Katharina Kriegsmann

Combined Immunohistochemistry after Mass Spectrometry Imaging for Superior Spatial Information

Tissue slides analyzed by MS imaging (MSI) are stained by H&E (Haematoxylin and Eosin) to identify regions of interest. As it can be difficult to identify specific cells of interest by H&E alone, data analysis may be impaired. Immunohistochemistry (IHC) can highlight cells of interest but single or combined IHC on tissue sections analyzed by MSI have not been performed.

Analysis of the proliferative activity in lung adenocarcinomas with specific driver mutations

In the last decade it became evident that many lung adenocarcinomas (ADC) harbor key genetic alterations such as KRAS, EGFR or BRAF mutations as well as rearrangements of ROS1 or ALK that drive these tumors. In the present study we investigated whether different driver mutations of ADC result in different proliferation rates, which might have clinical impact, including resistance to therapy, recurrence and prognosis. We analyzed the proliferation index (PI) on full slides of surgically resected ADC (nu202f=u202f230) with known genetic aberrations by means of immunohistochemistry and subsequent digital image analysis and correlated the results with clinicopathological variables including overall (OS) and disease free survival (DFS). We did not observe significant differences in OS or DFS regarding the KRAS or EGFR mutational status (Pu202f=u202f0.56). However, KRAS mutated ADC showed an increased PI compared to EGFR mutated ADC, and ADC with ALK translocations (Pu202f<u202f0.01). Subgroup analysis of EGFR mutated ADC showed a higher PI for tumors harboring a mutation in exon 18 and 20, compared to tumors with a mutation in exon 19 or 21. A PI of 11.5% was the best possible prognostic stratificator for OS (Pu202f=u202f0.01 in KRAS mutated and Pu202f<u202f0.01 in EGFR mutated ADC). In conclusion, the PI differs significantly among ADC with distinct driver mutations. This might explain the varying indications for a prognostic relevance of the PI observed in prior studies. Our study provides a basis for the establishment of a reliable and clinically meaningful PI threshold.

Quantification of number of CD38 sites on bone marrow plasma cells in patients with light chain amyloidosis and smoldering multiple myeloma: NUMBER OF CD38 SITES ON BONE MARROW PLASMA CELLS

Recent approaches in multiple myeloma (MM) treatment have targeted CD38. As antigen expression levels on plasma cells (PCs) were demonstrated to affect response to monoclonal antibody (mAb) treatment, a precise characterization of PC phenotype is warranted.

Platelet Count before Peripheral Blood Stem Cell Mobilization Is Associated with the Need for Plerixafor But Not with the Collection Result

Background: A low platelet count before mobilization has recurrently been identified as risk factor for poor mobilization. Methods: To determine the relevance of this finding for peripheral blood stem cell (PBSC) mobilization, including pre-emptive or rescue plerixafor in the case of poor mobilization, we retrospectively analyzed all patients undergoing PBSC collection at our institution between January 2014 and December 2015 (n = 380). Results: In total, 99% of the patients (377/380) successfully collected a minimum of 2 × 106 CD34+ cells/kg body weight sufficient for a single transplant. Rescue or pre-emptive plerixafor was administered to 11% of the patients (42/380). No correlations between the platelet count before mobilization and the number of peripheral blood CD34+ cells or the CD34+ cell collection result were detected in the entire population or the subgroups according to diagnosis (newly diagnosed multiple myeloma, relapsed multiple myeloma, lymphoma, amyloid light-chain amyloidosis, sarcoma, or germ cell tumor). However, patients requiring pre-emptive or rescue plerixafor had a significantly lower platelet count before mobilization (217/nl vs. 245/nl; p = 0.004). Conclusion: With the current state of the art PBSC mobilization strategies, the platelet count before mobilization was not associated with the CD34+ cell collection result but was associated with the need for pre-emptive or rescue application of plerixafor.

Successful collection of peripheral blood stem cells upon VIDE chemomobilization in sarcoma patients

In patients with Ewing sarcoma and some distinct subgroups of soft tissue sarcoma (STS), a quantitatively sufficient autologous peripheral blood stem cell (PBSC) collection for stem cell support might facilitate treatment continuation, dose‐intensification, and high‐dose chemotherapy. Here, we provide a detailed evaluation of PBSC collection upon vincristine, ifosfamide, doxorubicin, and etoposide (VIDE) chemomobilization.

Digital PCR After MALDI Mass Spectrometry Imaging to Combine Proteomic Mapping and Identification of Activating Mutations in Pulmonary Adenocarcinoma

Matrix assisted laser desorption/ionization time‐of‐flight mass spectrometry imaging (MALDI–MSI) is a powerful tool to analyze the spatial distribution of peptides in tissues. Digital PCR (dPCR) is a method to reliably detect genetic mutations. Biopsy material is often limited due to minimally invasive techniques, but information on diagnosis, prognosis, and prediction is required for subsequent clinical decision making. Thus, saving tissue material during diagnostic workup is highly warranted for best patient care. The possibility to combine proteomic analysis by MALDI–MSI and mutational analysis by dPCR from the same tissue section is evaluated.

In MALDI–Mass Spectrometry Imaging on Formalin‐Fixed Paraffin‐Embedded Tissue Specimen Section Thickness Significantly Influences m/z Peak Intensity

In matrix‐assisted laser desorption/ionization–mass spectrometry imaging (MALDI–MSI) standardized sample preparation is important to obtain reliable results. Herein, the impact of section thickness in formalin‐fixed paraffin embedded (FFPE) tissue microarrays (TMA) on spectral intensities is investigated.

The prognostic and predictive value of IKZF1 and IKZF3 expression in T-cells in patients with multiple myeloma

ABSTRACT Purpose: While recent studies described the role of IKZF1/3 proteins in multiple myeloma (MM) cells, few have highlighted the significance of IKZF1/3 expression in T-cells. In this study we examine the prognostic and predictive value of IKZF1/3 expression in T-cells in patients with MM stage III. Experimental design: We analysed the IKZF1/3 expression levels in T-cells from 45 MM stage I (MMI) and 50 newly diagnosed MM stage III (MMIII) patients, according to Durie-Salmon staging system, by flow cytometry to examine their prognostic and predictive value. We also combined in vivo observations with in vitro assays to determine the effect of IKZF1/3 expression on the T-cell immunophenotype and anti-tumour T-cell response in 162 MMIII patients. Results: We found that high IKZF3, but not IKZF1, expression in T-cells correlates with superior overall survival in MMIII patients treated with immunomodulatory drugs (thalidomide, lenalidomide and pomalidomide). Moreover, we show that higher IKZF3 expression in T-cells inhibits myeloma-specific T-cell response in vitro and that the immunophenotype of patients with high IKZF3 expression shows features that are contrary to the changes induced by immunomodulatory drugs. Although we observed higher IKZF3 expression levels in T-cells from patients with MMIII compared to MMI, IKZF3 expression was unaffected by the tumour microenvironment. Conclusion: In conclusion, IKZF3 expression in T-cells is a predictive value for clinical outcome in MMIII patients treated with immunomodulatory drugs due to its profound modulation of T-cell functionality.

Acalabrutinib, A Second-Generation Bruton’s Tyrosine Kinase Inhibitor

The Brutons tyrosine kinase (BTK) is an essential in the B-cell receptor (BCR) signaling pathway which was identified as crucial in the pathogenesis of B-cell malignancies. Ibrutinib, a first-in-class BTK inhibitor, has been approved for the treatment of distinct B-cell malignancies. To overcome off-target side effects of and emerging resistances to ibrutinib, more selective second-generation BTK inhibitors were developed. Acalabrutinib is a novel second-generation BTK inhibitor and has shown promising safety and efficacy profiles in phase 1/2 clinical trials in patients with relapsed CLL and pretreated MCL. Recently, acalabrutinib was approved by the FDA for treatment of adult patients with MCL who received at least one prior therapy. However, clinical trials on a direct comparison between ibrutinib and acalabrutinib and on combination treatment options with other agents as CD20 antibodies are warranted.

Concurrent Neuroendocrine Carcinoma of the Skin (Merkel Cell Carcinoma) and Squamous Cell Carcinoma of the Skin on the Right Ear Helix

An 86-year-old male was admitted to our department of otorhinolaryngology for partial right ear helix resection due to 2 ulcerated tumors. Gross examination revealed a part of an ear helix measuring 5.0 × 4.0 × 1.5 cm with a 2.0 × 2.0 cm brown-red ulceration on the anterior side and a 0.7 × 0.6 cm brown ulcerated polypoid tumor on the opposite side of the helix (Figure 1). Microscopically, the larger tumor was composed of monomorphic, compact, small, and round cells with scant basophilic cytoplasm, granular chromatin, and brisk mitotic activity. Focal infiltration of lymphatic vessels was observed. The second elevated tumor also showed superficial ulceration besides focal keratinization and consisted of large polygonal cells with eosinophilic cytoplasm and large pleomorphic nuclei with prominent nucleoli. The surrounding skin showed severe basophilic degeneration of the dermal collagen indicative of solar elastosis. Immunohistological evaluation demonstrated CK5/6, CK20, and synaptophysin positivity in the first tumor and positivity for CK5/6 and p40 in the second tumor. The proliferation fraction of the first neoplasm was higher than 90% as indicated by Ki-67 positive tumor cell nuclei. Thus, concurrent Merkel cell carcinoma and squamous cell carcinoma of the skin was diagnosed. Merkel cell carcinoma is a rather rare neoplasm that predominantly affects older adults with light skin types and was first described in 1972. Risk factors include infection with Merkel cell polyomavirus, ultraviolet radiation exposure, and immunosuppression. While an association with other sun-induced malignant tumors such as squamous cell carcinoma, basal cell carcinoma, malignant melanoma, or Bowen’s disease is well recognized, most reported cases developed metachronic. 767325 IJSXXX10.1177/1066896918767325International Journal of Surgical PathologyFischer et al research-article2018