (12%). Four pts had gr 3 neuropathy. Conclusions: Nab-paclitaxel in combination with gem has clear activity in patients with MBC. Manageable hematologic, but no other significant toxicities. Study ongoing to correlate efficacy with caveolin-1 levels with results expected Spring 2007. Follow up study of this combination with an anti-angiogenesis agent is in development.

No significant financial relationships to disclose.
Preclinical testing of a novel regimen of capecitabine (C) in combination with bevacizumab (B) and trastuzumab (T) in a breast cancer xenograft model
Authors: Traina T. A. , Higgins B. , Theodoulou M. , Dugan U. , Kolinsky K. , Zhang Y. , Heimbrook D. , Packman K. , Hudis C. , Norton L.
Published: March 2020

1049

Background: Mathematical methods applied to xenograft breast cancer models have determined that the maximum impact of C therapy occurs after ∼7 days (7d) of treatment (Norton AACR 2005). The model predicts that doses of C beyond 7d will contribute to toxicity without additional antitumor benefit. The tolerability and anti-tumor activity of C 7d on/7d off (7/7) in female nude mice bearing KPL-4 breast cancer xenografts has been established (SABCS 2006). We now report preclinical models of C7/7 with targeted therapies. Methods: We evaluated the tumor growth inhibition (TGI%) and increase in life span (ILS%) of C7/7 and B with or without T in female nude mice bearing KPL-4, HER2+ breast cancer xenografts. C at maximum tolerated dose (MTD) and ½MTD were tested in combination with conventional doses of the antibodies. Results: C7/7 at MTD is well tolerated in combination with conventional dose B + T. No toxicity was observed at any dose level. The addition of B ± T to C7/7 monotherapy significantly improves TGI%. Survival is significantly prolonged for the combination of C7/7 MTD with B ± T. Comparative results for C7/7 at MTD and ½ MTD are shown in the Table . Additional comparative data will be shown at the meeting. Assessment of ILS% is ongoing for the triplet C7/7 + B + T but has exceeded 463% and >152 days. Conclusions: The improvement in response and survival shown here supports the study of combination C7/7 with B and T. Combinations with B and anti-HER2 therapy will be tested in the clinical, Phase II program at MSKCC.

[Table: see text]

[Table: see text]
Monitoring tumor response to ZD4190 therapy with an 18F labeled angiogenesis imaging agent
Authors: Morrison M. S. , Ricketts S. , Barnett J. , Constantinou M. , Tessier J. , Wedge S. R.
Published: March 2020

10507

Background: While a number of novel therapies are being developed to inhibit the growth or survival of tumor vasculature, there are limited methods available for measuring changes in tumor vascularity. In order to quantify tumour vascularity by PET imaging, we examined an 18F-radiolabeled small peptide (AH111585) containing an RGD (Arg-Gly-Asp) sequence. This peptide binds with high affinity (nM) to avβ3 integrin, a cell adhesion receptor that is highly expressed on tumor neovasculature, but expressed at low levels on mature endothelium and epithelial cells. 18F-AH111585 was used to examine the response of human lung tumor xenografts to treatment with ZD4190, a small molecule inhibitor of VEGF signaling. Methods: MicroPET (using 18F-AH111585) and microCT imaging data was acquired pre and post 3 doses of ZD4190 (100 mg/kg, p.o., over 3 days) or vehicle in CD-1 nude mice bearing Calu-6 tumor xenografts. 18F-AH111585 was administered 2 h prior to microPET imaging (10 min) to allow for tumor uptake and background tissue clearance. Tumor and background tissue uptake was determined from the images (expressed as %id/g). Results: Uptake of 18F-AH111585 in Calu-6 tumors was reduced following 3 doses of ZD4190, with an average reduction of 31.8 ± 4.6 % (calculated from imaging ROI data), whereas increased 18F-AH111585 uptake was observed in tumors of vehicle treated mice (average increase of 26.9 ± 9.4 %). The difference between treated and control group uptake was statistically significant (P<0.01; two- tailed t-test). Tumor size (assessed via caliper measurement) remained comparable over the duration of treatment. Skeletal muscle, used as a reference tissue for ROI analysis, demonstrated equivalent uptake pre and post therapy. Conclusions: The data demonstrate that 18F-AH111585 can detect changes in tumor uptake following acute treatment with a VEGF signaling inhibitor (ZD4190). The results suggest that this imaging agent may be useful for monitoring changes in tumor vascularity.

No significant financial relationships to disclose.
BRCA1 breast cancer risk is modified by CYP19 polymorphisms in Ashkenazi Jews
Authors: Raskin L. , Lejbkowicz F. , Barnett-Griness O. , Reisfeld D. , Dishon S. , Almog R. , Rennert G.
Published: March 2020

10511

Background: The lack of full penetrance of mutations in the BRCA genes suggests the possible existence of other modifying genes and/or environmental factors. Exposure to sex hormones is an established major risk factor for breast cancer. The polymorphisms ( rs700518 (Val80), [TTTA]n) in CYP19, a gene encoding the estrogen synthesizing enzyme P450 aromatase, may be associated with risk of breast cancer in BRCA carriers and/or non-carriers. Methods: An analysis of 922 breast cancer cases and 901 healthy controls, including 408 BRCA carriers and 1,415 non-carriers was carried out. Cases and controls of Ashkenazi origin came from a population-based case-control study of breast cancer in Northern Israel, enriched with BRCA carriers (with and without cancer) from a clinical familial cancer service. DNA samples were genotyped for Ashkenazi BRCA1,2 mutations (185delAG, 5382insC, 6174delT) and CYP19 polymorphisms by allelic discrimination using 7900HT ABI sequence detection system. Statistical analyses were performed using SPSS, SAS, and R language. Results: The Val80 G/G genotype was associated with a significantly increased risk of breast cancer as compared to the A/A genotype in BRCA1 carriers (OR=2.2; 95%CI=1.04–4.53; p=0.039) but not in BRCA2 carriers (OR=0.45, 95%CI=0.17–1.16; p=0.098). A similar magnitude association, though not statistically significant, was found between the Val80 and ER-negative status of breast tumors. A reconstructed common haplotype composed of four haplotype-tagging SNPs in Haplotype Block 4, covering the CYP19 coding region, was also significantly associated with breast cancer risk in 210 carriers of BRCA1 (OR=3.4; 95%CI=1.5–7.8; p=0.004). No significant association between CYP19 polymorphisms and breast cancer risk was found in non-carriers. Conclusions: Our data suggest that the CYP19 Val80 polymorphism and a haplotype including this polymorphism are associated with increased breast cancer risk in BRCA1 carriers. As a higher number of repeats in intron 4 ([TTTA]n polymorphism) is found in complete linkage disequilibrium with the Val80 G allele and is associated with higher estrogen levels, this mechanism could explain the phenotypic uniqueness of the carriers.

No significant financial relationships to disclose.
Extracellular cleaved HER2 (p95) confers partial resistance to trastuzumab but not HSP90 inhibitors in models of HER2 amplified breast cancer
Authors: Chandarlapaty S. , Scaltriti M. , Baselga J. , Ye Q. , Solit D. , Norton L. , Rosen N.
Published: March 2020

10515

Background: Breast cancers containing an amplified copy of the HER2 receptor tyrosine kinase represent 20–30% of all cases and antibody directed therapy targeting the extracellular domain of HER2 with trastuzumab has proven broadly efficacious. However, resistance to trastuzumab is a common phenomenon. Recent work has identified a cleaved, 95kD version of HER2 that lacks the extracellular epitope in which the trastuzumab binding site is found. Presence of this so called “p95” has been correlated with a worse clinical prognosis. We hypothesized that p95 may enable tumor resistance to trastuzumab. Methods/Results: We established models of p95 expressing breast cancer by transfecting p95 into preexisting models of HER2 amplified breast cancer. We find that cells expressing p95 display increased resistance to the growth inhibitory effects of trastuzumab. The PI3K-AKT pathway that is downregulated by Trastuzumab is less affected in the p95 expressing cells. Furthermore, p95 demonstrates an association with HER3 that is unaffected by trastuzumab treatment. Next, we evaluated the efficacy of therapies targeted against the intracellular domain of HER2 such as the HSP90 inhibitor, 17-AAG. HER2 requires HSP90 for its conformational stability and inhibitors of HSP90 result in growth inhibition of HER2+ breast cancer. We find that p95 displays a similar requirement for HSP90 as inhibitors of HSP90 result in the degradation of p95. Moreover, cells overexpressing p95 are equally susceptible to the antitumor effects of HSP90 inhibitors as those without high levels of p95. Finally, we utilized an empirically derived, in vivo model of trastuzumab resistance that displays high level expression of p95. As with the transfected models, these tumors retain their sensitivity to HSP90 inhibitors as treatment of mice bearing tumors results in both degradation of HER2 and p95 as well as robust tumor growth inhibition. Conclusions: Given the presence of p95 in human breast tumor samples, the data suggest that p95 may play an important role in mediating clinical resistance to trastuzumab. They further suggest that such tumors may retain their sensitivity to targeted therapy against the intracellular portion of HER2 such as with lapatinib or 17-AAG.

No significant financial relationships to disclose.
Phase II trial of nab-paclitaxel (nanoparticle albumin-bound paclitaxel (ABX)) + capecitabine (XEL) in first-line treatment of metastatic breast cancer (MBC)
Authors: Somer B. G. , Schwartzberg L. S. , Arena F. , Epperson A. , Fu D. , Fortner B. V.
Published: March 2020

1053

Background: ABX and XEL both have substantial single agent activity in MBC. Taxane and anti-metabolite doublets improve response rate and TTP and longer survival. ABX administered weekly has an excellent safety and efficacy profile with maintenance of dose intensity. This study was designed to test the safety and efficacy of ABX + XEL given in a novel combination schedule. Methods: This phase II, multicenter open label study utilized ABX 125 mg/m2 IV on day 1, 8 and with no premeds and capecitabine 825 mg/m2 PO BID days 1–14 on a Q 3 week cycle. The primary endpoint is objective response rate, with evaluation performed after every 2 cycles. Entry criteria include measurable MBC by RECIST criteria, age >18, PS 0–2, no prior chemo for metastatic disease, > 6 months since adjuvant fluoropyrimidine and/or paclitaxel. Results: The full sample of 50 patients (pts) have been enrolled; data from 43 pts are available for analysis. Median age is 58 (range 23.7–90.6). 37% received prior adjuvant anthracycline and 33% prior adjuvant taxane. Median number of metastatic sites is 2 (range 1–7), with most common sites of disease liver, 53.5%; bone, 51.2%; and lung, 14%. 226 cycles of therapy have been delivered. 5 pts required a dose reduction in XEL (3 pts to 650 mg/m2; 2 to 550 mg/m2) and 4 pts had dose reduction in ABX to 100 mg/m2. XEL dose reductions occurred due to hand-foot syndrome (3), neutropenia (1), and fatigue (1). ABX dose reductions occurred due to mucositis, diarrhea, fatigue, and neuropathy (1 pt each). 10 pts had grade 3–4 non-hematologic AEs: 3 hand-foot syndrome, 4 fatigue, and 3 GI. Hematologic AEs included 4 with grade 3 and 1 with grade 4 neutropenia, and 2 with grade 4 febrile neutropenia. The most common AEs of any grade were GI (30), dermatological (23), fatigue (15), neuropathy (12), and hand-foot syndrome (11). The incidence of Grade 1–2 neuropathy was 25% (no grade 3–4). Of 38 pts available for analysis of response, the overall response rate is 47.5%: PR 39.5%, CR 8%. Total of 15 pts have stable disease, 20 pts have completed 6+ cycles.

No significant financial relationships to disclose.
Therapeutic starvation and autophagy in prostate cancer: A new paradigm
Authors: DiPaola R. S. , Dvorzhinski D. , May M. , Morton R. , Foran D. , Bray K. , Karp C. , White E.
Published: March 2020

10530

The metabolic fragility of cancer cells is magnified with the preferential utilization of glycolysis that metabolizes glucose inefficiently rather than oxidative phosphorylation (the “Warburg effect”) and from impaired mechanisms of survival. In fact, one pathway by which cells survive metabolic stress is thought to be autophagy, a catabolic process of organelle digestion, which creates ATP during periods on nutrient limitation. Remarkably, autophagy is often impaired in human prostate cancers, due to either activation of the PI-3 kinase/Akt/mTOR pathway, which normally inhibits autophagy, or through allelic loss of the essential autophagy gene beclin1. This suggests that prostate cancers may be susceptible to metabolic stress that can be exploited therapeutically. Using immortalized mouse epithelial prostate cells, as well as PC-3 and LNCaP cell lines, we demonstrated the cytotoxic effect of 2-deoxyglucose (2DG), as an inhibitor of glycolysis. We found that 2DG induced membrane translocation in cells characteristic of autophagy using a transfected pEGFP-LC3 autophagy marker construct. We then demonstrated that induction of autophagy was dependent on Beclin1 expression in these cell models using Beclin1 siRNA. Based on these data, we initiated a phase I/II clinical trial with 2DG in patients with advanced malignancies and prostate cancer, which is now ongoing. In an effort to develop markers of autophagy for assessment in a clinical trial, we stained a human prostate TMA (>35 patient cores) for Beclin1 by IHC. Beclin1 staining was increased in tumor tissue compared to normal tissue. Staining was imaged and digitized using a 40x volume scan on a high- throughput MedMicro whole slide scanner. The imaged specimens were stored in multi-tiled TIFF format on a redundant array of independent devices (RAID); staining will be analyzed using a color decomposition algorithm and compared to tumor characteristics as we have previously done (Foran DJ et al., IEEE Trans Inf Technol Biomed, 8:89–96, 2004). These data further support the rationale to inhibit metabolism in cancer and the potential importance of autophagy with metabolic approaches to therapy. Further imaging assessment and analysis of markers of autophagy such as Beclin1 are ongoing.

No significant financial relationships to disclose.
Circulating tumor cells (CTC): Assessment of treatment efficacy in metastatic breast cancer (MBC)
Authors: Liu M. C. , Shields P. , Isaacs C. , Warren R. , Cohen P. , Wilkinson M. , Zhang Y. , Shen R. , Luyegu K. , Gallagher A. L.
Published: March 2020

10535

Background: Preliminary data in MBC suggest that ≥5 CTC/7.5 mL blood is associated with worse progression free survival (PFS) and overall survival (OS), and that the persistence of ≥5 CTC/7.5 mL blood after the initiation of therapy predicts for treatment failure (NEJM 2004. 351:781.). We are conducting a prospective clinical research study to validate the prognostic and predictive significance of this serum biomarker in MBC. Methods: Serial CTC levels are obtained in patients starting a new systemic treatment regimen for progressive, radiographically measurable MBC. 10 mL samples of peripheral blood are collected before the start of treatment and then at 3–4 week intervals. All subjects are followed prospectively for PFS and OS, and they are offered the opportunity to continue CTC testing upon disease progression. CTC enumeration is performed on a 7.5 mL blood volume using the CellSearch technology (Veridex, LLC; Warren, NJ). Epithelial cells are immunomagnetically separated and fluorescently labeled, and nucleated (DAPI+) cells with the EpCAM+, cytokeratin 8/18/19+, and CD45- phenotype are counted as CTC. Clinical outcomes are based on radiographic studies and physical examination in accordance with RECIST criteria. Results: 46 of 100 subjects have been accrued, and 33 have completed at least one radiographic staging evaluation with a median follow up of 7 mos (range 2–18 mos). Treatment for the 33 evaluable patients includes chemotherapy (27%), endocrine therapy (46%), and combination therapy with a biologic agent (27%). At baseline, 85% (28/33) had at least 1 CTC/7.5 mL (range 1–78), and 27% (9/33) had ≥5 CTC/7.5 mL. Median PFS was 2.57 months and 6.77 months for subjects with ≥5 vs <5 CTC/7.5 mL at baseline, respectively (p=0.02). Conclusions: The current data validate the observation that baseline CTC levels correlate with PFS in patients with MBC and measurable disease. Patient accrual and data analysis are ongoing to confirm that persistent CTC levels ≥5/7.5 mL correlate with a lack of treatment efficacy and therefore are a reliable surrogate marker of disease responsiveness and PFS.

[Table: see text]
Characterization of the pathogenic mechanism of a novel BRCA2 variant in a Chinese family
Authors: Kwong A. , Wong L. P. , Chan K. , Ma E. , Khoo U. S. , Ford J. M.
Published: March 2020

10541

Background: Despite the identification of a large number of sequences in BRCA1/2 mutation analyses, many genetic alterations are classified as variants of unknown significance (VUS). Increasing data demonstrates ethnic variation of BRCA mutation. We report a novel BRCA2 VUS in a Chinese family with multiple breast cancers and characterized it as pathogenic by RNA analysis. Method: Peripheral blood was collected from the breast cancer proband and her family who were suspected to have a pathogenic mutation due the segregation of the disease phenotype and the young age of presentation of breast cancer. DNA and RNA was extracted from the blood. The entire coding regions and flanking introns of BRCA1/2 were screened for germline mutations using full gene sequencing and Multiplex Ligation -dependent Probe Amplification. Variant DNA alteration leading to an aberrant BRCA transcript was demonstrated by RT-PCR of the RNA and Polyacrylamide Gel Electrophoresis. Abnormal bands were cloned and direct sequencing conducted. Results: A germline mutation c.7806–9T>G was identified in the proband at the BRCA2 intron 16. This mutation was also found in 3 of her 4 sibling sisters with early breast cancer. The proband's mother harbored the same BRCA2 mutation in DNA extracted from archival gastric tumor tissues. Computational analyses showed that this mutation might give rise to a cryptic splice site for alternative RNA splicing. To confirm the pathogenicity, RT- PCR using specific primers flanking the cryptic splice site and sequencing was performed on RNA extracted from the proband's blood. Four different sizes of transcripts were found: wild type, r.7806_7874del , r.7806_7976del and r.7806–8_7806-lins. The latter 3 aberrant transcripts were not found in the 30 controls therefore polymorphism is unlikely. The r.7806–8_7806-lins transcript caused a frameshift which created a truncated protein; whereas the other two short transcripts produced shorter BRCA2 protein isoforms. Conclusion: We identified a novel BRCA2 VUS and classified it as pathogenic. Classification of VUS as neutral or pathogenic, particularly in ethnic groups where limited knowledge is known is a challenge. Research on the spectrum of mutations in diversed ethnic groups has important implications on management. [Genbank: DQ889340 ]

No significant financial relationships to disclose.
Impact of E27X cdkn2a mutation on p16 and p14arf expression in melanoma families and pancreatic cancer
Authors: Queirolo P. , Ghiorzo P. , Gargiulo S. , Gliori S. , Acquati M. , Boitano M. , Bodini G. , Segalla V. , Pugliese V. , Fornarini G. , Bianchi Scarrà G.
Published: March 2020

10543

Background: Mutations in the CDKN2A gene underlie melanoma susceptibility in as many as 50% of melanoma kindreds in selected populations, and several CDKN2A founder mutations have been described. Inherited mutations in CDKN2A have been found to be associated with other non-melanoma cancers including pancreatic cancer and neural system tumours. Here we report a novel germline mutation in exon 1 of the CDKN2A gene, E27X, which we first detected in melanoma patients living in or originally from a small geographic area bordering Liguria, in north-western Italy. A subset of melanoma kindreds positive for this mutation displayed pancreatic cancer and neuroblastoma. Methods: We investigated 70 pancreatic cancer patients from a case-control study living in or originally coming from a small geographic area bordering Liguria, in north-western Italy, for CDKN2A mutations and ARF. Results: 2 out of 70 patients displayed the E27X mutation and 1 of the 2 patients had a first degree relative affected by pancreatic cancer. Conclusions: E27X generates a premature stop codon, leading to dramatically reduced protein levels of p16 and leaving p14ARF unaltered. As pancreatic cancer and neural system tumours have been postulated to be preferentially associated with CDKN2A mutations located in exon 2 and/or affecting p14ARF alone, the position of E27X in exon 1a provides interesting insights towards clarifying the mechanisms by which the CDKN2A/ARF locus is involved in cancer predisposition. Its finding in pancreatic cancer patients confirms common susceptibility to melanoma and pancreatic cancer due to this CDKN2A exon 1 mutation.

No significant financial relationships to disclose.
Validation of the PREMM1,2 model for the prediction of MLH1/MSH2 germline mutation carriers in a population- based cohort of colorectal cancer (CRC) patients
Authors: Balmaña J. , Balaguer F. , Steyerberg E. W. , Stoffel E. M. , Castellví-Bel S. , Andreu M. , Castells A. , Syngal S.
Published: March 2020

10545

Background: PREMM1,2 is a predictive model for estimating the likelihood of finding a mutation in the MLH1 and MSH2 genes developed in a population at risk of Lynch syndrome (Balmaña et al. JAMA 2006). The EPICOLON cohort is a Spanish population-based series of 1222 patients with CRC (Piñol et al. JAMA 2005). Methods: All 1222 individuals underwent microsatellite instability (MSI) and immunohistochemistry (IHC) analysis for MLH1/MSH2. Patients whose tumours exhibited MSI or altered IHC underwent MLH1/MSH2 analysis (n=91). Sensitivity (Se), specificity, positive predictive value (PPV), and the areas under the receiver operating characteristics curves (AUC) for the PREMM1,2 model were calculated and compared with the Edinburgh model (Barnetson et al. NEJM 2006) and the Revised Bethesda guidelines (RBG). Results: Three-hundred and ninety six individuals (32%) had a PREMM1,2 score =5%, 287 (23%) fulfilled the RBG, and 75 (6%) had a Barnetson score =5%. A PREMM1,2 score =5% and the RBG identified all carriers with deleterious mutations (n=8, Se=100%), while a Barnetson score =5% missed 2 mutation carriers (Se= 75%). For PREMM1,2 and Barnetson scores =5% and fulfilment of the RBG, specificities were 68%, 94%, and 77%, respectively; and PPV were 2%, 8%, and 2.8%, respectively. The AUC was 0.93 (95% CI: 0.86–0.99) for the PREMM1,2 model and 0.86 (95% CI: 0.66–1.04) for the Barnetson model. The predictions of carrying a mutation stratified into five groups based on PREMM1,2 scores (<5%, 5–9%, 10–19%, 20–39%, =40%) correlated reasonably with the presence of mutations (0%, 1%, 1%, 13%, and 22%, respectively). Conclusions: In a population of CRC patients, the PREMM1,2 model identifies all mutation carriers of MSH2 and MLH1 using a cutoff of =5%. In addition, it provides quantification of risk that is useful to decide the strategy used for molecular evaluation and risk counselling of patients.

No significant financial relationships to disclose.