Endocrine Therapy Synergizes with SMAC Mimetics to Potentiate Antigen Presentation and Tumor Regression in Hormone Receptor-Positive Breast Cancer

Immunotherapies have yet to demonstrate significant efficacy in the treatment of hormone receptor-positive (HR+) breast cancer. Given that endocrine therapy (ET) is the primary approach for treating HR+ breast cancer, we investigated the effects of ET on the tumor immune microenvironment (TME) in HR+ breast cancer. Spatial proteomics of primary HR+ breast cancer samples obtained at baseline and after ET from patients enrolled in a neoadjuvant clinical trial (NCT02764541) indicated that ET upregulated β2-microglobulin and influenced the TME in a manner that promotes enhanced immunogenicity. To gain a deeper understanding of the underlying mechanisms, the intrinsic effects of ET on cancer cells were explored, which revealed that ET plays a crucial role in facilitating the chromatin binding of RelA, a key component of the NF-κB complex. Consequently, heightened NF-κB signaling enhanced the response to interferon-gamma, leading to the upregulation of β2-microglobulin and other antigen presentation-related genes. Further, modulation of NF-κB signaling using a SMAC mimetic in conjunction with ET augmented T-cell migration and enhanced MHC-I-specific T-cell-mediated cytotoxicity. Remarkably, the combination of ET and SMAC mimetics, which also blocks prosurvival effects of NF-κB signaling through the degradation of inhibitors of apoptosis proteins, elicited tumor regression through cell autonomous mechanisms, providing additional support for their combined use in HR+ breast cancer.

SIGNIFICANCE

Adding SMAC mimetics to endocrine therapy enhances tumor regression in a cell autonomous manner while increasing tumor immunogenicity, indicating that this combination could be an effective treatment for HR+ patients with breast cancer.

Definitive Radiotherapy for Oligometastatic and Oligoprogressive Thyroid Cancer

PURPOSE/OBJECTIVE(S)

Local consolidative radiotherapy (LCT) for oligometastatic disease is a promising paradigm improving outcomes for various malignancies but has been underexplored for metastatic thyroid cancer. We hypothesize that LCT to distant sites with definitive RT doses can yield favorable outcomes and defer systemic therapy escalation for these patients.

MATERIALS/METHODS

We reviewed 96 thyroid cancer patients who received 175 LCT courses from 2010-2022 to 228 metastatic sites, including: thorax (45%), bone (40%), brain (6%), head/neck (5%), and abdomen (3%). Common prescriptions were 50-55Gy/4-5fxs or 56-70Gy/8-10fxs for lung; 52.5-60Gy/15fxs for mediastinum; and 18-24Gy/1fx or 27-30Gy/3fxs for bone. RECIST v1.1 and CTCAE v5.0 were used to define progression and toxicities, respectively. Outcomes were evaluated via Kaplan-Meier and associations examined via Cox proportional hazards modeling.

RESULTS

Median age was 63 years (range: 26-92), with 62 oligometastatic cases (total 1-5 sites) and 34 oligoprogressive (with 1-5 growing sites). Primary disease was controlled in all patients, with 39% receiving post-op RT and 66% prior RAI. Histologies included papillary (40%), anaplastic (25%), follicular (12%), medullary (9%), Hurthle (7%), and poorly-differentiated (7%). Median time from initial diagnosis to LCT was 3 yrs (IQR 1-8), and median follow-up from 1st LCT was 21 mos (IQR 9-51). Patients received an average 2 LCT courses (range 1-8) treating 1-4 sites. Median survival (OS) from 1st LCT was 9 yrs (95% CI = 5-14). On multivariable analysis (MVA), worse OS was associated with anaplastic histology (HR 4.6, p<.01), but longer OS was associated with prior RAI (HR 0.33, p = .02) and oligometastatic disease (HR 0.3, p = .01). For anaplastic histology, median OS was 1.2 years vs. 9.3 years for non-anaplastic; 3-yr OS was 36% vs. 88% (log-rank, p<.01). Five-year OS for oligometastatic cases was 75% vs 53% for oligoprogressive (log-rank, p = .04). Median progression free survival (PFS) from 1st LCT was 15.5 mos (95% C I = 11-20). On MVA for all LCT courses, time to any progression (TTP) was negatively associated with anaplastic histology (HR 1.7, p = .02) and 2nd or higher LCT course (HR 1.45, p = .05), but favorably associated with thoracic site (HR 0.49, p<.01). Following later LCT courses, median TTP was 11 mos vs 17 mos for initial LCT course (log-rank, p = .03). After LCT to lung/chest, TTP was 18.6 mos vs 9.5 mos for non-thoracic sites (log-rank, p<.01). Only 6% of failures occurred at previously treated lesions. Most LCT courses (67%) were without ongoing chemotherapy, while 25% entailed continuing the same regimen and 9% had planned treatment post-RT. There were 2 Grade 3 toxicities (pneumonitis and esophagitis) and no Grade 4-5 events.

CONCLUSION

With high local control rates and minimal toxicity, LCT can be a feasible strategy to defer systemic therapy escalation for oligometastatic and oligoprogressive thyroid cancer.

Profile of and risk factors for early unplanned readmissions in patients with acute necrotizing pancreatitis

INTRODUCTION

Acute necrotizing pancreatitis (ANP) complicates up to 15% of acute pancreatitis cases. ANP has historically been associated with a significant risk for readmission, but there are currently no studies exploring factors that associate with risk for unplanned, early (<30-day) readmissions in this patient population.

METHODS

We performed a retrospective review of all consecutive patients presenting to hospitals in the Indiana University (IU) Health system with pancreatic necrosis between December 2016 and June 2020. Patients younger than 18 years of age, without confirmed pancreatic necrosis and those that suffered in-hospital mortality were excluded. Logistic regression was performed to identify potential predictors of early readmission in this group of patients.

RESULTS

One hundred and sixty-two patients met study criteria. 27.7% of the cohort was readmitted within 30-days of index discharge. The median time to readmission was 10 days (IQR 5-17 days). The most frequent reason for readmission was abdominal pain (75.6%), followed by nausea and vomiting in (35.6%). Discharge to home was associated with 93% lower odds of readmission. We found no additional clinical factors that predicted early readmission.

CONCLUSION

Patients with ANP have a significant risk for early (<30 days) readmission. Direct discharge to home, rather than short or long-term rehabilitation facilities, is associated with lower odds of early readmission. Analysis was otherwise negative for independent, clinical predictors of early unplanned readmissions in ANP.

Abstract GS3-07: GS3-07 Clonal evolution and mechanisms of acquired resistance to CDK4/6 inhibitors in ER-wild type and ER-mutant breast cancer

Background Despite the remarkable activity of CDK4/6 inhibitors (CDK4/6i) in the treatment of estrogen receptor positive (ER+) metastatic breast cancer (BC), most patients eventually develop resistance to these drugs. The ctDNA analysis of the PALOMA-3 trial showed that the estrogen receptor (ER) mutation Y537S is a potential mechanism of acquired resistance to the combination of endocrine therapy (ET) with CDK4/6i. To date, the role of the ER mutations in the clonal evolution and the mechanisms of acquired resistance to CDK4/6i is unknown. Moreover, it is not known if the development of resistance to CDK4/6i in the presence or absence of ER mutations is due to the expansion of pre-existing resistant clones or to the de novo acquisition of resistance mechanisms. Methods To explore the clonal evolution and the mechanisms of resistance to CDK4/6i in ER-wild type (ER-WT) and ER-mutant (ER-Mut) BC, we transduced doxycycline (DOX)-inducible Y537S ER-Mut MCF7 cells with the ClonTracer library, a high-complexity DNA barcode library, and cultured the barcoded cells without DOX (MCF7), or with DOX to induce the expression of the Y537S ER mutation (MCF7-YS). To develop Palbociclib (Palbo)-resistant (PDR) and Abemaciclib (Abema)-resistant (ABR) cell models, the barcoded MCF7 and MCF7-YS cells were passaged in culture with increasing concentrations of Palbo and Abema until the acquisition of resistance. The clonal dynamics and the molecular characteristics of the PDR and ABR models were investigated by barcode sequencing, whole-exome sequencing (WES), bulk and single cell RNA sequencing (RNAseq) and protein analyses. Finally, using an ER-Mut barcoded mice model, we compared the in vitro clonal evolution of ER-Mut CDK4/6i-resistant cells with the in vivo clonal evolution of ER-Mut metastases. Results The analysis of the barcodes revealed that during the acquisition of resistance to either Palbo or Abema there is a strong clonal selection of pre-existing resistant clones. The PDR clones were different in the presence of the Y537S mutation versus WT-ER. In contrast, the clones enriched in the ABR cells were comparable between WT and mutant ER. Furthermore, the ER mutations led to decreased diversity of the enriched clones in the PDR but not in the ABR cells. Interestingly, the barcodes enriched in the PDR and ABR models did not overlap. Unsupervised analyses showed that the samples clustering based on the barcodes fractions and the mutations were similar, suggesting that the clonal selection was driven by cellular populations with specific mutational landscapes. All the ER-WT and ER-Mut resistant models had different transcriptional profiles and by single-cell RNAseq showed various degrees of intra-sample heterogeneity. At the protein level, the PDR and the ABR cells displayed downregulation of ER, Rb and p27 and upregulation of p21. In the ER-Mut conditions Cyclin D1 was upregulated in the PDR cells, while Cyclin E was upregulated in the ABR cells. Finally, the barcode sequencing of the mice metastases revealed that the clonal selection in ER-Mut metastases and in ER-Mut CDK4/6i-resistant cells is different. Conclusion Our study suggests that the development of resistance to CDK4/6i is due to the selection of pre-existing resistant clones. We also demonstrate that the expression of the Y537S ER mutation impacts the clonal evolution and the mechanisms of acquired resistance to Palbo but not to Abema. Finally, we show that the clonal evolution and mechanisms are disparate in Palbo and Abema resistance. These results support the addition of a third drug to CDK4/6i and ET, early in treatment, to delay the selection of pre-existing resistant clones and prolong the response to treatment and highlight differences between Palbo and Abema.

Citation Format: Cristina Guarducci, Simona Cristea, Avery Feit, Sergey Naumenko, Agostina Nardone, Wen Ma, Douglas Russo, Gabriella Cohen Feit, Ariel Feiglin, Francisco Hermida-Prado, Shira Sherman, Myles Brown, Franziska Michor, Rinath Jeselsohn. GS3-07 Clonal evolution and mechanisms of acquired resistance to CDK4/6 inhibitors in ER-wild type and ER-mutant breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS3-07.

Complexation reduces nickel toxicity to purple sea urchin embryos (Strongylocentrotus purpuratus), a test of biotic ligand principles in seawater

The potential for Ni toxicity in seawater is of concern because of mining and processing activities in coastal regions. Determining Ni speciation is vital to understanding and predicting Ni toxicity and for bioavailability-based nickel risk assessment. The goal of this study was to characterize the complexation of Ni in relation to toxicity using embryological development of purple sea urchin (S. purpuratus). It was predicted that free ion [Ni2+] would be a better predictor of toxicity than total dissolved Ni concentrations (NiD). Synthetic ligands with known logKf values (Ethylenediaminetetraacetic acid (EDTA), Nitrilotriacetic acid (NTA), tryptophan (TRP), glutamic acid (GA), histidine (HD), and citric acid (CA)) were used to test the assumptions of the biotic ligand model (BLM) for Ni in seawater. [NiD] was measured by graphite furnace atomic absorption spectroscopy (GFAAS) and Ni2+ was first quantified using the ion-exchange technique (IET) and then concentrations were measured by GFAAS; [Ni2+] was also estimated using aquatic geochemistry modelling software (Visual Minteq). The mean EC50 values for [NiD] in unmodified artificial seawater control was 3.6 µM (95% CI 3.0-4.5) [211 µg/L 95% CI 176-264] and the addition of ligands provided protection, up to 6.5-fold higher [NiD] EC50 for EDTA. Compared to the control, measured EC50 values based on total dissolved nickel were higher in the presence of ligands. As predicted by BLM theory, [Ni2+] was a better predictor of Ni toxicity with 17% variability in EDTA and CA media while there was 72% variability in the prediction of Ni toxicity with total dissolved Ni. The results of this research provide support for the application of BLM- based prediction models for estimating Ni impacts in seawater.

Should we be imaging lymph nodes at initial diagnosis of early-stage mycosis fungoides? Results from the PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) international study

BACKGROUND

Early-stage mycosis fungoides (MF) includes involvement of dermatopathic lymph nodes (LNs) or early lymphomatous LNs. There is a lack of unanimity among current guidelines regarding the indications for initial staging imaging in early-stage presentation of MF in the absence of enlarged palpable LNs.

OBJECTIVES

To investigate how often imaging is performed in patients with early-stage presentation of MF, to assess the yield of LN imaging, and to determine what disease characteristics promoted imaging.

METHODS

A review of clinicopathologically confirmed newly diagnosed patients with cutaneous patch/plaque (T1/T2) MF from PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) data.

RESULTS

PROCLIPI enrolled 375 patients with stage T1/T2 MF: 304 with classical MF and 71 with folliculotropic MF. Imaging was performed in 169 patients (45%): 83 with computed tomography, 18 with positron emission tomography-computed tomography and 68 with ultrasound. Only nine of these (5%) had palpable enlarged (≥ 15 mm) LNs, with an over-representation of plaques, irrespectively of the 10% body surface area cutoff that distinguishes T1 from T2. Folliculotropic MF was not more frequently imaged than classical MF. Radiologically enlarged LNs (≥ 15 mm) were detected in 30 patients (18%); only seven had clinical lymphadenopathy. On multivariate analysis, plaque presentation was the sole parameter significantly associated with radiologically enlarged LNs. Imaging of only clinically enlarged LNs upstaged 4% of patients (seven of 169) to at least IIA, whereas nonselective imaging upstaged another 14% (24 of 169). LN biopsy, performed in eight of 30 patients, identified N3 (extensive lymphomatous involvement) in two and N1 (dermatopathic changes) in six.

CONCLUSIONS

Physical examination was a poor determinant of LN enlargement or involvement. Presence of plaques was associated with a significant increase in identification of enlarged or involved LNs in patients with early-stage presentation of MF, which may be important when deciding who to image. Imaging increases the detection rate of stage IIA MF, and identifies rare cases of extensive lymphomatous nodes, upstaging them to advanced-stage IVA2.

Cardiotoxicity manifestations in metastatic breast cancer patients treated with trastuzumab as first line

e13011

Background: Trastuzumab is a monoclonal antibody that targets the human epidermal growth factor receptor-2 (HER2). Its use may result in cardiotoxicity. There are no formal guidelines for left ventricular ejection fraction (LVEF) monitoring in patients with metastatic disease treated with trastuzumab. Our local guideline include an echocardiogram every 3 months for these patients. Methods: We collected data from electronic records and hard copy files of patients treated with Trastuzumab as first line, between the years 2011-2014. Results: One hundred patients met the inclusion criteria. Median treatment duration of all patients was 30 months, with an average of 12 echocardiogram follow-ups per patient. Ninety-nine patients (99%) received additional chemotherapy. Thirty patients (30%) also received Pertuzumab. Ten (10%) of the eligible 100 patients showed significant decline in EF (≥10%) to a final LVEF of < 50%. The median follow-up duration of these patients was 52 months. Median EF at the beginning of treatment was 61.5% in all patients. Cardiotoxicity occurred at an average of 23 months [median 18 months] after beginning of Trastuzumab treatment (range; 3-54 months), with an average EF decline of 14% (range; 10-18%). Three patients (30%) required treatment change due to the decline in EF. Temporary cessation of treatment was necessary in 4 (40%) of the patients for a period of time between 4 weeks to 8 months. The remaining 3 patients (30%), although developing significant decline in EF, did not require treatment cessation or change. None of the 10 patients presented any other clinical sign of cardiotoxicity. In the group with cardiac events, there were no previous reports of congestive heart failure (CHF), ischemic heart failure (IHF), myocardial infraction (MI) or diabetes. Only one patient was a smoker and another received hormone replacement therapy. The average age of this group at the time of diagnosis of metastatic disease was younger (50.6 vs. 55.8, P-value 0.5). Conclusions: Monitoring heart function by trimonthly echocardiogram does not seem to be the optimal monitoring modality in metastatic breast cancer patients who receive a trastuzumab-containing regimen as first line. This study results suggest that less frequent monitoring may be sufficient, thus diminishing patients' inconvenience and allowing better allocation of health care resources.

Efficacy of immune check-point inhibitors (ICPi) in large cell neuroendocrine tumors of lung (LCNEC)

OBJECTIVES

Little is known regarding the ICPi efficacy in LCNEC. We explored the efficacy and safety of ICPi in LCNEC and assessed its impact on OS.

MATERIALS AND METHODS

Thirty-seven consecutive patients with advanced LCNEC were selected from the Davidoff Cancer Center database. These were divided into groups A1 (patients treated with ICPi, n-23) and A2 (patients not treated with ICPi, n-14). Additionally, group A1* was introduced (patients treated with ICPi as a monotherapy, n-21). Another cohort of advanced non-LCNEC lung cancer patients treated with nivolumab at five Israeli cancer centers was chosen as a comparator (group B, n-270). ORR, PFS with ICPi in group A1* were assessed (RECIST 1.1), OS with ICPi was compared between groups A1* and B. OS since advanced disease diagnosis (OSDx) was compared between groups A1 and A2.

RESULTS

In group A1*, ORR and median PFS with ICPi were 33 %, and 4.2 months (95 % CI, 2.4-8.1), respectively. With median follow-up since start of ICPi of 6.2 months [IQR 2.2-12.1] and 4.9 months [IQR 2.3-8.9] in groups A1* and B, respectively, 52 % and 64 % of patients died in groups A1* and B, respectively. Median OS with ICPi comprised 11.8 months (95 % CI, 3.7-NR) and 6.9 months (95 % CI, 5.5-8.1) in groups A1* and B, respectively (p-0.23). Median OSDx was 14.5 months (95 % CI, 10.1-38.9) and 10.3 months (95 % CI, 2.6-NR), in groups A1 and A2, respectively (p-0.54).

CONCLUSION

In advanced LCNEC, ICPi outcomes are comparable to the outcomes observed in advanced NSCLC. Future research is needed to clarify the impact of ICPi on OS, and to correlate its benefit with tumor mutational landscape.

Grover disease and bullous pemphigoid: a clinicopathological study of six cases

Grover disease (GD) is an idiopathic dermatosis that typically manifests as itchy papules over the trunk in middle-aged men. Bullous pemphigoid (BP) is an autoimmune bullous disease that affects older people. Not only are the two diseases easily distinguishable on clinical grounds, they are also characterized by differences in histopathology, pathogenesis and response to treatment Thus, the co-occurrence of these two conditions in the same patient is usually considered coincidental. In this report, we present a multicentre retrospective analysis of six patients who developed both GD and BP over a short period of time, and in all cases but one, GD preceded BP. We discuss the clinical and histopathological features of these patients, and the suggested mechanisms of the diseases. We conclude that GD might predispose to the development of BP.

Relating the Electrical Resistance of Fresh Concrete to Mixture Proportions

Characterization of fresh concrete is critical for assuring the quality of our nation's constructed infrastructure. While fresh concrete arriving at a job site in a ready-mixed concrete truck is typically characterized by measuring temperature, slump, unit weight, and air content, here the measurement of the electrical resistance of a freshly cast cylinder of concrete is investigated as a means of assessing mixture proportions, specifically cement and water contents. Both cement and water contents influence the measured electrical resistance of a sample of fresh concrete: the cement by producing ions (chiefly K⁺, Na⁺, and OH^-) that are the main source of electrical conduction; and the water by providing the main conductive pathways through which the current travels. Relating the measured electrical resistance to attributes of the mixture proportions, such as water-cement ratio by mass (w/c), is explored for a set of eleven different concrete mixtures prepared in the laboratory. In these mixtures, w/c, paste content, air content, fly ash content, high range water reducer dosage, and cement alkali content are all varied. Additionally, concrete electrical resistance data is supplemented by measuring the resistivity of its component pore solution obtained from 5 laboratory-prepared cement pastes with the same proportions as their corresponding concrete mixtures. Only measuring the concrete electrical resistance can provide a prediction of the mixture's paste content or the product w*c; conversely, when pore solution resistivity is also available, w/c and water content of the concrete mixture can be reasonably assessed.

Overall survival analysis of EXAM, a phase III trial of cabozantinib in patients with radiographically progressive medullary thyroid carcinoma

BACKGROUND

Primary analysis of the double-blind, phase III Efficacy of XL184 (Cabozantinib) in Advanced Medullary Thyroid Cancer (EXAM) trial demonstrated significant improvement in progression-free survival with cabozantinib versus placebo in patients with progressive medullary thyroid cancer (MTC). Final analysis of overall survival (OS), a key secondary endpoint, was carried out after long-term follow-up.

PATIENTS AND METHODS

EXAM compared cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomized (2:1) to cabozantinib (140 mg/day) or placebo. Final OS and updated safety data are reported.

RESULTS

Minimum follow-up was 42 months. Kaplan-Meier analysis showed a 5.5-month increase in median OS with cabozantinib versus placebo (26.6 versus 21.1 months) although the difference did not reach statistical significance [stratified hazard ratio (HR), 0.85; 95% confidence interval (CI), 0.64-1.12; P = 0.24]. In an exploratory assessment of OS, progression-free survival, and objective response rate, cabozantinib appeared to have a larger treatment effect in patients with RET M918T mutation-positive tumors compared with patients not harboring this mutation. For patients with RET M918T-positive disease, median OS was 44.3 months for cabozantinib versus 18.9 months for placebo [HR, 0.60; 95% CI, 0.38-0.94; P = 0.03 (not adjusted for multiple subgroup analyses)], with corresponding values of 20.2 versus 21.5 months (HR, 1.12; 95% CI, 0.70-1.82; P = 0.63) in the RET M918T-negative subgroup. Median treatment duration was 10.8 months with cabozantinib and 3.4 months with placebo. The safety profile for cabozantinib remained consistent with that of the primary analysis.

CONCLUSION

The secondary end point was not met in this final OS analysis from the trial of cabozantinib in patients with metastatic, radiographically progressive MTC. A statistically nonsignificant increase in OS was observed for cabozantinib compared with placebo. Exploratory analyses suggest that patients with RET M918T-positive tumors may experience a greater treatment benefit with cabozantinib.

TRIAL REGISTRATION NUMBER

NCT00704730.

Oncogenic role of microRNA-155 in mycosis fungoides: an in vitro and xenograft mouse model study

BACKGROUND

MicroRNA (miR)-155 contributes to the proliferation of mycosis fungoides (MF) in vitro and is upregulated in tumours of MF compared with early MF lesions.

OBJECTIVES

To investigate the contribution of miR-155 to the cancerous phenotype and drug resistance of MF/Sézary cell lines.

METHODS

miR-155 was inhibited in MF cell lines (MyLa and MJ) by transduction of miRZip anti-miR-155, and overexpressed in Hut78 cells by transduction of miRVec-miR-155; empty plasmids served as controls. Cells were analysed for response to inducers of apoptosis and cell-cycle arrest, using fluorescence-activated cell sorting. Transduced MyLa cells were subcutaneously injected into severe combined immunodeficient mice, and tumours were analysed immunohistochemically and for final size.

RESULT

MyLa and MJ cells expressed a high level of miR-155; Hut78 cells expressed a low level. MF cell lines stably expressing miR-155 inhibitor showed increased G2/M arrest in response to N-p-tolyl-2-(3,4,5-trimethoxyphenyl quinazolin-4-amine) (SL111), an inducer of cell-cycle arrest, followed by increased apoptosis. Additionally, they showed increased apoptosis in response to suberoylanilide hydroxamic acid (SAHA). Tumours formed in mice from injected anti-miR-155-expressing MyLa cells had a significantly lower volume and higher occurrence of apoptosis than controls. Stable overexpression of miR-155 in Hut78 cells had no effect.

CONCLUSIONS

Oncogenic miR-155 appears to contribute to the cancerous phenotype of MyLa and MJ cells, but not of Hut78 cells, by interrupting activation of the G2/M checkpoint in response to SL111, and decreasing apoptosis in response to SL111 and SAHA, thereby facilitating tumour growth. These findings have implications for the potential development of novel therapeutic modalities for MF incorporating miR-155 inhibitors.

Tumor marker and measurement fluctuations may not reflect treatment efficacy in patients with medullary thyroid carcinoma on long-term RET inhibitor therapy

BACKGROUND

RET kinase inhibitors have significant activity in patients with medullary thyroid carcinoma (MTC).

PATIENTS AND METHODS

We retrospectively reviewed the electronic medical record for patterns of calcitonin, carcinoembryonic antigen (CEA) and tumor measurement responses in consecutive patients with MTC who received treatment with a RET inhibitor for at least 6 months.

RESULTS

Twenty-six patients who received RET kinase inhibitors for at least 6 months were included. All patients experienced an initial decline in calcitonin; 20 (77%) demonstrated later fluctuations in calcitonin, which spiked above baseline levels in 9 individuals (35%). Twenty of the 22 patients (91%) with elevated CEA experienced a decline with treatment, with 11 individuals (50%) later demonstrating transient fluctuations in CEA, including spikes above baseline in 7 patients (32%). Ten of the 26 patients (38%) also demonstrated short-lived fluctuations in RECIST measurements, including changes of over 20% from nadir values. Vacillations in calcitonin, CEA and measurements often occurred repeatedly in individual patients and did not regularly correlate with each other.

CONCLUSIONS

Repeated transient fluctuations in tumor markers and measurements are a characteristic of patients with MTC receiving treatment with RET inhibitors, and such short-term vacillations may not reflect responsiveness over the long term.

CLINICAL TRIALS INCLUDED

NCT00215605; NCT00244972; NCT00121680; NCT00495872.

Accuracy of magnetic resonance cholangiopancreatography in the diagnosis of pancreas divisum

BACKGROUND

Patients with pancreas divisum may develop pancreatitis. Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for diagnosing pancreas divisum. Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive test reported to be highly accurate in diagnosing pancreas divisum.

AIM

To evaluate the diagnostic accuracy of MRCP in detecting pancreas divisum at our institution.

METHODS

We reviewed patients who underwent both ERCP and MRCP. Patients who had diagnostic endoscopic pancreatograms (ERP) after MRCP comprise the study population. Secretin was given in 113/146 patients (S-MRCP). The remaining 33/146 patients had MRCP without secretin. In 7/33 patients who underwent MRCP without secretin (21.2%), the studies were non-diagnostic and, therefore, this group was not further analyzed and the study focused on the S-MRCP group only.

RESULTS

ERP identified pancreas divisum in 19/113 (16.8%) patients. S-MRCP identified 14/19 pancreas divisum and was false-positive in three cases (sensitivity 73.3%, specificity 96.8%, positive predictive value 82.4%, negative predictive value 94.8%). Of the eight patients with inaccurate S-MRCP, 5 (63%) had changes of chronic pancreatitis by ERP. This differs from the frequency of chronic pancreatitis by ERP in 24/105 (23%) patients with accurate MRCP findings. The ERCP findings of chronic pancreatitis were more frequent among incorrect S-MRCP interpretations than among correct interpretations (odds ratio [OR] 5.5 [95% confidence interval (CI) 1.3-25.3]). MRCP without secretin is non-diagnostic for pancreas divisum in a significant proportion of patients. S-MRCP had a satisfactory specificity for detecting pancreas divisum. However, the sensitivity of S-MRCP for the diagnosis of pancreas divisum was modest at 73.3%. This is low compared to previous smaller studies, which reported a sensitivity of MRCP of up to 100%.

Adjusted indirect comparison of everolimus and sorafenib in sunitinib-refractory mRCC patients using a robust matching technique

378

Background: Vascular endothelial growth factor receptor–tyrosine kinase inhibitors (VEGFr-TKIs) sunitinib (SU) and sorafenib (SO) are approved for first- and second-line (after cytokines) use in metastatic renal cell carcinoma (mRCC). Because most patients progress after first-line VEGFr-TKI, the need for an effective second-line treatment is compelling. Although SO is frequently considered after SU failure, no randomized controlled trials have established clinical benefit in this scenario. Results from the RECORD-1 phase III trial suggest that second-line everolimus (EVE) therapy leads to improved overall survival (OS) vs. placebo. No trial data exist comparing treatment outcomes for EVE vs SO in the second-line setting. Thus, the current analysis provides a robust estimate from an indirect comparison examining the OS benefit of EVE and SO as second-line treatment options after SU failure.

Methods: The single-arm SO study was selected as a basis by which to match an EVE SU-refractory subpopulation of the RECORD-1 trial. Patients were limited to those with clear cell histology. An adjusted matching approach was taken in which 1,000 repeated random samples matched to the SO population on risk score distribution were produced. These data were used to generate a distribution of survival outcomes and infer a 95% CI around the mean of all sampled median OS estimates.

Results: After adjusted matching, the estimated median OS benefit, based on SO patients with clear cell histology (n = 45) and 1000 random samples of n = 41 from the 127 SU-refractory EVE patients, was 82 weeks (95% CI: 78, 86) and 32 weeks (95% CI: 22, 64) for EVE and SO, respectively.

Conclusions: These indirect comparison results suggest that SU-refractory mRCC patients treated with EVE may experience significantly improved OS outcomes compared with patients treated with SO.

[Table: see text]

TFT Performance - Material Quality Correlation for a-Si:H Deposited at high Rates

We evaluated the characteristics of a-Si:H/a-SiNx:H thin film transistors (TFTs), and of separately deposited a-Si:H films, as functions of the a-Si:H deposition power in a high-rate, large-area, 40 MHz PE-CVD system. TFT performance and a-Si:H film properties improve with decreasing power density and deposition rate. However, low defect density a-Si:H material was deposited at rates as high as 1500 Å/min. TFTs with gate nitride deposited at 1000 A/min show excellent I-V characteristics when the a-Si:H deposition power is low enough. The TFT electron mobility in the linear regime correlates well with the Urbach energy of the a-Si:H films, suggesting that the quality of the a-Si: H controls the performance of our TFTs.

Use and perceived effectiveness of non-analgesic medical therapies for chronic pancreatitis in the United States

BACKGROUND

Effectiveness of medical therapies in chronic pancreatitis has been described in small studies of selected patients.

AIM

To describe frequency and perceived effectiveness of non-analgesic medical therapies in chronic pancreatitis patients evaluated at US referral centres.

METHODS

Using data on 516 chronic pancreatitis patients enrolled prospectively in the NAPS2 Study, we evaluated how often medical therapies [pancreatic enzyme replacement therapy (PERT), vitamins/antioxidants (AO), octreotide, coeliac plexus block (CPB)] were utilized and considered useful by physicians.

RESULTS

Oral PERT was commonly used (70%), more frequently in the presence of exocrine insufficiency (EI) (88% vs. 61%, P < 0.001) and pain (74% vs. 59%, P < 0.002). On multivariable analyses, predictors of PERT usage were EI (OR 5.14, 95% CI 2.87-9.18), constant (OR 3.42, 95% CI 1.93-6.04) or intermittent pain (OR 1.98, 95% CI 1.14-3.45). Efficacy of PERT was predicted only by EI (OR 2.16, 95% CI 1.36-3.42). AO were tried less often (14%) and were more effective in idiopathic and obstructive vs. alcoholic chronic pancreatitis (25% vs. 4%, P = 0.03). Other therapies were infrequently used (CPB - 5%, octreotide - 7%) with efficacy generally <50%.

CONCLUSIONS

Pancreatic enzyme replacement therapy is commonly utilized, but is considered useful in only subsets of chronic pancreatitis patients. Other medical therapies are used infrequently and have limited efficacy.

A prospective study comparing rapid assessment of smears and ThinPrep for endoscopic ultrasound-guided fine-needle aspirates

BACKGROUND AND STUDY AIMS

ThinPrep is often used for endoscopic ultrasound fine-needle aspiration (EUS-FNA) samples but the sensitivity of this method is unknown. The objective of the study was to compare sensitivity and accuracy of ThinPrep versus the smear method in pancreas and lymph node samples obtained by EUS-FNA.

PATIENTS AND METHODS

Patients with suspected malignancy in the pancreas or lymph node underwent EUS-FNA. On-site rapid assessment of all aspirates using the smear method was performed. After rapid assessment, three additional passes from each site were submitted into ThinPrep liquid medium. Cytopathologists interpreting the smear method and ThinPrep slides were blinded to each other. The gold standard was final cytology or pathology results.

RESULTS

A total of 130 patients (36 % women, mean age 63 years) underwent EUS-FNA of 139 sites (50 pancreas, 89 lymph node). Malignancy was confirmed in 47 pancreas samples (94 %) and 48 lymph node samples (54 %). Mean +/- SD number of passes made for the smear method was 2.6 +/- 1.3. For pancreatic cancer, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the ThinPrep versus the smear method were: 62 % versus 98 %, 100 % versus 100 %, 100 % versus 100 %, 14 % versus 75 %, and 64 % versus 98 %, respectively. For lymph nodes the values were 67 % versus 92 %, 100 % versus 98 %, 100 % versus 98 %, 72 % versus 72 %, and 82 % versus 94 %, respectively.

CONCLUSIONS

The smear method is more sensitive and accurate than ThinPrep in detecting malignancy from EUS-FNA samples of the pancreas and lymph nodes. Smear method with on-site rapid assessment should be favored over ThinPrep in suspected malignancy.

Frequency of sphincter of Oddi dysfunction in patients with previously normal sphincter of Oddi manometry studies

BACKGROUND AND STUDY AIMS

Sphincter of Oddi manometry (SOM), performed at endoscopic retrograde cholangiopancreatography (ERCP), is the gold standard for diagnosing sphincter of Oddi dysfunction (SOD). The question remains as to whether the short-term manometric recordings reflect the 24-hour pathophysiology of the sphincter. The aim of this study was to determine the frequency of SOD in persistently symptomatic patients with previously normal SOM studies.

PATIENTS AND METHODS

All patients who underwent ERCP for suspected SOD over a 13-year period (1994 - 2007) were considered for inclusion in the study. Patients with an intact papilla and a previously normal SOM who had a repeat ERCP for persistent symptoms formed the study group. SOM was performed in conventional retrograde fashion.

RESULTS

In all, 5352 patients without prior papillary intervention underwent SOM during the study period. A total of 1037 patients had normal SOM, and of these, 30 patients (27 female, mean age 40.1 years) underwent repeat ERCP for persistent symptoms. The median duration between the two ERCPs was 493.5 days (range 52-3538 days). In these 30 patients, SOD classification prior to the initial ERCP was: type I in one patient (not treated in 1994), type II in 17 patients, and type III in 12 patients. Of the 30 patients, 12 (40%) had normal SOM at repeat ERCP; SOD was diagnosed in 18/30 (60%) patients.

CONCLUSIONS

A single SOM study may not represent the day-to-day physiology of the sphincter of Oddi; sphincter pathology may progress over time. One normal exam may not rule out SOD. A repeat ERCP with manometry may be warranted in a subset of patients with persistent debilitating symptoms and a high index of suspicion for SOD. Outcome data are needed to determine whether this approach justifies the potential risks of ERCP.

The influence of variable-stiffness guide wires on basal biliary sphincter of Oddi pressure measured at endoscopic retrograde cholangiopancreatography

BACKGROUND

Guide wires are commonly utilized to facilitate endoscopic procedures. However, their use may adversely influence the results of sphincter of Oddi manometry, thereby leading to erroneous diagnosis and therapy. The aim of this study was to evaluate the effect of guide wires on the basal pressure of the biliary sphincter of Oddi.

METHODS

Forty-five consecutive patients with suspected sphincter of Oddi dysfunction were enrolled. Biliary sphincter of Oddi manometry was performed with and without a guide wire in the conventional retrograde fashion with a low-compliance infusion pump system, an aspirating catheter, and slow station pull-throughs. Three types of guide wires were studied: the Roadrunner (18 patients), the Glidewire (17 patients), and the standard Teflon guide wire (10 patients). The stiffness of the guide wires was tested and reported in Taber Stiffness Units (TSU; higher values represent greater stiffness).

RESULTS

Biliary sphincter of Oddi manometry performed with a guide wire revealed higher basal pressure than the same measurement performed without a guide wire (52 +/- 33.4 mmHg vs. 34.4 +/- 20.5 mmHg; P = 0.001). Basal pressure changes induced by guide-wire use were highest in the Roadrunner group (32.9 +/- 33.9 mmHg), lowest in the standard Teflon group (11.6 +/- 8 mmHg; Roadrunner vs. standard Teflon: P = 0.02), and intermediate in the Glidewire group (17.1 +/- 22.1 mmHg). The use of a guide wire resulted in crossover from normal to abnormal basal pressure in 11 cases (Roadrunner, 7; Glidewire, 4) and from abnormal to normal in 2 (Roadrunner, 1; Glidewire, 1). Concordance between recordings obtained with and without guide wire was seen in 32 patients (71 %). Guide-wire stiffness was: Roadrunner: 0.74 TSU; Glidewire: 0.153 TSU; standard Teflon guide wire: 0.077 TSU.

CONCLUSION

The use of guide wires frequently alters the basal biliary sphincter pressure, leading to incorrect diagnoses in approximately 40 % of cases. The basal pressure alterations depend on the stiffness of the guide wire used. Hence, the use of guide wires during sphincter of Oddi manometry is strongly discouraged.

Endoscopic ultrasound-guided fine-needle aspiration with or without flow cytometry for the diagnosis of primary pancreatic lymphoma - a case series

The role of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with flow cytometry for the diagnosis of primary pancreatic lymphoma (PPL) has not been previously described. Our aims were to describe the EUS features of PPL and the role of EUS-FNA with and without flow cytometry in the diagnosis of 16 patients. When EUS-FNA with flow cytometry was compared with EUS-FNA without flow cytometry, the sensitivities for diagnosing non-Hodgkin's lymphoma were 84.6 % versus 30.8 %, respectively ( P = 0.01). EUS-FNA with flow cytometry is a valuable tool to diagnose PPL. Flow cytometry analysis complements traditional assessment by standard cytology.

EUS and clinical characteristics of cystic pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) may rarely appear as cystic or mixed solid-cystic masses. The endoscopic ultrasound (EUS) morphology and cyst fluid characteristics of these tumors are not well clarified. We retrospectively identified nine adult patients with nine single cystic pancreatic neuroendocrine tumors (CNETs). These nine included 0.67 % of the 1344 patients with pancreatic cystic lesions and 9.5 % of the 95 confirmed PNETs evaluated over the 12-year study period. At presentation, four patients were asymptomatic and five had known acute pancreatitis (n = 2), MEN-1 syndrome with hypoglycemia (n = 1), and abdominal pain (n = 2). Median maximal tumor diameter was 26 mm (range 20 - 64 mm). EUS morphology was mixed solid and cystic (n = 4) or cystic alone (n = 5). Cytology from EUS-fine-needle aspiration (FNA) (median 2 passes; range 1 - 6) demonstrated a PNET, and immunocytochemistry was confirmatory in all patients. Cyst fluid carcinoembryonic antigen (CEA) (n = 4) and amylase (n = 5) ranged from 0.1 to 1.8 ng/ml (normal 0 - 2.5 ng/ml) and 72 to 1838 U/L (normal 25 - 161 U/L), respectively. Six patients underwent surgery, and the preoperative diagnosis was confirmed in all.