Laurent Castillo

Usefulness of frozen section in rhinocerebral mucormycosis diagnosis and management

Aims: Rhinocerebral mucormycosis (RCM) is a well‐described fulminant fungal infection that presents acutely in patients with ketoacidosis and immunosuppression. Very early diagnosis, established with the demonstration of characterised hyphae in tissues, greatly improves the prognosis of RCM. In this regard, the specificity and the sensitivity of frozen section for the diagnosis and the surgical debridement of RCM were evaluated in this study. Methods and results: Frozen section was performed for the diagnosis (six of seven cases) and surgical treatment (three of seven cases) of RCM. In all cases, diagnosis was made by frozen section and confirmed by histological examination. Frozen section allowed radical surgical excision of infected tissue. In all cases, invasive, broad‐based non‐septated hyphae with branching at right angles were well demonstrated on toluidine blue staining. Cultures were positive for Rhizopus oryzae in three of seven cases. Outcome was favourable for five of seven patients and two patients died after the diagnosis. Conclusions: Frozen section is a specific and sensitive method to make both a quick initial diagnosis of RCM and to successfully eradicate the tissue infected by organisms belonging to the order Mucorales.

The value of polymerase chain reaction detection of Mycobacterium tuberculosis in granulomas isolated by laser capture microdissection

Aims: The aim of this study was to investigate the usefulness of polymerase chain reaction (PCR) detection of Mycobacterium tuberculosis in granulomas isolated by laser capture microdissection (LCM). Methods: The PCR DNA amplification method was used to detect M. tuberculosis in granulomas microdissected from one section stained by haematoxylin and eosin (H&E) from a formalin‐fixed paraffin‐embedded specimen. The results were compared to those obtained from PCR performed from 10 whole paraffin sections of 5 µm each, and with the histology, culture and the patients clinical findings. Results: Forty‐nine formalin‐fixed and paraffin‐embedded samples from 49 patients with a histological suspicion of a mycobacterial infection were investigated. Using culture as the reference method, the sensitivity for the detection of M. tuberculosis was 92% and the specificity was 100% using PCR from microdissected granulomas and were similar to those obtained by using PCR from 10 whole sections. Conclusions: The PCR method of examination of microdissected granulomas from deparaffinised sections is a sensitive, specific and rapid method for the detection of M. tuberculosis in formalin‐fixed and paraffin‐embedded samples. The method is as sensitive as that using PCR on 10 whole tissue sections, thus making it suitable for small biopsies. However, although these methods reduce the delay in diagnosis, culture remains the gold standard for identification of mycobacteria in tissue. Culture also allows for the testing of antibiotic sensitivity of any isolated species, in this way determining appropriate treatment.

Distinct epithelial gene expression phenotypes in childhood respiratory allergy.

Epithelial cell contribution to the natural history of childhood allergic respiratory disease remains poorly understood. Our aims were to identify epithelial pathways that are dysregulated in different phenotypes of respiratory allergy. We established gene expression signatures of nasal brushings from children with dust mite-allergic rhinitis, associated or not associated with controlled or uncontrolled asthma. Supervised learning and unsupervised clustering were used to predict the different subgroups of patients and define altered signalling pathways. These profiles were compared with those of primary cultures of human nasal epithelial cells stimulated with either interleukin (IL)-4, IL-13, interferon (IFN)-&agr;, IFN-&bgr; or IFN-&ggr;, or during in vitro differentiation. A supervised method discriminated children with allergic rhinitis from healthy controls (prediction accuracy 91%), based on 61 transcripts, including 21 T-helper cell (Th) type 2-responsive genes. This method was then applied to predict children with controlled or uncontrolled asthma (prediction accuracy 75%), based on 41 transcripts: nine of them, which were down-regulated in uncontrolled asthma, are directly linked to IFN. This group also included GSDML, which is genetically associated with asthma. Our data revealed a Th2-driven epithelial phenotype common to all children with dust mite allergic rhinitis. It highlights the influence of epithelially expressed molecules on the control of asthma, in association with atopy and impaired viral response.

The Role of Radiation Therapy in Pediatric Mucoepidermoid Carcinomas of the Salivary Glands

OBJECTIVE To investigate the role of radiation therapy in rare salivary gland pediatric mucoepidermoid carcinoma (MEC). STUDY DESIGN A French multicenter retrospective study (level of evidence 4) of children/adolescents treated for MEC between 1980 and 2010 was conducted. RESULTS Median age of the 38 patients was 14 years. Parotid subsite, low-grade, and early primary stage tumors were encountered in 81%, 82%, and 68% of cases, respectively. All except 1 patient were treated by tumoral surgical excision, and 53% by neck dissection (80% of high grades). Postoperative radiation therapy and chemotherapy were performed in 29% and 11% of cases. With a median 62-month follow-up, overall survival and local control rates were 95% and 84%, respectively. There was 1 nodal relapse. Lower grade and early stage tumors had better survival. Postoperative radiation therapy and chemotherapy were associated with similar local rates. Patients with or without prior cancer had similar outcomes. CONCLUSIONS Pediatric salivary gland MEC carries a good prognosis. Low-intermediate grade, early-stage tumors should be treated with surgery alone. Neck dissection should be performed in high-grade tumors. Radiation therapy should be proposed for high grade and/or advanced primary stage MEC. For high-grade tumors without massive neck involvement, irradiation volumes may be limited to the primary area, given the risk of long-term side effects of radiation therapy in children. Pediatric MEC as second cancers retain a similar prognosis. Long-term follow-up is needed to assess late side effects and second cancers.

Thyroid surgery and recurrent laryngeal nerve monitoring

UNLABELLED Recurrent laryngeal nerve paralysis is a much-dreaded complication of thyroid surgery. OBJECTIVE To study the feasibility and the reliability of a recurrent laryngeal nerve monitoring technique. MATERIALS AND METHODS This was a prospective study including 36 patients proposed for thyroid surgery with recurrent laryngeal nerve monitoring. They underwent post-operative fibre-optic laryngeal examination and speech therapist consultation. RESULTS Our technique of nerve monitoring showed a 98 per cent sensitivity and 86 per cent specificity. CONCLUSIONS Recurrent laryngeal nerve monitoring is a feasible and reliable technique. It can be used to avoid bilateral nerve injury and to increase the surgeons confidence but not to replace a systematic nerve identification and a careful dissection.

DENTALMAPS: Automatic Dental Delineation for Radiotherapy Planning in Head and Neck Cancer

PURPOSE To propose an automatic atlas-based segmentation framework of the dental structures, called Dentalmaps, and to assess its accuracy and relevance to guide dental care in the context of intensity-modulated radiotherapy. METHODS AND MATERIALS A multi-atlas-based segmentation, less sensitive to artifacts than previously published head-and-neck segmentation methods, was used. The manual segmentations of a 21-patient database were first deformed onto the query using nonlinear registrations with the training images and then fused to estimate the consensus segmentation of the query. RESULTS The framework was evaluated with a leave-one-out protocol. The maximum doses estimated using manual contours were considered as ground truth and compared with the maximum doses estimated using automatic contours. The dose estimation error was within 2-Gy accuracy in 75% of cases (with a median of 0.9 Gy), whereas it was within 2-Gy accuracy in 30% of cases only with the visual estimation method without any contour, which is the routine practice procedure. CONCLUSIONS Dose estimates using this framework were more accurate than visual estimates without dental contour. Dentalmaps represents a useful documentation and communication tool between radiation oncologists and dentists in routine practice. Prospective multicenter assessment is underway on patients extrinsic to the database.

Necrotizing otitis externa: a systematic review.

Objective To carry out a systematic review of scientific evidence available about necrotizing otitis externa, emphasizing epidemiologic data, diagnosis criteria, treatment protocols, follow-up criteria, prognosis factors, and chronologic evolution. Data Sources PubMed/MEDLINE and the Cochrane Database of Systematic Reviews were searched for publications in English and French languages, between 1968 and October 1, 2011. Study Selection We included publications of all types including at least 6 cases. We excluded publications focused on cranial base osteomyelitis not originating from the external ear and publications limited to a specific population. Data Extraction We assessed publication quality according to international guidelines. Data Synthesis For each publication, data were entered in a spreadsheet software for analysis. We excluded individual data already published in other studies or reviews. Conclusion Our review revealed the absence of strong scientific evidence regarding diagnosis criteria, treatment protocols and follow-up criteria. This implies the use of highly empirical indexes of suspicion in clinical practice. Our review confirmed the existence of a typical but not exclusive population at risk (aged, male, and diabetic patient) and also revealed major issues: lack of primary prevention in population at risk, delays before referral and management, bacteriologic issues caused by antibiotic misuse (agent identification problems, rise of resistant strains), persistence of recurrent cases. A better diffusion of medical information should help improve the management of this severe disease.

Cochlear implantation surgery without posterior tympanotomy: Can we still improve it?

Conclusion: The amendments made to pre-existing transcanal approaches limit the possibility of extrusion of the electrode and reduce the time of ‘blind’ surgery. Objective: Alternative techniques to classic mastoidectomy and posterior tympanotomy for cochlear implantation have already been described but their main drawbacks result in either: (i) the risk of an electrode extrusion through the skin as the groove is drilled into the auditory canal or (ii) the risk of a facial nerve injury as the tunnel is drilled blindly into the posterior canal wall. The aim of this study was to describe and evaluate a new transcanal approach for cochlear implantation ruling out these difficulties. Patients and methods: Through a minimal retroauricular skin incision, a cochleostomy is performed directly via the auditory canal. The passage for the electrode is performed after drilling both a suprameatal hollow and a 1.5 mm hole into the superior-posterior canal wall, which opens the facial recess by an anterior approach. Thanks to this hole a transwall tunnel can afterwards be dug safely. Results: Twenty-three patients (8 adults, 15 children) were implanted without any difficulty. The mean follow-up was 22 months. No postoperative complication was observed.

Longterm Survival in Acute Rhinocerebral Mucormycosis with Giant Cell Arteritis and Foreign Body Granulomas

A case of rhinocerebral mucormycosis occurring in a 41-year-old man with insulin-treated diabetes mellitus is reported. Microscopically, biopsy samples obtained from the left ethmoid and middle turbinate sinuses contained fungi that formed mycotic granulomas associated with multinucleate giant cell arteritis. The multinucleate giant cells contained broad, infrequently septate hyphase consistent with mucormycosis. The patient received surgical debridement with extenteration of the left orbit, and intravenous liposome-encapsulated amphotericin B. After 12 months, examination of the patient revealed complete healing. Multinucleate giant cell granulomas and arteritis are only exceptionally associated with rhinocerebral mucormycosis, but these histologic findings may be correlated with a progressive disease with better prognosis.

Setting up a Prospective Thyroid Biobank for Translational Research: Practical Approach of a Single Institution (2004–2009, Pasteur Hospital, Nice, France)

In the last few years, conditions for setting up a human biobank in France have been upgraded by taking into account (1) the new laws and regulations that integrate the ethical and societal dimension of biobanking and delineate the risks for patients associated with the procurement of human cells and tissues, (2) the increasing request by scientists for human samples with proven biological quality and sophisticated sets of annotations, including information produced through the evergrowing use of molecular biology in pathology, and (3) establishment of procedures concerning the safety of the personnel working with biological products. For this purpose, health authorities and national research institutes in France have provided significant support for the set up of biobanks. The present work was conducted to describe how we set up a biobank targeting diseases of a specific organ (thyroid gland), with the aim of rapidly developing translational research projects. The prospective experience of a single institution (Pasteur Hospital, Nice, France) over a 6-year period (2004-2009) is presented from the practical point of view of a surgical pathology laboratory. We describe different procedures required to obtain high-quality thyroid biological resources and clinical annotations. The procedures were established for the management of biological products obtained from 1454 patients who underwent thyroid surgery. The preanalytical steps leading to the storage of frozen specimens were carried out in parallel with diagnostic procedures. As the number of international networks for research programs using biological products is steadily increasing, it is crucial to harmonize the procedures used by biobanks. In this regard, the described thyroid biobank has been set up using criteria established by the French National Cancer Institute (Institut National du Cancer) to guarantee the quality of different collections stored in biobanks.