Abstract P5-03-10: Development of a novel HER2 testing strategy, using image-based cell-sorting to isolate pure cell populations from FFPE upstream of FISH

Fluorescent in Situ Hybridization (FISH) guidelines defined by American Society of Clinical Oncology (ASCO) and the College of American Pathologists for determining HER2 status are set to improve accuracy and usefulness as a diagnostic marker in breast cancer. Despite these guidelines, many factors can influence HER2 testing results such as sample preparation, assay-conditions and interpretation of test results due to heterogeneous breast cancer samples. In this multi-site study, sample preparation was carried out using the DEPArray™ to recover pure tumor cell populations from formalin-fixed, paraffin-embedded (FFPE) breast tumor samples. We then compared HER2/CEP17 ratios obtained from the DEPArray™ processed samples from each laboratory to routine FISH on tissue sections.

Methods: Eight breast FFPE tumor tissue biopsies were obtained from commercial tissue banks. From the paraffin tissue blocks, four consecutive tissue curls (each 50 microns thick) were prepared. One curl from each of the 8 patient samples was distributed to four different laboratories for analysis following DEPArray™ based sample preparation. After an initial disassociation of each curl into a single-cell suspension, intact cells were sorted and then recovered based on cytokeratin/ vimentin/DAPI staining using the DEPArray™. Cytokeratin+/Vimentin-/DAPI+ tumor (~250) and Cytokeratin-/Vimentin+/DAPI+ stromal (~250) recovered cells were then deposited onto glass slides prior to standard dual-color HER2/CEP17 FISH analysis for comparison to conventional HER2 FISH result.

Results: Serially sectioned breast tumors from 8 negative/positive cases: 7 infiltrating ductal carcinoma (IDC) and 1 metastatic carcinoma were studied. All four sites demonstrated 100% concordance between FISH results compared to the conventional HER2 FISH result. Overall, >60% of DEPArray™ isolated cells were recovered from FFPE samples that ranged from 1- 15 years of age and reported to contain 60% to 80% tumor content. The use of pure sorted cells permitted the accurate determination of HER2 amplification status in only the tumor cells while the stromal cells consistently yielded a more normalized ratio of HER2 to centromere 17.

Conclusion: The preliminary results of this multi-site study demonstrate that use of DEPArray™ for sorted pure populations is reproducible as well as reliable method for subsequent analysis of HER2 by FISH on FFPE derived tumor cells. Given that traditional FFPE-based HER2 FISH results may be influenced by the tissue sectioning procedure, tissue heterogeneity and/or the scattering of few HER2 amplified tumor cells among normal stromal cells. The DEPArray™ allows analysis of immunofluorescence images and DNA content to isolate and recover pure and intact cell populations. This isolation of pure cell populations prior to FISH analysis is attractive for achieving precise determination of HER2 status on equivocal cases. A more formal analytical validation of this approach through CLIA is currently underway.

Citation Format: Gerber A, Konig L, Millner L, Strotoman L, Khurana A, Kasimir-Bauer S, Moore MW, Cotter PD, Bischoff F. Development of a novel HER2 testing strategy, using image-based cell-sorting to isolate pure cell populations from FFPE upstream of FISH [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-03-10.

A comparison of the psychological burden of PET/MRI and PET/CT scans and association to initial state anxiety and previous imaging experiences

OBJECTIVE

To investigate the level of psychological burden experienced by patients undergoing positron emission tomography (PET)/MRI scanning compared with PET/CT.

METHODS

100 adult patients referred for PET/CT and underwent PET/MRI scanning were eligible. Initial state, psychological burden of PET/CT and PET/MRI, scan satisfaction and preference were assessed using a purpose-designed questionnaire, comprising 61 five-point Likert scale questions and a three-point tick box question indicating preference between PET/CT and PET/MRI. State anxiety was assessed using the state portion of the State Trait Anxiety Inventory. Wilcoxon signed-rank tests compared psychological burden experienced by participants following PET/CT and PET/MRI scan.

RESULTS

A greater level of psychological burden was experienced by patients during PET/MRI than PET/CT p ≤ 0.001, consistent with patients' preference for PET/CT over PET/MRI (p = 0.013). There was a significant relationship between PET/CT psychological burden and initial state (r = 0.386, p ≤ 0.001). No significant relationship was identified between Initial state and psychological burden of PET MRI (r = -0.089; p = 217). There was a significant relationship between psychological burden of PET/CT and PET/MRI (r = 0.354; p = 0.001).

CONCLUSION

Patients' experience increased psychological burden during PET/MRI compared with PET/CT. Previous scanning experiences and patients' interactions prior to and during PET/MRI improved patient satisfaction. Interventions could be implemented to improve imaging outcome.

ADVANCES IN KNOWLEDGE

This study provides evidence for the increased psychological burden of PET/MRI compared with PET/CT, and that people prefer the PET/CT procedure. We have shown that the patients who expressed a preference for PET/MRI demonstrated significantly lower psychological burden for that procedure than those that preferred PET/CT, which indicates that the benefit of reduced psychological burden could be facilitated by an appropriate intervention.

Aequorin variants with improved bioluminescence properties

The photoprotein aequorin has been widely used as a bioluminescent label in immunoassays, for the determination of calcium concentrations in vivo, and as a reporter in cellular imaging. It is composed of apoaequorin (189 amino acid residues), the imidazopyrazine chromophore coelenterazine and molecular oxygen. The emission characteristics of aequorin can be changed by rational design of the protein to introduce mutations in its structure, as well as by substituting different coelenterazine analogues to yield semi-synthetic aequorins. Variants of aequorin were created by mutating residues His16, Met19, Tyr82, Trp86, Trp108, Phe113 and Tyr132. Forty-two aequorin mutants were prepared and combined with 10 different coelenterazine analogues in a search for proteins with different emission wavelengths, altered decay kinetics and improved stability. This spectral tuning strategy resulted in semi-synthetic photoprotein mutants with significantly altered bioluminescent properties.

Health status and sociodemographic characteristics of adults receiving a cystic fibrosis diagnosis after age 18 years

OBJECTIVES

An increasing percentage of cystic fibrosis (CF) diagnoses are occurring in adulthood. The purpose of this study was to explore how age at diagnosis may be associated with selected disease and sociodemographic characteristics.

DESIGN

The 1996 Cystic Fibrosis Foundation (CFF) Patient Registry data were analyzed to test for associations between age at diagnosis and selected variables. All cases involved individuals > or = 18 years who were represented in the CFF Patient Registry for 1996. Patients were assigned to one of two groups: those diagnosed with CF after age 18 years (n = 786) and those diagnosed before 18 years (n = 6,641).

RESULTS

In 1996, the incidence of late diagnosis was 7.8%, and the prevalence was 10.9%. The mean age of late diagnosis was 27 years. Respiratory symptoms most frequently led to late diagnosis. Patients receiving a late CF diagnosis were less likely to have alleles for Delta F508. There was no correlation between age at diagnosis and percent predicted FEV(1), although patients in the late-diagnosis group were an average of 10 years older than those in the early-diagnosis group. Late diagnosis was associated with fewer complications, fewer hospitalizations, less oxygen use, fewer courses of home IV treatment, and less enzyme use. Women were most often diagnosed late. Men displayed more diversity in conditions leading to diagnosis. Psychosocially, those patients receiving late diagnoses were more likely to be college graduates, married, and employed full time. For those adults who died in 1996, there was a positive association between their age at diagnosis and age at death.

CONCLUSION

Those patients diagnosed with CF as adults differ, both medically and psychosocially, from those diagnosed at a younger age; these differences have implications for diagnosis, treatment, and education.

Modeling adherence to colorectal cancer screening

BACKGROUND

An explanatory framework referred to as the Preventive Health Model was used to identify factors associated with prospective adherence to colorectal cancer screening.

METHODS

Data on sociodemographic, psychosocial, social influence, and program factors were collected via telephone survey for 501 older adult members of an independent practice association-type health maintenance organization. Subjects were later mailed fecal occult blood tests for completion and return. Adherence was defined as the return of the tests within 90 days.

RESULTS

Structural analysis shows that for men (N = 145), perceived self-efficacy (OR = 1.4), salience and coherence of testing (OR = 2.3 for a 5-point increment on a 30-point scale), and exposure to health education interventions (OR = 6.8) were significant independent predictors of intention to adhere and of adherence. Among women (N = 185), predictors were age (OR = 1.8) and salience and coherence of testing (OR = 1.8 for a 5-point increment on a 30-point scale).

CONCLUSIONS

These findings indicate that for both men and women, adherence is influenced strongly by the extent to which the behavior is judged to make sense in everyday life. It also appears that additional education and encouragement may persuade men and younger women to participate in screening.

Women's health issues: a review of the current literature in the social work journals, 1985-1992

To assess the ways in which social work is addressing issues in women's health care, the profession's journals from 1985-1992 were searched, yielding 36 articles. Over half addressed issues of reproduction and sexuality including pregnancy, family planning, abortion, substance abuse in pregnancy, and fetal protection policies. Remaining articles addressed medical diagnoses; including AIDS/HIV/STDs, cancer, illnesses associated with aging, PMS, Turner's Syndrome, and chronic fatigue syndrome. Foci, methodologies, and recommendations are discussed and the authors critically analyze the articles' reflections of the status of women's health as a social work concern.

Screening for colorectal neoplasia: physicians' adherence to complete diagnostic evaluation

This prospective study was done in a health maintenance organization colorectal cancer screening program to determine whether 166 persons found to have abnormal fecal occult blood test results typically underwent complete diagnostic evaluation (i.e., either colonoscopy or barium enema x-ray plus flexible sigmoidoscopy). Chart audit data show that 137 (82%) subjects contacted a physician to discuss follow-up. A complete diagnostic evaluation was recommended to only 52 (38%) patients who talked with a physician. Forty-two (81%) patients who were advised to get a complete diagnostic evaluation actually complied. Significant differences in clinical findings were observed for patients who did and did not have a complete diagnostic evaluation.

Adherence to continuous screening for colorectal neoplasia

Continuous screening is defined as the periodic provision of an opportunity for diagnostic testing to a population of individuals who are asymptomatic and at increased risk for disease. If screening is offered periodically irrespective of response to an earlier screening invitation, this situation may be referred to as serial screening. When continuous screening is made available only to individuals who had tested previously, population member response is referred to as repeat screening. This study assessed adherence to serial- and repeat-colorectal cancer screening among older adult members of an independent practice association-type health maintenance organization (HMO) in two consecutive rounds of screening. In the first screening round, fecal occult blood tests (FOBTs) were sent to 1,565 subjects who were randomly assigned to receive usual care or behavioral interventions intended to encourage testing. Overall, 647 (41%) subjects completed and returned their tests. In the second screening round, FOBTs were mailed again to all subjects; however, the interventions were discontinued. Logistic regression analysis results shows that first-round testing was a significant independent predictor of serial adherence for subjects older than 65 years of age (odds ratio[OR] = 10.8) and those younger than 65 years of age (OR = 10.9); and a significant negative association between exposure to first-round intervention and serial adherence (OR = 0.5) was found among younger subjects. Among first-round adherers, age was significantly and positively related to repeat adherence (OR = 1.6). However, exposure to first-round intervention and having an abnormal FOBT result were significantly and negatively associated with repeat adherence (OR = 0.5 and OR = 0.4, respectively). The results of this study reported here indicate that previous screening is a strong predictor of serial adherence, and special efforts may be required to achieve high levels of serial and repeat adherence among younger adults. Additional research is needed to understand why persons with abnormal screening test results are unlikely to engage in repeat screening.

Behavioral interventions to increase adherence in colorectal cancer screening

This investigation was a randomized controlled trial to determine the impact of health education interventions on the return of mailed fecal occult blood (FOB) tests (FOBT adherence) in a colorectal cancer screening program. The study sample included 2,201 men and women aged 50 to 74 years who were members of an Independent Practice Association (IPA)-type health maintenance organization (HMO). Subjects were randomly assigned to a "usual care" Control Group (advance letter, screening kit, reminder letter), and Treatment Groups 1 (usual care + reminder call), 2 (usual care + self-held screening booklet + reminder call), or 3 (usual care + self-held screening booklet + instruction call + reminder call). Bivariate analysis revealed significant differences in adherence (P less than .001) across study groups: Control Group (27%), Group 1 (37%), Group 2 (37%), Group 3 (48%). In addition, a significant positive association between age and adherence (P less than .001) was found. Logistic regression analysis revealed an interaction between sex and treatment. Adherence among men in all treatment groups increased significantly (P less than .0001) in relation to Control Group males. Men in Group 3 also were more likely to adhere than those in Group 2 (P less than .01) or Group 1 (P less than .01). Among women, adherence was significantly higher in Group 3 than in Group 2 (P less than .03), Group 1 (P less than .025), or the Control Group (P = .0008). The primary reason cited for nonadherence was perceived inconvenience of the FOB testing procedure.