Transitional neoplasms of the naso-lacrimal system: A review of the histopathology and histogenesis

Transitional papilloma (inverted papilloma, Schneiderian papilloma) is a relatively common, benign epithelial neoplasm of the sinonasal tract that also occurs in the lacrimal drainage system. The name transitional papilloma is recommended because it reflects the key histological features required for pathological diagnosis, as well as the histogenesis of the tumour. The histogenesis of the tumour is reviewed, together with its natural history, which is characterized by bone remodelling and destruction, a tendency to recur and to undergo malignant transformation. Biomarkers associated with these features have been identified in the sinonasal tumours and may also be of relevance to the lacrimal sac tumours, although the necessary studies have not yet been undertaken.

Inflammation and apoptosis in malignant transformation of sinonasal inverted papilloma: the role of the bridge molecules, cyclooxygenase-2, and nuclear factor κB

PURPOSE

This study examined the early events in the neoplastic progression of the sinonasal inverted papilloma to squamous cell carcinoma from the viewpoint of chronic inflammation and apoptosis.

MATERIALS AND METHODS

In total, 118 archival slides stained with hematoxylin and eosin from 45 patients were graded according to histopathology (grades I-IV). Their representative portions were transferred to a tissue microarray, sections of which were stained immunohistochemically for cyclooxygenase-2, p53, bax, bcl-2, and nuclear factor κB.

RESULTS

Cyclooxygenase-2 expression was positively correlated with histopathologic grade, with higher expression in advanced grades. p53s were detected in all cores from advanced grades (III, IV), but not in early grades (I, II). The expressions of nuclear factor κB, bax, and bcl-2 were not correlated with the grade.

CONCLUSIONS

A p53 mutation seems be a critical event for the malignant transformation of the sinonasal inverted papilloma. Cyclooxygenase-2-mediated inflammatory signals, activated as a consequence of the p53 mutation, may contribute to promoting the proliferation of the advanced sinonasal inverted papilloma.

Skull base inverted papilloma: a comprehensive review

Skull base inverted papilloma (IP) is an unusual entity for many neurosurgeons. IP is renowned for its high rate of recurrence, its ability to cause local destruction, and its association with malignancy. This paper is a comprehensive review of the reports, studies, and reviews published in the current biomedical literature from 1947 to September 2010 and synthesize this information to focus on its potential invasion to the base of the skull and possible intradural extension. The objective is to familiarize the clinician with the different aspects of this unusual disease. The role of modern diagnostic tools in medical imaging in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The treatment guidelines for IP have undergone a complex evolution that continues today. Radical excision of the tumour is technically difficult and often incomplete. Successful management of IP requires resection of the affected mucosa which could be achieved with open surgery, endoscopic, or combined approach. Radio and chemotherapy were used for certain indications. More optimally research would be a multicenter randomized trials with large size cohorts.

Prevalence of human papillomavirus, Epstein-Barr virus, p21, and p53 expression in sinonasal inverted papilloma, nasal polyp, and hypertrophied turbinate in Hong Kong patients

BACKGROUND

The purpose of this study of human papillomavirus (HPV), Epstein-Barr virus (EBV), p21, and p53 in sinonasal inverted papilloma (IP) was to help elucidate its pathogenesis.

METHODS

Seventy-three IPs, 48 nasal polyps, and 85 hypertrophied turbinates were subjected to HPV polymerase chain reaction (PCR) study. Seventy-three IPs, 30 nasal polyps, and 32 hypertrophied turbinates were subjected to EBV in situ hybridization (ISH), p21, and p53 immunohistochemical (IHC) studies.

RESULTS

HPV was positive in 3 of 73 IPs (4.1%). All specimens were EBV negative. In all, 99% of IPs showed strong and diffuse p21 nuclear reactivity. Most nasal polyps and hypertrophied turbinates showed weak to moderate immunoreactivity of the basal and parabasal cells. Only focal p53 immunoreactivity of the basal and parabasal cells was found in 19% of IPs and 40% of nasal polyps.

CONCLUSIONS

HPV prevalence of our IP is low. EBV is not present in IP. High p21 and low p53 expression in IP suggests a non-p53-dependent regulation pathway.

Immunohistochemical analysis of PCNA, Ki67 and p53 in nasal polyposis and sinonasal inverted papillomas

Immunoreactivity of proliferating cell nuclear antigen (PCNA), Ki67 and p53 in inflammatory nasal polyp and inverted papilloma tissues was investigated. Immunohistochemistry was performed using a standard avidin-biotin-peroxidase method, and the immunoreactivity of PCNA, Ki67 and p53 was quantified by counting immunostained nuclei in at least 1000 epithelial cells. The mean labelling index (percentage of immunostained cells) for PCNA was 40.68 in the inverted papilloma group and 14.73 in the nasal polyp group, and for Ki67 was 15.43 in the inverted papilloma group and 2.64 in the nasal polyp group. Both of these differences between the inverted papilloma and nasal polyp groups were significant. Immunoreactivity for p53 was detected in five (35.7%) inverted papilloma patients and two (9.5%) nasal polyp patients. The increase in epithelial cell proliferation seemed to be greater in inverted papillomas than in inflammatory nasal polyps. Increased epithelial cell proliferation may be involved in the development of inverted papillomas.

Do nasal polyps and inverted papilloma have similar disorders in cell cycle regulation?

BACKGROUND

The aim of this study was to determine the expression of cell cycle regulation genes in patients with inverted papilloma (IP) and compare this with expression in patients with nasal polyps (NPs).

METHODS

Tissue from 18 patients with IP and 5 patients with NPs were stained by immunohistochemistry techniques for p53 and p27. Measurement of the gene expression was performed by three assessors, who we blinded with respect to the specimens.

RESULTS

The mean score for p53 expression (3.33) was significantly higher in the IP group than the NP group (1.46). The mean difference between IP and NPs was 1.80 (CI, 1.15-2.46; p = 0.003). Additionally, we showed in a number of individuals variation in the p53 expression within the same specimen. There was no difference in the mean scores for p27, with the mean difference 0.79 (CI, 0.30-1.89; p = 0.147).

CONCLUSION

Our study established a significantly increased expression of p53 in IP when compared with NPs. Additionally, there appear to be two different cell populations identified within the same specimens, which exhibited variation in their p53 expression.

Nasal cytotoxic and carcinogenic activities of systemically distributed organic chemicals

Toxicity and carcinogenicity in the mucosa of the nasal passages in rodents has been produced by a variety of organic chemicals which are systemically distributed. In this review, 14 such chemicals or classes were identified that produced rodent nasal cytotoxicity, but not carcinogenicity, and 11 were identified that produced nasal carcinogenicity. Most chemicals that affect the nasal mucosa were either concentrated in that tissue or readily activated there, or both. All chemicals with effects in the nasal mucosa that were DNA-reactive, were also carcinogenic, if adequately tested. None of the rodent nasal cytotoxins has been identified as a human systemic nasal toxin. This may reflect the lesser biotransformation activity of human nasal mucosa compared to rodent and the much lower levels of human exposures. None of the rodent carcinogens lacking DNA reactivity has been identified as a nasal carcinogen or other cancer hazard to humans. Some DNA-reactive rodent carcinogens that affect the nasal mucosa, as well as other tissues, have been associated with cancer at various sites in humans, but not the nasal cavity. Thus, findings in only the rodent nasal mucosa do not necessarily predict either a toxic or carcinogenic hazard to that tissue in humans.

Characteristics of nasal inverted papilloma and its malignant transformation: a study of cell proliferation and programmed cell death

BACKGROUND

In nasal inverted papilloma (IP) and its malignant transformation process, abnormal cell growth has been regarded as a altered proliferation of the epithelial cells, while the role of programmed cell death in this process remains to be determined.

METHODS

An apoptotic index was calculated, and the proliferation ability by using Ki67 as a marker was evaluated in the study subjects, which consisted of 15 cases of nasal chronic sinusitis, 23 cases of nasal IP, 9 cases of nasal IP with dysplasia, 8 cases of nasal IP with squamous cell carcinoma (SCC), and 21 cases of primary SCC. In addition, expressions of apoptosis-related molecules p53, Bcl-2, Bax, and Fas were investigated also.

RESULTS

The result showed that the Ki67 index increased in IP and IP with dysplasia. The Ki67 value was further enhanced in SCC within IP and primary SCC. The apoptotic index was low in IP with dysplasia, IP with SCC, and primary SCC. Concerning the expression of apoptosis-related proteins, p53 protein accumulated in IP with dysplasia, IP with SCC, and primary SCC. The p53 overexpression was directly correlated with the Ki67 index in IP and primary SCC diseases. No remarkable differences were found regarding expression of Bcl-2 and Fas productions among these diseases, and Bax protein was decreased only in primary SCC.

CONCLUSION

We concluded that inhibition of apoptosis could be an early sign of IP undergoing malignant transformation. A high proliferative rate was a characteristic of IP-associated malignant diseases.

Novel treatments for recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis is a rare but often severe disease. Although benign in histology, epithelial proliferations may result in progressive hoarseness, stridor, obstruction of the airway and respiratory distress. The current standard of care is surgical therapy with a goal of complete removal or debulking of papillomas and preservation of normal structures. Frequent recurrences and the need for repeated surgical interventions make this treatment a frustrating experience for both the patient and the physician. Many adjuvant therapies have been investigated but no single treatment modality proved to be effective in eradicating recurrent respiratory papillomatosis. In contrast to HIV, cytomegalovirus and hepatitis B pharmaceutical research has been less successful with human papilloma virus vaccines for a variety of reasons. This review focuses on the current status of recurrent respiratory papillomatosis and on future directions of prevention and therapy.