Oral cancer-associated paraneoplastic syndromes

Paraneoplastic syndromes are cancer-associated endocrinological, haematological, dermatological or neurological disorders, which are directly related neither to the physical effects of the tumour mass, nor to invasion by the primary tumour, nor to metastasis of the tumour; nor are they associated either with the side-effects of anticancer treatment or with any of the complications of cancer. These syndromes are brought about by the ectopic production of biological mediators by the malignant tumour cells, or by immunological responses to the malignancy. Certain cancers are typically associated with specific paraneoplastic disorders. Though uncommonly, oral carcinomata have reportedly been associated with paraneoplastic pemphigus, humoral hypercalcaemia of malignancy, syndrome of inappropriate antidiuretic hormone, and paraneoplastic leukocytosis syndrome.

Chemotherapy- and radiotherapy-induced oral mucositis: pathobiology, epidemiology and management

Oral mucositis is a debilitating complication of anticancer treatment, characterised by erythematous, atrophic, erosive or ulcerative lesions. Oral mucositis is almost always painful, affects eating, sleeping, and speech and affects the physiological and social well-being of the patient. The pathophysiology of the condition is not well understood. Guidelines to the treatment of oral mucositis are often contradictory so that there is no evidence based standard treatment protocol. Therefore the treatment is empiric. This paper offers a brief review of current knowledge of the pathophysiology and treatment of oral mucositis.

HPV modulation of host immune responses

Host immune responses to HPV are generally low-level because the virus, being confined to basal epithelial cells is shielded from the circulating immune cells during initial stages of infection. In this location there is only a limited expression of viral proteins. Other factors contributing to the low level of host immunity are that HPV infection is non-lytic (does not cause death of the infected cell); that a functionally active immune response is generated only at later stages of HPV infection, in post-mitotic suprabasal keratinocytes where all viral genes are expressed; and that only in suprabasal keratinocytes has the HPV DNA been sufficiently amplified to be detected by the host immune-surveillance cells. In addition to the natural low-level immune responses towards HPV, HPV also employs several mechanisms to down-regulate innate and cell-mediated immunity, thus facilitating host immune evasion and persistent infection. The environment, lifestyle, the genetic make-up of the host, and the viral genomic characteristics can also influence the persistence of HPV infection, and consequential diseases. Persistent infection with high-risk HPV is associated with increased risk of developing HPV-mediated premalignancy and malignancy. It is not clear if the natural humoral immune response as opposed to vaccination is effective in eliminating primary HPV infection or in preventing progression of infection; but after initial infection, the host develops HPV-specific T cell immune responses that appear to be capable of clearing established infection, of protecting against progression of early HPV-associated intraepithelial neoplastic lesions to squamous cell carcinoma, and of preventing reinfection.

Xeroderma pigmentosum: a case report and review of the literature

Inherited molecular defects in nucleotide excision repair genes cause the autosomal recessive condition xeroderma pigmentosum. Xeroderma pigmentosum is characterized by photo-hypersensitivity of sun-exposed tissues, and by a several thousand-fold increase in the risk of developing malignant neoplasms of the skin and of the eyes. Mutations in xeroderma pigmentosum genes that regulate nucleotide excision repair, not only predispose persons with xeroderma pigmentosum to multiple malignancies, but also promote premature cutaneous and ocular ageing, and in some cases promote progressive neurodegenerative changes. This paper describes a case of xeroderma pigmentosum with advanced cutaneous squamous cell carcinoma, actinic cheilitis and ocular lesions in a 19-year-old black woman. The extensive ultraviolet radiation-induced skin and eye damage are evidence of neglect of sun-protection and lack of appropriate medical care from childhood.

Focal epithelial hyperplasia (Heck disease) related to highly active antiretroviral therapy in an HIV-seropositive child. A report of a case, and a review of the literature

Focal epithelial hyperplasia is increasingly frequently observed in rural South African communities. HIV-seropositive subjects have a higher prevalence of oral human papillomavirus (HPV) infections than immunocompetent subjects; and paradoxically, the introduction of highly active antiretroviral therapy for treatment of HIV-seropositive subjects is associated with increased frequency of focal epithelial hyperplasia. We describe a case of focal epithelial hyperplasia in an HIV-seropositive child receiving highly active antiretroviral therapy, who was successfully treated by using diode laser ablation.

The pathobiology and mechanisms of infection of HPV

There are more than 120 types of low-risk and high-risk human papillomaviruses, all of which are epitheliotropic. HPV infection may be latent, or active in a subclinical form or a symptomatic form, the latter manifesting as benign or malignant neoplasms. In basal cells with non-productive HPV infection some early HPV proteins are expressed independently of cell maturation: the productive cycle of HPV replication depends upon specific cellular factors of the maturation of the infected keratinocytes. In HPV-mediated oncogenesis, the combined pathobiological effects of E6 and E7 oncoproteins of high-risk HPV culminate in cellular genomic instability and transformation of persistently infected cells, that progress to the development of a malignant phenotype. In this article we provide insights into the stages of HPV infection, and into the viral genomic organization and replicative cycle.

Facial lymphoedema as an indicator of terminal disease in oral HIV-associated Kaposi sarcoma

Rapidly progressive facial lymphoedema developing concurrently with, or immediately after rapid enlargment of oral Kaposi sarcoma (KS) in HIV-seropositive highly active antiretroviral treatment (HAART)-naïve subjects, foretokens death. We present here an unusual case of HIV-KS in an 11-year-old HIV-seropositive HAART-naïve boy. Our patient's KS disease had had a fulminant course characterised by rapidly progressing oral HIV-KS, resorption of the mandibular alveolar bone process beneath some of the HIV-KS lesions, and rapidly progressive facial lymphoedema. He died 3 weeks after the onset of facial lymphoedema.

HIV-associated Kaposi sarcoma in African children

HIV-associated Kaposi sarcoma (HIV-KS) is common in African countries where HIV infection is pandemic and anti-retroviral medication is not readily available. Human herpesvirus-8 (HHV-8), which is the essential, but not the sole aetiological factor in KS, is endemic in sub-Saharan Africa and is substantially more prevalent in HIV-seropositive than in HIV-seronegative subjects. In children in sub-Saharan Africa, KS, whether it be HIV-KS or African endemic KS is much more prevalent than any other epidemiological forms of KS. In addition, in sub-Saharan children oral KS is common, and the life-expectancy of HIV-seropositive children with KS is short. Since generalized systemic KS is frequently associated with oral HIV-KS, it is advisable to introduce systemic cytotoxic chemotherapy early in the course of oral HIV-KS. Although the introduction of highly active antiretroviral therapy (HAART) brought about a decline in the incidence of HIV-KS worldwide, HIV-KS remains a significant problem in sub-Saharan Africa where the prevalence of HHV-8 infection is high and access to HAART is limited.

Tuberculosis part 4: Control of Mycobacterium tuberculosis transmission in dental care facilities

The risk of transmission of Mycobacterium tuberculosis (Mtb) in oral healthcare facilities is probably low, but the consequences if it occurs, are grave. The greatest risk of exposure to Mtb transmission is associated with treating dental patients from communities with a high prevalence of tuberculosis (TB) and HIV disease because these patients may have active TB but be unaware of their status. The risk of Mtb transmission in the dental surgery is heightened by dental treatment with ultrasonic and air operated high speed instruments that generate aerosols. This article offers recommendations for the necessary components of an effective Mtb infection control programme.

Tuberculosis part 3: HIV-tuberculosis co-infection

Tuberculosis is the most common opportunistic infection in HIV-seropositive persons. Tuberculosis may occur at any stage of HIV disease but the prevalence of TB increases with the progressive diminution of CD4+ T cell numbers. There is a synergistic relationship between tuberculosis and HIV infection as each accelerates the progression of the other.

Osteosarcoma of the jaw. A brief review and a case report

Osteosarcoma of the jaws accounts for 6-13% of all osteosarcomata. If not diagnosed early, it spreads extensively through the jaw and contiguous soft tissues into the nasal cavity, the maxillary sinus, the orbit and the infratemporal fossa, and may invade the oral soft tissues. A clinical finding of tooth displacement and tooth mobility associated with radiolucency/radiopacity should alert the practitioner to the possibility of osteosarcoma or some other malignancy.

Insights into immunopathogenic mechanisms of HIV infection: high levels of immune activation and HIV fitness

Progressive diminution in the number, and decline in the function of CD4+ T cells are the hallmarks of HIV infection. The pathogenic mechanisms responsible for the progression of the disease to acquired immunodeficiency syndrome (AIDS) are not well understood, but it appears that HIV-induced immune activation and increase in HIV viral fitness play an essential role in the pathogenesis of HIV infection. In this paper HIV fitness in relation to the chronic immune activation in HIV infection will be discussed.

Plasma cell gingivitis: does it exist? Report of a case and review of the literature

Plasma cell gingivitis is an uncommon inflammatory condition of uncertain aetiology. It is characterized clinically by enlarged erythemathous gingivae, a velvety texture and histopathologically by a dense plasmacytic infiltrate in the lamina propria. We present a case of a 19-year-old female who had what appeared to be plasma cell gingivitis. The clinical and histopathological differential diagnosis of plasma cell gingivitis is discussed and an argument is presented raising certain doubts whether plasma cell gingivitis is a distinct clinicopathological entity or not.

Congenital epulis. A case report

Congenital epulis (CE) is an uncommon granular cell lesion of unknown pathogenesis and uncertain histogenesis that presents at birth. It is a benign hamartoma that may interfere with feeding and respiration. The treatment of CE is by simple excision. In the 136 years since CE was first described, more than 200 cases of CE have been reported in the literature.

Idiopathic gingival fibromatosis: a review of the literature and a case report

Gingival fibromatosis is characterized by localized or generalized fibrous enlargement of the gingivae, mainly around permanent teeth. Gingival fibromatosis affects only the masticatory mucosa and does not extend beyond the muco-gingival junction. This article describes an unusual case of idiopathic gingival fibromatosis with delayed eruption of permanent teeth in an 8 year-old boy. The pathogenic mechanisms that bring about gingival fibromatosis are discussed.

Localized aggressive periodontitis associated with unusual gingival enlargement posing a diagnostic dilemma: a case report

This is a case report of localized aggressive periodontitis associated with unusual gingival enlargement. There was difficulty both clinically and histologically in deciding whether the gingival enlargement was a pyogenic granuloma or a Kaposi sarcoma. The diagnosis of Kaposi sarcoma was eventually ruled out by the failure of immunohistopathological examination to demonstrate the presence of HHV-8 DNA markers, and by the clinical response of the lesions to antimicrobial agents. Once a definitive diagnosis was made, the patient was treated conventionally.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) syndrome: suggested pathogenic mechanisms

The syndrome of enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) is an unusual syndrome and is unique to black South Africans. Major criteria for the syndrome are enamel dysplasia with generalized amelogenesis imperfecta-like features and atypical hyperplastic dental follicles with microscopic features of central odontogenic fibroma WHO-type (follicle analogue) attached to the crowns of multiple impacted teeth. Minor features of some cases are anterior open-bite malocclusion, supernumerary teeth, pulpal calcification, aberrant roots with hypercementosis, and hypodontia. The pathogenic mechanisms that lead to the development of EDHFH are unknown. We speculate that faulty synthesis of enamel matrix proteins may interfere with enamel formation and play a role in the generalized enamel hypoplasia described in this syndrome. Alterations in inductive signalling by the odontogenic epithelium mediated by enamel matrix proteins may explain the development of the follicle analogues, the root hypercementosis and the presence of dysplastic cementum deposition juxtaposed to odontogenic epithelium in the gingival overgrowth. Thus, alterations in the function of enamel matrix protein function, may be the common denominator responsible for the development of the EDHFH phenotype.

Alveolar bone necrosis and spontaneous tooth exfoliation in an HIV-seropositive subject with herpes zoster

Herpes zoster in the distribution of the maxillary and mandibular divisions of the trigeminal nerve is characterized by painful vesicular eruptions of the skin and oral mucosa in the distribution of the affected nerves. Oral complications may occur, including post-herpetic neuralgia, devitalization of teeth, abnormal development of permanent teeth, root resorption and periapical lesions. In cases where necrosis of the alveolar bony process occur it may be preceded or accompanied by spontaneous exfoliation of teeth. This usually follows the resolution of the acute phase of HZ and is more prevalent in HIV-seropositive than in HIV-seronegative subjects. A case of HZ of the trigeminal nerve in an HIV-seropositive subject, with complications of necrosis of alveolar bony process, external root resorption and tooth exfoliation is presented and the literature of HIV-associated HZ is reviewed.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia: review of the literature and report of a case

This article documents an additional case of a rare syndrome, reported only in black persons in South Africa. It is characterised by hamartomatous atypical follicular hyperplasia with central odontogenic fibroma (WHO-type)-like features attached to multiple impacted teeth, and with generalized enamel dysplasia showing features of hypoplastic amelogenesis imperfecta. Other features associated with the syndrome, but not present in all reported cases, include open-bite malocclusion, gingival overgrowth, hypodontia, pulpal calcifications and aberrant root formation of the unerupted teeth. Our present case shows the additional feature of impacted supernumerary teeth. As we cannot find any reports in the literature of the occurrence of amelogenesis imperfecta-like enamel dysplasia associated with hamartomatous follicular hyperplasia showing the features of WHO-type central odontogenic fibroma, with or without the additional features mentioned above, we propose to name this syndrome Enamel Dysplasia with Hamartomatous atypical Follicular Hyperplasia (EDHFH) syndrome.

Primary oral melanoma associated with HIV infection

POM, when it occurs, is most common in the palate and the maxillary gingiva. It has a poor prognosis. Surgical excision is the treatment of choice while radiotherapy and chemotherapy are adjunctive. This report documents an unusual case of POM and reviews field cancerization in POM.

The prognostic significance of facial lymphoedema in HIV-seropositive subjects with Kaposi sarcoma

Background

Kaposi Sarcoma (KS) is a multifocal angioproliferative neoplasm characterized by inflammation, oedema, neoangiogenesis and spindle cell proliferation. The pathogenesis of human immunodeficiency virus (HIV)-associated KS (HIV-KS) is multifactorial. HHV-8 is an essential factor but not in itself sufficient to cause HIV-KS, the development of which is influenced by HIV, by increased production of cytokines and by growth factors. Whether HIV-KS is a true malignancy or a reactive hyperplastic inflammatory condition is debatable.

Results and Conclusion

Oedema of the face, legs and hands is a prominent feature of HIV-KS and is probably caused by lymphoedema related to the HIV-KS lesions. The cases of two HIV-seropositive subjects with KS-associated facial lymphoedema are reported. Extensive oral HIV-KS in association with facial oedema in the absence of anti-retroviral treatment appears to be an indication of a poor prognosis.

Aspects of immunopathogenic mechanisms of HIV infection

Human immunodeficiency virus (HIV) infection is characterized by progressive deterioration of the immune system nearly always resulting in death. Depletion in the numbers of CD4+ T cells is the hallmark of HIV infection and is central to the development of the clinical signs and symptoms that are characteristic of HIV disease. Other factors influencing the progression of HIV disease include the HIV viral load, the nature of the particular infecting HIV, and the level of competence of the immune effector cells.

Oral histoplasmosis as the initial indication of HIV infection: a case report

Histoplasmosis is an opportunistic infection. In HIV-seropositive subjects, histoplasmosis tends to have a progressive and disseminated course. Oral lesions occur frequently and multiple sites within the mouth can be affected. Diagnosis of histoplasmosis is made by microscopic identification and culture of the fungus in material taken from the affected site. We present a case of oral histoplasmosis in which the mouth was the primary site of the fungal disease and this was the initial indicator of HIV infection. There were lesions of the gingivae and there was destruction of the hard palate with extension into the right maxillary sinus and the right nasal cavity.