Christian von Buchwald

Evolution and diversification of Pseudomonas aeruginosa in the paranasal sinuses of cystic fibrosis children have implications for chronic lung infection

The opportunistic pathogen Pseudomonas aeruginosa is a frequent colonizer of the airways of patients suffering from cystic fibrosis (CF). Depending on early treatment regimens, the colonization will, with high probability, develop into chronic infections sooner or later, and it is important to establish under which conditions the switch to chronic infection takes place. In association with a recently established sinus surgery treatment program for CF patients at the Copenhagen CF Center, colonization of the paranasal sinuses with P. aeruginosa has been investigated, paralleled by sampling of sputum from the same patients. On the basis of genotyping and phenotypic characterization including transcription profiling, the diversity of the P. aeruginosa populations in the sinuses and the lower airways was investigated and compared. The observations made from several children show that the paranasal sinuses constitute an important niche for the colonizing bacteria in many patients. The paranasal sinuses often harbor distinct bacterial subpopulations, and in the early colonization phases there seems to be a migration from the sinuses to the lower airways, suggesting that independent adaptation and evolution take place in the sinuses. Importantly, before the onset of chronic lung infection, lineages with mutations conferring a large fitness benefit in CF airways such as mucA and lasR as well as small colony variants and antibiotic-resistant clones are part of the sinus populations. Thus, the paranasal sinuses potentially constitute a protected niche of adapted clones of P. aeruginosa, which can intermittently seed the lungs and pave the way for subsequent chronic lung infections.

The role of miRNAs in human papilloma virus (HPV)-associated cancers: bridging between HPV-related head and neck cancer and cervical cancer

Background:Although the role of human papilloma virus (HPV) in cervical squamous cell carcinoma (CSCC) is well established, the role in head and neck SCC (HNSCC) is less clear. MicroRNAs (miRNAs) have a role in the cancer development, and HPV status may affect the miRNA expression pattern in HNSCC. To explore the influence of HPV in HNSCC, we made a comparative miRNA profile of HPV-positive (HPV+) and HPV-negative (HPV−) HNSCC against CSCC.Methods:Fresh frozen and laser microdissected-paraffin-embedded samples obtained from patients with HPV+/HPV− HNSCC, CSCC and controls were used for microarray analysis. Differentially expressed miRNAs in the HPV+ and HPV− HNSCC samples were compared with the differentially expressed miRNAs in the CSCC samples.Results:Human papilloma virus positive (+) HNSCC had a distinct miRNA profile compared with HPV− HNSCC. Significantly more similarity was seen between HPV+ HNSCC and CSCC than HPV− and CSCC. A set of HPV core miRNAs were identified. Of these especially the miR-15a/miR-16/miR195/miR-497 family, miR-143/miR-145 and the miR-106-363 cluster appear to be important within the known HPV pathogenesis.Conclusion:This study adds new knowledge to the known pathogenic pathways of HPV and substantiates the oncogenic role of HPV in subsets of HNSCCs.

The role of human papillomavirus in head and neck cancer

Lajer CB, von Buchwald C. The role of human papillomavirus in head and neck cancer. APMIS 2010; 118: 510–519.

Implication of 18F‐Fluoro‐2‐Deoxy‐D‐Glucose Positron Emission Tomography on Management of Carcinoma of Unknown Primary in the Head and Neck: A Danish Cohort Study

Objectives To demonstrate the efficacy of whole‐body 18F‐fluoro‐2‐deoxy‐D‐glucose positron emission tomography (18F‐FDG PET) in the detection of a carcinoma of unknown primary after conventional diagnostic workup in patients with a metastatic neck lesion and to demonstrate how the treatment policy of wide‐field irradiation can be safely modified in relation to the findings from PET scanning.

Risks of malignancy in inverted papilloma of the nose and paranasal sinuses.

Purpose of reviewThe majority of inverted nasal papilloma are benign and treatment is by complete local surgical removal. There is an associated real, but small risk of malignancy, which may coexist at the time of presentation or develop at a later time. This article reviews some of the recent publications addressing the association of inverted papilloma with malignancy. Recent findingsNeither the etiology of inverted papilloma nor the factors responsible for malignant transformation are fully elucidated to date. Inverted papilloma is associated with squamous cell carcinoma in approximately 10% of the cases. Malignancy may occur synchronously or metachronously. SummaryBased on the literature, the rates of synchronous and metachronous carcinoma are 7.1 and 3.6%, respectively, although rates may be exaggerated due to a referral bias to tertiary centres. A thorough removal of all diseased mucosa is curative and a meticulous histological examination of the entire specimen is necessary. The working risk is approximately 10%. Recurrent disease and metachronous carcinoma can develop after a prolonged period of time. As most recurrences are due to incomplete resection, it is mandatory to perform a close follow-up, with biopsies performed when indicated. Life-long follow-up is recommended.

Human papillomavirus in conjunctival papilloma.

AIM To examine conjunctival papillomas for the presence of human papillomavirus (HPV) and koilocytosis. METHODS Archival paraffin embedded tissue from 55 conjunctival papillomas was analysed for the presence of HPV by polymerase chain reaction and subsequent filter hybridisation. Histological sections of the 55 papillomas were evaluated for the presence of koilocytosis. RESULTS HPV was present in 48 of 52 (92%) β globin positive papillomas. HPV type 6/11 were found in 40 of 47 investigated papillomas and a double infection with HPV 6/11 and 16 was identified in a single papilloma. In six papillomas the HPV type could not be identified. Koilocytosis was present in 22 of 55 papillomas (40%). CONCLUSION There is a strong association between HPV and conjunctival papillomas. HPV type 6/11 is the most common HPV type in conjunctival papilloma. The sensitivity of koilocytosis as an indicator of HPV in conjunctival papilloma is low.

A high and increasing HPV prevalence in tonsillar cancers in Eastern Denmark, 2000-2010: the largest registry-based study to date.

The aim was to explore whether the incidence of tonsillar squamous cell carcinomas (TSCCs) increased in Eastern Denmark, 2000–2010, and whether human papillomavirus (HPV) could explain the increase, and to assess the association of HPV prevalence with gender, age, and origin (i.e., the certainty of tonsillar tumor origin). We applied HPV DNA PCR and p16 immunohistochemistry to all TSCCs registered in the Danish Head and Neck Cancer Group (DAHANCA) and in the Danish Pathology Data Bank (n = 632). Pathologists reviewed and subdivided the tumors into two groups: specified and nonspecified TSCCs. Approximately 10% of HPV‐positive tumors was genotyped by amplicon next‐generation sequencing. The overall crude incidence of TSCCs increased significantly (2.7% per year) and was explained by an increasing incidence of HPV‐positive TSCCs (4.9% per year). The overall HPV prevalence was 58%, with HPV16 being the predominant HPV type. In multivariate analysis, the HPV prevalence was associated with age (<55 vs. >60 years) (OR, 1.72; 95% CI 1.13–2.63) and origin (nonspecified vs. specified TSCCs) (OR, 0.15; 95% CI 0.11–0.22). The association of HPV prevalence with origin increased over time in specified TSCCs (OR per year, 1.10; 95% CI 1.01–1.19), whereas no change over time was observed among nonspecified TSCCs (OR per year, 0.99; 95% CI 0.90–1.08). In conclusion, the observed increase in the number of HPV‐positive TSCCs can explain the increasing number of TSCCs in Eastern Denmark, 2000–2010. HPV prevalence was associated with younger age (<55 years) and a high certainty of tonsillar tumor origin.

Colonisation and infection of the paranasal sinuses in cystic fibrosis patients is accompanied by a reduced PMN response

BACKGROUND We studied whether the sinuses might be foci for Pseudomonas aeruginosa lung infection. METHODS Endoscopic Sinus Surgery was performed in 78 CF patients; PFGE was used for bacterial genotyping. Material from sinuses and lungs were Gram-stained to detect biofilms. Immunoglobulins were measured in serum and saliva. RESULTS When P. aeruginosa was cultured simultaneously from the sinuses and the lungs they were genetically identical in 38 of the 40 patients (95%). In the sinuses, P. aeruginosa formed biofilms with minimal cellular inflammation, probably because of a significantly higher local production of secretory IgA compared with IgG (p<0.001). CONCLUSIONS We have shown that P. aeruginosa form biofilm in the sinuses, which constitute an important bacterial reservoir for subsequent lung infection. The high amount of IgA in the upper airways probably protects P. aeruginosa from the inflammatory immune system, and they can proceed unnoticed into a permanent infectious focus that cannot be eradicated with antibiotics.

Esthesioneuroblastoma: a Danish demographic study of 40 patients registered between 1978 and 2000

Objective A retrospective review of all diagnosed cases of esthesioneuroblastoma registered in Denmark between 1978 and 2000 was carried out in order to obtain epidemiological data and optimize national treatment guidelines. Material and Methods Forty cases were verified histologically and included in the analysis Epidemiological and histopathological data were evaluated in relation to the clinical outcome. Results The 40 cases represent an incidence rate of 0.4 cases/million inhabitants per year. Eight (20%) patients were classified as Kadish stage A, 13 (32.5%) as stage B and 19 (47.5%) as stage C. The histopathological findings were classified according to the grading system of Hyams The median follow-up time was 2.3 years (range 0.3–11.1 years). The 5-year crude survival rate was 61%, with a median survival of 3.1 years (range 0.3–19.2 years). The 5-year disease-free survival rate was 50%, with a median survival of 1.7 years (range 0–19.2 years). Only 3 (7%) patients had positive cervical lymph nodes at presentation. A nationwide consensus regarding treatment was seen in patients classified as Kadish stages A and B. The longest duration before the first recurrence of esthesioneuroblastoma was 5(½) years. Conclusion The following therapeutic guidelines are suggested: Kadish stage A patients, surgical tumour resection and radiotherapy; Kadish stage B, surgical tumour resection and radiotherapy; Kadish stage C, surgical tumour resection via a craniofacial resection and radiotherapy combined with chemotherapy. Long-term follow-up of esthesioneuroblastoma patients is mandatory.

The role of SPECT-CT in the lymphoscintigraphic identification of sentinel nodes in patients with oral cancer

Conclusion: SPECT-CT may improve the localization of sentinel nodes (SNs) in patients with oral squamous cell carcinoma (OSCC). Compared with planar lymphoscintigraphy SPECT-CT detected more SNs and provided additional anatomical and spatial information about their localization. New generation SPECT with higher resolution CT scanners are expected to provide more accurate information about the localization of SNs. Objective: To assess the role of combined SPECT-CT in SN identification in the clinically negative neck of patients with OSCC. Materials and methods: Lymphoscintigraphy comprising planar and SPECT-CT acquisition was performed in 34 consecutive patients with OSCC stage I and II (T1-2N0M0) prior to sentinel node biopsy (SNB) and selective neck dissection. The number of SNs and anatomical location was recorded according to lymphoscintigraphy and operative findings. Results: SNB was conducted in 33 patients. SNs were identified in 94% (32/34) of the patients using SPECT-CT. In 91% (29/32) of the patients SNs were harvested from all of the levels involved on SPECT-CT. SPECT-CT imaging demonstrated extra SNs compared with planar lymphoscintigraphic imaging in 47% (15/32) of patients. In seven cases the anatomical level of SN according to SPECT-CT was reclassified during surgery. The overall incidence of lymph node metastases was 19% (6/32). There were no false negative SNs.