Immunohistochemical expression of basement membrane proteins of verrucous carcinoma of the oral mucosa

Oral verrucous carcinoma: a diagnostic and therapeutic challenge

BACKGROUND

Verrucous carcinoma is a low-grade variant of squamous cell carcinoma with specific morphologic, cytokinetic and clinical features. Despite low mitotic activity and slow growth, it can infiltrate adjacent tissues in advanced stages but does not metastasize. The most frequently affected site is the oral cavity. The following article provides latest updates in the etiology, clinical presentation, diagnostics and treatment options in oral verrucous carcinoma and discusses the existing dilemmas linked to this unique malignancy.

CONCLUSIONS

Oral verrucous carcinoma must be differentiated from conventional squamous cell carcinoma due to its less aggressive behaviour with a more favourable prognosis. Close communication between clinician and pathologist is mandatory for making a correct diagnosis. Primary surgery with negative surgical margins seems to be the most successful treatment. However, management recommendations are not uniform since they are mostly based on case reports and small retrospective case series. Prospective and pooled multi-institutional studies are therefore needed.

Evaluation of the presence of myofibroblasts and matrix metalloproteinase 1 expression in the stroma of oral verrucous hyperplasia and verrucous carcinoma

Background

Oral verrucous carcinoma is a low-grade subtype of oral squamous cell carcinoma that should be differentiated from oral verrucous hyperplasia, a premalignant lesion. Stromal activated myofibroblasts known as cancer-associated fibroblasts have an active role in the initiation and progression of the cancers via secretion of different molecules including matrix metalloproteinases.

Aims

This study is designed to understand the differences in the presence of myofibroblasts and expression of matrix metalloproteinase-1 in the adjacent stroma of verrucous carcinoma and oral verrucous hyperplasia (OVH).

Settings and Design

Cross-sectional study.

Material and Methods

Twenty-seven OVH, 19 oral verrucous carcinoma (OVC), and 8 cutaneous verrucous carcinoma (CVC) specimens were analyzed for immunohistochemical (IHC) expression of α-smooth muscle actin (αSMA) and MMP-1.

Results

IHC studies for αSMA expression in nonvascular stromal cells of the adjacent stroma revealed mild or no expression in 81.4%, 73.7%, and 62.5% of the cases of OVH, OVC, and CVC groups, respectively. No significant difference was seen in αSMA expression index between OVH and OVC groups (Adj. Sig. = 0.220) and between OVC and CVC groups (Adj. Sig. = 1.00). Pairwise analysis revealed a significant difference in MMP-1 expression index between the groups. No significant correlation was observed between MMP-1 expression index and αSMA expression index in OVH (pv = 0.358) and OVC (pv = 0.388) groups.

Conclusion

The differences in MMP-1 expression between OVH and OVC can be used as an adjunctive aid in challenging cases including disoriented or inadequate samples.

Focus on HPV Infection and the Molecular Mechanisms of Oral Carcinogenesis

This study is focused on the epidemiological characteristics and biomolecular mechanisms that lead to the development of precancerous and cancerous conditions of oral lesions related to Human Papilloma Virus (HPV) infections. Current evidence from the literature demonstrates the role of HPV in potentially malignant oral disorders. Therefore, the underlying biomolecular processes can give arise, or contribute to, benign lesions as well as to oral carcinogenesis.

Expression of Laminin in Oral Squamous Cell Carcinomas

Background and objectives:

Laminin is a significant basement membrane (BM) glycoprotein, the expression of which reflects BM integrity more precisely than do other ECM proteins. The present study aimed to evaluate laminin expression in oral squamous cell carcinomas OSCC and to determine any associations with clinico-pathological parameters (surgical margin status, lymph node involvement, survival and recurrence).

Methods:

Laminin expression was evaluated in 31 cases of biopsy-proven OSCC by immunohistochemical staining and its association with prognosticators and the Brynes grading system was determined by appropriate statistical analysis.

Results:

We observed a significant increase in linear staining pattern (p<0.001) at the tumour-host interface in well-differentiated OSCC cases, in contrast to poorly differentiated lesions which exhibited intense cytoplasmic expression within tumour cells. Higher cytoplasmic laminin expression was seen in 33.3% of cases with involved surgical margins and 69.2% of cases with lymph node metastasis (along with weak/absent staining of laminin around the tumour-host interface – Basement membrane around tumour islands). Similarly, in 60% of the cases who died and in 81.8% of cases with tumour recurrence, moderately intense cytoplasmic laminin expression was seen within tumour cells. On comparing variables of the Brynes grading system, significant cytoplasmic expression of laminin was linked with mild inflammation (p<0.0016) and increased mitotic activity (p<0.008).

Conclusion:

Based on these observations, immunohistochemical expression of laminin might be useful to evaluate histological differentiation and aggressiveness of OSCCs.

Diagnostic Biomarkers in Oral Verrucous Carcinoma: A Systematic Review

Oral verrucous carcinoma (OVC), a low-grade variant of oral squamous cell carcinoma (OSCC), is most frequently seen in the oral cavity. No clear etiology has been found for this lesion, but human papilloma virus, chewing betel nuts, and ultraviolet radiation are suggested as probable causes. Differential diagnosis of OVC is challenging for oral pathologists. The aim of this study was to review the molecular-based approaches for differential diagnosis of OVC. An electronic search was conducted in Medline and Scopus from January 2004 to July 2015 limited to English language publications. Published papers on verrucous carcinoma (VC) were found according to the inclusion and exclusion criteria and analyzed qualitatively. Data extraction were performed according to PRISMA statement. A total of 423 articles were reviewed; out of which, 26 articles completely fulfilled the inclusion criteria. Most of the included studies investigated proliferative and apoptotic biomarkers such as p53 and Ki67. No definite conclusion was drawn for cytoskeletal biomarkers due to variability of factors and lack of significant expression. However, it seems that cytokeratin10 (CK 10) can be useful for differentiation of OVC and benign squamous lesions. Among cell surface and extracellular matrix biomarkers tissue biomarkers, matrix metalloproteinase (MMP)-2, -9, CD31 and CD68 seem to be useful for differentiation of OVC and OSCC and glucose transporter-1 (GLUT-1) can help in differentiation of OVC from oral epithelial dysplasia. Differences among OVC, OSCC and normal epithelium in expression profiles of the investigated biomarkers help in their differential diagnosis; although, clinicohistopathological similarities among verrucous hyperplasia, noninvasive OVC and invasive well-differentiated OSCC make the diagnosis difficult. Further studies are required to better differentiate these oral lesions.

Oral verrucous carcinoma: From multifactorial etiology to diverse treatment regimens (Review)

Oral verrucous carcinoma (OVC) is a verrucous variant of oral squamous cell carcinoma (OSCC), which accounts for 2-12% of all oral carcinomas with a 5-year survival rate of only approximately 50%. Enormous effort has been dedicated to this cancer, and the past decades have witnessed significant advances in relevant diagnostic and therapeutic approaches. Currently, there exist three challenges from primary sub-fields of research and clinical practice of the cancer, namely multifactorial etiology, complex molecular mechanism, and deficient treatment. This study reviews the existing literature on the cancer, encompassing its etiology, clinical manifestations and pathology, molecular mechanism, diagnosis and differential diagnosis, and treatment. For improved treatment of OVC, multifactorial etiology analysis, incorporation of effective biomarkers for mechanism illustration, and integration of multidisciplinary modalities are expounded, in an attempt to resolve the challenges and to provide a useful guide for future research in the field.

Mouth Cancer for Clinicians Part 6: Potentially Malignant Disorders

A MEDLINE search early in 2015 revealed more than 250,000 papers on head and neck cancer; over 100,000 on oral cancer; and over 60,000 on mouth cancer. Not all publications contain robust evidence. We endeavour to encapsulate the most important of the latest information and advances now employed in practice, in a form comprehensible to healthcare workers, patients and their carers. This series offers the primary care dental team, in particular, an overview of the aetiopathogenesis, prevention, diagnosis and multidisciplinary care of mouth cancer, the functional and psychosocial implications, and minimization of the impact on the quality of life of patient and family.

CLINICAL RELEVANCE

This article offers the dental team an overview of oral potentially malignant disorders.

miR-19a and SOCS-1 expression in the differential diagnosis of laryngeal (glottic) verrucous squamous cell carcinoma

BACKGROUND

Laryngeal verrucous squamous cell carcinoma (VSCC) is a highly differentiated squamous cell carcinoma (SCC), the diagnosis of which can meet with many pitfalls: benign hyperplastic lesions and conventional SCC are the most important differential diagnoses. The microRNA miR-19a is overexpressed in many solid tumours and regulates the suppressor of cytokine signalling-1 (SOCS-1) expression.

AIMS

The main endpoints were to assess miR-19a and SOCS-1 expression in glottic VSCC, and the former's potential role in differentiating between glottic VSCC, conventional SCC and hyperplastic lesions.

METHODS

The expression of MiR-19a (by reverse transcription and quantitative real-time PCR) and SOCS-1 (by immunohistochemistry, rabbit polyclonal anti-SOCS-1 antibody) was assessed in 11 consecutive cases of glottic VSCC, 20 of papillary hyperplasia and 42 cases of conventional SCC.

RESULTS

Mean miR-19a expression was significantly higher (p = 0.000) in malignant glottic lesions (conventional SCC/VSCC) than in benign conditions. Significant differences in mean miR-19a expression also emerged between conventional SCC and papillary hyperplasia (p = 0.000), and between conventional SCC and VSCC (p = 0.03). miR-19a expression was not statistically associated with SOCS-1 immunoreactivity or immunostaining intensity in VSCC, conventional SCC or papillary hyperplasia.

CONCLUSIONS

Our preliminary outcomes suggest the utility of miR-19a in the challenging differential diagnosis of laryngeal VSCC. Although miR-19a has been found to regulate SOCS-1 expression, this evidence was not confirmed by this investigation.

Verrucous Carcinoma with Oral Submucous Fibrosis: A Rare Case with Brief Review

Oral verrucous carcinoma (VC) is a variant of well differentiated oral squamous cell carcinoma (OSCC) characterized by exophytic over growth. Oral submucous fibrosis (OSMF) is a potentially malignant disorder associated with chronic betel nut chewing habit. The development of OSCC is seen in one-third of the OSMF patients, but the development of VC is rare in such patients. There are very few cases of OSMF with VC reported in literature. Here, present a rare case of an elderly patient with VC in conjunction with OSMF.

Immunohistochemical expression of Type IV Collagen and Autocrine Motility Factor Receptor in Odontogenic Tumours

BACKGROUND

Autocrine motility factor receptor (AMFR) is a tumour motility stimulating protein secreted by tumour cells. The protein encoded by this gene is a glycosylated transmembrane protein and a receptor for autocrine motility factor. It has been known to play a role in progression of neoplastic lesions. Basement membranes are specialized extracellular matrices that serve as structural barriers as well as substrates for cellular interactions. The network of type IV collagen is thought to define the scaffold integrating other components such as laminins and perlecan into highly organized supramolecular architecture. The aim of this study was to determine and evaluate the immunohistochemical expression of Type IV Collagen and Autocrine motility factor receptor in odontogenic lesions.

MATERIALS AND METHODS

Immunohistochemical expression of Type IV Collagen and Autocrine motility factor receptor was evaluated in 31 odontogenic lesions, including unicystic ameloblastoma, multicystic ameloblastoma, keratocystic odontogenic tumour and ameloblastic carcinoma. Normal follicular tissue formed the control.

RESULTS

Maximum expression for Type IV Collagen was seen in multicystic ameloblastoma and minimum expression in keratocystic odontogenic tumour. The maximum expression of AMFR was seen in ameloblastic carcinoma and minimum expression in multicystic ameloblastoma.

CONCLUSION

The results of this study suggested an association of loss of expression of type IV Collagen with progression of lesion. AMFR expression was found to be associated with the aggressive potential of tumours.

[The value of laminin-322 staining in distinguishing between keratoacanthoma, keratoacanthoma with areas of squamous cell carcinoma, and crateriform squamous cell carcinoma]

INTRODUCTION

Keratoacanthoma is a fast-growing crateriform skin tumor. Approximately 25% of such tumors undergo malignant transformation and develop areas of squamous cell carcinoma (SCC). The presence of laminin-322 has been associated with progression to invasive forms of SCC. The aim of this study was to determine whether or not immunohistochemical staining for laminin-322 would be of value in distinguishing between keratoacanthomas, keratoacanthomas with areas of squamous cell carcinoma, and SCCs.

MATERIAL AND METHODS

Seventy-four lesions were selected from the pathology archives of our hospital and divided into 4 groups: 20 keratoacanthomas without SCC, 20 keratoacanthomas with areas of squamous cell carcinoma, 20 invasive SCCs (8 with crateriform morphology) unrelated to keratoacanthoma, and 14 problem lesions (keratoacanthomas with areas suggestive of SCC). All 74 lesions were stained for laminin-322.

RESULTS

Laminin-322 staining was strongly positive both in areas of SCC in keratoacanthomas with malignant transformation and in invasive SCCs (mostly at the invasive front of the SCC). However, in benign keratoacanthomas, it was only weakly positive and furthermore it was confined to isolated cells or small groups of cells. The 14 problem lesions were reexamined after laminin-322 staining and 8 were diagnosed as keratoacanthomas with incipient SCC and 6 as keratoacanthomas without SCC.

CONCLUSIONS

Laminin-322 staining is different in keratoacanthomas and SCCs and would thus be a useful test for differentiating keratoacanthomas from both invasive SCCs and keratoacanthomas with areas of squamous cell carcinoma. It would also be of value in diagnosing keratoacanthomas with areas suggestive of SCC or with incipient SCC.

Distinctive chromosomal instability patterns in oral verrucous and squamous cell carcinomas detected by high-resolution DNA flow cytometry

BACKGROUND

Oral verrucous carcinomas (OVCs) are characterized by better prognosis than oral squamous cell carcinomas (OSCCs). Because chromosomal instability (CIN) in solid tumors is indicative of prognosis, this study investigated whether OVCs and OSCCs were characterized by differences in CIN biomarkers.

METHODS

Fresh or frozen multiple tissue samples were submitted to high-resolution DNA flow cytometry (hr DNA-FCM).

RESULTS

DNA aneuploid sublines were detected in 6 of 9 OVCs (66.7%) and in 20 of 25 OSCCs (80.0%). Multiple DNA aneuploid sublines were observed, respectively, in 2 of 6 (33.3%) DNA aneuploid OVCs and in 14 of 20 (70%) DNA aneuploid OSCCs (P = .163). OVCs were mainly characterized by DNA Index (DI) values in the near-diploid region (DI≠1 and DI < 1.4), whereas aneuploid OSCCs carried most frequently multiple aneuploid sublines with high DI values (DI ≥ 1.4). DNA near-diploid and high aneuploid sublines were, respectively, 87.5% and 12.5% for the OVCs versus 30% and 70% for the OSCCs (P = .004).

CONCLUSIONS

Present data suggest that OVCs are characterized by a lower degree of CIN and tumor heterogeneity than OSCCs, such that they appear as "frozen" in an early stage of DNA near-diploid aneuploidy, as previously observed for oral preneoplastic lesions. These DI characteristics, which can easily be obtained by hr DNA-FCM, appear to reflect the well-known differences in aggressiveness and prognosis of OVCs and OSCCs.