Preclinical Head and Neck Squamous Cell Carcinoma Models for Combined Targeted Therapy Approaches.

This study aimed to refine combined targeted approaches on well-characterized, low-passage tumor models. Upon in vivo xenografting in immunodeficient mice, three cell lines from locally advanced or metastatic HNSCC were established. Following quality control and basic characterization, drug response was examined after therapy with 5-FU, Cisplatin, and cyclin-dependent kinase inhibitors (abemaciclib, THZ1). Our cell lines showed different in vitro growth kinetics, morphology, invasive potential, and radiosensitivity. All cell lines were sensitive to 5-FU, Cisplatin, and THZ1. One cell line (HNSCC48 P0 M1) was sensitive to abemaciclib. Here, Cyto-FISH revealed a partial CDKN2a deletion, which resulted from a R58* mutation. Moreover, this cell line demonstrated chromosome 12 polysomy, accompanied by an increase in CDK4-specific copy numbers. In HNSCC16 P1 M1, we likewise identified polysomy-associated CDK4-gains. Although not sensitive to abemaciclib per se, the cell line showed a G1-arrest, an increased number of acidic organelles, and a swollen structure. Notably, intrinsic resistance was conquered by Cisplatin because of cMYC and IDO-1 downregulation. Additionally, this Cisplatin-CDKI combination induced HLA-ABC and PD-L1 upregulation, which may enhance immunogenicity. Performing functional and molecular analysis on patient-individual HNSCC-models, we identified CDK4-gains as a biomarker for abemaciclib response prediction and describe an approach to conquer intrinsic CDKI resistance.

Establishment and characterization of patient-derived head and neck cancer models from surgical specimens and endoscopic biopsies.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is heterogeneous in etiology, phenotype and biology. Patient-derived xenografts (PDX) maintain morphology and molecular profiling of the original tumors and have become a standard "Avatar" model for human cancer research. However, restricted availability of tumor samples hindered the widespread use of PDX. Most PDX-projects include only surgical specimens because reliable engraftment from biopsies is missing. Therefore, sample collection is limited and excludes recurrent and metastatic, non-resectable cancer from preclinical models as well as future personalized medicine. METHODS: This study compares the PDX-take rate, -growth, histopathology, and molecular characteristics of endoscopic specimens with surgical specimens. HNSCC samples (n = 55) were collected ad hoc, fresh frozen and implanted into NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ mice. RESULTS: Engraftment was successful in both sample types. However, engraftment rate was lower (21 vs. 52%) and growth delayed (11.2 vs. 6.7 weeks) for endoscopic biopsies. Following engraftment, growth kinetic was similar. Comparisons of primary tumors and corresponding PDX models confirmed preservation of histomorphology (HE histology) and molecular profile (Illumina Cancer Hotspot Panel) of the patients' tumors. Accompanying flow cytometry on primary tumor specimens revealed a heterogeneous tumor microenvironment among individual cases and identified M2-like macrophages as positive predictors for engraftment. Vice versa, a high PD-L1 expression (combined positive score on tumor/immune cells) predicted PDX rejection. CONCLUSION: Including biopsy samples from locally advanced or metastatic lesions from patients with non-surgical treatment strategies, increases the availability of PDX for basic and translational research. This facilitates (pre-) clinical studies for individual response prediction based on immunological biomarkers.

EGFR and BRAF mutations in inverted sinonasal papilloma - a more complex landscape?

Inverted (Schneiderian) sinonasal papilloma (ISP) is a neoplasm derived from mucosa of the sinonasal tract characterized by local aggressive growth, a tendency to recur and an association with sinonasal carcinoma. The etiology of ISP remains unclear. Recently, identical mutations in exons 19 and 20 of the oncogene EGFR were reported in ISP and ISP-associated sinonasal carcinoma. Nevertheless, it remains unclear whether recurring ISPs show identical EGFR mutations at different time points or whether these mutations are identical throughout the respective ISP sample. We used Sanger sequencing to test 60 formalin-fixed paraffin embedded ISP samples from 40 patients regarding mutations in exons 19 and 20 of EGFR-together with exon 15 of BRAF. Overall, 32 samples of 22 patients showed a mutation in EGFR exon 20, whereas 28 samples of 18 patients showed none. No mutation in EGFR exon 19 was found in any sample. Four samples of four patients showed a BRAF exon 15 mutation. Interestingly, samples of four patients exhibited genetic heterogeneity, enabling us to report this in ISP for the first time.

Open Mastoid Cavity Obliteration With a High-Porosity Hydroxyapatite Ceramic Leads to High Rate of Revision Surgery and Insufficient Cavity Obliteration.

OBJECTIVE: To assess long-term results and present experience with a high-porosity hydroxyapatite ceramic for obliterating large open mastoid cavities. STUDY-DESIGN: Cross-sectional cohort study. SETTING: Tertiary academic referral center. PATIENTS: All patients who underwent tympanomastoid surgery for chronic middle ear disease or revision surgery with reduction of an open mastoid cavity using a highly porous hydroxyapatite matrix material (HMM) between May 2005 and June 2013 were assessed for eligibility. Twenty three patients (56.9 ±â€Š18.3 yr) were included. INTERVENTION: Primary middle ear surgery or revision surgery using a HMM. MAIN OUTCOME MEASURES: Pure-tone average, computed tomography (CT), and magnetic resonance imaging (MRI) to investigate osseoinduction, osseointegration and presence of cholesteatoma, current quality of life assessed by Zurich Chronic Middle Ear Inventory and change in quality of life post-intervention assessed by the Glasgow Benefit Inventory. RESULTS: Patients were reexamined after a mean follow-up period of 88.3 months (SD 21.4 mo) after obliteration of the open mastoid cavity with HMM. Compared with visit 1, patients showed a significantly reduced ABG at visit 2 (29.22 dB ±â€Š2.71 dB versus 12.77 dB ±â€Š3.46 dB).CT scan was carried out in 21 patients (91%) patients and 17 patients (74%) underwent MRI.Revision surgery was required in a total of 17 cases (74%). In four patients recurrent cholesteatoma was found at follow up. CONCLUSIONS: Poor cavity obliteration, a high rate of revision surgery and difficult differentiation between recurrent cholesteatoma and granulation tissue in CT scan was observed.

[Papillary cystadenoma: a rare differential diagnosis of a paratesticular tumour]. / Papilläres Zystadenom als seltene Differenzialdiagnose einer paratestikulären Raumforderung.

Testicular and paratesticular cystadenomas arise from an oviduct-like structure, which, morphologically, is almost identical with the ovarian surface epithelium. These are very rare benign tumours of adults. They present as asymptomatic cystic lesions. Bilateral paratesticular cystadenomas are associated with the Von-Hippel-Lindau syndrome and may be associated with infertility. Most cystadenomas are benign, but a few cases of malignant transformation of embryonic remnants have been reported in the appendix testis, including cases of adenocarcinoma, cystadenocarcinoma, and a Müllerian-type epithelial tumour with a low malignant potential. We report the case of a 74-year-old man with a rare paratesticular cystadenoma of the male adnexa.

Liver-intestine-cadherin is a sensitive marker of intestinal differentiation during Barrett's carcinogenesis.

BACKGROUND: Histopathologic differentiation between the stages of Barrett's carcinogenesis is often challenging. Liver-intestine (LI)-cadherin, an intestine-specific marker, is involved in intestinal metaplasia development in gastric and colon cancers and could be of value in diagnosis and differentiation. AIMS: To examine the expression of LI-cadherin in the sequence of Barrett's carcinogenesis and to evaluate its association with clinicopathological data. METHODS: LI-cadherin expression was immunohistologically investigated, by use of anti-CDH17 antibody, in gastric mucosa (GM) biopsies taken from the cardia (n = 9), in Barrett's esophagus (BE) without intraepithelial neoplasia (without IEN) (n = 9) and BE with low-grade IEN (n = 11), and in esophageal adenocarcinoma (ADC) (n = 13). RESULTS: The immunoreactivity score was highest in adenocarcinoma (mean IRS = 4.0), and dropped gradually from BE with IEN and BE without IEN (mean IRS = 2.0) to cardia mucosa (IRS = 0). Similarly, the intensity of staining and the percentage of positive cells increased during the sequential stages of BE carcinogenesis. Comparative analysis showed that LI-cadherin expression was significantly different between cardiac epithelium and ADC. Also, percentage of positive cells in GM was significantly different from that in BE with IEN. LI-cadherin IRS was lower for tumors with poor differentiation than for moderately differentiated tumors, but the difference was not statistically significant. CONCLUSIONS: LI-cadherin is a sensitive marker of intestinal metaplasia and can be helpful for early histologic diagnosis of Barrett's esophagus; it is, however, not significantly different between BE with and without IEN, and cannot be used to distinguish between these.