Abstract 664: Analytical validation and clinical utility of an immunohistochemical PD-L1 diagnostic assay for treatment with durvalumab in urothelial carcinoma patients

Background: A high quality programmed cell death ligand-1 (PD-L1) diagnostic may help to identify patients (pts) most likely to respond to anti-PD-L1/programmed cell death-1 (PD-1) therapy. Here we describe a PD-L1 immunohistochemical (IHC) diagnostic test developed for urothelial carcinoma (UC) pts treated with durvalumab.

Methods: The IHC assay uses an anti-human PD-L1 rabbit mAb optimized for detection of both tumor cell (TC) and tumor-associated immune cell (IC) PD-L1 expression with the OptiView DAB IHC Detection Kit on the automated VENTANA BenchMark ULTRA platform. The assay was validated for intended use in UC formalin-fixed, paraffin-embedded samples in a series of studies that addressed sensitivity, specificity, robustness and precision and implemented in Study CD-ON-MEDI4736-1108 (NCT01693562). Pts were evaluated using the VENTANA PD-L1 (SP263) Assay at a prespecified PD-L1 expression cut-off. Efficacy was analyzed in pts with PD-L1 low/negative (defined as TC <25% and IC <25%) UC and in pts with PD-L1 high (defined as TC ≥25% or IC ≥25%) UC.

Results: The VENTANA PD-L1 (SP263) Assay met all the predefined acceptance criteria (average positive agreement and average negative agreement >85%), showing analytical specificity, sensitivity and precision. It demonstrated ≥97% and ≥85% inter-reader precision agreement for TC and IC respectively. For intra-reader precision, it demonstrated >96% and >87% agreement for TC and IC respectively. For intra-day performance, the assay demonstrated ≥96% agreement for TC and IC and for inter-day performance, it demonstrated ≥98% and 100% agreement for TC and IC respectively. Precision studies for inter-antibody lot, inter-detection kit lot and intra-platform demonstrated >97% agreement for both TC and IC. Inter-laboratory testing was performed at 3 external laboratories and demonstrated an overall agreement rate of 92.3%. The VENTANA PD-L1 (SP263) Assay was implemented in Study CD-ON-MEDI4736-1108 and durvalumab demonstrated clinical activity and durability of response in both PD-L1 high and PD-L1 low/negative subgroups, yet with different response rates. In addition, given the high negative predictive value of the assay, it is especially helpful in evaluating the likelihood of response to durvalumab; pts who were classified as PD-L1 high with the VENTANA PD-L1 (SP263) Assay tended to have a higher objective response rate per RECIST v1.1 than pts who were PD-L1 low/negative.

Conclusions: These data show that determination of PD-L1 expression in TC and IC in UC pts using the VENTANA PD-L1 (SP263) Assay is precise and highly reproducible and highlight the utility of the assay in a clinical setting. The VENTANA SP263 Assay is especially helpful in informing pts and physicians on the likelihood of response to durvalumab, but not for the purpose of restricting treatment to only PD-L1 high pts.

Citation Format: M Zajac, A M. Boothman, Y Ben, A Gupta, J Antal, X Jin, A Nielsen, G Manriquez, C Barker, P Wang, P Patil, N Schechter, M Rebelatto, J Walker. Analytical validation and clinical utility of an immunohistochemical PD-L1 diagnostic assay for treatment with durvalumab in urothelial carcinoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 664. doi:10.1158/1538-7445.AM2017-664

Abstract 656: PD-L1 expression in primary lesions vs metastatic sites and by demographics in advanced urothelial carcinoma samples

Background: Determination of programmed cell death ligand-1 (PD-L1) expression levels in tumors may help physicians understand which patients (pts) are most likely to respond to anti-PD-1/PD-L1 therapies in urothelial carcinoma (UC). Understanding the impact of different sample types and demographics on PD-L1 expression is important to determine suitability of tumor biopsies for testing.

Methods: As of July 24, 2016, 363 pts screened in the UC cohort of Study CD-ON-MEDI4736-1108 (NCT01693562) had tissue available for analysis and 47 pts had provided paired primary and metastatic samples. FFPE samples were tested in a central laboratory with the VENTANA PD-L1 (SP263) Assay using a BenchMark ULTRA instrument. Pts were classified as having either PD-L1 high (PD-L1 expression ≥25% either on tumour cells [TC] or immune cells [IC]) or PD-L1 low/negative (<25% on TC and IC) tumors. PD-L1 high prevalence was reported in primary vs metastatic sites, and by age, sex and race.

Results: PD-L1 status was evaluable for 332/363 (91.5%) pts (175/332 [52.7%] PD-L1 high and 157/332 [47.3%] PD-L1 low/negative) whose UC specimens were tested (intent to diagnose [ITD] population). Overall percentage agreement between paired primary and metastatic samples, based on combined TC/IC scoring ≥25%, was 74.5% (95% CI 59.7 - 86.1%). In the ITD population, using only the samples from which patient PD-L1 expression status was determined, PD-L1 high prevalence in primary and metastatic samples was 57.1% and 50.9% respectively (p=0.343, not significant). The proportion of pts with PD-L1 high status was not enriched in any demographic group (Table).

Conclusions: Initial data from UC pts in Study 1108 showed similar PD-L1 high prevalence in primary and metastatic lesions and good concordance between paired primary and metastatic samples. These results build optimism that samples obtained from either location could be used to determine PD-L1 status. Further data are needed to confirm these findings.

Patients screened for UC cohort with evaluable PD-L1 result - ITD population (n = 332)ParameterPD-L1 high, n (%)P valueAge, years<65 (n=131)73 (55.7%)0.438≥65 (n=201)102 (50.8%)SexMale (n=236)127 (53.8%)0.610Female (n=96)48 (50.0%)RaceAsian (n=52)23 (44.2%)Asian vs White: 0.406Black or African American (n=10)6 (60.0%)White (n=218)113 (51.8%)Other (n=9)4 (44.4%)

Citation Format: M Zajac, A M. Boothman, Y Ben, A Gupta, X Jin, J Antal, A Sharpe, M Scott, M Rebelatto, J Walker. PD-L1 expression in primary lesions vs metastatic sites and by demographics in advanced urothelial carcinoma samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 656. doi:10.1158/1538-7445.AM2017-656

Affective concordance in couples: a cross-sectional analysis of depression and anxiety consultations within a population of 13,507 couples in primary care

BACKGROUND

Depression and anxiety are common and have a significant impact on the individual and wider society. One theory proposed to explain a heightened risk for depression and anxiety is affective concordance in couples (e.g. influence of shared mood states, shared health beliefs). Whilst research has shown concordance for severe psychiatric illnesses and general mood in couples, little attention has been given to concordance for common psychiatric conditions such as depression and anxiety. The aims of this study were to test affective concordance in couples and examine potential influences on concordance.

METHODS

Study design is a 1-year cross-sectional study of anxiety and depression consultations in primary care. Data were obtained from a validated primary care database of recorded consultations. Outcome was the presence of an anxiety or depression Read Code (GP recorded reason for consultation) in the female (within the couple dyad), and exposure was a recorded Read Code of anxiety or depression in the male. Logistic regression was used to test associations with odds ratios (OR) and 95% confidence intervals (95% CI) reported. Statistical adjustment was carried out on potential influences of concordance; age, environment (deprivation), healthcare behaviour (consultation frequency), and comorbidity.

RESULTS

A population of 13,507 couples were identified in which 927 people consulted for anxiety and 538 for depression. Logistic regression showed a 3 times increase in odds of an anxiety consultation in females if their male partner had also consulted OR 2.98 (95% CI 2.15 to 4.13). For depression females were over 4 times the odds of consulting if their male partner had also consulted OR 4.45 (95% CI 2.79 to 7.09). Adjustment within a multivariable model showed some reduction in odds; concordant anxiety was reduced to 2.5 times odds OR 2.48 (95%CI 1.76 to 3.50) and depression reduced to OR 3.39 (2.07 to 5.54).

CONCLUSION

Results show significant associations for affective concordance in couples. Factors influencing concordance are comorbidity and environmental factors, however reasons for deciding to consult (positive or negative) are unknown. This study highlights the patients' social context as a factor in consultations for anxiety and depression and gives support to the consideration of the patient's household as an influence on mental health.

Microbiological problems and biofilms associated with Mycobacterium chimaera in heater-cooler units used for cardiopulmonary bypass

The role of heater-cooler units (HCUs) in the transmission of Mycobacterium chimaera during open heart surgery has been recognized since 2013. Subsequent investigations uncovered a remarkable global outbreak reflecting the wide distribution of implicated devices. HCUs are an essential component of cardiopulmonary bypass operations and their withdrawal would severely affect capacity for life-saving cardiac surgery. However, studies have demonstrated that many HCUs are contaminated with a wide range of micro-organisms, including M. chimaera and complex biofilms. Whole genome sequencing of M. chimaera isolates recovered from one manufacturer's HCUs, worldwide, has demonstrated a high level of genetic similarity, for which the most plausible hypothesis is a point source contamination of the devices. Dissemination of bioaerosols through breaches in the HCU water tanks is the most likely route of transmission and airborne bacteria have been shown to have reached the surgical field even with the use of ultraclean theatre ventilation. Controlling the microbiological quality of the water circulating in HCUs and reducing biofilm formation has been a major challenge for many hospitals. However, enhanced decontamination strategies have been recommended by manufacturers, and, although they are not always effective in eradicating M. chimaera from HCUs, UK hospitals have not reported any new cases of M. chimaera infection since implementing these mitigation strategies. Water safety groups in hospitals should be aware that water in medical devices such as HCUs may act as a vector in the transmission of potentially fatal water-borne infections.

Brain Development in Fetuses of Mothers with Diabetes: A Case-Control MR Imaging Study

BACKGROUND AND PURPOSE

Offspring exposed to maternal diabetes are at increased risk of neurocognitive impairment, but its origins are unknown. With MR imaging, we investigated the feasibility of comprehensive assessment of brain metabolism (¹H-MRS), microstructure (DWI), and macrostructure (structural MRI) in third-trimester fetuses in women with diabetes and determined normal ranges for the MR imaging parameters measured.

MATERIALS AND METHODS

Women with singleton pregnancies with diabetes (n = 26) and healthy controls (n = 26) were recruited prospectively for MR imaging studies between 34 and 38 weeks' gestation.

RESULTS

Data suitable for postprocessing were obtained from 79%, 71%, and 46% of women for ¹H-MRS, DWI, and structural MRI, respectively. There was no difference in the NAA/Cho and NAA/Cr ratios (mean [SD]) in the fetal brain in women with diabetes compared with controls (1.74 [0.79] versus 1.79 [0.64], P = .81; and 0.78 [0.28] versus 0.94 [0.36], P = .12, respectively), but the Cho/Cr ratio was marginally lower (0.46 [0.11] versus 0.53 [0.10], P = .04). There was no difference in mean [SD] anterior white, posterior white, and deep gray matter ADC between patients and controls (1.16 [0.12] versus 1.16 [0.08], P = .96; 1.54 [0.16] versus 1.59 [0.20], P = .56; and 1.49 [0.23] versus 1.52 [0.23], P = .89, respectively) or volume of the cerebrum (243.0 mL [22.7 mL] versus 253.8 mL [31.6 mL], P = .38).

CONCLUSIONS

Acquiring multimodal MR imaging of the fetal brain at 3T from pregnant women with diabetes is feasible. Further study of fetal brain metabolism in maternal diabetes is warranted.

Formalin disinfection of prostate biopsy needles may reduce post-biopsy infectious complications

BACKGROUND

We sought to determine whether formalin disinfection of prostate biopsy needles between cores reduces post-biopsy urinary tract infections (UTIs).

METHODS

We reviewed a single-surgeon experience of transrectal prostate biopsies from 2010 to 2014. Biopsies were performed in either an operative suite, where 10% formalin was used to disinfect the needle tip between each biopsy core, or an outpatient clinic, where formalin was not used. Our primary outcome was post-biopsy UTI rates, defined as a positive urine culture within 30 days of biopsy. Infection severity was characterized by the need for admission. Patient demographics, prostate size, prior biopsies, prior UTIs, pre-biopsy antibiotics and cultures and post-biopsy cultures were analyzed. Logistic regression was used to assess predictors of post-biopsy UTIs. Statistical significance was defined as P<0.05.

RESULTS

A total of 756 patients were included for analysis, including 253 who received formalin disinfection and 503 who did not. Of these, 32 patients (4.2%) experienced post-biopsy UTIs, with 8 requiring admission (all without formalin use). Infection rates were more than double in the group that did not receive formalin (5.2% vs 2.3%, P=0.085). More patients in the formalin group had undergone prior biopsies (73.9% vs 31.8%, P<0.001). On multivariable analysis, prior UTI (odds ratio (OR) 3.77, P=0.006) was a significant predictor for post-biopsy infection, whereas formalin disinfection trended towards a protective effect (OR 0.41, P=0.055).

CONCLUSION

Infectious complications following prostate biopsy may be mitigated by the use of formalin disinfection of the biopsy needle between cores.

Bipartite Atlas and Hypertrophy of its Anterior Arch

On the lateral cervical spine radiographs of a 60-year-old woman complaining of neck pain, diffuse hyperostosis or calcification was present anterior to the anterior arch of the atlas. CT of atlas revealed it to be bipartite and the hyperostosis to be due to hypertrophy of its anterior arch. We report this as a new sign associated with a bipartite atlas.

Koilonychia: an update on pathophysiology, differential diagnosis and clinical relevance

Koilonychia, a concave nail dystrophy, has multiple aetiologies and may be hereditary, acquired or idiopathic. Within dermatology, koilonychia is often a manifestation of an inflammatory dermatosis such as psoriasis or lichen planus, or a sign of onychomycosis. Other disease associations include iron store abnormalities, Plummer-Vinson Syndrome, nutritional deficiencies and occupational or traumatic aetiologies. In young children, koilonychia of the toenails is commonly transient and idiopathic, although familial and syndromic cases are reported. The dermatologist must be aware of the potential cutaneous and systemic associations with koilonychia in order to guide appropriate workup, treatment and/or referral. An algorithm for evaluation of koilonychia is presented along with discussion of common causes of koilonychia and a comprehensive list of all known associations.