Argyrophilia in nucleolar organizer regions (AgNOR) in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of the salivary glands

Polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma: distinct architectural composition revealed by collagen IV, laminin and their integrin ligands (alpha2beta1 and alpha3beta1)

AIMS

Polymorphous low-grade adenocarcinoma (PLGA) and adenoid cystic carcinoma (ACC) are malignant salivary gland tumours bearing many similar histological patterns. This study was undertaken to show how the presence and distribution of collagen IV and laminin, and their ligands (integrin alpha2beta1 and alpha3beta1 components), can reveal histoarchitectural differences which distinguish these two entities.

METHODS AND RESULTS

Five cases of ACC and five cases of PLGA from the archives of the Oral Pathology Department of the School of Dentistry of the São Paulo University were submitted to immunostaining with the antibodies to collagen IV, laminin, and integrins alpha2beta1 and alpha3beta1 using the streptavidin-biotin-peroxidase technique. Positive and negative controls were included. PLGA showed a thin line of collagen IV and laminin surrounding structures composed of a single cell layer. Integrins were expressed as a widespread and granular pattern. A thick line of collagen and laminin was observed around the neoplastic structures of ACC. Both integrins were expressed in intercellular spaces and around luminal spaces of tubular structures.

CONCLUSIONS

Collagen IV and laminin, and their integrin ligands, are useful in demonstrating that neoplastic ductal units of PLGA are composed of a single cell layer, being distinct from ACC which contains structures composed of two layers of neoplastic cells.

Proliferating cell nuclear antigen expression in mucoepidermoid carcinoma of salivary glands

CONTEXT

Among the cytological and morphological properties of mucoepidermoid carcinoma, one of the most important criteria for measuring its biological behavior and aggressiveness is cell proliferation. In this way, immunohistochemical markers of cell proliferation have been found to be useful in tumor classification and have formed part of the prognostic and therapeutic studies of these pathologies.

OBJECTIVE

To analyze 11 cases of mucoepidermoid carcinoma (MEC) using the proliferation activity marker (PCNA) and to determine its relationship to the grade of malignancy of these tumors.

DESIGN

Correlation study.

SETTING

Head and Neck Surgery Service of Heliópolis Hospital, São Paulo, Brazil.

SAMPLE

Slides of 11 cases of primary mucoepidermoid carcinomas of salivary glands were prepared according to routine techniques employed in the Oral Pathology Department of the Dentistry Faculty of São Paulo University, Brazil. They were fixed in a 10% formaldehyde solution and stained with hematoxylin and eosin. After this preparation the tumors were classified as low, intermediate and high grade of malignancy, according to the criteria established by Seifert & Sobin and Auclair, Goode & Ellis. The slides were sent for immunohistochemical processing to evaluate the positivity of proliferating cell nuclear antigen using the streptavidin biotin technique.

MAIN MEASUREMENT

The correlation between proliferating cell nuclear antigen expression and the histological malignancy grade in mucoepidermoid carcinoma of salivary glands.

RESULTS

there were 4 cases (36%) of low grade, 4 cases (36%) of intermediate grade and 3 cases (27%) of high grade of malignancy. After a comparative study between histological features and immunohistochemical analysis, significant differences were observed (P < 0.01) for low, intermediate and high grades: 16.04%, 26.98% and 56.98% of proliferating cell nuclear antigen expression in mucoepidermoid carcinoma, respectively.

CONCLUSION

The proliferating cell nuclear antigen expression increases with the grade of malignancy in mucoepidermoid carcinoma of salivary glands.

Evaluation of p53, PCNA, Ki-67, MDM2 and AgNOR in oral peripheral and central giant cell lesions

OBJECTIVES

Peripheral giant cell lesion (PGCL) and central giant cell lesion (CGCL) of the jaws have a distinct clinical behaviour. Whether such biological differences are supported by a distinct pattern of proliferation markers or cell cycle associated proteins expression is not known. Therefore the purpose of the present study was to compare the immunohistochemical expression of p53, MDM2, Ki-67, PCNA and the histochemical expression of argyrophilic nuclear organiser region (AgNOR) on PGCL and CGCL of the jaws.

MATERIALS AND METHODS

Paraffin wax blocks of 14 cases of PGCL and 12 cases of CGCL were retrieved. A biotin-streptavidin amplified system was used for identification of the antigens. The AgNOR number was also evaluated.

RESULTS

Ki-67 immunoreactivity was greater in the mononuclear cells of PGCL compared to CGCL. PCNA and AgNOR staining were similar in PGCL and CGCL. Prominent MDM2 immunoreactivity was observed in all tissues investigated. By contrast, there was no p53 immunoreactivity.

CONCLUSIONS

Although CGCL present a more aggressive clinical behaviour, it has a decreased proliferative activity compared to PGCL. Finally, p53, MDM2, PCNA, Ki-67 immunohistochemical expression and AgNOR histochemical expression do not reflect their distinct biological behaviour.

PCNA/AgNOR and Ki-67/AgNOR double staining in oral squamous cell carcinoma

This study was performed on oral squamous cell carcinomas (OSCC) in order to investigate the relation between the number of interphase silver-stained nucleolar organizer regions (AgNORs) and the immunolabeling of proliferation-associated markers, using antibodies to Ki-67 and proliferating cell nuclear antigen (PCNA). Fifteen consecutive cases of oral squamous cell carcinoma were used and a double staining technique was performed in order to quantify the number of NORs in PCNA-positive and -negative cells as well as in Ki-67-positive and -negative cells. Our results showed a higher mean number of AgNORs in PCNA- and Ki-67-positive cells than in PCNA- and Ki-67-negative cells. We concluded that there is an association between cell proliferation and AgNOR score in OSCC.

Proliferative activity in peripheral ossifying fibroma and ossifying fibroma

A proliferative activity study analysing morphometric and quantitative aspects of nucleolar organizer regions (NORs) and proliferating cell nuclear antigen (PCNA) expression was conducted in 10 cases of peripheral ossifying fibroma (POF) and 10 cases of ossifying fibroma (OF). For NOR identification, the silver staining technique (AgNOR technique) was used. PCNA expression was determined by immunohistochemical staining using the PC10 antibody. The AgNOR analysis for the two lesions showed a profile characteristic of benign lesions. OF showed higher AgNOR number and PCNA expression than POF. Our results suggest increased proliferative activity in OF compared with POF.

Silver staining method for nucleolar organizer regions in cervical smears

The distribution of nucleolar organizer regions (NORs) was studied in Papanicolaou preparations of cervical smears in order to distinguish benign from preneoplastic lesions. Destained smears (six defined as normal, six as inflammatory with squamous metaplasia, six as CIN I, six as CIN II, and five as CIN III) were submitted to the Ag-NOR method after staining with Orange G and EA36. Ag-NOR count was performed in previously outlined fields on the smears. Statistically significant differences (P < .05) were found between the normal smears, inflammatory smears with squamous metaplasia, and each grade of CIN. We conclude that the Ag-NOR technique could be useful to evaluate cervical smears of doubtful interpretation, using previous demarcation of the abnormal fields/cells.

Massive pleural effusion as isolated manifestation of metastatic spread of salivary adenoid cystic carcinoma

Adenoid cystic carcinoma is a low-grade malignant neoplasm that arises preferentially in the major and/or minor salivary glands. While it has a tendency to spread locally, distant metastases have been described occasionally. This case report describes a patient with a massive pleural effusion as primary manifestation of metastatic adenoid cystic carcinoma. This is a very uncommon, yet treatable, occurrence.