PET/MRI and genetic intrapatient heterogeneity in head and neck cancers.

PURPOSE: The relation between functional imaging and intrapatient genetic heterogeneity remains poorly understood. The aim of our study was to investigate spatial sampling and functional imaging by FDG-PET/MRI to describe intrapatient tumour heterogeneity. METHODS: Six patients with oropharyngeal cancer were included in this pilot study. Two tumour samples per patient were taken and sequenced by next-generation sequencing covering 327 genes relevant in head and neck cancer. Corresponding regions were delineated on pretherapeutic FDG-PET/MRI images to extract apparent diffusion coefficients and standardized uptake values. RESULTS: Samples were collected within the primary tumour (n = 3), within the primary tumour and the involved lymph node (n = 2) as well as within two independent primary tumours (n = 1). Genetic heterogeneity of the primary tumours was limited and most driver gene mutations were found ubiquitously. Slightly increasing heterogeneity was found between primary tumours and lymph node metastases. One private predicted driver mutation within a primary tumour and one in a lymph node were found. However, the two independent primary tumours did not show any shared mutations in spite of a clinically suspected field cancerosis. No conclusive correlation between genetic heterogeneity and heterogeneity of PET/MRI-derived parameters was observed. CONCLUSION: Our limited data suggest that single sampling might be sufficient in some patients with oropharyngeal cancer. However, few driver mutations might be missed and, if feasible, spatial sampling should be considered. In two independent primary tumours, both lesions should be sequenced. Our data with a limited number of patients do not support the concept that multiparametric PET/MRI features are useful to guide biopsies for genetic tumour characterization.

Prognostic factors in oral and oropharyngeal cancer based on ultrastructural analysis and DNA methylation of the tumor and surgical margin.

Oral and oropharyngeal cancers are characterized by relatively low 5- year survival rates due to many factors, including local recurrence. The identification of new molecular markers may serve for the estimation of prognosis and thus augment treatment decisions and affect therapy outcome. The aim of this study was to describe the morphological characteristics and the DNA methylation status of the CDKN2A,CDH1, ATM, FHIT and RAR- genes in the central and peripheral part of the tumor and the surgical margin and evaluate their prognostic significance. 53 patients with oral and oropharyngeal cancer were enrolled to the prospective study, and had been primarily treated surgically. Correlations between morphological data, hypermethylation status and clinicopathological data, as well as prognosis, were assessed. Nuclei polymorphism highly correlated with T stage (p < 0.0001), N stage (p < 0.046), and metastases to the lymph nodes pN (p < 0.004 ). Also, the number of cells in irregular mitosis correlated with T stage (p < 0.004), and highly with pN (p < 0.009). The significance of CDKN2A hypermethylation as a good prognostic factor was also established in the Kaplan-Meir test. The ultrastructural analysis showed that none of the examined tumors had homogenous texture and that resection margin specimens clean in HE stained tissue samples frequently contained single tumor cells or few cells in groups surrounded by connective tissue. This indicates the superiority of electron microscopy over standard histopathological analysis. Thus, a combination of such morphological examination with epigenetic parameters described herein could result in the discovery of promising new prognostic markers of the disease.

Nucleolar organizer regions in squamous cell carcinoma of the head and neck.

Nucleolar organizer regions are collections of nucleolar proteins associated with ribosomal genes that can be visualized in histologic sections using a silver colloid stain, thus the term silver-staining nucleolar organizer region (AgNOR). In some tissues, the number of AgNORs per nucleus correlates with cellular proliferation and, independently, with malignant change. AgNORs were studied in 66 paraffin-embedded head and neck squamous cell carcinomas and in 12 samples of normal tonsillar squamous epithelium. Carcinomas had a significantly higher mean AgNOR count than the benign epithelium (P less than .0001). Among carcinomas, mean AgNOR count increased with stage of the disease (P less than .001), but there was no significant correlation with histologic grade or DNA ploidy as determined by flow cytometry. These data suggest that AgNOR count should be evaluated as a possible aid in differentiating benign from malignant squamous epithelial proliferations in the head and neck, and also possibly as a prognostic marker in these carcinomas.

Integrin expression in head and neck cancers.

Neoplastic transformation results in rearrangement of the cell membrane with a breakdown of the regular expression of adhesion molecules such as integrins. A relationship may exist between the intensity of this alteration, and the form it takes, and a tumour's ability to metastatise. We studied this possibility by investigating the epithelial integrin expression of 35 head and neck squamous cell carcinomas. Two types of positivity were observed: one associated with tumours with a better prognostic index, the other with those characterized by greater malignancy.

Is transposed skin transformed in major head and neck mucosal reconstruction?

We used histological and histochemical methods to investigate the possible changes with time in skin transposed into the oropharynx and oral cavity of patients whose surgical wounds were reconstructed with the classic pectoralis major flap. We found histological evidence that skin morphology was maintained (keratinization with reduced, but the desquamating layer, hair follicles, sweat and sebaceous glands were identifiable), and noted an intense inflammatory reaction in the dermis. Histochemical studies confirmed the progressive flattening of the basal interdigitations between the epithelium and dermis, and the gradual reconstruction of the basement membrane. Although skin-mucosa continuity developed fairly quickly without scar reactions, the two epithelia maintained their original patterns of keratin production, i.e., their textural peculiarities. We propose an original method for the transposition of muscular flaps implanted with autologous culture of keratinocytes, an approach developed in an attempt to ensure more satisfactory rehabilitation of the removed mucosal structures.

[Hemangiopericytoma of parapharyngeal space]. / Emangiopericitoma dello spazio parafaringeo.

The parapharyngeal space is a rare site of parapharyngeal neoplasms: their diagnosis and therapeutic treatment offer peculiar challenges. Parapharyngeal tumours may be primary, metastatic or diffused with regaed continuity. They are mostly benign (mixed, neurogenic, vascular tumours, etc.) rather than malignant neoplasms (adenocystic carcinoma, adenocarcinoma, lymphoma, etc.). In order to diagnosis parapharyngeal tumours differentially it is important to consider very rare type of neoplasms such as hemangiopericytomas. In this paper the Authors describe a case of hemangiopericytoma of the parapharyngeal space indicating the main diagnosis procedures, especially CT scan, Magnetic resonance and angiography. They discuss pathological aspects with particular regard to the differential diagnosis between benign and malignant tumour of this kind as well as prognoses. The Authors also describe surgical treatment in relation to particular parapharyngeal localization.

[Ultrastructure of chemodectomas of the neck]. / Ul'trastruktura khemodektom shei.

Two types of cells (dark and clear) with secretory granules in the cytoplasm were identified in these tumors. No specific ultrastructural features that would distinguish tumors differing in the degree of maturity were noted in the cells.

Evaluation of optical coherence tomography to discriminate lesions of the upper aerodigestive tract.

BACKGROUND: This study evaluated the capability of optical coherence tomography (OCT) to differentiate premalignant and early malignant lesions of the upper aerodigestive tract (UADT). METHODS: An OCT screening was performed in 52 healthy volunteers. Epithelial thicknesses on 38 OCT images and histopathological slides were correlated. One hundred primary lesions were rated via OCT concerning invasiveness by an "unblinded" investigator, then biopsied, and the results correlated. All OCT images were evaluated by 3 "blinded" investigators. Forty-eight images underwent retrospective image analysis. RESULTS: Screening showed large differences concerning epithelial thicknesses, but good correlation (κ = 0.63) between OCT and histopathological slides. In the unblinded evaluation, noninvasive and invasive lesions could be distinguished with a sensitivity of 88.9% and specificity of 89.0% whereas the blinded evaluations led to sensitivities of 100%, 66.7%, and 77.8% and specificities of 75.8%, 71.4%, and 70.3%. The difference of mean intraepithelial intensity reductions in dysplasias (38.7%) and hyperplasias (18.9%) was statistically significant. CONCLUSION: OCT complements visual inspection for differentiating UADT-lesions.

Characterization of sugar receptor expression by neoglycoproteins in oral and oropharyngeal squamous cell carcinomas.

Recognition of the carbohydrate part of cellular glycoconjugates by sugar receptors like lectins may contribute to biosignaling and interactions between normal and transformed cells. Such recognitions may be essential for establishing phenotypic characteristics in neoplastic cells, including metastasis-associated properties. To evaluate various glycoconjugates in tumor diagnosis and clinical therapy, a panel of 18 biotinylated neoglycoproteins was prepared. This included conjugates of a histochemically inert carrier protein and crucial sugar moieties such as D-glucuronic acid, alpha- and beta-N-acetyl-galactosamine, beta-N-acetyl-glucosamine, melibiose, lactose, maltose, cellobiose, mannose, mannose-6-phosphate, fucose, rhamnose, and xylose. In so doing the diazo derivative of the respective p-aminophenyl glycosides was coupled with galactose, beta-N-acetyl-galactosamine or beta-N-acetyl-glucosamine via an epoxy group-containing aliphatic spacer. Other glycoconjugates used were the proteoglycan heparin and the sulfated fucan fucoidan. Labeling was effected with cyanogen bromide activation and aminoalkylation for specific detection of endogeneous sugar receptors, especially lectins. Tissues studied were paraformaldehyde-fixed, paraffin-embedded surgical biopsies from patients with different stages of squamous cell carcinomas (SCCs) of the oral cavity (n = 16) and oropharynx (n = 17), including three lymph node metastases from oropharyngeal primary tumors. Semiquantitative binding differences of probes to tumor stages were evaluated statistically by the Mann-Whitney U-Wilcoxon rank sum W test. Specific binding of a probe to cytoplasmic and nuclear structures was detected with apparent quantitative differences. Overall, the cytoplasmic compartment revealed a higher intensity of histochemical reaction than did nuclear structures, indicating a comparatively higher density of specific carbohydrate receptors.(ABSTRACT TRUNCATED AT 250 WORDS)