Impact of mobilization regimen on multiday collection of peripheral blood CD34+ cells by large volume leukapheresis.

BACKGROUND: The collection yield of hematopoietic progenitors cell (HPC) by leukapheresis is critical for a successful transplantation, which often requires multiday collections to achieve the collection goal. STUDY DESIGN AND METHODS: Collection procedures of 181 patients who underwent leukapheresis for more than 1 day were reviewed. Patients were separated into six groups based on the mobilization regimen: G-CSF on day 1 (D1) and day 2 (D2) (G-G); G-CSF on D1 and G-CSF and plerixafor on D2 (G-GP); G-CSF and plerixafor on day D1 and D2 (GP-GP); G-CSF and plerixafor on D1 and G-CSF on D2 (GP-G); chemotherapy and G-CSF on D1 and D2 (GC-GC); and chemotherapy, G-CSF, and plerixafor on D1 and D2 (GCP-GCP). Patient's pre-collection CD34 count (pre-CD34) on D1 and D2 were compared in the same individual and among groups. RESULTS: We found D2 pre-CD34 were significantly decreased in G-G, GP-G, and GP-GP groups and significantly increased in G-GP group (p < .001) using a repeated measures ANOVA analysis. D2 pre-CD34 remained at similar levels as D1 in GC-GC and GCP-GCP groups. A multiple regression analysis showed that the mobilization regimen was the only factor that significantly affected pre-CD34 D2/D1 ratio (p < .001). There was a significant difference in the pre-CD34 D2/D1 ratio (p < .001) among these six groups with the lowest in GP-G group (0.40 ± 0.45), and the highest in G-GP group (2.35 ± 0.36). DISCUSSION: Mobilization regimen has significant impact on pre-collection CD34 count. Apheresis facilities may change mobilizing drugs accordingly to achieve a specific HPC goal.

An unexpected paradox: wall shear stress in the aorta is less in patients with severe atherosclerosis regardless of obesity.

BACKGROUND: Obesity is a widespread condition that is more prevalent in Western countries compared to others. Aortic atherosclerosis (AA) is a condition that frequently has been associated with obesity. An obesity paradox, where morbidly obese decedents had either no or minimal AA compared to nonobese decedents, recently has been described by some of us. The explanation for this almost counterintuitive paradox has yet to be determined, but a number of hypotheses were advanced, including hemodynamic factors producing aortic wall shear stress (WSS). The purpose of the present study was to determine if there was a relationship between AA and WSS, as determined by postmortem measurement of aortic wall diameters. METHODS: Circumferences of the aorta at the levels of the ascending, thoracic and abdominal aorta were measured in 274 consecutive autopsies over 2-year period of time. AA was assessed using a previously described grading scale as either mild or severe. Circumferences were mathematically converted to diameters and WSS was calculated using the Hagen-Poiseuille formula. Two different methods to estimate cardiac output were used, both based on literature methods, one of which was body mass index (BMI) dependent, and the other BMI independent. Univariate and multivariable analyses of the relationship between WSS, age, BMI, gender, race and severity of AA were performed. RESULTS: Of the 274 decedents, 140 had mild and 134 had moderate to severe AA. BMI <35 was associated with moderate to severe AA. WSS was inversely correlated with AA in all these segments of the aorta in each BMI subgroup with the exception of the ascending aorta for decedents with BMI ≤35 kg/m2. Contrary to what we had hypothesized, WSS was not a determinant of the obesity paradox. However, among all the variables analyzed, a history of hypertension, diabetes mellitus and age were significant factors for developing AA (relative risk [RR] 0.35, P = .039; RR 1.51, P = .0006, RR 1.19, P = .0001, respectively). CONCLUSIONS: Our data demonstrate that WSS was unexpectedly lower in decedents with moderate and severe AA as compared to those with mild AA. This observation, which requires further investigations, was seen in all BMI ranges and was confirmed by 2 methods to calculate WSS.

A Validation Study of Human Epidermal Growth Factor Receptor 2 Immunohistochemistry Digital Imaging Analysis and its Correlation with Human Epidermal Growth Factor Receptor 2 Fluorescence In situ Hybridization Results in Breast Carcinoma.

BACKGROUND: The Visiopharm human epidermal growth factor receptor 2 (HER2) digital imaging analysis (DIA) algorithm assesses digitized HER2 immunohistochemistry (IHC) by measuring cell membrane connectivity. We aimed to validate this algorithm for clinical use by comparing with pathologists' scoring and correlating with HER2 fluorescence in situ hybridization (FISH) results. MATERIALS AND METHODS: The study cohort consisted of 612 consecutive invasive breast carcinoma specimens including 395 biopsies and 217 resections. HER2 IHC slides were scanned using Philips IntelliSite Scanners, and the digital images were analyzed using Visiopharm HER2-CONNECT App to obtain the connectivity values (0-1) and scores (0, 1+, 2+, and 3+). HER2 DIA scores were compared with Pathologists' manual scores, and HER2 connectivity values were correlated with HER2 FISH results. RESULTS: The concordance between HER2 DIA scores and pathologists' scores was 87.3% (534/612). All discordant cases (n = 78) were only one-step discordant (negative to equivocal, equivocal to positive, or vice versa). Five cases (0.8%) showed discordant HER2 IHC DIA and HER2 FISH results, but all these cases had relatively low HER2 copy numbers (between 4 and 6). HER2 IHC connectivity showed significantly better correlation with HER2 copy number than HER2/CEP17 ratio. CONCLUSIONS: HER2 IHC DIA demonstrates excellent concordance with pathologists' scores and accurately discriminates between HER2 FISH positive and negative cases. HER2 IHC connectivity has better correlation with HER2 copy number than HER2/CEP17 ratio, suggesting HER2 copy number may be more important in predicting HER2 protein expression, and response to anti-HER2-targeted therapy.

Quantitative digital imaging analysis of HER2 immunohistochemistry predicts the response to anti-HER2 neoadjuvant chemotherapy in HER2-positive breast carcinoma.

PURPOSE: Patients with HER2-positive breast cancer commonly receive anti-HER2 neoadjuvant chemotherapy and pathologic complete response (pCR) can be achieved in up to half of the patients. HER2 protein expression detected by immunohistochemistry (IHC) can be quantified using digital imaging analysis (DIA) as a value of membranous connectivity. We aimed to investigate the association HER2 IHC DIA quantitative results with response to anti-HER2 neoadjuvant chemotherapy. METHODS: Digitized HER2 IHC whole slide images were analyzed using Visiopharm HER2-CONNECT to obtain quantitative HER2 membranous connectivity from a cohort of 153 HER2+ invasive breast carcinoma cases treated with anti-HER2 neoadjuvant chemotherapy (NAC). HER2 connectivity and other factors including age, histologic grade, ER, PR, and HER2 fluorescence in situ hybridization (FISH) were analyzed for association with the response to anti-HER2 NAC. RESULTS: Eighty-three cases (54.2%) had pCR, while 70 (45.8%) showed residual tumor. Younger age, negative ER/PR, higher HER2 DIA connectivity, higher HER2 FISH ratio and copy number were significantly associated with pCR in univariate analysis. Multivariate analysis demonstrated only age, HER2 DIA connectivity, PR negativity, and HER2 copy number was significantly associated with pCR, whereas HER2 DIA connectivity had the strongest association. CONCLUSIONS: HER2 IHC DIA connectivity is the most important factor predicting pCR to anti-HER2 neoadjuvant chemotherapy in patients with HER2-positive breast cancer.

Lost in Transportation: Calcium Oxalate Crystals in Kidney Biopsy Specimens Fixed in Michel Medium May Disappear.

CONTEXT.­: Calcium oxalate (CaOx) deposits in a kidney biopsy specimen can be seen in acute or chronic kidney injury and in oxalate nephropathy. Although no established cutoff criteria to diagnose oxalate nephropathy versus incidental CaOx deposition in the kidney exist, these conditions require different treatment. We noticed a significant decrease in the number of CaOx deposits in the kidney biopsy cores that were fixed in Michel transport medium (MTM) as compared to their counterparts fixed in formalin. OBJECTIVE.­: To investigate the impact of different fixatives on the number of CaOx deposits in kidney biopsy specimens. DESIGN.­: Retrospective search for kidney biopsies with diagnosis of CaOx deposition was performed in our Renal Pathology Database between January 1, 2015 and October 15, 2018. RESULTS.­: Seventy-six biopsies with an increased number of CaOx deposits were identified. CaOx deposits were counted on slides from the frozen tissue (MTM fixed or fresh frozen) and from the formalin-fixed cores. The density of CaOx deposits was significantly higher in formalin-fixed cores (13.6 ± 10.0/cm) than in MTM-fixed cores (3.2 ± 5.1/cm; P < .001). CaOx density in the kidney biopsy specimens decreased progressively with increased fixation time in MTM. No significant differences in the CaOx density between formalin-fixed and fresh frozen tissue were observed. CONCLUSIONS.­: Our data demonstrate that fixation in MTM may result in a significant reduction in the number of CaOx deposits in a kidney biopsy specimen. This may make the diagnosis difficult, especially in small biopsy specimens with limited tissue in the formalin-fixed paraffin block.