The diagnostic value of perpendicular vascular patterns of vocal cords defined by narrow-band imaging.

PURPOSE: According to the classification of glottic lesions by narrow-band imaging (NBI) proposed by the European Laryngological Society (ELS), lesions without perpendicular patterns are benign, while wide- and narrow-angled perpendicular lesions include both papilloma and carcinoma/high-grade lesions, respectively. The purpose of the study was to investigate the effectiveness of the ELS classification. METHODS: One hundred and forty four patients with glottic lesions underwent microlaryngoscopy with NBI. The affected vocal cords (arm A) were histologically analysed. The unaffected vocal cords (arm B) were not histologically analysed and were considered to be true negatives if no suspicious changes appeared during the follow-up. The vocal cords from arm A were categorised into three groups-those with a benign disease (papilloma excluded), those with a carcinoma/high-grade lesion and those with papilloma. The ratio of vascular patterns was determined and the groups were statistically compared using the Chi-square test. RESULTS: Perpendicular patterns were identified only in 9.3% (9/97) of those in the benign group (without papilloma). Wide-angled patterns were mainly identified in cases of papilloma (80%, 12/15), while the narrow-angled ones were mostly identified in cases of carcinoma and high-grade lesions (96.2%, 76/79) (P < 0.001). The sensitivity, specificity, positive and negative predictive values and accuracy were 98%, 95%, 88%, 99% and 95%, respectively. CONCLUSION: The ELS classification of vocal cord lesions by NBI is effective in differentiating between carcinoma/high-grade lesions and papilloma and the remaining benign lesions of the vocal cords.

Molecular characterization, prevalence and clinical relevance of Phodopus sungorus papillomavirus type 1 (PsuPV1) naturally infecting Siberian hamsters (Phodopus sungorus).

Phodopus sungorus papillomavirus type 1 (PsuPV1), naturally infecting Siberian hamsters (Phodopus sungorus) and clustering in the genus Pipapillomavirus (Pi-PV), is only the second PV type isolated from the subfamily of hamsters. In silico analysis of three independent complete viral genomes obtained from cervical adenocarcinoma, oral squamous cell carcinoma and normal oral mucosa revealed that PsuPV1 encodes characteristic viral proteins (E1, E2, E4, E6, E7, L1 and L2) with conserved functional domains and a highly conserved non-coding region. The overall high prevalence (102/114; 89.5 %) of PsuPV1 infection in normal oral and anogenital mucosa suggests that asymptomatic infection with PsuPV1 is very frequent in healthy Siberian hamsters from an early age onward, and that the virus is often transmitted between both anatomical sites. Using type-specific real-time PCR and chromogenic in situ hybridization, the presence of PsuPV1 was additionally detected in several investigated tumours (cervical adenocarcinoma, cervical adenomyoma, vaginal carcinoma in situ, ovarian granulosa cell tumour, mammary ductal carcinoma, oral fibrosarcoma, hibernoma and squamous cell papilloma) and normal tissues of adult animals. In the tissue sample of the oral squamous cell carcinoma individual, punctuated PsuPV1-specific in situ hybridization spots were detected within the nuclei of infected animal cells, suggesting viral integration into the host genome and a potential etiological association of PsuPV1 with sporadic cases of this neoplasm.

Laryngeal Squamous Intraepithelial Lesions: An Updated Review on Etiology, Classification, Molecular Changes, and Treatment.

Laryngeal carcinogenesis is a multistep process, characterized by an accumulation of genetic changes associated with architectural and cytologic alterations, ranging from squamous hyperplasia to carcinoma in situ and encompassed by the terminology of squamous intraepithelial lesions (SILs). The etiology, classification, genetic changes, and malignant progression of these lesions are reviewed. Tobacco remains the principal etiological factor with gastroesophageal reflux disease recently considered as a possible factor. In contrast, there is little evidence that microbiological agents, especially human papillomavirus infection, are frequently involved in laryngeal carcinogenesis and probably <10% of SILs are driven by biologically active human papillomavirus infection. Light microscopy, despite a degree of subjectivity, remains the mainstay of accurate diagnosis, prognosis, and guidance for a patient's treatment. The currently used classifications, the dysplasia system, squamous intraepithelial neoplasia, and the Ljubljana classification, reflect different standpoints on this important topic. The modified Ljubljana classification, with good interobserver agreement, could be considered as a proposal for a unified classification of laryngeal SILs. This review also briefly discusses recently discovered genetic changes, such as CDKN2A and CTNNB1 genes, and chromosome instability of chromosomes 1 and 7; however, none of these can at present improve histologic diagnosis. Malignant progression of precursor lesions varies from 2% to 74%, according to different studies. Cold-steel microinstruments, CO2 laser, and radiotherapy are used to treat the different grades of precursor lesions. There is as yet no worldwide agreement on the treatment of high-grade lesions and carcinoma in situ.

Incidence trends in head and neck squamous cell carcinoma in Slovenia, 1983-2009: role of human papillomavirus infection.

An increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC) was observed in several population-based registries and has been attributed to human papillomavirus (HPV) infection. In the present study, we aimed to assess the contribution of HPV infection to the burden of mucosal head and neck squamous cell carcinoma (HNSCC) in Slovenia. For this purpose, data from the nationwide Cancer Registry of Slovenia for cases diagnosed between 1983 and 2009 were analyzed to determine time trends of age-adjusted incidence rates and survival in terms of annual percentage change (APC) for HNSCC in potentially HPV-related and HPV-unrelated sites. In addition, determination of p16 protein, HPV DNA and E6/E7 mRNA was performed in a cohort of OPSCC patients identified from the prospective database for the years 2007-2008. In total, 2,862 cases of HNSCC in potentially HPV-related sites and 7,006 cases in potentially HPV-unrelated sites were identified with decreased incidence observed over the time period in both groups (-0.58; 95 % CI -1.28 to -0.13 and -0.90; 95 % CI -1.23 to -0.57). Regardless of the group, incidence trends for both genders showed a significant decrease in men and increase in women. In a cohort of 99 OPSCC patients diagnosed between 2007 and 2008, 20 (20.2 %) patients had HPV positive tumors and exhibited a superior outcome compared to HPV-negative patients. In conclusion, results of the epidemiologic and histopathologic study confirmed that HPV infection had no major impact on the incidence trends in the Slovenian patients with HNSCC and, specifically, OPSCC during the studied period.

Prognostic value of some tumor markers in unresectable stage IV oropharyngeal carcinoma patients treated with concomitant radiochemotherapy.

BACKGROUND: The aim of the study was to investigate how the expression of tumor markers p21, p27, p53, cyclin D1, EGFR, Ki-67, and CD31 influenced the outcome of advanced inoperable oropharyngeal carcinoma patients, treated with concomitant radiochemotherapy. PATIENTS AND METHODS: The pretreatment biopsy specimens of 74 consecutive patients with inoperable stage IV oropharyngeal squamous cell carcinoma treated with concomitant radiochemotherapy were in retrospective study processed by immunochemistry for p21, p27, p53, cyclin D1, EGFR, Ki-67, and CD31. Disease-free survival (DFS) was assessed according to the expression of tumor markers. RESULTS: Patients with a high expression of p21 (≥10%), p27 (>50%), Ki-67 (>50%), CD31 (>130 vessels/mm2) and low expression of p53 (<10%), cyclin D1 (<10%) and EGFR (<10%) (favorable levels - FL) had better DFS than patients with a low expression of p21 (<10%), p27 (≤50%), Ki-67 (≤50%), CD31 (<130 vessels/mm2) and high expression of p53 (≥10%), cyclin D1 (≥10%) and EGFR (≥10%) (unfavorable levels - UL). However, statistical significance in survival between FL and UL was achieved only for p27 and cyclin D1. DFS significantly decreased with an increasing number of markers with an unfavorable level per tumor (1-4 vs. 5-7) (78% vs. 32%, respectively; p = 0.004). The number of markers per tumor with UL of expression retained prognostic significance also in multivariate analysis. CONCLUSIONS: Statistical significance in survival between FL and UL emerged only for p27 and cyclin D1. The number of markers per tumor with UL of expression was an independent prognostic factor for an adverse outcome.

Verrucous carcinoma of the head and neck - not a human papillomavirus-related tumour?

Association between verrucous carcinoma (VC) of the head and neck and human papillomaviruses (HPV) is highly controversial. Previous prevalence studies focused mostly on α-PV, while little is known about other PV genera. Our aim was to investigate the prevalence of a broad spectrum of HPV in VC of the head and neck using sensitive and specific molecular assays. Formalin-fixed, paraffin-embedded samples of 30 VC and 30 location-matched normal tissue samples were analysed, by using six different polymerase chain reaction-based methods targeting DNA of at least 87 HPV types from α-PV, ß-PV, γ-PV and µ-PV genera, and immunohistochemistry against p16 protein. α-PV, γ-PV and µ-PV were not detected. ß-PV DNA was detected in 5/30 VC (16.7%) and in 18/30 normal tissue samples (60.0%): HPV-19, -24 and -36 were identified in VC, and HPV-5, -9, -12, -23, -24, -38, -47, -49 and -96 in normal tissue, whereas HPV type was not determined in 2/5 cases of VC and in 6/18 normal tissue samples. p16 expression was detected in a subset of samples and was higher in VC than in normal tissue. However, the reaction was predominantly cytoplasmic and only occasionally nuclear, and the extent of staining did not exceed 75%. Our results indicate that α-PV, γ-PV and µ-PV are not associated with aetiopathogenesis of VC of the head and neck. ß-PV DNA in a subset of VC and normal tissue might reflect incidental colonization, but its potential biological significance needs further investigation.

Evaluation of a new grading system for laryngeal squamous intraepithelial lesions--a proposed unified classification.

AIMS: To verify the applicability, reproducibility and predictive value of a proposed unified classification (amended Ljubljana classification) for laryngeal squamous intraepithelial lesions (SILs). METHODS AND RESULTS: Six internationally recognized experts and three pathologists from Ljubljana contributed to this study by evaluating a set of laryngeal SILs using the new system: low-grade SIL, high-grade SIL, and carcinoma in situ (CIS). The overall agreement among reviewers was good. Overall unweighted and weighted κ-values and 95% confidence intervals were 0.75 (0.65-0.84) and 0.80 (0.71-0.87), respectively. The results were stratified between the international reviewers and the Ljubljana pathologists. The former had good overall agreement, and the latter had very good agreement. Kaplan-Meier survival curves showed a significant difference (P < 0.0001) between patients with low-grade and high-grade SILs; 19 of 1204 patients with low-grade SILs and 30 of 240 patients with high-grade SILs progressed to malignancy in 2-15 years and in 2-26 years, respectively. CONCLUSIONS: The proposed modification to the Ljubljana classification provides clear morphological criteria for defining the prognostic groups. The criteria facilitate better interobserver agreement than previous systems, and the retrospective follow-up study demonstrates a highly significant difference in the risk of malignant progression between low-grade and high-grade SILs.

Human papilloma virus vaccination in patients with an aggressive course of recurrent respiratory papillomatosis.

In the case of an aggressive course of recurrent respiratory papillomatosis (RRP), adjuvant therapy can be used besides surgery. The aim of the study was to investigate the influence of vaccination with a quadrivalent vaccine against human papilloma viruses (HPV) types 6, 11, 16 and 18 on the course of RRP. Eleven subjects aged 13-46 years with a rapid growth of laryngeal papillomas were included in the study. They were vaccinated with three doses of the quadrivalent prophylactic HPV vaccine (Silgard(®), MSD) and followed up for 12-52 months. The intervals between the successive surgical procedures, the extension of the disease (Derkay score) at each surgery, and the number of surgical procedures per year before vaccination and after its completion were compared. The mean interval between the surgical procedures was 271.2 days before the vaccination and 537.4 days after it (p = 0.034). The mean number of surgeries per year was 2.16 before the vaccination and 0.93 after it (p = 0.022). The Derkay score did not change significantly after vaccination. Complete remission of the disease was observed in one patient, partial response to the vaccination was observed in seven patients and no response was observed in three patients. In conclusion, vaccination with the quadrivalent HPV vaccine can favorably influence the course of RRP in patients with the rapid growth of the papillomas. It significantly prolongs the intervals between the surgical procedures and reduces the number of procedures needed in the majority of patients. The present investigation can serve as a pilot study for further research. For a final conclusion a longer follow-up and studies on more patients are necessary.

Identical human papillomavirus (HPV) genomic variants persist in recurrent respiratory papillomatosis for up to 22 years.

Seventy initial and 125 follow-up tissue specimens of laryngeal papillomas, obtained from 70 patients who had had recurrent respiratory papillomatosis for from 1-22 years, were investigated for the presence of human papillomavirus (HPV) DNA and HPV E5a, LCR and/or full-length genomic variants. HPV-6 was found in 130/195, HPV-11 in 63/195, and HPV-6/HPV-11 in 2/195 samples. Within 67/70 (95.7%) patients, all follow-up HPV isolates genetically matched completely initial HPV isolate over the highly variable parts of the genome or over the entire genome. Frequent recurrence of laryngeal papillomas is a consequence of long-term persistence of the identical initial HPV genomic variant.

Expression of stefin A is of prognostic significance in squamous cell carcinoma of the head and neck.

Lysosomal proteases cathepsins B and L (CB, CL) and their endogenous inhibitors stefins A and B (SA, SB) are associated with tumor cell invasion and metastasis. The purpose of this study was to determine the immunohistochemical (IHC) localization of these parameters in tissue sections of 65 patients with operable head and neck squamous cell carcinoma (HNSCC) and to evaluate the prognostic significance of the observed IHC reactions. In SCC cells, a dot-like staining pattern for CB and CL was especially polarized in the perinuclear area and for stefins the characteristic IHC pattern was a diffuse cytoplasmic reaction. Higher SA immunoreactivity scores were found prognostically advantageous in univariate survival analysis [locoregional control (LRC), P = 0.003; disease-free survival (DFS), P = 0.023; disease-specific survival (DSS), P = 0.030] and appeared significant for predicting LRC (P = 0.019) in a multivariate setting. Among node-positive extracapsular extension-negative patients, SA positivity correlated with a favorable outcome (LRC, P = 0.094; DFS, P = 0.013; DSS, P = 0.012). In conclusion, SA immunoreactivity in tumor cells was related to a favorable prognosis. In the neck node-positive extracapsular extension-negative subgroup, SA immunoreactivity scores can be used to identify patients at increased risk for disease relapse.

Tumor-specific and gender-specific pre-vaccination distribution of human papillomavirus types 6 and 11 in anogenital warts and laryngeal papillomas: a study on 574 tissue specimens.

Anogenital warts and laryngeal papillomas are two most important benign tumors etiologically linked with HPV. In the study, which included both the largest number of laryngeal papilloma tissue specimens (152 specimens from 152 patients) to date and the largest number of prospectively collected and histologically confirmed tissue specimens of anogenital warts obtained from both genders (422 specimens from 315 patients), HPV DNA was detected in 413/422 (97.9%) of anogenital warts and 139/152 (91.4%) of laryngeal papillomas. HPV-6 and/or HPV-11 were detected in 291/315 (92.4%) patients with anogenital warts and in 138/152 (90.8%) patients with laryngeal papillomas, indicating that the great majority of both tumors could be prevented with prophylactic quadrivalent vaccine. The HPV-6 gender-specific distribution in both anogenital warts and laryngeal papillomas was not statistically significant. In contrast, HPV-11 was found almost three times more often in males than in females with anogenital warts (16.5% vs. 6.3%; P = 0.008), with a gender neutral HPV-11 type distribution in laryngeal papillomas. The overall HPV DNA prevalence in anogenital warts was significantly different from that in laryngeal papillomas (97.1% vs. 91.4%; P = 0.01). In the first comparison of the HPV-6/HPV-11 type-specific distribution between patients suffering from anogenital warts and laryngeal papillomas with the same geographic and ethnic background, a significant imbalance in tumor-specific distribution of HPV-6 and HPV-11 was identified: HPV-6 was statistically more often present in anogenital warts than in laryngeal papillomas (79.0% vs. 59.2%; P = 0.000013), whereas HPV-11 was statistically more frequent in laryngeal papillomas than in anogenital warts (28.9% vs. 12.4%; P = 0.00003).

Differential expression of microRNAs miR-21, miR-31, miR-203, miR-125a-5p and miR-125b and proteins PTEN and p63 in verrucous carcinoma of the head and neck.

AIMS: To investigate the expression of microRNAs miR-21, miR-31, miR-203, miR-125a-5p and miR-125b and proteins phosphatase and tensin homologue (PTEN) and p63 in verrucous carcinoma (VC) of the head and neck. METHODS AND RESULTS: Thirty cases of VC, 50 cases of conventional squamous cell carcinoma (SCC) and 30 samples of normal epithelium of the head and neck were included. Real-time polymerase chain reaction and immunohistochemistry were used to analyse the expression of microRNAs and proteins, respectively. In comparison to normal epithelium, miR-21 was overexpressed in both VC and SCC and miR-31 was overexpressed in VC and in well- and moderately differentiated SCC. Levels of miR-203 were elevated in VC but unaltered or reduced in SCC, and levels of miR-125a-5p and miR-125b were reduced in VC but unaltered in SCC. PTEN was down-regulated in both VC and SCC, whereas p63 was down-regulated in VC but up-regulated in SCC. Differential expression of p63 in VC correlated inversely with the expression of miR-21 and miR-203. CONCLUSIONS: Differences between VC, SCC and normal epithelium in expression profiles of investigated molecules indicate their association with the pathogenesis and clinicopathological characteristics of VC. Our results suggest that some microRNAs and proteins, particularly miR-125b, miR-203 and p63, might be useful in the diagnosis of VC.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Hypopharynx, Larynx, Trachea and Parapharyngeal Space.

In this article, we review the chapter on tumors of the larynx, hypopharynx, trachea and parapharyngeal space in the new edition of the WHO book, focusing on the new developments in comparison to the previous edition. Squamous cell carcinoma (SCC) and its variants are by far the most common malignancies at these locations, with very limited new insights. The most important is the introduction of new targeted treatment-checkpoint inhibitors, with a new task for pathologists, who may help to predict the response to treatment by analyzing the expression of targeted proteins in biopsy samples. Precancerous lesions remain a controversial topic and, similarly to other organs, it is acceptable to use the terms "dysplasia" or "squamous intraepithelial lesion" (SIL), but there is a slight difference between low-grade dysplasia and low-grade SIL: in the former, mild atypia must be present, while the latter also includes hyperplastic epithelium without atypia. Two approaches have been proposed: a two-tiered system with low- and high-grade dysplasia/SIL and a three-tiered system with an additional category, carcinoma in situ. We are still searching for reliable diagnostic markers to surpass the subjectivity in biopsy diagnosis, with a few potential candidate markers on the horizon, e.g., stem cell markers. Other tumors are rare at these locations, e.g., hematolymphoid, neuroendocrine and salivary gland neoplasms, and are no longer included in Chapter 3. They must be diagnosed according to criteria described in specific chapters. The same holds true for soft tissue tumors, with the exception of cartilaginous neoplasms, which are still included in Chapter 3.

Prevaccination genomic diversity of human papillomavirus genotype 11: a study on 63 clinical isolates and 10 full-length genome sequences.

Prevaccination genomic diversity of human papillomavirus genotype 11 (HPV 11) was established by sequencing 40% of the genome of 63 clinical isolates obtained from an ethnogeographically closed Caucasian cohort, and full-length genome sequencing of the ten most divergent isolates. In the study, which included the largest number of isolates to date, by analyzing pooled L1, LCR, E6, E5a, and E5b sequences (3,217 bp) of an individual isolate, a total of 23 genomic variants were identified, of which three (5 isolates) and twenty (58 isolates) corresponded to prototypic and non-prototypic variant groups, respectively. Several novel, potentially important mutations are described. Full-length genome sequences of ten isolates revealed more than 99% similarity to the HPV 11 prototype isolate. The minimum genomic distance between the full-length sequences of genomic variants and the prototype was 3 point mutations and 2 inserts and the maximum distance 31 point mutations, one insertion and one deletion. Within the ethnogeographically closed cohort investigated in this study, HPV 11 was shown to be less polymorphic in comparison to the majority of HPV genotypes studied to date.

Usefulness of high-risk human papillomavirus mRNA silver in situ hybridization diagnostic assay in oropharyngeal squamous cell carcinomas.

AIMS: The transcriptional activity of high-risk human papillomaviruses (HR-HPV) within oropharyngeal squamous cell carcinomas (OPSCC) has been linked to improved survival of patients. HR-HPV mRNA silver in situ hybridization (SISH) was evaluated on a cohort of OPSCC and compared with viral HPV DNA tests and p16 expression. Clinical outcomes of HPV-driven OPSCC and non-HPV related OPSCC were also studied. METHODS: We evaluated 67 OPSCC and 3 papillomas, obtained from 62 patients, for detection of HR-HPV DNA by PCR tests. The positive samples were additionally studied by the SISH method using three probes of HPV16, HPV18, and HP33, and for p16 expression detected by immunohistochemistry. SISH assays were evaluated for the presence/number and intensity of signals in cancer cells. Prognostic significance of HPV status in our cohort was evaluated with univariate and multivariate statistics. RESULTS: According to the HR-HPV PCR tests, 46 (69%) OPSCC cases were HPV positive, while three papillomas were negative. Of total 46 HPV-positive OPSCCs, 43 cases were also SISH-positive, while p16 overexpression was found in 45 of 46 HPV positive OPSCC cases. In OPSCC specimens, the sensitivity and specificity of the combined SISH probes (HPV16 and 33) were both 100.00%, when compared to HPV PCR. HPV positivity of the tumors appeared significant for predicting progression-free survival, cause specific survival and overall survival in a multivariate setting. CONCLUSIONS: The recently developed mRNA SISH methodology can detect HPV-driven OPSCCs without any additional test in 79% of cases. Positive SISH signals enable the visualization of viral transcripts required to recognize clinically relevant HPV infection. However, rare and tiny signals require an experienced pathologist to establish a consensus interpretation of results. The currently applied HR-HPV mRNA SISH analysis may serve as a groundwork for additional studies.

Laryngeal Myxoglobulosis: A Rare Histologic Variant of Mucocele. The First Reported Case.

Myxoglobulosis is a rare histologic variant of mucocele that is characterized by transformation of mucin into eosinophilic globules. The globules frequently demonstrate a lamellar pattern and are surrounded by an inflammatory cell infiltrate. Myxoglobulosis has not yet been described in laryngeal mucosa. A 62 year old man presented for a check-up with hoarseness of 2 months duration. He was a current smoker and reported a 40 year habit. An asymmetrical swelling along the length of both vocal cords was consistent with a clinical diagnosis of Reinke's edema. The histopathologic examination demonstrated bilateral pseudocyst formation within Reinke's space. Extravasated mucin was present in the form of eosinophilic globules that filled the left Reinke's space almost entirely and were also seen on the right side. The pseudocyst, mucinous globules, and accompanying inflammatory cells were characteristic of myxoglobulosis. The sequelae of nicotine abuse, including inflammation, increased mucous secretion, and a rasping cough, are considered to be the main etiological factors of laryngeal myxoglobulosis. The patient had no evidence of voice disorder at 18 month follow-up. This case report contributes to the recognition of an exceptionally rare histologic variant of laryngeal mucocele.

Risk factors for the development of high-grade dysplasia and carcinoma in patients with laryngeal squamous cell papillomas: Large retrospective cohort study.

BACKGROUND: The incidence and risk factors for the development of high-grade dysplasia (HG-D) and laryngeal squamous cell carcinoma (LSCC) were assessed in patients with laryngeal squamous cell papillomas (LSP). METHODS: Clinical data, human papillomaviruses (HPV) typing, HPV E6/E7 mRNA in situ hybridization, and sequencing of host genes in LSP biopsies of 163 patients were analyzed. RESULTS: Progression to HG-D and LSCC was identified in 21.5% and 4.3% of LSP patients, respectively. A more advanced age at LSP onset and lack of HPV infection were detected as risk factors for the development of HG-D and LSCC (P < .05). The identification of HG-D was associated with its progression to LSCC (P < .05). Host gene mutations were identified in 3 of 7 patients with LSCC. CONCLUSIONS: The histological monitoring of LSP and HPV typing are necessary for early detection of epithelial changes. Further research is needed to elucidate the role of host gene mutations in LSCC transformation.

Laryngeal Dysplasia: Persisting Dilemmas, Disagreements and Unsolved Problems-A Short Review.

We present the historical review and current state of the histopathological classifications and terminology of laryngeal precursor lesions. Attention to recent genetic findings is also presented; although in need of additional confirmation, these raise possibility for early detection of patients at risk of dysplasia progression. Although a number of identified genetic alterations with a promising diagnostic and prognostic value are emerging, none of the known genetic alterations can be currently implemented in clinical practice as a completely reliable diagnostic and/or prognostic marker. Regarding the terminology of precursor lesions, dysplasia remains the most frequently used term, but squamous intraepithelial lesion can be used as a synonym as well. Histological findings, in spite of certain degree of subjectivity, remain at present the most reliable method for an accurate diagnosis. The current 2017 WHO classification seems to successfully stratify risk of malignant progression, with a significantly different risk of malignant progression between low-grade dysplasia and high-grade dysplasia. In case of pronounced architectural disorders, severe cellular and nuclear atypias, and an increased number of mitoses, also atypical form, the high-grade dysplasia and carcinoma in situ can be separated. The Slovenian tertiary centers have a policy of surgical removal of high-grade SILs and life-long close follow-up. Radiotherapy is reserved for more pronounced intraepithelial lesions classified as carcinoma in situ and invasive cancer. Such a distinction can facilitate clinical decision to use radiotherapy if complete surgical removal is not possible.

Current review on squamous intraepithelial lesions of the larynx.

Squamous intraepithelial lesions (SILs) of the larynx, clinically usually defined as leukoplakia and chronic laryngitis, have remained the main controversial topic in laryngeal pathology for decades as regards classification, histological diagnosis and treatment. SILs are caused by smoking and alcohol abuse. There is also mounting evidence that gastroesophageal reflux is a potential aetiological factor. Human papillomavirus infection seems to play little if any role in laryngeal carcinogenesis. Histological classification of SILs is the central disputed aspect of these lesions. There are as yet no generally accepted criteria for histological grading of laryngeal SILs. Three currently used classifications of SILs are reviewed here: the dysplasia system, the Ljubljana classification and the binary system of squamous intraepithelial neoplasia. One of the most important issues of SILs is the risk of malignant transformation. Data in the literature are controversial because of inconsistent use of morphological criteria in different classifications. It is often difficult for clinicians to agree on the most appropriate therapeutic option for a particular grade of SIL that has been diagnosed. Transition from normal epithelium to SILs and squamous cell carcinoma is related to progressive accumulation of genetic changes leading to a clonal population of transformed epithelial cells. Despite extensive research into these genetic changes in laryngeal carcinogenesis, reliable genetic markers with diagnostic and prognostic value are still lacking.

Transcription factors Snail, Slug, Twist, and SIP1 in spindle cell carcinoma of the head and neck.

Spindle cell carcinoma (SpCC) is a biphasic tumor composed of squamous cell carcinoma (SCC) and malignant spindle cells. There is mounting evidence that epithelial-mesenchymal transition (EMT) plays an important role in the pathogenesis of SpCC. Transcription repression has recently emerged as a fundamental mechanism triggering EMT in experimental models. Our aim is to analyze the expression of transcription repressors Snail, Slug, Twist, and SIP1 in SpCC of the head and neck in comparison to SCC, matched for location and stage. Thirty cases of SpCC and 30 cases of SCC of the head and neck were included. Snail, Slug, Twist, and SIP1 expression was analyzed on mRNA and protein levels, using real-time reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. By RT-PCR, we found upregulation of mRNA for transcription factors Snail, Slug, Twist, and SIP1 in SpCC when compared to SCC. This upregulation was statistically significant for Slug, Twist, and SIP1 but nonsignificant for Snail. Immunohistochemistry was performed for Snail, Slug, and SIP1 and demonstrated a positive reaction for Slug and SIP1 in all cases and for Snail in two thirds of SpCC cases. Our finding of upregulation of all four tested transcription factors supports the hypothesis that EMT plays an important role in the pathogenesis of SpCC of the head and neck.