European journal of cancer. Part B, Oral oncology最新文献

Infections are a major cause of mortality among immunosuppressed cancer patients. The oral cavity is a possible reservoir for those microorganisms, both commensal and acquired, whose virulence is exacerbated in the immunosuppressed patient. The mouth consists of multiple habitats offering ecological niches to a variety of organisms. The object of this article is to review the literature devoted to quantitative and qualitative variations in the flora of the oral cavity during immunosuppressive treatment of cancer patients. Examination of these different studies reveals modifications of the commensal flora, as well as an increase in Gram negative rods, in staphylococci and in yeasts. These data confirm the necessity for constant surveillance of the oral cavity during chemotherapy.

Oral cavity cancer is a major health concern worldwide. Despite advances in surgery, radiotherapy and chemotherapy over the past 35 years, there has been no significant enhancement in the survival of oral cavity cancer patients. Improved survival will require identification of reliable prognostic markers that provide a rational basis for assessment of risk for progression. The altered retinoblastoma (RB) gene has been linked to the hereditary retinoblastoma. This gene is defective in several types of human malignancies. The intent of this study was to evaluate the role of the RB gene in oral cavity tumorigenesis and to explore whether or not there is a relationship between the loss of RB protein and each of several clinicopathological parameters in oral cavity carcinomas. We have analysed the expression of the RB gene in four cell Unes (J82, ML1, SaOS2 and WERI-RB-1), 182 oral cavity carcinomas (75 T1 and 107 T3 and T4 lesions) and 55 normal tissues adjacent to cancer by means of an immunohistochemical method and Western immunoblotting. The expression of RB protein was then correlated with clinical outcome in the patients with primary tumours. The significantly higher rate of altered RB expression was found in advanced oral cavity tumours (40 of 107; 37%) in comparison with low grade tumours (9 of 75; 7%). In T3 and T4 tumours, RB gene expression did not correlate with presence or absence of lymph node metastasis, degree of differentiation and patient survival. However, in the Tl cohort, poorer survival rate was seen for those patients who had a tumour with loss of RB protein. This study suggests that tumours in which the RB protein was altered were more aggressive than tumours in which the RB protein was present and that loss of RB protein in oral cavity cancer may be a prognostic variable of tumour progression.

Previous studies indicated that Taiwan betel quid is a promoter rather than an initiator during the carcinogenesis of hamster buccal pouch carcinoma. The maximum promoting activity can be demonstrated 24 weeks after betel quid implantation, following an initial application of 0.5% DMBA (7,12-dimethyl benzanthracene) three times per week for 4 weeks. In the present study, components of Taiwan betel quid and its additives (dry betel nut fibre, piper betel, slaked lime, cold aqueous extract, and hot aqueous extract) were applied respectively or in various combinations to investigate their promoting activity. One hundred and thirty Syrian hamsters were divided into 13 groups based on different combinations of the betel quid ingredients applied. The incidence of tumours in the hamster buccal pouch was significantly higher in groups exposed to dry betel nut fibre (P < 0.01) and cold aqueous extract (P < 0.05). The results indicate that betel nut fibre and cold aqueous extract are the major components of betel quid that may promote carcinogenesis in the hamster buccal pouch.

This study evaluated the distribution of cytokeratins detected by monoclonal antibodies directed against individual keratin proteins in normal human salivary glands and epithelial tumour cells of Warthin's tumour arising in parotid glands to determine a more precise mapping of their cellular distribution. The normal salivary ducts showed the presence of cytokeratins 7, 8, 18 and 19 in the intercalated, striated and excretory ducts, the primary keratins of stratified and simple epithelia with a profile very similar to the non-cornified epithelium of the oral mucosa. The basally located cells of salivary gland ducts other than myoepithelial cells were reactive for keratins 7 and 19 suggesting a close similarity in profile of keratin in the basal cells of the oral epithelium. In Warthin's tumour, keratins 7, 8, 18 and 19 were consistently detected in the epithelial cells of the tumour, a profile with a tendency to mimic the same in normal ductal epithelium. The distribution, however, was diverse and a heterogeneity was observed in the basal and luminal cells of Warthin's tumour which differed even in different areas of the same tumour specimen.

Bleomycin (BLM), a natural antibiotic toxic to dividing cells has been used for treatment of several forms of cancer. BLM has been labelled with various cations but most have turned out to be unstable in vivo. In-BLM has demonstrated high bone marrow uptake, but by using an In-111-bleomycin complex (BLMC) formed at low pH, the low in vivo stability and high bone marrow uptake can be avoided. Our premise is to combine radiotherapy and chemotherapy by using radionuclide-BLMC.

In this study we used In-111-A′2_a−c-BLMC in 28 head and neck cancer patients. Scintigraphic findings were compared to those of surgery, pre-operative radiology and proliferation markers. The injected patient activity was approximately 85 MBq, 100 MBq/mg.

The half-life of In-111 activity in serum varied from 1.5 to 3.1 h, and in urine from 1.4 to 3.7 h. More than 95% of the urine activity was excreted within 24 h. From biopsies obtained from surgical specimens of 22 patients the absolute uptakes in tumour tissues varied between 0.10 and 0.95 × 10⁻³% ID/g. Uptakes in normal tissues varied from 0.01 to 0.32 × 10⁻³% ID/g, and were always lower than in malignant tissues of the same patients. All patients were examined on the injection day with ultrasonography of the neck. Using In-111-BLMC we missed small metastatic lymph nodes (< 1 cm) in 2 patients, but there were no false positive findings. The critical organ from the dosimetric point of view was the kidney. The absorbed radiation doses with these injected activities were 19 mGy in liver, 75 mGy in kidney and 1.0 mGy in whole body (5 h mean residence time). Our results indicate that In-111-BLMC targets head and neck cancer, and identifies metastatic spread. It could possibly be applied with higher activities for adjuvant Auger-electron therapy of head and neck cancer.

The clinical and radiological features of a patient with metastatic spread of testicular teratoma to both mandibular condyles are presented. It is suggested that in patients with known systemic malignancy, a local metastatic deposit should be considered as a possible cause of unexplained pain in the temporomandibular joints.

Endogenous glucocorticoid excess with concomitant hypercortisolaemia and increased saliva level of the free active hormone, is a common feature of HIV-infected/AIDS patients. Exposure of the oral tissues to virtually uninterrupted high burden of glucocorticoids through saliva may contribute to the high frequency of oral Kaposi's sacoma (KS) in these patients. AIDS-KS cells contain unusually high levels of glucocorticoid receptor protein and recent studies indicate that growth of these cells in culture is significantly stimulated by glucocorticoids, particularly in the presence of growth factors, such as oncostatin-M. The suggestion that glucocorticoid excess may be important in the pathogenesis of KS in AIDS is not in conflict with the suspected aetiological role of newly reported KS-associated herpesviruses (KSHV), since steroid hormones may upregulate the expression of the viral gene. The latter is consistent with the observation that infection by specific oncogenic viruses does not necessarily result in cancers in the human, and does require the presence of other cellular factors or events.