Impact of encorafenib on survival of patients with BRAFV600E-mutant metastatic colorectal cancer in a real-world setting

PURPOSE

Patients with BRAFV600E-mutant metastatic colorectal cancer (mCRC) have a dismal prognosis. The best strategies in these patients remain elusive. Against this background, we report the clinical course of patients with BRAFV600E-mutant mCRC to retrieve the best treatment strategy.

PATIENTS AND METHODS

Clinico-pathological data were extracted from the electronic health records. Kaplan-Meier method was used to estimate overall (OS) and progression-free survival (PFS). Objective response rate (ORR) was assessed according to RECIST 1.1.

RESULTS

In total, 51 patients were enrolled. FOLFOXIRI was administered to 12 patients; 29 patients received FOLFOX or FOLFIRI as first-line treatment. Median OS was 17.6 months. Median PFS with FOLFOXIRI (13.0 months) was significantly prolonged (HR 0.325) as compared to FOLFOX/FOLFIRI (4.3 months). However, this failed to translate into an OS benefit (p = 0.433). Interestingly, addition of a monoclonal antibody to chemotherapy associated with superior OS (HR 0.523). A total of 64.7% patients received further-line therapy, which included a BRAF inhibitor in 17 patients. Targeted therapy associated with very favourable OS (25.1 months).

CONCLUSION

Patients with BRAFV600E-mutated mCRC benefit from the addition of an antibody to first-line chemotherapy. Further-line treatment including a BRAF inhibitor has a dramatic impact on survival.

Content development of the VISION-Cog: a novel tool to assess cognitive impairment in visually impaired older adults in Singapore

OBJECTIVES

Current cognitive screening and diagnostic instruments rely on visually dependent tasks and are, therefore, not suitable to assess cognitive impairment (CI) in visually impaired older adults. We describe the content development of the VISually Independent test battery Of NeuroCOGnition (VISION-Cog)-a new diagnostic tool to evaluate CI in visually impaired older Singaporean adults.

DESIGN

The content development phase consisted of two iterative stages: a neuropsychological consultation and literature review (stage 1) and an expert-panel discussion (stage 2). In stage 1, we investigated currently available neuropsychological test batteries for CI to inform constructions of our preliminary test battery. We then deliberated this battery during a consensus meeting using the Modified Nominal Group technique (stage 2) to decide, via agreement of five experts, the content of a pilot neuropsychological battery for the visually impaired.

SETTING

Singapore Eye Research Institute.

PARTICIPANTS

Stakeholders included researchers, psychologists, neurologists, neuro-ophthalmologists, geriatricians and psychiatrists.

OUTCOME MEASURE

pilot VISION-Cog.

RESULTS

The two-stage process resulted in a pilot VISION-Cog consisting of nine vision-independent neuropsychological tests, including the modified spatial memory test, list learning, list recall and list recognition, adapted token test, semantic fluency, modified spatial analysis, verbal subtests of the frontal battery assessment, digit symbol, digit span forwards, and digit span backwards. These tests encompassed five cognitive domains-memory and learning, language, executive function, complex attention, and perceptual-motor abilities. The expert panel suggested improvements to the clarity of test instructions and culturally relevant test content. These suggestions were incorporated and iteratively pilot-tested by the study team until no further issues emerged.

CONCLUSIONS

We have developed a five-domain and nine-test VISION-Cog pilot instrument capable of replacing vision-dependent diagnostic batteries in aiding the clinician-based diagnosis of CI in visually impaired older adults. Subsequent phases will examine the VISION-Cog's feasibility, comprehensibility and acceptability; and evaluate its diagnostic performance.

Feasibility, comprehensibility and acceptability of the VISION-Cog, a novel tool to assess cognitive impairment in visually impaired older adults: a cross-sectional pilot study in Singapore

OBJECTIVES

We pilot-tested the VISually Independent test battery Of NeuroCOGnition (VISION-Cog) to determine its feasibility, comprehensibility and acceptability in evaluating cognitive impairment (CI) in visually impaired older Asian adults.

DESIGN

The VISION-Cog was iteratively fine-tuned through pilot studies and expert-panel discussion. In the first pilot study (Stage 1), we recruited 15 visually impaired and cognitively normal participants aged ≥60 years to examine the pilot VISION-Cog's feasibility (length of time to administer), comprehensibility (clarity of instructions) and acceptability (participant burden). We then presented the pilot results to the expert panel (Stage 2) who decided via agreement on a revised version of the VISION-Cog. Subsequently, we conducted a second pilot study (Stage 3) on another four participants to ascertain improvement in feasibility, comprehensibility and acceptability of the revised version.

SETTING

Singapore Eye Research Institute.

PARTICIPANTS

Nineteen Asian adults aged ≥60 years with visual impairment (defined as near visual acuity worse than N8) were recruited.

OUTCOME MEASURE

Revised VISION-Cog.

RESULT

The VISION-Cog was deemed feasible, taking approximately 60 min to complete on average. All participants agreed that the test instructions were clear, and the battery did not cause undue discomfort or frustration. The data collector rated all tests as very user-friendly (score of 5/5). Minor modifications to the pilot VISION-Cog were suggested by the panel to improve its safety, clarity of instructions and content validity, which were incorporated and iteratively tested in the second pilot study until no further issues emerged.

CONCLUSIONS

Using an iterative mixed-methods process, we have developed a feasible, comprehensible and acceptable 5-domain and 9-item visually independent VISION-Cog test battery suitable to assist CI diagnosis in older adults with visual impairment. We will assess its diagnostic potential against clinician-based assessment of CI in subsequent phases.

Smaller panel, similar results: genomic profiling and molecularly informed therapy in pancreatic cancer

BACKGROUND

Pancreatic cancer has a dismal prognosis. One reason is resistance to cytotoxic drugs. Molecularly matched therapies might overcome this resistance but the best approach to identify those patients who may benefit is unknown. Therefore, we sought to evaluate a molecularly guided treatment approach.

MATERIALS AND METHODS

We retrospectively analyzed the clinical outcome and mutational status of patients with pancreatic cancer who received molecular profiling at the West German Cancer Center Essen from 2016 to 2021. We carried out a 47-gene DNA next-generation sequencing (NGS) panel. Furthermore, we assessed microsatellite instability-high/deficient mismatch repair (MSI-H/dMMR) status and, sequentially and only in case of KRAS wild-type, gene fusions via RNA-based NGS. Patient data and treatment were retrieved from the electronic medical records.

RESULTS

Of 190 included patients, 171 had pancreatic ductal adenocarcinoma (90%). One hundred and three patients had stage IV pancreatic cancer at diagnosis (54%). MMR analysis in 94 patients (94/190, 49.5%) identified 3 patients with dMMR (3/94, 3.2%). Notably, we identified 32 patients with KRAS wild-type status (16.8%). To identify driver alterations in these patients, we conducted an RNA-based fusion assay on 13 assessable samples and identified 5 potentially actionable fusions (5/13, 38.5%). Overall, we identified 34 patients with potentially actionable alterations (34/190, 17.9%). Of these 34 patients, 10 patients (10/34, 29.4%) finally received at least one molecularly targeted treatment and 4 patients had an exceptional response (>9 months on treatment).

CONCLUSIONS

Here, we show that a small-sized gene panel can suffice to identify relevant therapeutic options for pancreatic cancer patients. Informally comparing with previous large-scale studies, this approach yields a similar detection rate of actionable targets. We propose molecular sequencing of pancreatic cancer as standard of care to identify KRAS wild-type and rare molecular subsets for targeted treatment strategies.

Utilization of the Youth Quitline as an opportunity for an undergraduate nursing students to deliver smoking cessation counseling as their clinical placement: An implementation of a service-learning model

BACKGROUND

Smoking is an important modifiable risk factor of morbidities and mortality. Although healthcare professionals play an important role in smoking cessation, their adoption of such practices is relatively low because of inadequate training. To address this issue, we incorporated a service-learning model to operate the Youth Quitline. Undergraduate nursing students were trained and received supervision while delivering smoking cessation counseling through the Youth Quitline as their clinical placement.

OBJECTIVES

We evaluated the effectiveness of the placement by assessing students' knowledge, attitudes and practices regarding smoking cessation and tobacco control.

DESIGN

One-group pretest-posttest design.

SETTING

Youth Quitline.

PARTICIPANTS

A total of 61 third-year students in a mental health nursing program.

METHODS

Students were required to complete 80 h at the Youth Quitline. The 80 h were divided into 20 sessions; students used four sessions to approach and recruit youth smokers in the community, then provided them with telephone counseling for the rest of the time. Prior to the placement, students attended a 2-day workshop. The outcomes were changes in students' knowledge, attitudes and practices regarding smoking cessation and tobacco control 3 months after the placement compared with baseline.

RESULTS

From January-June 2021, students conducted 105 outreach activities to identify 3142 smokers in the community, and provided telephone counseling for 336 smokers via Youth Quitline. Compared with baseline, significant improvements were observed in students' knowledge, attitudes and practices regarding smoking cessation and tobacco control at 3-month follow-up.

CONCLUSIONS

The clinical placement improved students' knowledge, attitudes and practices regarding smoking cessation and tobacco control, enhancing their competency in providing support to assist smokers to quit in their future practice. Incorporating the service-learning model in existing community-based services can provide additional venues for nursing students to practice. This is particularly important because many venues have restricted access during the COVID-19 pandemic.

O-174 Individualized versus standard FSH dosing in predicted poor responders: an RCT

Study question

Is there a difference in fertility outcomes between individualized or standard FSH dosing in women scheduled for IVF with an expected poor response?

Summary answer

In predicted poor responders (AFC<10) undergoing IVF/ICSI, individualized FSH dosing does not improve ongoing pregnancy rates as compared to a standard FSH dose.

What is known already

Poor responders usually lead to many detrimental effects on IVF outcomes due to low oocyte number and quality which in turn result in low pregnancy outcomes and an increased chance of cycle cancellation. Clinicians often individualize the FSH dose using ovarian reserve tests (ORT), including antral follicle count (AFC), basal FSH (bFSH), and anti-Mullerian hormone (AMH). However, it is unclear whether individualized FSH dosing improves clinical outcomes.

Study design, size, duration

Between March 2019 and April 2020, we performed a single-center, parallel, open-label RCT in women with an AFC<10. A total of 661 women were randomized either to start FSH dosing at 300IU/225IU or 150IU. The primary outcome was live birth attributable to the first ART cycle within 18 months of randomization. In this abstract, we report ongoing pregnancy rates. Live birth date will be available at the meeting.

Participants/materials, setting, methods

Women referred for their first IVF/ICSI cycle, <43 years of age, AFC<10 were approached. A total of 328 women were allocated to the individualized group and 333 women were allocated to the standard group. In the individualized group, women with AFC 1-6 were assigned to 300IU/day (n = 122), while women with AFC 7-9 were assigned to 225IU/day (n = 206). In the standard group, women were assigned 150IU/day. Outcomes were evaluated from an intention-to-treat perspective.

Main results and the role of chance

For ongoing pregnancy rate attributable to the first ART cycle for individualized versus standard dosing was comparable [52.44% vs 46.25%, relative risk (RR): 1.29 (95%CI, 0.94-1.74), P = 0.11]. Biochemical pregnancy rate [62.50% vs 62.16%, RR: 1.01 (95%CI, 0.74-1.39), P = 0.929], clinical pregnancy rate [59.45% vs 58.86%, RR: 1.02 (95%CI, 0.75-1.40), P = 0.877] and multiple pregnancy rate [5.18% vs 5.12%, RR: 1.01 (95%CI, 0.51-2.02), P = 0.971] also did not differ between individualized and standard dosing. There are 24 women who are ongoing pregnancy but do not reach live birth in the completed embryo transfer cycle. The individualized group reported less poor response (31.1% vs 48.7%: P < 0.001), more obtained oocytes (6.80 ± 3.85 vs 5.28 ± 3.22; P < 0.001), less embryos (3.76 ± 2.70 vs 3.16 ± 2.42; P = 0.004), and less good quality embryos (2.61 ± 2.29 vs 2.21 ± 2.05; P = 0.018). When outcomes were compared over the first embryo transfer, ongoing pregnancy rates were 39.0% (128/328) versus 37.2% (124/333), respectively [RR:1.08 (95%CI, 0.79-1.48), P = 0.636], without differences in the other outcomes. There are 7 women who are ongoing pregnancy but do not reach live birth in the first embryo transfer cycle.

Limitations, reasons for caution

Due to the open-label character, potential selective canceling and small dose adjustments of standard dosing were allowed. This abstract reports on ongoing pregnancy. At the meeting, we will present live birth rates.

Wider implications of the findings

In women with predicted poor response, an increased dose does not increase ongoing pregnancy rates. A standard dose of 150IU/day is recommended in these women.

Trial registration number

ChiCTR1900021944

C-39 Utility of Addenbrooke's Cognitive Exam III (Singapore-Chinese Version) for Cognitive Screening and Correlation with Standardized Neuropsychological Tests

Objective

Dementia is a public health priority worldwide. Early screening of cognitive impairment and locating of specific impaired areas are essential for timely intervention and prolonging independence. The commonly-used Mini Mental State Examination (MMSE) is inadequate. Alternatively, the Addenbrooke's Cognitive Exam III (ACE-III) that assesses five domains (attention, memory, verbal fluency, language and visuospatial abilities) is recommended.

Thus, we aim to examine the utility of Singapore-Chinese version (ACE-III-SG-C) for case finding of cognitive impairment, and its correlation with the respective standardized neuropsychological tests.

Methods

22 participants were referred by neurologists for comprehensive neuropsychological assessment at public healthcare institution. Participants were categorized into three groups (No Cognitive Impairment, NCI: 6; Mild Cognitive Impairment, MCI: 9; Dementia: 7). The ACE-III-SG-C and MMSE were administered. ACE-III-SG-C total and individual domain scores were computed.

Results

No significant difference in age and education across three groups. The MMSE scores (F(2,19) = 5.005, p = .018) and ACE-III-SG-C total scores (F(2,19) = 21.296, p < 0.001) were significantly different across three groups. Post hoc comparisons indicated that dementia (p < .001) and MCI (p = 0.046) groups had significantly lower ACE-III-SG-C total scores than NCI group. However, the MMSE scores of the MCI and NCI groups were comparable (p = 0.850). The Modified Boston Naming Test were significantly correlated with ACE-III-SG-C language domain scores (r = .605, p = .003), but not MMSE (r = .400, p = .065).

Conclusions

ACE-III-SG-C demonstrated its usefulness for early screening of MCI and dementia. Its correlation with language test suggested potential detection for disorders with language impairment. Further research is needed to unravel its utility of describing other specific impaired areas.

Serial position effects differ between Alzheimer's and vascular features in mild cognitive impairment

Individuals with mild cognitive impairment (MCI) exhibit varying serial position effect (SPE) performances. The relationship between SPE performance in word list recall and clinical, genetic, and neuroimaging features of MCI requires elucidation. 119 MCI and 68 cognitively normal (CN) participants underwent cognitive assessment, apolipoprotein E (ApoE) genotyping, and volumetric MRI brain scans processed via voxel-based morphometry. A 10-word recall task was used to assess SPE performance in relation to recency and primacy recall. MCI participants were classified as having Good SPE performance (high primacy and recency, Good SPE) or Poor SPE performance (low primacy only, LP-SPE; low recency only, LR-SPE; or both low, Low SPE). Poor SPE participants had reduced grey matter (GM) volumes and increased white matter hyperintensities (WMH) volumes. Participants with LP-SPE demonstrated reduced hippocampal GM volumes and were more likely to be ApoE ε4 carriers. LR-SPE was associated with higher WMH volumes. Presence of both greater WMH volumes and ApoE ε4 resulted in Low SPE. LP-SPE MCI participants had features typical of Alzheimer's disease. LR-SPE MCI was associated with increased WMH volumes, likely representing vascular pathology. SPE profiles are associated with distinct clinical patterns of MCI pathophysiology and could have potential as a clinical marker.

Targeted exome sequencing reveals homozygous TREM2 R47C mutation presenting with behavioral variant frontotemporal dementia without bone involvement

To identify genes associated with frontotemporal dementia (FTD) in South-East Asia, targeted exome sequencing and C9orf72 genotyping was performed in 198 subjects (52 patients with FTD and 146 healthy controls) who were screened for mutations in 12 FTD-associated genes. We detected a homozygous TREM2 R47C mutation in a patient with behavioral variant FTD without bone cysts or bone-associated phenotype. Two novel nonsense GRN mutations in 3 FTD patients from the Philippines were detected, but no known pathogenic mutations in other FTD-associated genes were found. In 45 subjects screened for C9orf72 repeat expansions, no pathogenic expansion (≥30 repeats) was identified, but there was a higher proportion of intermediate length (≥10-29 repeats) alleles in patients compared with controls (8/90 alleles, 8.9% vs. 9/164 alleles, 5.5%). Overall, we detected a mutation rate of 7.7% (4/52 patients) in our cohort. Given recent findings of enrichment of rare TREM2 variants (including R47C) in Alzheimer's disease, it is notable that we detected a homozygous TREM2 R47C carrier presenting with an FTD rather than an Alzheimer's disease phenotype.

[Inflammation of the parathyroid glands]

Inflammation of the parathyroid glands is rare when compared to other endocrine organs. This leads to the use of descriptive terms as well as the lack of a generally accepted classification for inflammatory disorders of the parathyroid glands. This review article proposes that parathyroid inflammation be subdivided morphologically into (a) non-specific lymphocytic infiltration, which is more an expression of damage to small vessels, due to e. g. severe systemic inflammation or myocardial infarction, (b) autoimmunogenic lymphocytic parathyroiditis, (c) nonimmunogenic inflammation caused by granulomatous diseases or infections and (d) invasive sclerosing (peri) parathyroiditis. As only parathyroid glands removed due to hyperparathyroidism and normal parathyroid glands incidentally removed during thyroid surgery are seen almost exclusively in routine histopathology, virtually no information about the morphological correlate of hypoparathyroidism is available.

[Clinical importance of thyroid gland cytology]

The cytological evaluation of fine needle biopsies (FNB) of the thyroid gland crucially depends on a close cooperation between clinicians and cytopathologists. Scintigraphy, sonography as well as clinical data and patient history are necessary for a correct interpretation of the indications for FNB; moreover, these data are of outstanding importance for cytopathologists for the correct interpretation of the cytomorphological findings. This overview describes the present standards in the acquisition, technical workup and cytopathological interpretation of thyroid gland tissue obtained by FNB, particularly focusing on the rapidly growing relevance of additional molecular pathological investigations to increase the diagnostic accuracy of thyroid FNB.

[Thyroid C cells and their pathology: Part 1: normal C cells, - C cell hyperplasia, - precursor of familial medullary thyroid carcinoma]

The C cells (parafollicular) of the human thyroid gland are predominantly located within the thyroid follicles, are of neuroendocrine origin and produce and secrete the peptide hormone calcitonin. Calcitonin is clinically utilized as a screening marker to detect occult medullary thyroid carcinoma (MTC) as well as in the follow-up of patients with MTC. An increase in the number of C cells is designated as C cell hyperplasia (CCH). Neoplastic CCH is caused by an autosomal dominant inherited mutation of the RET protooncogene, which develops into invasive familial MTC in the setting of multiple endocrine neoplasia (MEN) type 2 depending on the location of the mutation in the RET gene with a high variation in latency. According to the current state of knowledge CCH without a germline mutation in the RET protooncogene, designated as non-MEN2-associated CCH, seems to be unrelated to the development of sporadic MTC.

A randomised controlled trial of peri-operative lidocaine infusions for open radical prostatectomy

We allocated 76 men scheduled for radical retropubic prostatectomy to peri‐operative lidocaine 2% or saline 0.9%: a pre‐operative 0.075 ml.kg⁻¹ intravenous bolus; an intra‐operative intravenous infusion at 0.075 ml.kg⁻¹.h⁻¹; and 24 hours' postoperative subcutaneous infusion at 0.075 ml.kg⁻¹.h⁻¹. Lidocaine reduced the postoperative hospital stay by a mean (95% CI) of 1.3 (0.3–2.4) days, p = 0.017, from a mean (SD) of 4.6 (3.2) days with saline. Lidocaine reduced pain at rest during the first 24 postoperative hours by a mean (95% CI) of 1.8 (0.7–2.9) mm.h⁻¹, p = 0.001. Lidocaine reduced 24‐h morphine consumption by a mean (95% CI) of 13.9 (2.2–25.7) mg, p = 0.021, from a mean (SD) of 52.3 (26.9) mg with saline. There were no differences in other outcomes.

[Medullary thyroid carcinoma]

Medullary thyroid carcinoma (MTC) is a very rare malignancy, which arises from parafollicular C cells and accounts for 3-5% of all thyroid cancers. MTC represents a neuroendocrine tumor with a biology that differs considerably from differentiated thyroid cancer. Presence of a RET proto-oncogene germline mutation indicates hereditary C cell disease in the context of multiple endocrine neoplasia type 2 and hence a special treatment algorithm is required. Cure of MTC is only possible through surgery. Calcitonin screening is advocated for early MTC diagnosis and preoperative MTC management stratification. In case of surgically incurable persistent MTC, estimation of calcitonin and CEA doubling time is crucial to assess tumor biology and is complemented by multimodal imaging to assess tumor burden. Treatment decisions in incurable MTC must be carefully balanced with treatment-related morbidity, since MTC may take an indolent course over years.

MDM2 is an important prognostic and predictive factor for platin-pemetrexed therapy in malignant pleural mesotheliomas and deregulation of P14/ARF (encoded by CDKN2A) seems to contribute to an MDM2-driven inactivation of P53

Background:

Malignant pleural mesothelioma (MPM) is a highly aggressive tumour that is first-line treated with a combination of cisplatin and pemetrexed. Until now, predictive and prognostic biomarkers are lacking, making it a non-tailored therapy regimen with unknown outcome. P53 is frequently inactivated in MPM, but mutations are extremely rare. MDM2 and P14/ARF are upstream regulators of P53 that may contribute to P53 inactivation.

Methods:

A total of 72 MPM patients were investigated. MDM2 immunoexpression was assessed in 65 patients. MDM2 and P14/ARF mRNA expression was analysed in 48 patients of the overall collective. The expression results were correlated to overall survival (OS) and progression-free survival (PFS).

Results:

OS and PFS correlated highly significantly with MDM2 mRNA and protein expression, showing a dismal prognosis for patients with elevated MDM2 expression (for OS: Score (logrank) test: P⩽0.002, and for PFS: Score (logrank) test; P<0.007). MDM2 was identified as robust prognostic and predictive biomarker for MPM on the mRNA and protein level. P14/ARF mRNA expression reached no statistical significance, but Kaplan–Meier curves distinguished patients with low P14/ARF expression and hence shorter survival from patients with higher expression and prolonged survival.

Conclusions:

MDM2 is a prognostic and predictive marker for a platin–pemetrexed therapy of patients with MPMs. Downregulation of P14/ARF expression seems to contribute to MDM2-overexpression-mediated P53 inactivation in MPM patients.

HER2 expression and markers of phosphoinositide-3-kinase pathway activation define a favorable subgroup of metastatic pulmonary adenocarcinomas

OBJECTIVES

Pulmonary adenocarcinomas (ADC) can be sub-grouped based on dominant oncogenic drivers. EGFR mutations define an entity of metastatic ADC with favorable prognosis and high susceptibility to EGFR tyrosine kinase inhibition. In contrast, the clinical impact of additional ERBB family members in ADC is less defined. To this end we prospectively studied HER2 expression, gene amplification, and mutation in relation to outcome of patients with advanced or metastatic ADC.

MATERIALS AND METHODS

Diagnostic tumor biopsies from 193 sequential patients with stage III/IV ADC were prospectively studied for HER2 expression by immunohistochemistry (IHC). Cases with IHC scores 2+ or 3+ were analyzed by HER2 chromogenic in situ hybridization (CISH), and sequencing of HER2 exons 20 and 23. Additional prospectively determined biomarkers included PTEN, cMET, pAKT, and pERK expression, KRAS, EGFR, BRAF and PIK3CA mutations, and ALK fluorescence ISH (FISH).

RESULTS AND CONCLUSION

HER2-IHC was feasible in 176 (91.2%) cases. Of 53 (30%) cases with IHC scores 2+/3+, 45 (85%) could be studied by CISH and 34 (64%) by sequencing. The lower number of HER2-mutational analyses resulted from exhaustion of tumor tissue and DNA following mutational analysis of KRAS, EGFR, BRAF and PIK3CA. HER2 amplification was detected in 4 cases (2.3%), while no mutation was found. HER2 expression correlated with expression of pAKT and cMET. Expression of HER2 and pAKT was associated with favorable overall survival in stage IV disease. HER2-expressing ADC more frequently harbored KRAS mutations, while HER2 expression was absent in all 4 cases with BRAF mutation. HER2-IHC was not predictive of HER2 gene amplification or mutation, which both were rare events in prospectively studied patients with advanced or metastatic ADC. Expression of HER2 and pAKT define a population of patients with stage IV ADC with a distinct disease course, who could benefit from specifically tailored pharmacotherapies.

Microstructural analysis of Co-Cr dental alloy at the metal-porcelain interface: a pilot study

OBJECTIVE

The purpose of the study was to observe whether conventional porcelain firings had an effect on the underlying microstructure of cobalt-chromium alloys used in porcelain-fused-to-metal systems.

METHODS

One as cast (non-veneered) and two porcelain veneered Co-Cr specimens layered with and without tungsten(W)-metal conditioner were manufactured and analysed. Electron backscatter diffraction was used to determine the crystal structures and grain size across the porcelain-fused-to-metal interface.

RESULTS

No difference was found in the microstructure of the alloy in both with and without W-metal conditioner. For the porcelain fired specimens, disparately sized granular structures were observed adjacent to the metal-porcelain interfaces compared to the bulk of the metal. Ellipsoid shaped grains at the alloy surface ranged between 1-11 μm in diameter and averaged 2.70 μm (SD: 2.17 μm) for the specimen layered with W-metal conditioner and 2.86 μm (SD: 1.85 μm) for the specimen layered without W-metal conditioner. Grains located in the bulk were > 200 μm with dendritic-like features. The depth of the fine grain structure adjacent to the surface had an average depth of 15 μm. The crystal structure of the surface layer was found to be predominantly hexagonal close-packed whereas the underlying bulk was a mixture of both face-centered cubic and hexagonal close-packed phases. For the as cast specimen, similar large grains of over 200 μm was observed but exhibited no dendritic like features. In addition, no fine grains were observed at the surface region of the as cast alloy.

CONCLUSION

Conventional porcelain firings altered the interfacial and bulk microstructure of the alloy while the presence of the W-metal conditioner had no influence on the underlying alloy microstructure.

[Role of pretherapeutic biomarkers in lung cancer with special regards to bronchoscopic procedures]

Molecular biomarkers are becoming increasingly significant in the workup of lung carcinoma patients. They assist in diagnosis, selecting the most adequate therapy and determining prognosis. Obtaining blood based biomarkers or volatile markers in exhaled breath may provide a less invasive method in the future. For the time being, bronchoscopy is still the method of choice to obtain specimen and assess tissue based biomarkers. The techniques how specimen are collected and processed for analysis are of paramount importance.

Impact of human papilloma virus infection on the response of head and neck cancers to anti-epidermal growth factor receptor antibody therapy

Infection with human papillomaviruses (HPVs) characterizes a distinct subset of head and neck squamous cell cancers (HNSCCs). HPV-positive HNSCC preferentially affect the oropharynx and tonsils. Localized HPV-positive HNSCCs have a favorable prognosis and treatment outcome. However, the impact of HPV in advanced or metastatic HNSCC remains to be defined. In particular, it is unclear whether HPV modulates the response to cetuximab, an antibody targeting the epidermal growth factor receptor (EGFR), which is a mainstay of treatment of advanced HNSCC. To this end, we have examined the sensitivity of HPV-positive and -negative HNSCC models to cetuximab and cytotoxic drugs in vitro and in vivo. In addition, we have stably expressed the HPV oncogenes E6 and E7 in cetuximab-sensitive cancer cell lines to specifically investigate their role in the antibody response. The endogenous HPV status or the expression of HPV oncogenes had no significant impact on cetuximab-mediated suppression of EGFR signaling and proliferation in vitro. Cetuximab effectively inhibited the growth of E6- and E7-expressing tumors grafted in NOD/SCID mice. In support, formalin-fixed, paraffin-embedded tumor samples from cetuximab-treated patients with recurrent or metastatic HNSCC were probed for p16^INK4a expression, an established biomarker of HPV infection. Response rates (45.5% versus 45.5%) and median progression-free survival (97 versus 92 days) following cetuximab-based therapy were similar in patients with p16^INK4A-positive and p16^INK4A-negative tumors. In conclusion, HPV oncogenes do not modulate the anti-EGFR antibody response in HSNCC. Cetuximab treatment should be administered independently of HPV status.

Attitudes in the management of patients with dementia: comparison in doctors with and without special training

OBJECTIVE

To explore by postal survey the different attitudes towards management of patients with dementia in physicians with and without dementia training.

METHODS

A questionnaire was sent to 7669 members of the Hong Kong Medical Association, which represents 61% of all locally registered medical practitioners.

RESULTS

In all, 448 questionnaires were returned (response rate: 6%). Among these, there were 34 questionnaires with missing data or the respondents indicated that they were either retired or not in practice. Therefore, only 414 questionnaires were used in analysis. Among these, 82 (20%) had received dementia training, 310 (75%) had not, and 22 (5%) did not indicate their choice. Twelve statements were used to explore various attitudes about dementia care. Exploratory factor analysis showed that there were 2 strong factors: confidence and negative views. The mean scores of these 2 factors were significantly different in physicians with and without dementia training. With respect to management of patients with dementia, dementia-trained physicians had significantly greater confidence (mean [standard deviation (SD)] = 5.21 [1.34]) than those who were non-trained (mean [SD] = 3.57 [1.40]; p < 0.001). Conversely, non-trained physicians had significantly stronger negative views (mean [SD] = 3.89 [1.24]) on dementia care than those who were trained (mean [SD] = 3.12 [1.36]; p < 0.001).

DISCUSSION

These findings suggest that providing a certain level of dementia care training for physicians is an effective way to improve confidence in managing patients with dementia, and thereby decrease possible negative attitudes towards such care.